Trial Outcomes & Findings for PD 0332991 and Anastrozole for Stage 2 or 3 Estrogen Receptor Positive and HER2 Negative Breast Cancer (NCT NCT01723774)

NCT ID: NCT01723774

Last Updated: 2025-12-09

Results Overview

Complete cell cycle arrest is defined as Ki67 ≤ 2.7% following 2 weeks of neoadjuvant PD 0332991

Recruitment status

ACTIVE_NOT_RECRUITING

Study phase

PHASE2

Target enrollment

84 participants

Primary outcome timeframe

At cycle 1 day 15 (2 weeks)

Results posted on

2025-12-09

Participant Flow

Participant milestones

Participant milestones
Measure	Arm 1: PIK3CA Wild Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Adjuvant Continuation Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Neoadjuvant STARTED	34	16	34	0
Neoadjuvant COMPLETED	27	12	21	0
Neoadjuvant NOT COMPLETED	7	4	13	0
Adjuvant STARTED	0	0	0	7
Adjuvant COMPLETED	0	0	0	7
Adjuvant NOT COMPLETED	0	0	0	0

Reasons for withdrawal

Reasons for withdrawal
Measure	Arm 1: PIK3CA Wild Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Neoadjuvant Ki67 > 10%	4	0	10
Neoadjuvant Withdrawal by Subject	3	1	0
Neoadjuvant Disease progression	0	1	1
Neoadjuvant Adverse Event	0	1	2
Neoadjuvant High estradiol	0	1	0

Baseline Characteristics

PD 0332991 and Anastrozole for Stage 2 or 3 Estrogen Receptor Positive and HER2 Negative Breast Cancer

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Arm 1: PIK3CA Wild Type Cohort n=34 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=16 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=34 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Total n=84 Participants Total of all reporting groups
Age, Continuous	58 years n=4 Participants	55 years n=50 Participants	53 years n=518 Participants	55.5 years n=175 Participants
Sex: Female, Male Female	34 Participants n=4 Participants	16 Participants n=50 Participants	34 Participants n=518 Participants	84 Participants n=175 Participants
Sex: Female, Male Male	0 Participants n=4 Participants	0 Participants n=50 Participants	0 Participants n=518 Participants	0 Participants n=175 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	0 Participants n=4 Participants	0 Participants n=50 Participants	5 Participants n=518 Participants	5 Participants n=175 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	34 Participants n=4 Participants	15 Participants n=50 Participants	28 Participants n=518 Participants	77 Participants n=175 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=4 Participants	1 Participants n=50 Participants	1 Participants n=518 Participants	2 Participants n=175 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=4 Participants	0 Participants n=50 Participants	2 Participants n=518 Participants	2 Participants n=175 Participants
Race (NIH/OMB) Asian	0 Participants n=4 Participants	0 Participants n=50 Participants	1 Participants n=518 Participants	1 Participants n=175 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=4 Participants	0 Participants n=50 Participants	0 Participants n=518 Participants	0 Participants n=175 Participants
Race (NIH/OMB) Black or African American	3 Participants n=4 Participants	0 Participants n=50 Participants	3 Participants n=518 Participants	6 Participants n=175 Participants
Race (NIH/OMB) White	30 Participants n=4 Participants	16 Participants n=50 Participants	24 Participants n=518 Participants	70 Participants n=175 Participants
Race (NIH/OMB) More than one race	1 Participants n=4 Participants	0 Participants n=50 Participants	0 Participants n=518 Participants	1 Participants n=175 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=4 Participants	0 Participants n=50 Participants	4 Participants n=518 Participants	4 Participants n=175 Participants
Region of Enrollment United States	34 participants n=4 Participants	16 participants n=50 Participants	34 participants n=518 Participants	84 participants n=175 Participants

PRIMARY outcome

Timeframe: At cycle 1 day 15 (2 weeks)

Population: Arm 2 and Arm 3 participants were not evaluable for this outcome measure as it is for Arm 1: PIK3CA Wild Type Cohort only. 5 participants in Arm 1 were not evaluable. 1 participant was not evaluable due to insufficient quality of specimen, 1 participant was not evaluable because she withdrew prior to starting treatment, 2 participants were not evaluable because there was no tumor present on biopsy, and 1 participant was not evaluable because she withdrew prior to cycle 1 day 15 biopsy.

Complete cell cycle arrest is defined as Ki67 ≤ 2.7% following 2 weeks of neoadjuvant PD 0332991

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=29 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Number of Participants With Complete Cell Cycle Arrest at Cycle 1 Day 15 (PIK3CA Wild Type Cohort Only)	23 Participants	—	—

PRIMARY outcome

Timeframe: At cycle 1 day 15 (2 weeks)

Population: Arm 1 and Arm 2 participants were not evaluable for this outcome measure as it is for Arm 3: Endocrine Resistant Cohort only. 1 participant was not evaluable for this outcome measure as the participant did not have any tissue available at the cycle 1 day 15 biopsy.

