Trial Outcomes & Findings for Dose Escalation and Expansion Study of GSK525762 in Combination With Fulvestrant in Participants With Hormone Receptor-positive (HR+)/Human Epidermal Growth Factor Receptor 2 Negative (HER2-) Advanced or Metastatic Breast Cancer (NCT NCT02964507)

Last Updated: 2024-08-29

Results Overview

An AE is defined as any untoward medical occurrence in a participant or clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. A SAE is defined as any untoward medical occurrence that, at any dose results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect, any other situation such as important medical events according to medical or scientific judgement or is associated with liver injury and impaired liver function. Any other adverse event apart from SAE is considered as non-SAE.

Recruitment status

TERMINATED

Study phase

PHASE1

Target enrollment

124 participants

Primary outcome timeframe

Up to 3 year and 8 months

Results posted on

2024-08-29

Participant Flow

This was a Phase I/II study of GSK525762 in combination with fulvestrant in participants with hormone receptor-positive/HER2-negative (HR+/HER2-)advanced/metastatic breast cancer. Out of 124 participants enrolled in the study, 1 participant was not treated.

As per study protocol, an interim analysis was conducted during phase 1,following assessment of data,phase 2 was not initiated. However,all existing participants receiving treatment in phase 1 who were considered to be deriving benefit were continued on the study (at investigators decision),until progression or death/withdrawal.As per the protocol the study was considered as completed when the last participant completed/discontinued study treatment and completed the end of treatment visit

Participant milestones

Participant milestones
Measure	Phase I-GSK525762 60 mg+FUL 500 mg (AI Failure) Participants with aromatose inhibitor (AI) failure received GSK525762 60 milligrams (mg) tablet orally once daily and Fulvestrant (FUL) 500 mg was administered intramuscularly (IM) on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+AI Failure <12M) Participants with Cyclin-Dependent Kinase (CDK4/6)/AI failure within 12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Overall Study STARTED	33	12	42	7	18	11
Overall Study COMPLETED	7	1	17	1	2	3
Overall Study NOT COMPLETED	26	11	25	6	16	8

Reasons for withdrawal

Reasons for withdrawal
Measure	Phase I-GSK525762 60 mg+FUL 500 mg (AI Failure) Participants with aromatose inhibitor (AI) failure received GSK525762 60 milligrams (mg) tablet orally once daily and Fulvestrant (FUL) 500 mg was administered intramuscularly (IM) on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+AI Failure <12M) Participants with Cyclin-Dependent Kinase (CDK4/6)/AI failure within 12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Overall Study Protocol specified Withdrawal criteria met	0	1	0	0	1	0
Overall Study Study terminated by Sponsor	9	1	9	3	3	2
Overall Study Other	3	0	0	0	1	0
Overall Study Death	11	9	12	2	10	5
Overall Study Withdrawal by Subject	1	0	1	1	0	1
Overall Study Physician Decision	2	0	3	0	1	0

Baseline Characteristics

Dose Escalation and Expansion Study of GSK525762 in Combination With Fulvestrant in Participants With Hormone Receptor-positive (HR+)/Human Epidermal Growth Factor Receptor 2 Negative (HER2-) Advanced or Metastatic Breast Cancer

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Phase I-GSK525762 60 mg+FUL 500 mg (AI Failure) n=33 Participants Participants with aromatose inhibitor (AI) failure received GSK525762 60 milligrams (mg) tablet orally once daily and Fulvestrant (FUL) 500 mg was administered intramuscularly (IM) on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+AI Failure <12M) n=12 Participants Participants with Cyclin-Dependent Kinase (CDK4/6)/AI failure within 12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase II-GSK525762+FUL Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Total n=123 Participants Total of all reporting groups
Age, Continuous	60.6 Years STANDARD_DEVIATION 9.40 • n=5 Participants	53.3 Years STANDARD_DEVIATION 8.48 • n=7 Participants	55.7 Years STANDARD_DEVIATION 9.82 • n=5 Participants	58.7 Years STANDARD_DEVIATION 7.97 • n=4 Participants	54.4 Years STANDARD_DEVIATION 8.45 • n=21 Participants	51.5 Years STANDARD_DEVIATION 12.04 • n=8 Participants	—	—	56.4 Years STANDARD_DEVIATION 9.80 • n=42 Participants
Sex: Female, Male Female	33 Participants n=5 Participants	12 Participants n=7 Participants	42 Participants n=5 Participants	7 Participants n=4 Participants	18 Participants n=21 Participants	11 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	123 Participants n=42 Participants
Sex: Female, Male Male	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	0 Participants n=42 Participants
Race/Ethnicity, Customized Central south Asian Heritage	0 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	1 Participants n=42 Participants
Race/Ethnicity, Customized East Asian Heritage	7 Participants n=5 Participants	2 Participants n=7 Participants	8 Participants n=5 Participants	1 Participants n=4 Participants	6 Participants n=21 Participants	2 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	26 Participants n=42 Participants
Race/Ethnicity, Customized Japanese Heritage	1 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	1 Participants n=42 Participants
Race/Ethnicity, Customized South East Asian Heritage	1 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	1 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	2 Participants n=42 Participants
Race/Ethnicity, Customized Black or African American	2 Participants n=5 Participants	1 Participants n=7 Participants	2 Participants n=5 Participants	1 Participants n=4 Participants	1 Participants n=21 Participants	1 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	8 Participants n=42 Participants
Race/Ethnicity, Customized Arabic/North African Heritage	1 Participants n=5 Participants	0 Participants n=7 Participants	2 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	3 Participants n=42 Participants
Race/Ethnicity, Customized White/Caucasian/European Heritage	19 Participants n=5 Participants	8 Participants n=7 Participants	28 Participants n=5 Participants	5 Participants n=4 Participants	11 Participants n=21 Participants	7 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	78 Participants n=42 Participants
Race/Ethnicity, Customized Multiple	1 Participants n=5 Participants	1 Participants n=7 Participants	0 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	2 Participants n=42 Participants
Race/Ethnicity, Customized Missing	1 Participants n=5 Participants	0 Participants n=7 Participants	1 Participants n=5 Participants	0 Participants n=4 Participants	0 Participants n=21 Participants	0 Participants n=8 Participants	0 Participants n=8 Participants	0 Participants n=24 Participants	2 Participants n=42 Participants

PRIMARY outcome

Timeframe: Up to 3 year and 8 months

Population: All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant).

