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Treatment of Metastatic Castration-Resistant Prostate Cancer With Homologous Recombination Deficiency

Phase 2
Terminated
Conditions
Metastatic Castration-Resistant Prostate Cancer (mCRPC)
Homologous Recombination Deficiency (HRD)
Interventions
Registration Number
NCT03712930
Lead Sponsor
BeiGene
Brief Summary

This study is designed to evaluate the efficacy of pamiparib in participants with metastatic castration-resistant prostate cancer (mCRPC) positive for circulating tumor cells (CTC) with homologous recombination deficiency (CTC-HRD). All participants will receive pamiparib. The purpose of this study is to demonstrate that pamiparib will improve Objective Response Rate (ORR) and Prostate-Specific Antigen (PSA) response rate

Detailed Description

This is a global, Phase 2, open-label study of pamiparib in approximately 100 participants with metastatic castration-resistant prostate cancer (mCRPC) positive for circulating tumor cells (CTC) with homologous recombination deficiency (CTC-HRD). Participants in Cohort 1 will include 50 mCRPC participants with CTC-HRD-positive, measurable metastatic disease (soft tissue with/without bone lesions), and positive BRCA1/2 mutation or negative/unknown BRCA1/2 mutation. Cohort 2 will include 30 mCRPC CTC-HRD positive participants with bone metastasis only and positive or negative/unknown BRCA1/2. Cohort 3 and 4 will include 20 mCRPC CTC-HRD negative/unknown participants with BRCA1/2 positive mutations, metastatic disease (measurable soft tissue with/without bone), and bone only. Participants will undergo PSA level assessments approximately every 4 weeks as well as tumor assessments every 8 weeks for 24 weeks and the every 12 weeks, or as clinically indicated. Administration of pamiparib will continue until disease progression, unacceptable toxicity, death or another discontinuation criterion is met.

Recruitment & Eligibility

Status
TERMINATED
Sex
Male
Target Recruitment
13
Inclusion Criteria
  • Men (≥ 18 years of age) with histologically or cytologically confirmed adenocarcinoma or poorly differentiated adenocarcinoma of the prostate without neuroendocrine differentiation with HRD deficiency by CTC-HRD assay and/or deleterious germline or somatic mutation in BRCA1 or BRCA2; mCRPC measurable disease and/or bone disease. • PSA progression with ≥ 3 rising PSA levels with ≥ 1 week between determinations and a screening PSA ≥ 2 μg/L (2 ng/mL).
  • Must be surgically or medically castrated with serum testosterone levels of ≤1.73 nmol/L (50 ng/dL), must have received ≥ 1 prior androgen receptor-targeted therapy, and must have received ≥ 1 taxane-based therapy.
  • mCRPC with 1 or 2 of the following:
  • Measurable disease per RECIST v1.1
  • Bone disease
  • CTC-HRD+ or BRCA1/2 mutation
  • PSA progression (PCWG3 criteria)
  • ≥1 androgen receptor-targeted therapy (eg, abiraterone acetate/prednisone or enzalutamide) for mCRPC with progressive disease
  • ≥1 taxane for metastatic prostate cancer

Key

Exclusion Criteria
  • Chemotherapy, hormonal therapy, biologic therapy, radionuclide therapy, immunotherapy, investigational agent, anticancer Chinese medicine, or herbal remedies ≤ 5 half-lives if the half-life is known, ≤ 14 days if not known, before start of study treatment
  • Continued treatment with a bisphosphonate or denosumab is allowed, if administered at a stable dose > 28 days before start of study treatment
  • Radiotherapy ≤ 21 days (≤ 14 days, if single fraction of radiotherapy) before start of study treatment

Prior treatment for prostate cancer with any of the following:

  • poly ADP ribose polymerase (PARP) inhibitor
  • Platinum
  • Cyclophosphamide
  • Mitoxantrone

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
PamiparibPamiparibParticipants will receive pamiparib for a period up to 1 year
Primary Outcome Measures
NameTimeMethod
Objective Response Rate (ORR) Determined by Independent Review CommitteeUp to 1 year and 6 months

ORR is the percentage of participants with a best objective response of complete response (CR) or partial response (PR) confirmed at a subsequent timepoint ≥ 4 weeks later by an Independent Review Committee (IRC).

