Trial Outcomes & Findings for Study to Evaluate the Efficacy and Safety of the Combination of Niraparib and Dostarlimab (TSR-042) in Participants With Platinum Resistant Ovarian Cancer (NCT NCT03955471)

NCT ID: NCT03955471

Last Updated: 2022-09-10

Results Overview

ORR is defined as the percentage of participants who have achieved confirmed complete response (CR) or partial response (PR), as determined by Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1) criteria based on Investigator assessment and computed tomography (CT) scans were commonly used for tumor imaging.

• Recruitment status: TERMINATED
• Study phase: PHASE2
• Target enrollment: 41 participants
• Primary outcome timeframe: Up to approximately 22 months
• Results posted on: 2022-09-10

Participant Flow

From October 2019 until September 2020, 72 participants were screened and 41 participants were enrolled (31 screen failures)

This study was terminated as the interim analysis of the primary endpoint met the prespecified futility criteria.

Participant milestones

Measure	Niraparib+Dostarlimab (TSR-042) Participants with body weight ≥77 kilogram (kg) and platelet count ≥150,000/microliter (μL) at baseline were administered Niraparib 300 milligram (mg) once daily (QD) and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until Progressive disease (PD) or toxicity. Dostarlimab (TSR-042) was administered as an intravenous (IV) infusion of 500 mg once every three weeks (Q3W) from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab (TSR-042) was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Overall Study STARTED	41
Overall Study COMPLETED	1
Overall Study NOT COMPLETED	40

Reasons for withdrawal

Measure	Niraparib+Dostarlimab (TSR-042) Participants with body weight ≥77 kilogram (kg) and platelet count ≥150,000/microliter (μL) at baseline were administered Niraparib 300 milligram (mg) once daily (QD) and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until Progressive disease (PD) or toxicity. Dostarlimab (TSR-042) was administered as an intravenous (IV) infusion of 500 mg once every three weeks (Q3W) from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab (TSR-042) was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Overall Study Death	22
Overall Study Lost to Follow-up	1
Overall Study Withdrawal by Subject	6
Overall Study Sponsor Decision to Terminate Study	11

Baseline Characteristics

Study to Evaluate the Efficacy and Safety of the Combination of Niraparib and Dostarlimab (TSR-042) in Participants With Platinum Resistant Ovarian Cancer

Baseline characteristics by cohort

Measure	Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Age, Continuous	62.9 YEARS STANDARD_DEVIATION 10.59 • n=5 Participants
Sex: Female, Male Female	41 Participants n=5 Participants
Sex: Female, Male Male	0 Participants n=5 Participants
Race/Ethnicity, Customized American Indian or Alaska Native	1 Participants n=5 Participants
Race/Ethnicity, Customized Asian	2 Participants n=5 Participants
Race/Ethnicity, Customized Black or African American	3 Participants n=5 Participants
Race/Ethnicity, Customized Unknown	3 Participants n=5 Participants
Race/Ethnicity, Customized White	32 Participants n=5 Participants

PRIMARY outcome

Timeframe: Up to approximately 22 months

Population: Safety (SAF) Population: All participants who receive any amount of study treatment.

ORR is defined as the percentage of participants who have achieved confirmed complete response (CR) or partial response (PR), as determined by Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1) criteria based on Investigator assessment and computed tomography (CT) scans were commonly used for tumor imaging.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

Objective Response Rate (ORR) in Participants With Platinum-resistant Ovarian Cancer (PROC)

7.3 Percentage of Participants Interval 1.5 to 19.9

PRIMARY outcome

Timeframe: Up to approximately 22 months

Population: Data for participants with PD-L1 positive status in the SAF population are presented.

ORR is defined as the percentage of participants who have achieved confirmed CR or PR, as determined by RECIST v1.1 criteria based on Investigator assessment and CT scans were commonly used for tumor imaging. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with combined positive score (vCPS) >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=13 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

ORR in Participants With PROC Who Have Programmed Cell Death-ligand 1 (PD-L 1) Positive Status

7.7 Percentage of Participants Interval 0.2 to 36.0

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: SAF Population. DOR has been summarized only for responders.