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Number of Participants With Non-serious Adverse Events (AEs) and Serious Adverse Events (SAEs) Non-serious AEs	33 Participants	12 Participants	42 Participants	7 Participants	18 Participants	11 Participants
Phase I: Number of Participants With Non-serious Adverse Events (AEs) and Serious Adverse Events (SAEs) SAEs	5 Participants	1 Participants	10 Participants	3 Participants	6 Participants	2 Participants

PRIMARY outcome

Timeframe: Up to 28 days

Population: All Treated Population.

An event was considered DLT if it occurred within first 28 days of treatment and met one of following DLT criteria: Grade3 or greater neutropenia for \>=5 days, febrile neutropenia, Grade4 anemia of any duration, Grade4 thrombocytopenia of any duration or Grade3 thrombocytopenia with bleeding, alanine aminotransferase (ALT) \>3 times (x) upper limit of normal (ULN)+bilirubin \>=2x ULN (\>35 % direct) or ALT between 3-5xULN with bilirubin \<2xULN but with hepatitis symptoms or rash, Grade3 nausea,vomiting or diarrhea that did not improve within 72hour despite appropriate supportive treatment(s), Grade4 nausea,vomiting,or diarrhea, Grade3 hypertension (uncontrolled despite addition of upto 2 antihypertensive medications), Grade4 hypertension, other Grade3 or greater clinically significant non-hematologic toxicity (including QT duration corrected for heart rate by Fridericia's formula (QTcF), ejection fraction \<lower limit of normal (LLN) with an absolute decrease of \>10% from Baseline.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Number of Participants With Dose Limiting Toxicities (DLTs)	2 Participants	0 Participants	1 Participants	1 Participants	0 Participants	2 Participants

PRIMARY outcome

Timeframe: Up to 3 year and 8 months

Population: All Treated Population.

Number of participants with dose reductions and dose interruption or delay due to any reason is presented.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Number of Participants With Dose Reductions and Dose Interruption/Delays Dose reduction	9 Participants	3 Participants	14 Participants	3 Participants	7 Participants	8 Participants
Phase I: Number of Participants With Dose Reductions and Dose Interruption/Delays Dose interruption/delay	23 Participants	9 Participants	23 Participants	4 Participants	15 Participants	9 Participants

PRIMARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population consisted of all participants who received at least one dose of GSK525762 and fulvestrant.

Objective Response Rate is defined as the percentage of participants who demonstrate a Best Response of confirmed complete response (CR) or partial response (PR), as assessed by the investigator per response evaluation criteria in solid tumors (RECIST) version (v) 1.1 criteria.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Objective Response Rate-Investigator Assessment	21 Percentage of participants Interval 9.0 to 38.9	0 Percentage of participants Interval 0.0 to 26.5	12 Percentage of participants Interval 4.0 to 25.6	0 Percentage of participants Interval 0.0 to 41.0	17 Percentage of participants Interval 3.6 to 41.4	9 Percentage of participants Interval 0.2 to 41.3

PRIMARY outcome

Timeframe: Day 1: Pre-dose, 0.5, 1, 3 hours on Weeks 1 and 3; Day 1: Pre-dose, 0.5-1, 4-8 hours on Week 5; Day 1: Pre-dose, 0.5-1 hour on Weeks 9, 17, 25

Population: PK Population comprised of participants from the All Treated Population for whom a PK sample was obtained and analyzed. Only those participants with data available at the indicated time points were analyzed (indicated by n=X in category titles).