Complete cell cycle arrest is defined as Ki67 ≤ 2.7% following 2 weeks of neoadjuvant PD 0332991

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=33 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Number of Participants With Complete Cell Cycle Arrest at Cycle 1 Day 15 (Endocrine Resistant Cohort Only)	—	—	19 Participants

SECONDARY outcome

Timeframe: At cycle 1 day 15 (2 weeks)

Population: Arm 1 and Arm 3 participants were not evaluable for this outcome measure as it is for Arm 2: PIK3CA Mutant Type Cohort only.

Complete cell cycle arrest is defined as Ki67 ≤ 2.7% following 2 weeks of neoadjuvant PD 0332991

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=16 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Number of Participants With Complete Cell Cycle Arrest at Cycle 1 Day 15 ( PIK3CA Mutant Type Cohort Only)	—	16 Participants	—

SECONDARY outcome

Timeframe: Cycle 1 day 1 and cycle 1 day 15 (2 weeks)

Population: PIK3CA Wild Type Cohort - 5 participants not evaluable. 1 due to insufficient quality of specimen, 1 because she withdrew prior to starting treatment, 2 participants because there was no tumor present on biopsy, and 1 because she withdrew prior to cycle 1 day 15 biopsy. Endocrine Resistant Cohort-1 participant because no tissue available at the cycle 1 day 15 biopsy.

Compare rate of complete cell cycle arrest (defined as Ki67 ≤ 2.7%) arrest between C1D1 and C1D15

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=29 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=16 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=33 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Number of Participants With Complete Cell Cycle Arrest Cycle 1 Day 15 complete cell cycle arrest	23 Participants	16 Participants	19 Participants
Number of Participants With Complete Cell Cycle Arrest Cycle 1 Day 1 complete cell cycle arrest	8 Participants	4 Participants	0 Participants

SECONDARY outcome

Timeframe: 16 weeks

Population: 7 participants in Arm 1 were not evaluable for this outcome measure. 3 participants in Arm 2 were not evaluable for this outcome measure. 12 participants in Arm 3 were not evaluable for this outcome measure. Reasons include patient withdrawal (n=4), progressive disease during cycle 1 (n=2), cycle 1 day 15 Ki67 \>10% (n=14) high estradiol (n=1), and adverse event (n=1).

* The clinical response rate is the number of patients whose disease meets the WHO criteria of complete or partial response prior to surgery divided by the total number of eligible patients who began combination neoadjuvant treatment. * Complete Response (CR) is defined as the disappearance of all known disease based on a comparison between the pre-treatment measurements and the measurements taken at the completion of neo-adjuvant therapy (that is, at the end of cycle 4 neo-adjuvant combination therapy). In addition there is no appearance of new lesions. * Partial Response (PR) is defined as a 50% or greater decrease in the product of the bidimensional measurements of the lesion (total tumor size) between the pre-treatment measurements and the measurements taken at the completion of neo-adjuvant therapy (that is, at the end of cycle 4 neo-adjuvant combination therapy). In addition there can be no appearance of new lesions or progression of any lesion.

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=27 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=13 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=22 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Clinical Response Rate	21 Participants	10 Participants	16 Participants

SECONDARY outcome

Timeframe: At the end of cycle 4 prior to surgery (estimated to be 16 weeks)

Population: Arm 1 PIK3CA Wild Type Cohort: 23 participants not evaluable due to imaging not being performed. Arm 2 PIK3CA Mutant Type Cohort: 9 participants not evaluable due to imaging not being performed. Arm 3 Endocrine Resistant Cohort: 10 participants not evaluable due to imaging not being performed.

* The radiological response rate is the number of patients whose disease meets with WHO criteria for complete or partial response at the evaluation prior to surgery divided by the total number of eligible patients who began combination neo-adjuvant therapy. * Complete Response (CR) is defined as the disappearance of all known disease based on a comparison between the pre-treatment measurements and the measurements taken at the completion of neo-adjuvant therapy (that is, at the end of cycle 4 neo-adjuvant combination therapy). In addition there is no appearance of new lesions. * Partial Response (PR) is defined as a 50% or greater decrease in the product of the bidimensional measurements of the lesion (total tumor size) between the pre-treatment measurements and the measurements taken at the completion of neo-adjuvant therapy (that is, at the end of cycle 4 neo-adjuvant combination therapy). In addition there can be no appearance of new lesions or progression of any lesion.