DOR is defined as the time from first documentation of response (CR or PR) until the time of first documentation of disease progression or death by any cause in the absence of progression by RECIST v.1.1 based on Investigator assessment.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=3 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

Duration of Response (DOR) in Participants With PROC

3.8 Months Interval 3.0 to 9.2

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data for participants with PD-L1 positive status in the SAF population are presented. DOR has been summarized only for responders.

DOR is defined as the time from first documentation of response (CR or PR) until the time of first documentation of disease progression or death by any cause in the absence of progression by RECIST v.1.1 based on Investigator assessment. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with vCPS >=5% was used as specified cut-point for the assessment of PD-L1 patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=1 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

DOR in Participants With PROC Who Have PD-L 1 Positive Status

NA Months Interval 3.8 to The Median and Upper Limit was not estimable due to low number of participants with PD-L1 positive status.

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: SAF Population

PFS is defined as the time from the date of the first dose of study treatment to the earlier date of assessment of progression or death by any cause in the absence of progression by RECIST v.1.1 based on Investigator assessment.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

Progression-free Survival (PFS) in Participants With PROC

2.1 Months Interval 1.97 to 2.23

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data for participants with PD-L1 positive status in the SAF population are presented.

PFS is defined as the time from the date of the first dose of study treatment to the earlier date of assessment of progression or death by any cause in the absence of progression by RECIST v.1.1 based on Investigator assessment. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with a vCPS >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=13 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

PFS in Participants With PROC Who Have PD-L 1 Positive Status

2.22 Months Interval 1.64 to The upper limit of the 95% CI was not estimable due to limited number of events.

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: SAF Population

OS is defined as the time from the date of the first dose of study treatment to the date of death by any cause.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

Overall Survival (OS) in Participants With PROC

10.61 Months Interval 7.26 to 13.44

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data for participants with PD-L1 positive status in the SAF population are presented.

OS is defined as the time from the date of the first dose of study treatment to the date of death by any cause. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with vCPS >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=13 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

OS in Participants With PROC Who Have PD-L 1 Positive Status

NA Months Interval 7.26 to The median and upper limit of the 95% CI was not estimable due to limited number of events.

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: SAF Population

DCR is defined as the percentage of participants who have achieved best overall response (BOR) of CR, PR, or stable disease (SD) per RECIST v.1.1 based on the investigator's assessment.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

Disease Control Rate (DCR) in Participants With PROC

29.3 Percentage of Participants Interval 16.1 to 45.5

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data for participants with PD-L1 positive status in the SAF population are presented.

DCR is defined as the percentage of participants who have achieved BOR of CR, PR, or SD per RECIST v.1.1 based on the investigator's assessment. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with vCPS >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Measure

Niraparib+Dostarlimab (TSR-042) n=13 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.

DCR in Participants With PROC Who Have PD-L 1 Positive Status

38.5 Percentage of Participants Interval 13.9 to 68.4

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination.

ORR is defined as the percentage of participants who have achieved confirmed CR or PR per RECIST v1.1 based on the independent review committee assessment.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination

ORR is defined as the percentage of participants who have achieved confirmed CR or PR per RECIST v1.1 based on the independent review committee assessment. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with a vCPS >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination

DOR is defined as the time from first documentation of response (CR or PR) until the time of first documentation of disease progression or death by any cause in the absence of progression by RECIST v.1.1 based on Independent Review Committee assessment.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination

DOR is defined as the time from first documentation of response (CR or PR) until the time of first documentation of disease progression or death by any cause in the absence of progression by RECIST v.1.1 based on Independent Review Committee assessment. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with a vCPS >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination

PFS is defined as the time from the date of the first dose of study treatment to the earlier date of assessment of progression or death by any cause in the absence of progression by RECIST v.1.1 based on Independent Review Committee Assessment.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination

PFS is defined as the time from the date of the first dose of study treatment to the earlier date of assessment of progression or death by any cause in the absence of progression by RECIST v.1.1 based on IRC Assessment. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with a vCPS >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination

DCR is defined as the percentage of participants who have achieved BOR of CR, PR, or SD per RECIST v.1.1 based on IRC Assessment.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 22 months

Population: Data was not collected as IRC assessment was not utilized due to study termination

DCR is defined as the percentage of participants who have achieved BOR of CR, PR, or SD per RECIST v.1.1 based on Independent Review Committee Assessment. PD-L1 is a ligand that binds to PD-L1 protein on tumor infiltrating T cells and renders the T cells inactive. Any PD-L1 positive tissue sample with vCPS >=5% was used as specified cut-point for the assessment of PD-L1 positive patient subset with PROC. vCPS was defined as the percentage of tumor cells and immune cells staining positive within the total tumor area.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Up to approximately 27 months

Population: SAF Population

An AE is any untoward medical occurrence in a patient administered with a medicinal product and that does which may or may not have a causal relationship with this treatment. A SAE is any untoward medical occurrence that, at any dose results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing hospitalization, results in persistent disability/incapacity, is a congenital anomaly/birth defect or any other situation according to medical or scientific judgment. TEAEs are any event that occurred between first dose of study drug up to 22 months, which were absent before treatment or that had worsened relative to pretreatment state. AESI were any AE (serious or non-serious) that is of scientific and medical concern specific to the study treatment, for which ongoing monitoring and rapid communication by the Investigator to the Sponsor was done.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Number of Participants With Adverse Events (AEs), Serious Adverse Events (SAEs), Treatment-emergent Adverse Events (TEAEs) and Adverse Event of Special Interest (AESI) AEs	41 Participants
Number of Participants With Adverse Events (AEs), Serious Adverse Events (SAEs), Treatment-emergent Adverse Events (TEAEs) and Adverse Event of Special Interest (AESI) SAEs	23 Participants
Number of Participants With Adverse Events (AEs), Serious Adverse Events (SAEs), Treatment-emergent Adverse Events (TEAEs) and Adverse Event of Special Interest (AESI) TEAE	41 Participants
Number of Participants With Adverse Events (AEs), Serious Adverse Events (SAEs), Treatment-emergent Adverse Events (TEAEs) and Adverse Event of Special Interest (AESI) AESIs	2 Participants

SECONDARY outcome

Timeframe: Up to approximately 27 months

Population: SAF Population.

Blood samples were collected for the analysis of hematology parameters and each parameter was graded according to National Cancer Institute (NCI)-Common Terminology Criteria for Adverse Events (CTCAE) version 4.3. Grade 0: Normal, Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant; Grade 4: life-threatening consequences. Baseline was defined as the most recent measurement prior to the first administration of study treatment. Data has been presented for the number of participants with hematology grade shifts from baseline grade to grade 3 and 4 for each parameter.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 0 to Grade 3	3 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 1 to Grade 3	5 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 2 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Hemoglobin, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 0 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Leukocytes, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 0 to Grade 3	5 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 1 to Grade 3	3 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 2 to Grade 3	3 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 0 to Grade 4	1 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Lymphocytes, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 0 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 0 to Grade 4	1 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Neutrophil Count, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 0 to Grade 3	4 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 1 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 0 to Grade 4	4 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Hematology Platelets, Grade 4 to Grade 4	0 Participants

SECONDARY outcome

Timeframe: Up to approximately 27 months

Population: SAF Population.