Blood samples were collected at indicated time points for pharmacokinetic (PK) analysis of GSK525762.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=31 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=41 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Plasma Concentration of GSK525762 Week 1 Day 1, Pre-dose, n=30,11,41,7,17,11	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose
Phase I: Plasma Concentration of GSK525762 Week 1 Day 1, 0.5 hour, n=31,11,40,7,17,10	895.466 Nanograms per milliliter Standard Deviation 520.7900	814.364 Nanograms per milliliter Standard Deviation 465.7197	824.081 Nanograms per milliliter Standard Deviation 605.1745	646.251 Nanograms per milliliter Standard Deviation 537.3585	969.265 Nanograms per milliliter Standard Deviation 659.5862	1155.300 Nanograms per milliliter Standard Deviation 329.8983
Phase I: Plasma Concentration of GSK525762 Week 1 Day 1, 1 hour, n=31,10,40,7,18,10	855.734 Nanograms per milliliter Standard Deviation 374.3789	828.800 Nanograms per milliliter Standard Deviation 216.0544	947.343 Nanograms per milliliter Standard Deviation 443.7234	634.300 Nanograms per milliliter Standard Deviation 331.3116	1061.722 Nanograms per milliliter Standard Deviation 397.9207	1069.400 Nanograms per milliliter Standard Deviation 269.4864
Phase I: Plasma Concentration of GSK525762 Week 1 Day 1, 3 hours, n=31,10,39,6,17,10	637.097 Nanograms per milliliter Standard Deviation 220.5013	526.400 Nanograms per milliliter Standard Deviation 106.3591	717.769 Nanograms per milliliter Standard Deviation 293.5412	732.833 Nanograms per milliliter Standard Deviation 394.3660	831.176 Nanograms per milliliter Standard Deviation 293.0363	782.600 Nanograms per milliliter Standard Deviation 191.9283
Phase I: Plasma Concentration of GSK525762 Week 3 Day 1, Pre-dose, n=29,12,31,5,16,8	7.046 Nanograms per milliliter Standard Deviation 8.2049	15.797 Nanograms per milliliter Standard Deviation 20.7736	8.598 Nanograms per milliliter Standard Deviation 13.2639	150.410 Nanograms per milliliter Standard Deviation 295.0514	11.371 Nanograms per milliliter Standard Deviation 17.8450	6.799 Nanograms per milliliter Standard Deviation 5.7108
Phase I: Plasma Concentration of GSK525762 Week 3 Day 1, 0.5 hour, n=28,11,29,4,13,7	766.179 Nanograms per milliliter Standard Deviation 330.0370	680.936 Nanograms per milliliter Standard Deviation 435.2668	504.516 Nanograms per milliliter Standard Deviation 342.6658	730.250 Nanograms per milliliter Standard Deviation 410.6356	808.846 Nanograms per milliliter Standard Deviation 548.7639	917.714 Nanograms per milliliter Standard Deviation 498.7183
Phase I: Plasma Concentration of GSK525762 Week 3 Day 1, 1 hour, n=28,11,30,5,13,7	737.536 Nanograms per milliliter Standard Deviation 310.4540	576.427 Nanograms per milliliter Standard Deviation 298.5082	581.073 Nanograms per milliliter Standard Deviation 273.6803	596.800 Nanograms per milliliter Standard Deviation 134.6540	875.077 Nanograms per milliliter Standard Deviation 343.5570	895.286 Nanograms per milliliter Standard Deviation 358.3172
Phase I: Plasma Concentration of GSK525762 Week 3 Day 1, 3 hours, n=28,10,29,5,13,7	423.500 Nanograms per milliliter Standard Deviation 190.6163	447.700 Nanograms per milliliter Standard Deviation 179.1889	369.179 Nanograms per milliliter Standard Deviation 171.4981	422.800 Nanograms per milliliter Standard Deviation 120.6512	471.154 Nanograms per milliliter Standard Deviation 160.2908	523.714 Nanograms per milliliter Standard Deviation 207.9308
Phase I: Plasma Concentration of GSK525762 Week 5 Day 1, Pre-dose, n=26,9,34,5,14,10	5.804 Nanograms per milliliter Standard Deviation 7.7777	15.251 Nanograms per milliliter Standard Deviation 18.1145	66.527 Nanograms per milliliter Standard Deviation 198.8847	15.814 Nanograms per milliliter Standard Deviation 21.5282	14.603 Nanograms per milliliter Standard Deviation 17.0653	77.465 Nanograms per milliliter Standard Deviation 217.4469
Phase I: Plasma Concentration of GSK525762 Week 5 Day 1, 0.5-1 hour, n=24,7,26,3,11,7	640.700 Nanograms per milliliter Standard Deviation 380.5152	463.854 Nanograms per milliliter Standard Deviation 476.0195	555.237 Nanograms per milliliter Standard Deviation 336.1938	705.667 Nanograms per milliliter Standard Deviation 208.2218	685.773 Nanograms per milliliter Standard Deviation 446.6621	457.229 Nanograms per milliliter Standard Deviation 301.9096
Phase I: Plasma Concentration of GSK525762 Week 5 Day 1, 4-8 hours, n=6,1,9,1,5,0	306.900 Nanograms per milliliter Standard Deviation 153.8008	145.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	303.000 Nanograms per milliliter Standard Deviation 177.1489	431.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	352.400 Nanograms per milliliter Standard Deviation 98.5890	—
Phase I: Plasma Concentration of GSK525762 Week 9 Day 1, Pre-dose, n=17,2,23,2,10,4	7.257 Nanograms per milliliter Standard Deviation 11.2876	5.055 Nanograms per milliliter Standard Deviation 0.7142	9.000 Nanograms per milliliter Standard Deviation 13.3106	3.265 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to high proportion of non-quantifiable (NQ) values (more than \[\>\] 30 percent \[%\] of values were imputed).	16.469 Nanograms per milliliter Standard Deviation 23.7102	6.640 Nanograms per milliliter Standard Deviation 7.0298
Phase I: Plasma Concentration of GSK525762 Week 9 Day 1, 0.5-1 hour, n=13,1,17,2,6,3	607.408 Nanograms per milliliter Standard Deviation 528.6891	69.400 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	445.291 Nanograms per milliliter Standard Deviation 388.9562	817.000 Nanograms per milliliter Standard Deviation 287.0854	621.867 Nanograms per milliliter Standard Deviation 440.4829	309.627 Nanograms per milliliter Standard Deviation 375.4223
Phase I: Plasma Concentration of GSK525762 Week 17 Day 1, Pre-dose, n=11,2,8,2,6,3	9.401 Nanograms per milliliter Standard Deviation 13.0880	1.365 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to high proportion of non-quantifiable (NQ) values (more than \[\>\] 30 percent \[%\] of values were imputed).	3.591 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to high proportion of non-quantifiable (NQ) values (more than \[\>\] 30 percent \[%\] of values were imputed).	16.850 Nanograms per milliliter Standard Deviation 2.0506	7.217 Nanograms per milliliter Standard Deviation 10.1456	7.270 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to high proportion of non-quantifiable (NQ) values (more than \[\>\] 30 percent \[%\] of values were imputed).
Phase I: Plasma Concentration of GSK525762 Week 17 Day 1, 0.5-1 hour, n=9,2,9,2,4,1	372.778 Nanograms per milliliter Standard Deviation 214.7812	32.100 Nanograms per milliliter Standard Deviation 30.2642	521.241 Nanograms per milliliter Standard Deviation 404.3103	270.000 Nanograms per milliliter Standard Deviation 354.9676	640.000 Nanograms per milliliter Standard Deviation 273.7846	214.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant
Phase I: Plasma Concentration of GSK525762 Week 25 Day 1, Pre-dose, n=9,1,5,2,4,1	34.847 Nanograms per milliliter Standard Deviation 92.3723	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	10.198 Nanograms per milliliter Standard Deviation 10.4909	10.740 Nanograms per milliliter Standard Deviation 9.1358	1.560 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to high proportion of non-quantifiable (NQ) values (more than \[\>\] 30 percent \[%\] of values were imputed).	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose
Phase I: Plasma Concentration of GSK525762 Week 25 Day 1, 0.5-1 hour, n=5,0,6,2,2,1	418.000 Nanograms per milliliter Standard Deviation 173.5439	—	380.483 Nanograms per milliliter Standard Deviation 338.1430	251.350 Nanograms per milliliter Standard Deviation 225.7792	314.000 Nanograms per milliliter Standard Deviation 90.5097	186.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant

PRIMARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population. Phase II of study was not initiated hence data was not collected and analyzed.