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=11 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=7 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=10 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Radiologic Response Rate	7 Participants	3 Participants	6 Participants

SECONDARY outcome

Timeframe: From start of treatment through 30 days after completion of an estimated 4 months of neoadjuvant therapy

The maximum grade for each type of adverse event will be recorded for each patient using the NCI-CTCAE v4.0 coding scheme, and frequency tables will be reviewed to determine patterns. Additionally, the relationship (possibly related, probably related, and definitely related) of the adverse event(s) to the study treatment will be taken into consideration.

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=34 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=16 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=34 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 weight loss	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 allergic rhinitis	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 anemia	4 Participants	5 Participants	7 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 dry eye	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 constipation	4 Participants	3 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 diarrhea	4 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 dry mouth	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 dyspepsia	1 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 flatulence	1 Participants	1 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 gastroesophageal reflux disease	0 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 gastrointestinal pain	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 mucositis oral	9 Participants	3 Participants	3 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 nausea	8 Participants	3 Participants	10 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 oral pain	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 rectal pain	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 stomatitis	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 vomiting	0 Participants	0 Participants	2 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 chills	2 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 edema limbs	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 fatigue	15 Participants	8 Participants	6 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 fever	3 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 localized edema	0 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 pain	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 shingles	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 sinusitis	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 urinary tract infection	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 seroma	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 alanine aminotransferase increased	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 3/4 alanine aminotransferase increased	1 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 aspartate aminotransferase increased	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 3/4 aspartate aminotransferase increased	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 lymphocyte count decreased	3 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 neutrophil count decreased	14 Participants	4 Participants	12 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 3/4 neutrophil count decreased	7 Participants	6 Participants	13 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 platelet count decreased	6 Participants	5 Participants	3 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 white blood cell decreased	23 Participants	6 Participants	11 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 3/4 white blood cell decreased	0 Participants	1 Participants	2 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 anorexia	2 Participants	3 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 hypocalcemia	3 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 hypokalemia	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 hyponatremia	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 arthralgia	5 Participants	4 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 back pain	2 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 bone pain	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 myalgia	2 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 osteoporosis	0 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 dizziness	3 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 dysgeusia	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 headache	5 Participants	0 Participants	2 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 memory impairment	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 peripheral motor neuropathy	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 peripheral sensory neuropathy	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 confusion	0 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 depression	2 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 insomnia	2 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 pelvic pain	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 cough	2 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 dyspnea	0 Participants	1 Participants	2 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 epistaxis	1 Participants	1 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 nasal congestion	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 postnasal drip	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 sore throat	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 alopecia	1 Participants	4 Participants	2 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 dry skin	2 Participants	1 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 hyperhidrosis	2 Participants	2 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 papulopustular rash	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 pruritus	1 Participants	1 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 rash maculo-papular	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 3/4 rash maculo-papular	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 fever blister	1 Participants	0 Participants	0 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 itching	0 Participants	0 Participants	1 Participants
Safety of PD 0332991 in Combination in Anastrozole as Measured by Frequency and Grade of Related Adverse Events Grade 1/2 hot flashes	10 Participants	7 Participants	3 Participants

SECONDARY outcome

Timeframe: At the time of surgery (estimated to be 5 months)

Population: Some participants were not evaluable for this outcome measure due to participant withdrawal and surgery not completed.

* Preoperative endocrine prognostic index (PEPI) score is derived from four factors assigned a numerical score following neoadjuvant endocrine therapy, including Ki67 expression in the surgical specimen, pathologic tumor size (indicated as "T" below), lymph node status (indicated as "N" below), and estrogen receptor (ER) level (indicated as ER Allred below). * PEPI-0 score indicates T1 or T2, N0, Ki67 \< 2.7%, ER Allred \> 2. * It predicts a low risk of recurrence.

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=32 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=14 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=31 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Number of Participants With a PEPI-0 Score	3 Participants	2 Participants	1 Participants

SECONDARY outcome

Timeframe: Pre-treatment and cycle 1 day 15

Population: Only participants who had tissue available at the two time points were evaluable for this outcome measure.

To assess Ki67 level on serially collected tumor specimens

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=28 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=16 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=33 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Change in Ki67 Level of Tumor Specimens Pre-treatment	29.75 percentage of Ki67 in tumor sample Interval 3.63 to 74.0	19.76 percentage of Ki67 in tumor sample Interval 2.67 to 44.5	33.52 percentage of Ki67 in tumor sample Interval 7.48 to 94.25
Change in Ki67 Level of Tumor Specimens Cycle 1 Day 15	8.18 percentage of Ki67 in tumor sample Interval 0.0 to 80.0	0.51 percentage of Ki67 in tumor sample Interval 0.0 to 1.97	15.27 percentage of Ki67 in tumor sample Interval 0.0 to 97.87

SECONDARY outcome

Timeframe: Cycle 1 day 15 and at time of surgery (approximately 2-4 weeks post completion of cycle 4 - each cycle is 28 days)

Population: Only participants who had tissue available at the two time points were evaluable for this outcome measure.