Blood samples were collected and the clinical chemistry parameters assessed were Albumin (Alb), alanine aminotransferase (ALT), amylase, aspartate aminotransferase (AST), alkaline phosphatase (ALP), sodium, total bilirubin (TB), creatinine, glucose, magnesium and potassium. The Grade shift post baseline data of each parameter from Grade 0 through Grade 4 was based on the CTCAE version 4.03, grading scale, as per intensity, namely Grade 0: Normal, Grade 1: mild; Grade 2: moderate; Grade 3: severe or medically significant; Grade 4: life-threatening consequences. Baseline was defined as the most recent measurement prior to the first administration of study treatment. Data has been presented for the number of participants with plasma chemistry grade shifts from baseline grade to grade 3 and 4 for each parameter.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 0 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 1 to Grade 3	3 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 3 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose high, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 0 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 0 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 3 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 0 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 1 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 0 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 1 to Grade 3	7 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium high, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 0 to Grade 3	3 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 0 to Grade 4	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALT, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 0 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Alb, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 0 to Grade 3	3 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 1 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 2 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 1 to Grade 4	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry ALP, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 0 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Amylase, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 0 to Grade 3	4 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 1 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry AST, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 0 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 3 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 0 to Grade 4	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 3 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry TB, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 0 to Grade 3	1 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Creatinine, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 0 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 1 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Glucose low, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 0 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium high, Grade 1 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 4 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 2 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Magnesium low, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 0 to Grade 3	3 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Potassium low, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium high, Grade 4 to Grade 4	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 0 to Grade 3	4 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 2 to Grade 3	0 Participants
Number of Participants With Grade Shift From Baseline in Plasma Chemistry Sodium low, Grade 3 to Grade 3	0 Participants

SECONDARY outcome

Timeframe: Up to approximately 27 months

Population: SAF Population

Baseline was defined as the most recent measurement prior to the first administration of study treatment. The change from baseline was calculated by subtracting the baseline values from the individual post-randomization values. The minimum (min) and maximum (max) change from baseline values have been reported.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Change From Baseline in Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) DBP, max change post baseline	10.6 Millimeters of mercury Standard Deviation 10.07
Change From Baseline in Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) DBP, min change post baseline	-5.8 Millimeters of mercury Standard Deviation 11.87
Change From Baseline in Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) SBP, max change post baseline	16.5 Millimeters of mercury Standard Deviation 23.01
Change From Baseline in Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) SBP, min change post baseline	-12.5 Millimeters of mercury Standard Deviation 24.61

SECONDARY outcome

Timeframe: Up to approximately 27 months

Population: SAF Population

Baseline was defined as the most recent measurement prior to the first administration of study treatment. The change from baseline was calculated by subtracting the baseline values from the individual post-randomization values. The minimum (min) and maximum (max) change from baseline values have been reported.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Change From Baseline in Pulse Rate max change post baseline	20.5 Beats per minute Standard Deviation 14.71
Change From Baseline in Pulse Rate min change post baseline	1 Beats per minute Standard Deviation 13.77

SECONDARY outcome

Timeframe: Up to approximately 27 months

Population: SAF Population

Baseline was defined as the most recent measurement prior to the first administration of study treatment. The change from baseline was calculated by subtracting the baseline values from the individual post-randomization values. The minimum (min) and maximum (max) change from baseline values have been reported.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=41 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Change From Baseline in Temperature max change post baseline	0.31 Degrees Celsius Standard Deviation 0.421
Change From Baseline in Temperature min change post baseline	-0.35 Degrees Celsius Standard Deviation 0.422

SECONDARY outcome

Timeframe: Baseline and up to approximately 27 months

Population: SAF Population. Only those participants with data available at the specified time points were analyzed.

Blood samples were collected to evaluate Prothrombin International Normalized Ratio (INR). Baseline was defined as the most recent measurement prior to the first administration of study treatment. Change from Baseline was calculated by subtracting Baseline value from the post-dose visit value.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=2 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Change From Baseline in Prothrombin International Normalized Ratio Day 2	0.2 Ratio
Change From Baseline in Prothrombin International Normalized Ratio Day 41	0.3 Ratio
Change From Baseline in Prothrombin International Normalized Ratio Day 52	0.7 Ratio

SECONDARY outcome

Timeframe: Baseline and up to approximately 27 months

Population: SAF Population. Only those participants with data available at the specified time points were analyzed.