PFS is defined as the time (in months) from the date of first dose until the date of first documented progressive disease (PD), as assessed by the investigator per RECIST v1.1 criteria, or date of death due to any cause, whichever occurs first. PD is defined as at least a 20% increase in the sum of the diameters of target lesions taking as a reference the smallest sum of diameters for this study.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to 4 year and 4 months

Population: All Treated Population.

Number of participants who withdrew due to toxicity and changes in safety assessment including laboratory parameters and vital signs have been presented.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Number of Participants Who Withdrew Due to Toxicity and Changes in Safety Assessment	6 Participants	0 Participants	6 Participants	2 Participants	1 Participants	2 Participants

SECONDARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population.

DCR is defined as the percentage of participants in the population with a confirmed complete response (CR), confirmed partial response (PR), or stable disease (SD) lasting \>=6 months, as assessed by the investigator per RECIST v1.1 criteria.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Disease Control Rate (DCR)	36 Percentage of participants Interval 20.4 to 54.9	0 Percentage of participants Interval 0.0 to 26.5	17 Percentage of participants Interval 7.0 to 31.4	14 Percentage of participants Interval 0.4 to 57.9	28 Percentage of participants Interval 9.7 to 53.5	9 Percentage of participants Interval 0.2 to 41.3

SECONDARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population. Only those participants with a BOR of confirmed CR or PR based on RECIST v1.1 were analyzed hence N=0 for Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+AI Failure \<12M) and Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure\>=12M Bone Only Disease arms.

DoR is defined as the time (in months) from date of first documented evidence of confirmed CR or PR to the date of first documented PD, as assessed by the investigator per RECIST v1.1 criteria, or to the date of death due to any cause among participants with a Best overall response (BOR) of confirmed CR or PR.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=7 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=5 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=3 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=1 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Duration of Response (DoR)	13.1 Months Interval 6.5 to 26.3	—	5.8 Months Interval 5.7 to \<75% of participants experienced the event within the treatment arm. Hence, third-quartile could not be derived.	—	14.0 Months Interval 5.4 to 16.4	4.3 Months Inter-quartile range is not applicable due to single participant, and the median value presented here is the actual DOR for this single participant

SECONDARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population.

PFS is defined as the time (in months) from the date of first dose until the date of first documented PD, as assessed by the investigator per RECIST v1.1 criteria, or date of death due to any cause, whichever occurs first. PD is defined as at least a 20% increase in the sum of the diameters of target lesions taking as a reference the smallest sum of diameters for this study.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Progression-free Survival (PFS)	5.6 Months Interval 3.5 to 14.1	1.7 Months Interval 1.6 to 2.1	2.1 Months Interval 1.7 to 7.1	7.2 Months Interval 3.7 to \<75% of participants experienced the event within the treatment arm. Hence, third-quartile could not be derived.	4.0 Months Interval 1.8 to 9.4	1.8 Months Interval 1.7 to 3.6

SECONDARY outcome

Timeframe: Day 1: Pre-dose, 0.5, 1, 3 hours on Weeks 1 and 3; Day 1: Pre-dose, 0.5-1, 4-8 hours on Week 5, Day 1: pre-dose, 0.5-1 hour on Weeks 9, 17, 25

Population: PK Population. Only those participants with data available at the indicated time points were analyzed (indicated by n=X in category titles).