To assess Ki67 level on serially collected tumor specimens

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=19 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=13 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=12 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Change in Ki67 Level of Tumor Specimens Cycle 1 Day 15	11.70 percentage of Ki67 in tumor sample Interval 0.0 to 80.0	0.51 percentage of Ki67 in tumor sample Interval 0.0 to 1.97	0.97 percentage of Ki67 in tumor sample Interval 0.0 to 6.0
Change in Ki67 Level of Tumor Specimens At time of surgery	23.00 percentage of Ki67 in tumor sample Interval 1.91 to 75.63	8.75 percentage of Ki67 in tumor sample Interval 0.13 to 74.16	2.84 percentage of Ki67 in tumor sample Interval 0.0 to 12.0

SECONDARY outcome

Timeframe: At the time of surgery (estimated to be 5 months)

-A pathologic complete response is defined as no histology evidence of invasive tumor cells in the surgical breast specimen and sentinel or axillary lymph nodes.

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=34 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=16 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=34 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Number of Participants With Pathologic Complete Response (pCR)	0 Participants	0 Participants	0 Participants

SECONDARY outcome

Timeframe: From start of adjuvant therapy through 30 days after completion of adjuvant therapy (estimated to be 2 years)

Outcome measures

Outcome measures
Measure	Arm 1: PIK3CA Wild Type Cohort n=7 Participants * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 anemia	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 blurred vision	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 watering eyes	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 diarrhea	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 gastritis	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 mucositis oral	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 nausea	2 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 vomiting	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 fatigue	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 upper respiratory infection	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 bruising	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 aspartate aminotransferase increased	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 lymphocyte count decreased	3 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 3/4 lymphocyte count decreased	2 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 neutrophil count decreased	2 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 3/4 neutrophil count decreased	3 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 platelet count decreased	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 white blood cell count decreased	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 3/4 white blood cell count decreased	2 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 hyperglycemia	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 arthralgia	1 Participants	—	—
Safety Profile of Study Therapy During Adjuvant Therapy as Measured by Frequency and Grade of Adverse Event Grade 1/2 alopecia	2 Participants	—	—

SECONDARY outcome

Timeframe: 5 years

Outcome measures

Outcome data not reported

Serious events: 1 serious events

Other events: 16 other events

Deaths: 0 deaths

Arm 3: Endocrine Resistant Cohort

Serious events: 1 serious events

Other events: 34 other events

Deaths: 4 deaths

Adjuvant Continuation

Serious events: 1 serious events

Other events: 7 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Arm 1: PIK3CA Wild Type Cohort n=34 participants at risk * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 2: PIK3CA Mutant Type Cohort n=16 participants at risk * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycle 0 is 28 days of anastrozole PO daily and, if premenopausal, goserelin SC every 28 days. * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Arm 3: Endocrine Resistant Cohort n=34 participants at risk * Tumor biopsy for testing/research at baseline and Cycle 1 Day 15 * Cycles 1-5: PD 0332991 combined with anastrozole (and goserelin if premenopausal) is to be (4) 28-day cycles followed by a 5th cycle of 10-12 days duration consisting of daily PD 0332991 and anastrozole (last dose day before surgery) * Standard surgery will be performed per institutional standards 2-4 weeks following the completion of Cycle 4 in those who did not receive Cycle 5. In patients who receive Cycle 5, surgery occurs on Day 11, 12, or 13 of Cycle 5. * Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.	Adjuvant Continuation n=7 participants at risk Patients who derived benefit from the therapy have the option of taking PD 0332991 in combination with endocrine therapy for 23 cycles after surgery and adjuvant chemotherapy and radiation if indicated. It should be re-started at least 4 weeks after the completion of chemotherapy and radiation therapy if these treatments were planned.
Gastrointestinal disorders Abdominal pain	0.00% 0/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/16 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	14.3% 1/7 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).
Hepatobiliary disorders Cholecystitis	2.9% 1/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/16 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/7 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).
Infections and infestations Febrile neutropenia	0.00% 0/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	6.2% 1/16 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/7 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).
Infections and infestations Pneumonitis	0.00% 0/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/16 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	2.9% 1/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/7 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).
Investigations Neutrophil count decrease	2.9% 1/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/16 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/34 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).	0.00% 0/7 • Adverse events were collected from start of treatment until 30 days following the last day of study treatment. Median treatment length of 122.5 days (full range 5-1615 days).

Other adverse events

Additional Information

Cynthia X. Ma, M.D., Ph.D.

Washington University School of Medicine

Phone: 314-362-9383

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place