A Study of Rucaparib Versus Physician's Choice of Therapy in Participants With Metastatic Castration-resistant Prostate Cancer and Homologous Recombination Gene Deficiency

The primary efficacy endpoint for the study is rPFSirr, defined as the time from randomization to the first objective evidence of radiographic progression, or death due to any cause (whichever occurs first).

Radiographic disease progression includes confirmed soft tissue disease progression and confirmed bone disease progression as per modified RECIST Version 1.1 (at least a 20% increase in the sum of the LD of target lesions or appearance of one or more new extra-skeletal lesions and/or unequivocal progression of existing nontarget lesions) or PCWG3 criteria Progression by bone is determined by PCWG3 criteria in which at least two new lesions appearing during the first 12-week flare window followed by 2 additional new lesions in the confirmatory scan appearing after the 12-week flare window, or after the 12-week flare window, at least 2 new lesions relative to the first post-treatment scan confirmed on a subsequent scan).

The primary efficacy endpoint for the study is rPFSirr, defined as the time from randomization to the first objective evidence of radiographic progression, or death due to any cause (whichever occurs first).

Radiographic disease progression includes confirmed soft tissue disease progression and confirmed bone disease progression as per modified RECIST Version 1.1 (at least a 20% increase in the sum of the LD of target lesions or appearance of one or more new extra-skeletal lesions and/or unequivocal progression of existing nontarget lesions) or PCWG3 criteria (Progression by bone is determined by PCWG3 criteria in which at least two new lesions appearing during the first 12-week flare window followed by 2 additional new lesions in the confirmatory scan appearing after the 12-week flare window, or after the 12-week flare window, at least 2 new lesions relative to the first post-treatment scan confirmed on a subsequent scan).

Overall survival time is calculated as the time from randomization to death (by any cause) +1 day. Participants who have not died will be censored on the date the participant was last known to be alive.

Overall survival time is calculated as the time from randomization to death (by any cause) +1 day. Participants who have not died will be censored on the date the participants was last known to be alive.

ORR is defined as the percentage of participants with a confirmed best response of Complete response (CR) or Partial Response (PR) in participants with measurable disease at study entry. Modified RECIST Version 1.1 criteria is used to determine ORR (ie, CR or PR by IRR assessment and no progression in bone per PCWG3 by IRR assessment).

CR is disappearance of all target and non-target lesions; any pathological lymph nodes (whether target or non-target) must have reduction in short axis to <10 mm. PR is at least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum of diameters.

ORR is defined as the percentage of participants with a confirmed best response of Complete response (CR) or Partial Response (PR) in participants with measurable disease at study entry. Modified RECIST Version 1.1 criteria is used to determine ORR (ie, CR or PR by IRR assessment and no progression in bone per PCWG3 by IRR assessment).

CR is disappearance of all target and non-target lesions; any pathological lymph nodes (whether target or non-target) must have reduction in short axis to <10 mm. PR is at least a 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum of diameters.

DOR is defined as the time from the first confirmed response (CR or PR by modified RECIST Version 1.1 in participants with nodal or visceral ± nodal disease) until the first date that Progressive Disease (PD) (using the same criteria) is documented.

DOR is defined as the time from the first confirmed response (CR or PR by modified RECIST Version 1.1 in participants with nodal or visceral ± nodal disease) until the first date that Progressive Disease (PD) (using the same criteria) is documented.

Confirmed PSA response is defined as ≥ 50% reduction in PSA from baseline on at least two assessments conducted at least 3 weeks apart. PSA response is calculated for all participants with PSA values at baseline and at least one post-baseline assessment. PSA is assessed by a local laboratory.

Confirmed PSA response is defined as ≥ 50% reduction in PSA from baseline on at least two assessments conducted at least 3 weeks apart. PSA response is calculated for all participants with PSA values at baseline and at least one post-baseline assessment. PSA is assessed by a local laboratory.

Defined as the percentage of participants with a complete response (CR), partial response (PR), and stable disease (SD) according to modified RECIST Version 1.1 with no progression in bone per PCWG3 criteria.

Defined as the percentage of participants with a Complete Response (CR), Partial Response (PR), and Stable Disease (SD), according to Modified RECIST Version 1.1 with no progression in bone per PCWG3 Criteria.

Time to PSA progression is defined as the time from randomization to the date that a ≥ 25% increase and absolute increase of ≥ 2 ng/mL above the nadir (or baseline value for participants who did not have a decline in PSA) in PSA was measured. The increase must be confirmed by a second consecutive assessment conducted at least 3 weeks later.

Time to PSA progression is defined as the time from randomization to the date that a ≥ 25% increase and absolute increase of ≥ 2 ng/mL above the nadir (or baseline value for participants who did not have a decline in PSA) in PSA was measured. The increase must be confirmed by a second consecutive assessment conducted at least 3 weeks later.

Changes in health and pain status from baseline to week 25 using: Functional Assessment of Cancer Therapy-Prostate questionnaire (FACT-P total score, on a scale of 0 to 156 where a higher score is better quality of life). The greater the decrease in score (ie more negative) from baseline to week 25 the greater the decrease in health status. Assessments completed during screening, at study treatment visits (Day 1, Day 15, Day 29, Day 43, Day 57, and every 29 days thereafter) (during the Treatment Phase, the Treatment Discontinuation Visit, and during the Follow-up Phase.

Changes in health and pain status from baseline to week 25 using: Brief Pain Inventory-Short Form (BPI-SF) questionnaire (on a scale of 1 to 10, from mild to severe, for pain and pain-interference scores). A decrease indicates less severe pain/interference. Assessments completed during screening, at study treatment visits (Day 1, Day 15, Day 29, Day 43, Day 57, and every 29 days thereafter) (during the Treatment Phase, the Treatment Discontinuation Visit, and during the Follow-up Phase.

Changes in health and pain status from baseline to week 25 using: EuroQol-5D-5L Visual Analogue Scale (EQ-5D-5L VAS; on a scale from 100 to 0, from best to worst health status). The greater the increase in score (including more negative) from baseline to week 25 the greater the increase in health status. Assessments completed during screening, at study treatment visits (Day 1, Day 15, Day 29, Day 43, Day 57, and every 29 days thereafter) during the Treatment Phase, the Treatment Discontinuation Visit, and during the Follow-up Phase.

Mean trough PK plasma concentration over time in the safety population with at least one PK sample collected at timepoints week 5, 9, 13 and 17; only Week 5 data presented.