Blood samples were collected at indicated time points for PK analysis of GSK3529246. GSK3529246 is an active metabolite of GSK525762.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=31 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=41 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Plasma Concentration of GSK3529246 Week 1 Day 1, Pre-dose, n=30,11,41,7,17,11	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose
Phase I: Plasma Concentration of GSK3529246 Week 1 Day 1, 0.5 hour, n=31,11,39, 7,17,10	174.474 Nanograms per milliliter Standard Deviation 143.3693	126.818 Nanograms per milliliter Standard Deviation 84.5894	135.012 Nanograms per milliliter Standard Deviation 128.9738	115.419 Nanograms per milliliter Standard Deviation 108.8723	202.224 Nanograms per milliliter Standard Deviation 225.2895	186.970 Nanograms per milliliter Standard Deviation 108.3133
Phase I: Plasma Concentration of GSK3529246 Week 1 Day 1, 1 hour, n=31,11,41,7,18,10	249.793 Nanograms per milliliter Standard Deviation 128.5670	205.364 Nanograms per milliliter Standard Deviation 70.6856	228.597 Nanograms per milliliter Standard Deviation 118.1550	175.197 Nanograms per milliliter Standard Deviation 154.0632	327.072 Nanograms per milliliter Standard Deviation 186.8822	299.100 Nanograms per milliliter Standard Deviation 92.9043
Phase I: Plasma Concentration of GSK3529246 Week 1 Day 1, 3 hours, n=31,11,39,6,17,10	276.516 Nanograms per milliliter Standard Deviation 67.1798	216.364 Nanograms per milliliter Standard Deviation 50.0685	262.044 Nanograms per milliliter Standard Deviation 91.2467	243.517 Nanograms per milliliter Standard Deviation 136.5840	365.059 Nanograms per milliliter Standard Deviation 130.8231	300.000 Nanograms per milliliter Standard Deviation 95.1595
Phase I: Plasma Concentration of GSK3529246 Week 3 Day 1, Pre-dose, n=29,12,31,5,16,8	37.972 Nanograms per milliliter Standard Deviation 31.9814	58.708 Nanograms per milliliter Standard Deviation 64.1009	42.213 Nanograms per milliliter Standard Deviation 30.7403	121.820 Nanograms per milliliter Standard Deviation 190.5127	48.013 Nanograms per milliliter Standard Deviation 39.6626	49.230 Nanograms per milliliter Standard Deviation 40.3798
Phase I: Plasma Concentration of GSK3529246 Week 3 Day 1, 0.5 hour, n=28,11,30,4,13,7	290.482 Nanograms per milliliter Standard Deviation 155.8106	243.736 Nanograms per milliliter Standard Deviation 130.5650	195.037 Nanograms per milliliter Standard Deviation 147.9176	192.275 Nanograms per milliliter Standard Deviation 149.9568	256.669 Nanograms per milliliter Standard Deviation 173.4439	288.671 Nanograms per milliliter Standard Deviation 166.5404
Phase I: Plasma Concentration of GSK3529246 Week 3 Day 1, 1 hour, n=28,11,30,5,13,7	414.143 Nanograms per milliliter Standard Deviation 118.8203	294.573 Nanograms per milliliter Standard Deviation 102.1516	323.767 Nanograms per milliliter Standard Deviation 169.5878	271.200 Nanograms per milliliter Standard Deviation 145.3227	511.692 Nanograms per milliliter Standard Deviation 196.3468	441.571 Nanograms per milliliter Standard Deviation 140.2353
Phase I: Plasma Concentration of GSK3529246 Week 3 Day 1, 3 hours, n=28,10,29,5,13,7	369.821 Nanograms per milliliter Standard Deviation 85.0124	341.500 Nanograms per milliliter Standard Deviation 95.5118	321.404 Nanograms per milliliter Standard Deviation 131.8554	252.000 Nanograms per milliliter Standard Deviation 96.1587	438.692 Nanograms per milliliter Standard Deviation 91.5946	403.571 Nanograms per milliliter Standard Deviation 96.7348
Phase I: Plasma Concentration of GSK3529246 Week 5 Day 1, Pre-dose, n=26,9,34,5,14,10	37.480 Nanograms per milliliter Standard Deviation 32.2441	41.600 Nanograms per milliliter Standard Deviation 24.1873	56.659 Nanograms per milliliter Standard Deviation 70.2933	36.620 Nanograms per milliliter Standard Deviation 26.8511	52.243 Nanograms per milliliter Standard Deviation 44.0710	54.231 Nanograms per milliliter Standard Deviation 57.2752
Phase I: Plasma Concentration of GSK3529246 Week 5 Day 1, 0.5-1 hour, n=24,7,26,3,11,7	270.979 Nanograms per milliliter Standard Deviation 153.7445	237.614 Nanograms per milliliter Standard Deviation 211.1272	211.846 Nanograms per milliliter Standard Deviation 171.4081	170.800 Nanograms per milliliter Standard Deviation 66.2851	295.518 Nanograms per milliliter Standard Deviation 235.4897	203.486 Nanograms per milliliter Standard Deviation 111.2642
Phase I: Plasma Concentration of GSK3529246 Week 5 Day 1, 4-8 hours, n=6,1,9,1,5,0	263.833 Nanograms per milliliter Standard Deviation 52.9619	208.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	322.778 Nanograms per milliliter Standard Deviation 166.2354	292.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	382.400 Nanograms per milliliter Standard Deviation 98.2588	—
Phase I: Plasma Concentration of GSK3529246 Week 9 Day 1, Pre-dose, n=17,2,23,2,10,4	31.041 Nanograms per milliliter Standard Deviation 28.3504	33.850 Nanograms per milliliter Standard Deviation 19.4454	39.323 Nanograms per milliliter Standard Deviation 40.8779	22.700 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to high proportion of non-quantifiable (NQ) values (more than \[\>\] 30 percent \[%\] of values were imputed).	58.890 Nanograms per milliliter Standard Deviation 62.2330	69.625 Nanograms per milliliter Standard Deviation 53.3875
Phase I: Plasma Concentration of GSK3529246 Week 9 Day 1, 0.5-1 hour, n=13,1,17,2,6,3	244.162 Nanograms per milliliter Standard Deviation 189.0153	36.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	178.914 Nanograms per milliliter Standard Deviation 148.8777	228.000 Nanograms per milliliter Standard Deviation 140.0071	283.667 Nanograms per milliliter Standard Deviation 177.1211	161.367 Nanograms per milliliter Standard Deviation 113.1437
Phase I: Plasma Concentration of GSK3529246 Week 17 Day 1, Pre-dose, n=11,2,8,2,6,3	41.445 Nanograms per milliliter Standard Deviation 35.8541	21.450 Nanograms per milliliter Standard Deviation 5.4447	21.214 Nanograms per milliliter Standard Deviation 27.8382	72.450 Nanograms per milliliter Standard Deviation 55.9321	44.483 Nanograms per milliliter Standard Deviation 48.7589	84.600 Nanograms per milliliter Standard Deviation 74.6129
Phase I: Plasma Concentration of GSK3529246 Week 17 Day 1, 0.5-1 hour, n=9,2,9,2,4,1	189.422 Nanograms per milliliter Standard Deviation 146.0021	71.800 Nanograms per milliliter Standard Deviation 66.7509	183.671 Nanograms per milliliter Standard Deviation 149.1568	129.050 Nanograms per milliliter Standard Deviation 135.6938	322.500 Nanograms per milliliter Standard Deviation 237.0787	301.000 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant
Phase I: Plasma Concentration of GSK3529246 Week 25 Day 1, Pre-dose, n=9,1,5,2,4,1	65.756 Nanograms per milliliter Standard Deviation 125.0011	30.100 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	49.700 Nanograms per milliliter Standard Deviation 26.2679	64.500 Nanograms per milliliter Standard Deviation 60.1041	20.508 Nanograms per milliliter Standard Deviation 29.5669	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose
Phase I: Plasma Concentration of GSK3529246 Week 25 Day 1, 0.5-1 hour, n=5,0,6,2,2,1	203.160 Nanograms per milliliter Standard Deviation 192.2849	—	220.367 Nanograms per milliliter Standard Deviation 195.6110	204.950 Nanograms per milliliter Standard Deviation 164.1195	121.300 Nanograms per milliliter Standard Deviation 90.0854	76.300 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant

SECONDARY outcome

Timeframe: Day 1: Pre-dose on Weeks 1, 3, 5, 9, 17, 25

Population: PK Population. Only those participants with data available at the indicated time points were analyzed (indicated by n=X in category titles).

