Study of Olaparib Plus Pembrolizumab Versus Chemotherapy Plus Pembrolizumab After Induction With First-Line Chemotherapy Plus Pembrolizumab in Triple Negative Breast Cancer (TNBC) (MK-7339-009/KEYLYNK-009)

PFS was defined as the time from randomization to the first documented progressive disease (PD) per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR), or death due to any cause, whichever occurs first. Per RECIST 1.1, PD was defined as ≥20% increase in the sum of diameters (SOD) of target lesions. In addition to the relative increase of 20%, the sum had to demonstrate an absolute increase of ≥5 mm. The appearance of one or more new lesions was also considered PD. Only participants with a CPS ≥10 were included in this analysis. PFS is reported based on the product-limit (Kaplan-Meier) method for censored data.

OS was defined as the time from randomization to death due to any cause. Participants without documented death at the time of the final analysis were censored at the date of the last follow-up. Only participants with a CPS ≥10 were included in this analysis.

PFS was defined as the time from randomization to the first documented progressive disease (PD) per Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST 1.1) as Assessed by Blinded Independent Central Review (BICR), or death due to any cause, whichever occurs first. Per RECIST 1.1, PD was defined as ≥20% increase in the sum of diameters (SOD) of target lesions. In addition to the relative increase of 20%, the sum had to demonstrate an absolute increase of ≥5 mm. The appearance of one or more new lesions was also considered PD. Only participants with BRCAm-positive tumors were included in this analysis. PFS is reported based on the product-limit (Kaplan-Meier) method for censored data.

OS was defined as the time from randomization to death due to any cause. Participants without documented death at the time of the final analysis were censored at the date of the last follow-up. Only participants with BRCAm-positive tumors were included in this analysis.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to the Global Health Status (GHS) question "How would you rate your overall health during the past week?" (Item 29) and the QoL question "How would you rate your overall quality of life during the past week?" (Item 30) were each scored on a 7-point scale (1=Very Poor to 7=Excellent), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. Change from baseline in EORTC QLQ-C30 Items 29 and 30 combined scores was calculated based on a constrained longitudinal data analysis (cLDA) model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1) and BRCA status at randomization (BRCAm vs. BRCAwt)) as covariates.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 5 questions about their physical functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. The change from baseline in physical functioning (EORTC QLQ-C30 Items 1-5) score was calculated based on a cLDA model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1) and BRCA status at randomization (BRCAm vs. BRCAwt)) as covariates.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 4 questions about their emotional functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. Change from baseline in emotional functioning (EORTC QLQ-C30 Items 21-24) score was calculated based on a cLDA model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1) and BRCA status at randomization (BRCAm vs. BRCAwt)) as covariates.

EORTC-QLQ-BR23 is a 23-item breast cancer-specific companion module to the EORTC-QLQ-C30, consisting of functional scales (body image, sexual enjoyment, sexual functioning, future perspective) and symptom scales (systemic therapy side effects, upset by hair loss, arm symptoms, breast symptoms). Participant responses to 7 questions about their systemic therapy side effects are scored on a 4-point scale (1=Not at All, 4=Very Much). Using linear transformation, raw scores are standardized, so scores range from 0 to 100. A higher score indicates a better quality of life. The change from baseline in systemic therapy side effects (EORTC QLQ-BR23 Items 1-4, 6, 7, and 8) score was calculated based on a cLDA model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1) and BRCA status at randomization (BRCAm vs. BRCAwt)) as covariates.

The EQ-5D-5L is a questionnaire developed to assess health-related outcomes. The VAS is a component of the EQ-5D-5L that asks participants to rate their overall health on a vertical visual analogue scale, with the scale's ends labelled 'The best health you can imagine' (equivalent to a score of 0) and 'The worst health you can imagine' (equivalent to a score of 100). The change from baseline in VAS score was calculated based on a cLDA model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1) and BRCA status at randomization (BRCAm vs. BRCAwt)) as covariates.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to the Global Health Status (GHS) question "How would you rate your overall health during the past week?" (Item 29) and the QoL question "How would you rate your overall quality of life during the past week?" (Item 30) were each scored on a 7-point scale (1=Very Poor to 7=Excellent), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. The change from baseline in EORTC QLQ-C30 Items 29 and 30 scores was calculated based on a constrained longitudinal data analysis (cLDA) model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), and baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1)) as covariates.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 5 questions about their physical functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. The change from baseline in physical functioning (EORTC QLQ-C30 Items 1-5) score was calculated based on a constrained longitudinal data analysis (cLDA) model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), and baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1)) as covariates.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 4 questions about their emotional functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. The change from baseline in emotional functioning (EORTC QLQ-C30 Items 21-24) score was calculated based on a cLDA model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), and baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1)) as covariates.

