Efficacy and Safety Comparison of Niraparib to Placebo in Participants With Human Epidermal Growth Factor 2 Negative (HER2-) Breast Cancer Susceptibility Gene Mutation (BRCAmut) or Triple-Negative Breast Cancer (TNBC) With Molecular Disease

Official Title

A Randomized Phase 3 Double-Blinded Study Comparing the Efficacy and Safety of Niraparib to Placebo in Participants With Either HER2-Negative BRCA-Mutated or Triple-Negative Breast Cancer With Molecular Disease Based on Presence of Circulating Tumour DNA After Definitive Therapy (ZEST)


This study will assess the efficacy and safety of Niraparib in participants with either tumour mutation in the BRCA gene (tBRCAmut) HER2- breast cancer (Independent of hormone receptor [HR] status, including HR positive [+] and TNBC) or tumour BRCA wild type (tBRCAwt) TNBC with molecular disease based on the presence of circulating tumour Deoxyribonucleic acid (ctDNA) following surgery or completion of adjuvant therapy. Participants who have completed definitive therapy at any time in the past are eligible for ctDNA monitoring and potential enrollment onto the trial.

Trial Description

Primary Outcome:

  • Disease-free survival (DFS)
Secondary Outcome:
  • Overall survival (OS)
  • Time to progression on next anticancer therapy (TTP)
  • Distant recurrence-free survival (DRFS)
  • Number of participants with Treatment-emergent adverse events (TEAEs), Serious adverse events (SAEs), adverse events of special interest (AESIs), TEAEs leading to death, TEAEs leading to dose modifications and discontinuation
  • Number of participants with clinically significant changes in laboratory parameters, vital signs, Eastern Cooperative Oncology Group (ECOG) status, and use of concomitant medications
  • Change from Baseline in European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (EORTC QLQ-C30) (Scores on a scale)
  • Change from Baseline in the Functional Assessment of Cancer Therapy - General Population(FACT-GP5) (Scores on a scale)
  • Patient reported Outcomes Version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) (Scores on a scale)

View this trial on ClinicalTrials.gov

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Canadian Cancer Society

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