Blood samples were collected at indicated time points for PK analysis of Fulvestrant.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=30 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=11 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=40 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=17 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Plasma Concentration of Fulvestrant Week 25 Day 1, Pre-dose, n=10,1,4,1,4,1	18.07473 Nanograms per milliliter Standard Deviation 5.933472	14.21220 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	18.60548 Nanograms per milliliter Standard Deviation 5.300211	19.05100 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	16.05110 Nanograms per milliliter Standard Deviation 2.384935	12.24970 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant
Phase I: Plasma Concentration of Fulvestrant Week 1 Day 1, Pre-dose, n=30,11,40,6,17,11	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose	NA Nanograms per milliliter Standard Deviation NA No concentration values were detected for pre-dose
Phase I: Plasma Concentration of Fulvestrant Week 3 Day 1, Pre-dose, n=30,11,32,7,16,10	13.32481 Nanograms per milliliter Standard Deviation 6.603131	9.42742 Nanograms per milliliter Standard Deviation 3.584881	12.44415 Nanograms per milliliter Standard Deviation 5.669148	11.34839 Nanograms per milliliter Standard Deviation 2.085675	12.41568 Nanograms per milliliter Standard Deviation 4.873113	10.25047 Nanograms per milliliter Standard Deviation 3.121508
Phase I: Plasma Concentration of Fulvestrant Week 5 Day 1, Pre-dose, n=25,9,31,5,16,10	19.82642 Nanograms per milliliter Standard Deviation 6.917439	14.72467 Nanograms per milliliter Standard Deviation 3.338039	16.51574 Nanograms per milliliter Standard Deviation 5.957079	15.35394 Nanograms per milliliter Standard Deviation 5.395372	16.87293 Nanograms per milliliter Standard Deviation 8.018589	13.83940 Nanograms per milliliter Standard Deviation 4.449118
Phase I: Plasma Concentration of Fulvestrant Week 9 Day 1, Pre-dose, n=19,3,19,1,10,5	16.33764 Nanograms per milliliter Standard Deviation 5.719390	13.05750 Nanograms per milliliter Standard Deviation 4.266495	13.98242 Nanograms per milliliter Standard Deviation 4.138764	20.43840 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	11.10370 Nanograms per milliliter Standard Deviation 2.864192	11.84244 Nanograms per milliliter Standard Deviation 4.615995
Phase I: Plasma Concentration of Fulvestrant Week 17 Day 1, Pre-dose, n=15,2,6,1,6,3	16.70103 Nanograms per milliliter Standard Deviation 5.826390	20.63475 Nanograms per milliliter Standard Deviation 7.753497	13.62853 Nanograms per milliliter Standard Deviation 1.536930	12.59940 Nanograms per milliliter Standard Deviation NA Standard deviation could not be calculated due to single participant	12.81337 Nanograms per milliliter Standard Deviation 3.550671	16.33830 Nanograms per milliliter Standard Deviation 4.410823

SECONDARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population. Phase II of study was not initiated hence data was not collected and analyzed.

OS is defined as the interval of time (in months) between the date of first dose and the date of death due to any cause.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population. Phase II of study was not initiated hence data was not collected and analyzed.

ORR is defined as the percentage of participants in the population who demonstrate a BOR of confirmed CR or PR, as assessed by the investigator per RECIST v1.1 criteria.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to 3 year and 8 months

Population: Modified All Treated Population. Phase II of study was not initiated hence data was not collected and analyzed.

DCR is defined as the percentage of participants in the population with a confirmed CR, confirmed PR, or SD lasting \>=6 months, as assessed by the investigator per RECIST v1.1 criteria.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Day 1: Pre-dose, 0.5, 1, 3 hours on Weeks 1 and 3; Day 1: Pre-dose, 0.5-1, 4-8 hours on Week 5, Day 1: Pre-dose, 0.5-1 hour on Weeks 9, 17, 25

Population: PK Population. Phase II of study was not initiated hence data was not collected and analyzed.

Blood samples were planned to be collected for PK analysis of GSK525762 and GSK3529246. GSK3529246 is metabolite of GSK525762.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Day 1: Pre-dose on Weeks 1, 3, 5, 9, 17, 25

Population: PK Population. Phase II of study was not initiated hence data was not collected and analyzed.

Blood samples were planned to be collected for PK analysis of fulvestrant.

Outcome measures

Outcome data not reported

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to 4 year and 4 months

Population: All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant).

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Number of Participants With Non-serious Adverse Events (AEs) and Serious Adverse Events (SAEs) Until End of the Study Non-serious AEs	33 Participants	12 Participants	42 Participants	7 Participants	18 Participants	11 Participants
Phase I: Number of Participants With Non-serious Adverse Events (AEs) and Serious Adverse Events (SAEs) Until End of the Study SAEs	5 Participants	1 Participants	10 Participants	3 Participants	6 Participants	2 Participants

OTHER_PRE_SPECIFIED outcome

Timeframe: Up to 4 year and 4 months

Population: All Treated Population.

Number of participants with dose reductions and dose interruption or delay due to any reason is presented. Number of participants with dose reductions and dose interruption or delay due to any reason from start of the treatment until end of the study were reported.