EORTC-QLQ-BR23 is a 23-item breast cancer-specific companion module to the EORTC-QLQ-C30, consisting of functional scales (body image, sexual enjoyment, sexual functioning, future perspective) and symptom scales (systemic therapy side effects, upset by hair loss, arm symptoms, breast symptoms). Participant responses to 7 questions about their systemic therapy side effects are scored on a 4-point scale (1=Not at All, 4=Very Much). Using linear transformation, raw scores are standardized, so scores range from 0 to 100. A higher score indicates a better quality of life. The change from baseline in systemic therapy side effects (EORTC QLQ-BR23 Items 1-4, 6, 7, and 8) score was calculated based on a cLDA model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), and baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1)) as covariates.

The EQ-5D-5L is a questionnaire developed to assess health-related outcomes. The VAS is a component of the EQ-5D-5L that asks participants to rate their overall health on a vertical visual analogue scale, with the scale's ends labelled 'The best health you can imagine' (equivalent to a score of 0) and 'The worst health you can imagine' (equivalent to a score of 100). The change from baseline in VAS score was calculated based on a cLDA model with scores as response variable with covariates for treatment by time interaction, stratification factors (response at randomization (CR/PR vs. SD), and baseline CPS for PD-L1 expression (PD-L1 CPS<1 vs. PD-L1 CPS≥1)) as covariates.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to the Global Health Status (GHS) question "How would you rate your overall health during the past week?" (Item 29) and the QoL question "How would you rate your overall quality of life during the past week?" (Item 30) were each scored on a 7-point scale (1=Very Poor to 7=Excellent), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in Items 29 and 30 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 5 questions about their physical functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in physical functioning Items 1 to 5 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 4 questions about their emotional functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in emotional functioning Items 21-24 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

EORTC-QLQ-BR23 is a 23-item breast cancer-specific companion module to the EORTC-QLQ-C30 and consists of four functional scales (body image, sexual enjoyment, sexual functioning, future perspective) and four symptom scales (systemic therapy side effects, upset by hair loss, arm symptoms, breast symptoms). Participant responses to 7 questions about their systemic therapy side effects are scored on a 4-point scale (1=Not at All to 4=Very Much). Using linear transformation, raw scores are standardized, so that scores range from 0 to 100. A higher score indicates a better quality of life. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in systemic therapy side effects Items 1-4, 6, 7 and 8 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to the Global Health Status (GHS) question "How would you rate your overall health during the past week?" (Item 29) and the QoL question "How would you rate your overall quality of life during the past week?" (Item 30) were each scored on a 7-point scale (1=Very Poor to 7=Excellent), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in Items 29 and 30 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 5 questions about their physical functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in physical functioning Items 1 to 5 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

EORTC QLQ-C30 is a 30-item questionnaire developed to assess the QoL of cancer patients. Participant responses to 4 questions about their emotional functioning are scored on a 4-point scale (1=Not at All to 4=Very Much), then summed. Summed raw scores were standardized by linear transformation so that scores ranged from 0 to 100, with a higher score indicating a better overall outcome. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in emotional functioning Items 21-24 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

EORTC-QLQ-BR23 is a 23-item breast cancer-specific companion module to the EORTC-QLQ-C30 and consists of four functional scales (body image, sexual enjoyment, sexual functioning, future perspective) and four symptom scales (systemic therapy side effects, upset by hair loss, arm symptoms, breast symptoms). Participant responses to 7 questions about their systemic therapy side effects are scored on a 4-point scale (1=Not at All to 4=Very Much). Using linear transformation, raw scores are standardized, so that scores range from 0 to 100. A higher score indicates a better quality of life. TTD was defined as the time from baseline to the first onset of a ≥10-point decrease with confirmation by the subsequent visit of a ≥10-point decrease in systemic therapy side effects Items 1-4, 6, 7 and 8 scale scores. TTD is reported based on the product-limit (Kaplan-Meier) method for censored data.

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The number of participants who experience at least 1 AE is presented.

An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention. The number of participants who discontinued study treatment due to an AE is presented.