Blood samples were planned to be collected to evaluate activated partial thromboplastin time (APTT). Baseline was defined as the most recent measurement prior to the first administration of study treatment. Change from Baseline was calculated by subtracting Baseline value from the post-dose visit value.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=1 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Change in Baseline in Activated Partial Thromboplastin Time Day 2	1 Second
Change in Baseline in Activated Partial Thromboplastin Time Day 41	16.9 Second

SECONDARY outcome

Timeframe: Baseline and up to approximately 27 months

Population: SAF Population. Only those participants with data available at the specified time points were analyzed.

Blood samples were collected to evaluate thyrotropin at indicated time points. Baseline was defined as the most recent measurement prior to the first administration of study treatment. Change from Baseline was calculated by subtracting Baseline value from the post-dose visit value.

Outcome measures

Measure	Niraparib+Dostarlimab (TSR-042) n=15 Participants Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Change From Baseline in Thyrotropin Cycle 5 Day 1	8.074 Milliunits per liter (mU/L) Standard Deviation 19.737
Change From Baseline in Thyrotropin Cycle 7 Day 1	12.79 Milliunits per liter (mU/L) Standard Deviation 23.240
Change From Baseline in Thyrotropin Cycle 9 Day 1	2.596 Milliunits per liter (mU/L)
Change From Baseline in Thyrotropin Cycle 11 Day 1	2.517 Milliunits per liter (mU/L)

Adverse Events

Niraparib+Dostarlimab (TSR-042)

Serious events: 23 serious events

Other events: 41 other events

Deaths: 22 deaths

Serious adverse events

Measure	Niraparib+Dostarlimab (TSR-042) n=41 participants at risk Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Blood and lymphatic system disorders Thrombocytopenia	7.3% 3/41 • Number of events 3 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Blood and lymphatic system disorders Anaemia	4.9% 2/41 • Number of events 2 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Cardiac disorders Tachycardia	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Small intestinal obstruction	7.3% 3/41 • Number of events 3 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Intestinal obstruction	4.9% 2/41 • Number of events 2 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Vomiting	4.9% 2/41 • Number of events 2 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Abdominal pain	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Diarrhoea	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Ileus paralytic	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Nausea	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
General disorders Asthenia	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
General disorders Pyrexia	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Infections and infestations Pneumonia	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Blood bilirubin increased	4.9% 2/41 • Number of events 2 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Alanine aminotransferase increased	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Platelet count decreased	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Dehydration	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Diabetic ketoacidosis	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Malnutrition	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Musculoskeletal and connective tissue disorders Back pain	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Squamous cell carcinoma	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Nervous system disorders Seizure	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Renal and urinary disorders Acute kidney injury	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Renal and urinary disorders Renal failure	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Respiratory, thoracic and mediastinal disorders Dyspnoea	7.3% 3/41 • Number of events 3 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Respiratory, thoracic and mediastinal disorders Pleural effusion	4.9% 2/41 • Number of events 2 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Respiratory, thoracic and mediastinal disorders Pneumothorax	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Respiratory, thoracic and mediastinal disorders Tachypnoea	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Vascular disorders Embolism	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Vascular disorders Hypertension	2.4% 1/41 • Number of events 1 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.