Outcome measures

Outcome measures
Measure	Phase II-GSK525762+FUL n=33 Participants Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL n=12 Participants Participants were planned to receive Placebo+FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase I-GSK525762 60 mg+FUL 500 mg (CDK4/6+ AI Failure >= 12M) n=42 Participants Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60+FUL500mg CDK4/6+AI Failure>=12M Bone Only Disease n=7 Participants Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg + FUL 500 mg (AI Failure) n=18 Participants Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80 mg + FUL 500 mg (CDK4/6+AI Failure) n=11 Participants Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.
Phase I: Number of Participants With Dose Reductions and Dose Interruption/Delays Until End of the Study Dose reduction	9 Participants	3 Participants	14 Participants	3 Participants	7 Participants	8 Participants
Phase I: Number of Participants With Dose Reductions and Dose Interruption/Delays Until End of the Study Dose interruption/delay	23 Participants	9 Participants	23 Participants	4 Participants	15 Participants	9 Participants

Adverse Events

Phase I- GSK525762 60mg+FUL 500mg (AI Failure)

Serious events: 5 serious events

Other events: 33 other events

Deaths: 11 deaths

Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure < 12M)

Serious events: 1 serious events

Other events: 12 other events

Deaths: 9 deaths

Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure >=12M)

Serious events: 10 serious events

Other events: 42 other events

Deaths: 12 deaths

Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure >=12M Bone Only Disease

Serious events: 3 serious events

Other events: 7 other events

Deaths: 2 deaths

Phase I-GSK525762 80mg+FUL 500mg (AI Failure)

Serious events: 6 serious events

Other events: 18 other events

Deaths: 10 deaths

Phase I-GSK525762 80mg+FUL 500mg (CDK4/6+AI Failure)

Serious events: 2 serious events

Other events: 11 other events

Deaths: 5 deaths

Phase II-GSK525762 +FUL

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Phase II-Placebo+FUL

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Phase I- GSK525762 60mg+FUL 500mg (AI Failure) n=33 participants at risk Participants with aromatose inhibitor (AI) failure received GSK525762 60 milligrams (mg) tablet orally once daily and Fulvestrant (FUL) 500 mg was administered intramuscularly (IM) on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure < 12M) n=12 participants at risk Participants with Cyclin-Dependent Kinase (CDK4/6)/AI failure within 12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure >=12M) n=42 participants at risk Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure >=12M Bone Only Disease n=7 participants at risk Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg+FUL 500mg (AI Failure) n=18 participants at risk Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg+FUL 500mg (CDK4/6+AI Failure) n=11 participants at risk Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase II-GSK525762 +FUL Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Tumour associated fever	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Renal and urinary disorders Acute kidney injury	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Decreased appetite	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Abdominal pain upper	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Cardiac disorders Acute coronary syndrome	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Appendicitis	3.0% 1/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Neoplasms benign, malignant and unspecified (incl cysts and polyps) B-cell lymphoma	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Catheter site haematoma	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Dehydration	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Injury, poisoning and procedural complications Diaphragmatic injury	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Diverticulitis	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Nervous system disorders Dizziness	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Electrocardiogram QT prolonged	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Extramammary Paget's disease	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Gastritis	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders General physical health deterioration	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Hepatobiliary disorders Hepatic function abnormal	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Herpes zoster	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Hypertriglyceridaemia	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Influenza	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Intestinal obstruction	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Psychiatric disorders Major depression	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Blood and lymphatic system disorders Microangiopathic haemolytic anaemia	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Cardiac disorders Myocarditis	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Nausea	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Neck pain	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Pancreatitis	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Pyrexia	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Streptococcal sepsis	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Cardiac disorders Supraventricular tachycardia	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Troponin increased	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Viral infection	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Vomiting	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.

