Trial Outcomes & Findings for A Phase III Trial of Niraparib Versus Physician's Choice in HER2 Negative, Germline BRCA Mutation-positive Breast Cancer Patients (NCT NCT01905592)

Previously treated, human epidermal growth factor receptor 2 HER2 negative, germline Breast Cancer gene (gBRCA) mutation positive breast cancer participants were enrolled. The study was terminated due to futility.

Of the 216 participants enrolled, 1 participant was not randomized and 9 participants enrolled based on a local BRCA test results were later determined to be BRCA wild type by central testing. Therefore, only 206 of the 216 participants enrolled were included in the analysis, and were considered in centrally confirmed intent-to-treat (ITT) Population.

A Phase III Trial of Niraparib Versus Physician's Choice in HER2 Negative, Germline BRCA Mutation-positive Breast Cancer Patients

The primary objective of this study is to compare progression-free survival (PFS), as assessed by blinded central review, of participants with advanced/metastatic human epidermal growth factor receptor 2 (HER2)-negative gBRCA mutation breast cancer when treated with niraparib as compared to those treated with physician's choice single agent chemotherapy standards (eribulin, vinorelbine, gemcitabine or capecitabine). PFS is defined as the date of randomization to the date of disease progression or death due to any cause, whichever occurs earlier as per Response evaluation criteria in solid tumors (RECIST) version (v)1.1 as determined by central review assessment. Progressive Disease is defined as at least a 20 percent (%) increase in the sum of diameters of measured lesions taking as references the smallest sum of diameters recorded on study (including Baseline) and an absolute increase of \>= 5 millimeter (mm).

Overall Survival (OS) was defined as the time from randomization to the date of death of any causes.

Blood samples were collected to evaluate central BRCA mutation status of participants. Baseline was defined as the most recent non-missing measurement prior to or on the first administration of study drug. Number of participants with central BRCA mutation status as BRCA1 positive only, BRCA2 positive only, Rearrangement only, BRCA1 and BRCA2 positive, BRCA1 positive and rearrangement, and BRCA2 positive and rearrangement were reported.

An adverse event (AE) is any untoward medical occurrence that occurs in a participant or clinical investigation participant administered a pharmaceutical product, and which does not necessarily have to have a causal relationship with this treatment. An SAE is defined as any untoward medical occurrence or effect in a participant, whether or not considered related to the protocol treatment, at any dose that results in death, is life-threatening, requires inpatient hospitalization or prolongation of existing participant hospitalization, results in persistent or significant disability or incapacity, is a congenital anomaly or birth defect, is an medically important event or reaction as per medical and scientific judgment. Adverse events which were not serious adverse events were considered as non serious adverse events.

PFS is defined as the date of randomization to the date of disease progression or death due to any cause, whichever occurs earlier as per RECIST version 1.1 as determined by Investigator assessment. Progressive Disease is defined as at least a 20 % increase in the sum of diameters of measured lesions taking as references the smallest sum of diameters recorded on study (including Baseline) and an absolute increase of \>= 5 mm.

Time to treatment failure was defined from the date of randomization to progression or discontinuation of treatment for any reason, including but not restricted to disease progression, treatment toxicity and death.

ORR was defined as the percentage of the participants who achieved a complete response (CR) or partial response (PR) to treatment evaluated using Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Complete Response (CR)=disappearance of all target and non-target lesions and normalization of tumor markers. Pathological lymph nodes must have short axis measures \<10 mm. Partial Response (PR)= at least a 30% decrease in the sum of measures (longest diameter for tumor lesions and short axis measure for nodes) of target lesions, taking as reference the Baseline sum of diameters. Percentage values are rounded off up to 1 decimal.

Duration of response was defined as the time from first documentation of response (confirmed CR or PR) until the time of first documentation of disease progression by RECIST v1.1 or death by any cause.

The number of participants with serious adverse events related to new malignancy were reported.

The number of participants with subsequent anticancer therapies were evaluated. Data has been reported as per following categories: any new anitumoral therapy, any chemotherapy, any radiotherapy, any surgery, any hormonal therapy, any targeted agents, and any other treatment. Participants may have received more than one subsequent therapies.

The number of participants with MCID status in EORTC-QLQ-C30 was planned to be evaluated.The EORTC- QLQ-C30 includes 30-items with single and multi-item scales. These include five functional scales (physical functioning, role functioning cognitive functioning, emotional functioning and social functioning), three symptom scales (fatigue, pain and nausea/vomiting), a global health status (GHS)/ Quality-of-Life (QoL) scale, and six single items (constipation, diarrhea, insomnia, dyspnea, appetite loss and financial difficulties). Response options are 1 to 4. The average score can be transformed to 0 to 100, a high score for functional scales/ GHS/QoL represents better functioning ability or health-related quality-of-life (HRQoL), whereas a high score for symptom scales/ single items represents significant symptomatology.

The number of participants with EQ-5D-5L scores by visit were planned to be evaluated. EQ-5D-5L is self-assessment questionnaire, consisting of 5 items covering 5 dimensions (mobility,self care, usual activities, pain/discomfort and anxiety/depression). Each dimension is measured by 5-point Likert scale(no problems, slight problems, moderate problems, severe problems and extreme problems). Responses for 5 dimensions together formed a 5-figure description of health state (e.g.11111 indicates no problems in all 5 dimensions). Each of these 5 figure health states were to be converted to a single index score. Range for EQ-5D-5L index score is 0 (worst health) to 100 (best health), higher the score better the health status.

The number of participants with any subsequent therapies post-discontinuation of study treatment and association with potential survival related outcomes were planned to be evaluated.

Biomarkers include germline and tumor mutations including somatic BRCA1 and 2 mutations, reversion mutations, loss of heterozygosity as well as genome landscape and transcriptional or functional measures of homologous recombination (HR) deficiency were planned to be evaluated.

Participants with germline BRCA1 and BRCA2 mutation status in association with survival related outcomes were planned to be evaluated.