Other adverse events

Measure	Niraparib+Dostarlimab (TSR-042) n=41 participants at risk Participants with body weight ≥77 kg and platelet count ≥150,000/μL at baseline were administered Niraparib 300 mg QD and participants with body weight \<77 kg or platelet count \<150,000/μL at baseline were administered Niraparib 200 mg QD. Niraparib was administered continuously until PD or toxicity. Dostarlimab (TSR-042) was administered as an IV infusion of 500 mg Q3W from Cycle 1 Day 1 through Cycle 4. Beginning at Cycle 5, Dostarlimab was administered via an IV infusion of 1000 mg on Day 1 of each 6-week cycle until PD or toxicity, up to 27 months.
Blood and lymphatic system disorders Anaemia	43.9% 18/41 • Number of events 63 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Blood and lymphatic system disorders Thrombocytopenia	17.1% 7/41 • Number of events 11 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Cardiac disorders Palpitations	12.2% 5/41 • Number of events 5 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Cardiac disorders Sinus tachycardia	9.8% 4/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Cardiac disorders Tachycardia	7.3% 3/41 • Number of events 3 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Endocrine disorders Hypothyroidism	14.6% 6/41 • Number of events 7 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Nausea	58.5% 24/41 • Number of events 35 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Vomiting	46.3% 19/41 • Number of events 28 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Abdominal pain	36.6% 15/41 • Number of events 24 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Constipation	36.6% 15/41 • Number of events 18 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Diarrhoea	26.8% 11/41 • Number of events 14 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Abdominal distension	22.0% 9/41 • Number of events 11 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Dyspepsia	12.2% 5/41 • Number of events 6 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Ascites	9.8% 4/41 • Number of events 5 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Dry mouth	12.2% 5/41 • Number of events 5 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Gastrooesophageal reflux disease	9.8% 4/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Gastrointestinal disorders Stomatitis	7.3% 3/41 • Number of events 3 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
General disorders Fatigue	43.9% 18/41 • Number of events 25 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
General disorders Oedema peripheral	17.1% 7/41 • Number of events 8 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
General disorders Pyrexia	9.8% 4/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Infections and infestations Urinary tract infection	9.8% 4/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Blood creatinine increased	24.4% 10/41 • Number of events 21 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Platelet count decreased	26.8% 11/41 • Number of events 18 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Blood alkaline phosphatase increased	24.4% 10/41 • Number of events 17 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Aspartate aminotransferase increased	19.5% 8/41 • Number of events 14 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Alanine aminotransferase increased	14.6% 6/41 • Number of events 12 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Investigations Neutrophil count decreased	12.2% 5/41 • Number of events 6 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Hyponatraemia	19.5% 8/41 • Number of events 15 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Decreased appetite	22.0% 9/41 • Number of events 12 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Hypomagnesaemia	17.1% 7/41 • Number of events 11 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Hypoalbuminaemia	7.3% 3/41 • Number of events 8 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Hyperglycaemia	9.8% 4/41 • Number of events 6 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Metabolism and nutrition disorders Hypokalaemia	9.8% 4/41 • Number of events 6 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Musculoskeletal and connective tissue disorders Back pain	7.3% 3/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Musculoskeletal and connective tissue disorders Myalgia	9.8% 4/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Nervous system disorders Headache	12.2% 5/41 • Number of events 6 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Nervous system disorders Dysgeusia	12.2% 5/41 • Number of events 5 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Psychiatric disorders Insomnia	14.6% 6/41 • Number of events 7 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Psychiatric disorders Anxiety	7.3% 3/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Respiratory, thoracic and mediastinal disorders Dyspnoea	22.0% 9/41 • Number of events 11 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Respiratory, thoracic and mediastinal disorders Cough	9.8% 4/41 • Number of events 4 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Respiratory, thoracic and mediastinal disorders Pleural effusion	7.3% 3/41 • Number of events 3 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Skin and subcutaneous tissue disorders Rash maculo-papular	9.8% 4/41 • Number of events 12 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Skin and subcutaneous tissue disorders Rash	12.2% 5/41 • Number of events 5 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.
Vascular disorders Hypertension	24.4% 10/41 • Number of events 13 • All cause mortality, non-SAEs and SAEs were collected from Day 1 up to approximately 27 months.

Additional Information

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Results disclosure agreements

• 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.
• Publication restrictions are in place

Restriction type: OTHER