Other adverse events

Other adverse events
Measure	Phase I- GSK525762 60mg+FUL 500mg (AI Failure) n=33 participants at risk Participants with aromatose inhibitor (AI) failure received GSK525762 60 milligrams (mg) tablet orally once daily and Fulvestrant (FUL) 500 mg was administered intramuscularly (IM) on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure < 12M) n=12 participants at risk Participants with Cyclin-Dependent Kinase (CDK4/6)/AI failure within 12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure >=12M) n=42 participants at risk Participants with CDK4/6/AI failure \>=12 months received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 60mg+FUL 500mg (CDK4/6+AI Failure >=12M Bone Only Disease n=7 participants at risk Participants with CDK4/6/AI failure \>=12 months with bone only disease received GSK525762 60 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg+FUL 500mg (AI Failure) n=18 participants at risk Participants with AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase I-GSK525762 80mg+FUL 500mg (CDK4/6+AI Failure) n=11 participants at risk Participants with CDK4/6/AI failure received GSK525762 80 mg tablet orally once daily and FUL 500 mg was administered IM on days 1, 15, 29, and once monthly thereafter.	Phase II-GSK525762 +FUL Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.	Phase II-Placebo+FUL Participants were planned to receive GSK525762+ FUL. The dose was to be decided based on the totality of the data at the end of Phase I.
Investigations Lipase increased	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 6/42 • Number of events 10 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Pain in extremity	9.1% 3/33 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.9% 5/42 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Eye disorders Dry eye	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Skin and subcutaneous tissue disorders Rash maculo-papular	3.0% 1/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Nervous system disorders Taste disorder	18.2% 6/33 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/42 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Troponin T increased	6.1% 2/33 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Upper respiratory tract infection	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	22.2% 4/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Nausea	36.4% 12/33 • Number of events 17 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	58.3% 7/12 • Number of events 10 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	71.4% 30/42 • Number of events 38 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	71.4% 5/7 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	61.1% 11/18 • Number of events 21 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	81.8% 9/11 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Fatigue	57.6% 19/33 • Number of events 24 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	33.3% 4/12 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	59.5% 25/42 • Number of events 38 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	50.0% 9/18 • Number of events 12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	63.6% 7/11 • Number of events 10 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Nervous system disorders Dysgeusia	42.4% 14/33 • Number of events 16 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	59.5% 25/42 • Number of events 30 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	57.1% 4/7 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	55.6% 10/18 • Number of events 14 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	63.6% 7/11 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Diarrhoea	39.4% 13/33 • Number of events 19 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	33.3% 4/12 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	47.6% 20/42 • Number of events 28 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	85.7% 6/7 • Number of events 10 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	55.6% 10/18 • Number of events 24 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	36.4% 4/11 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Decreased appetite	42.4% 14/33 • Number of events 18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 18/42 • Number of events 19 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	50.0% 9/18 • Number of events 15 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	54.5% 6/11 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Hyperglycaemia	39.4% 13/33 • Number of events 21 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	25.0% 3/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	38.1% 16/42 • Number of events 22 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	33.3% 6/18 • Number of events 11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Platelet count decreased	18.2% 6/33 • Number of events 25 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 12/42 • Number of events 21 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	33.3% 6/18 • Number of events 12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	36.4% 4/11 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Blood and lymphatic system disorders Anaemia	12.1% 4/33 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	35.7% 15/42 • Number of events 19 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	33.3% 6/18 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Blood bilirubin increased	15.2% 5/33 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	19.0% 8/42 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	57.1% 4/7 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	55.6% 10/18 • Number of events 20 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Respiratory, thoracic and mediastinal disorders Dyspnoea	18.2% 6/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	31.0% 13/42 • Number of events 17 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	36.4% 4/11 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Nervous system disorders Headache	18.2% 6/33 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	25.0% 3/12 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	23.8% 10/42 • Number of events 11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	38.9% 7/18 • Number of events 10 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Respiratory, thoracic and mediastinal disorders Cough	27.3% 9/33 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	31.0% 13/42 • Number of events 15 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Skin and subcutaneous tissue disorders Rash	24.2% 8/33 • Number of events 10 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	33.3% 4/12 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	23.8% 10/42 • Number of events 11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	22.2% 4/18 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Alanine aminotransferase increased	15.2% 5/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	26.2% 11/42 • Number of events 15 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.8% 5/18 • Number of events 10 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Aspartate aminotransferase increased	18.2% 6/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	25.0% 3/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	23.8% 10/42 • Number of events 12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	22.2% 4/18 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Blood and lymphatic system disorders Thrombocytopenia	24.2% 8/33 • Number of events 15 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	33.3% 4/12 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	19.0% 8/42 • Number of events 14 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	57.1% 4/7 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Vomiting	21.2% 7/33 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	19.0% 8/42 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	38.9% 7/18 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Dry mouth	24.2% 8/33 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Skin and subcutaneous tissue disorders Pruritus	18.2% 6/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 6/42 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.8% 5/18 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Constipation	9.1% 3/33 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 6/42 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	57.1% 4/7 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	36.4% 4/11 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Back pain	12.1% 4/33 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	19.0% 8/42 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Asthenia	12.1% 4/33 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 7/42 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Abdominal pain	6.1% 2/33 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Skin and subcutaneous tissue disorders Dry skin	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	19.0% 8/42 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Vascular disorders Hot flush	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	21.4% 9/42 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Musculoskeletal pain	12.1% 4/33 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Amylase increased	6.1% 2/33 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	22.2% 4/18 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Nervous system disorders Dizziness	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	19.0% 8/42 • Number of events 11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Dyspepsia	21.2% 7/33 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	22.2% 4/18 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Psychiatric disorders Insomnia	12.1% 4/33 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.9% 5/42 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Muscle spasms	18.2% 6/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Weight decreased	12.1% 4/33 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Abdominal pain upper	9.1% 3/33 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.9% 5/42 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Respiratory, thoracic and mediastinal disorders Epistaxis	12.1% 4/33 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	19.0% 8/42 • Number of events 9 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Stomatitis	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	22.2% 4/18 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Urinary tract infection	12.1% 4/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	25.0% 3/12 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	18.2% 2/11 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Infections and infestations Herpes zoster	15.2% 5/33 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Vascular disorders Hypertension	12.1% 4/33 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Arthralgia	12.1% 4/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Injury, poisoning and procedural complications Contusion	6.1% 2/33 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations International normalised ratio increased	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.9% 5/42 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	22.2% 4/18 • Number of events 8 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Gastrointestinal disorders Gastrooesophageal reflux disease	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Blood and lymphatic system disorders Neutropenia	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Chest pain	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Skin and subcutaneous tissue disorders Dermatitis acneiform	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Lymphocyte count decreased	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.9% 5/42 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Myalgia	9.1% 3/33 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 3/18 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations Neutrophil count decreased	6.1% 2/33 • Number of events 7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Bone pain	3.0% 1/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Chills	6.1% 2/33 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Flank pain	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	27.3% 3/11 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Hypertriglyceridaemia	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 6 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Hypokalaemia	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Metabolism and nutrition disorders Hyponatraemia	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	42.9% 3/7 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Injection site pain	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	16.7% 2/12 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	4.8% 2/42 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Musculoskeletal and connective tissue disorders Musculoskeletal chest pain	0.00% 0/33 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.9% 5/42 • Number of events 5 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.1% 1/11 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations N-terminal prohormone brain natriuretic peptide increased	3.0% 1/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	2.4% 1/42 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	11.1% 2/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Respiratory, thoracic and mediastinal disorders Oropharyngeal pain	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	8.3% 1/12 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	9.5% 4/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
General disorders Pyrexia	3.0% 1/33 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	14.3% 1/7 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 1 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Cardiac disorders Sinus tachycardia	6.1% 2/33 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/7 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	5.6% 1/18 • Number of events 2 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.
Investigations White blood cell count decreased	3.0% 1/33 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/12 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	7.1% 3/42 • Number of events 4 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	28.6% 2/7 • Number of events 3 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/18 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	0.00% 0/11 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.	— 0/0 • All-cause mortality, serious and non-serious adverse events were collected up to 4 year and 4 months All Treated Population consisted of participants who received at least one dose of study treatment (GSK525762 or fulvestrant). The interim analysis failed to demonstrate clinically meaningful activity, hence Phase II was not initiated. Data is presented for Phase I as data was not collected for Phase II.

Additional Information

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GlaxoSmithKline

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Principal investigator is a sponsor employee GSK agreements may vary with individual investigators, but will not prohibit any investigator from publishing. GSK supports the publication of results from all centers of a multi-center trial but requests that reports based on single-site data not precede the primary publication of the entire clinical trial
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