Prostate-Specific Antigen (PSA) Response RateUp to 1 year and 6 months

PSA response rate is defined as the percentage of participants with PSA decline ≥ 50% from baseline \[confirmed by a second PSA value ≥ 3 weeks later\] for CTC-HRD-positive participants with or without measurable disease.

Secondary Outcome Measures
NameTimeMethod
Time to PSA ResponseUp to 1 year and 6 months

Time to PSA response is defined as the time from the date of the first dose of study drug to the first PSA decline ≥ 50% that is subsequently confirmed. Assessments are summarized for participants who have achieved a confirmed PSA response.

Time to Objective Response by InvestigatorUp to 1 year and 6 months

Time to objective response is defined as the time from the date of the first dose of study drug to the first documented confirmed response of CR or PR assessed by the investigator and summarized for participants who have achieved a confirmed objective response.

Clinical Benefit Rate By InvestigatorUp to 1 year and 6 months

Clinical Benefit Rate is the percentage of participants who achieved confirmed CR, PR, or SD or NON-CR/NON-PD. The minimum interval for confirmed CR and PR is 4 weeks and the measurement of SD or NON-CR/NON-PD is 7 weeks after first dose date.

Overall Survival (OS)Up to 1 year and 7 months

Overall survival is defined as the time from the date of the first dose of study drug to death due to any cause.

Duration of Response (DOR) by IRCUp to 1 year and 7 months

DOR is defined as the time from the date of the earliest documented CR or PR (that is subsequently confirmed) to radiographic disease progression or death due to any cause, whichever occurs first.

Objective Response Rate by InvestigatorUp to 1 year and 6 months

ORR is the percentage of participants with a best objective response of complete response (CR) or partial response (PR) confirmed at a subsequent timepoint ≥ 4 weeks later by the investigator.

Time to PSA ProgressionUp to 1 year and 7 months

Time to PSA progression is defined as the time from the date of the first dose of study drug to a ≥ 25% increase in PSA with an absolute increase of ≥ 2 ng/mL above the nadir (or above the baseline for participants with no PSA decline) after 12 weeks, confirmed by a second value ≥ 3 weeks later. Death for the participants with no PSA progression is also considered as an event.

Duration of PSA ResponseUp to 1 year and 7 months

Duration of PSA response is defined as the time from the date of the earliest documented PSA response (that is subsequently confirmed) to PSA progression or death due to any cause, whichever occurs first. PSA progression is defined as a ≥ 25% increase in PSA with an absolute increase of ≥ 2 μg/L above the nadir (or above the baseline for participants with no PSA decline) after12 weeks, confirmed by a second value ≥ 3 weeks later. The nadir is defined as the lowest value at or after baseline.

Time to Symptomatic Skeletal EventUp to 1 year and 7 months

Time to symptomatic skeletal event (SSE) is defined as time from the date of the first dose of study drug to the first symptomatic fracture, radiation or surgery to bone, or spinal cord compression.

Radiographic Progression-Free Survival by IRCUp to 1 year and 7 months

Radiographic progression-free survival is defined as the time from the date of the first dose of study drug to radiographic disease progression by IRC or death due to any cause, whichever occurs first.

Number of Participants With Treatment-Emergent Adverse Events Graded According to National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) Version 4.03From the date of first Pamiparib dose until 30 days after the last dose or initiation of new anti-cancer therapy, whichever occurs first. (Up to 1 year and 7 months)

Trial Locations

Locations (9)

University of Washington

🇺🇸

Seattle, Washington, United States

Liverpool Hospital

🇦🇺

Liverpool, New South Wales, Australia

University Cancer and Blood Center

🇺🇸

Athens, Georgia, United States

Montefiore Einstein Cancer Center

🇺🇸

Bronx, New York, United States

Gosford Hospital

🇦🇺

Gosford, New South Wales, Australia

Calvary Mater Newcastle

🇦🇺

Waratah, New South Wales, Australia

Icon Cancer Care Foundation

🇦🇺

South Brisbane, Queensland, Australia

Pan American Oncology Trials, LLC

🇵🇷

Rio Piedras, Puerto Rico

L Hospitalet de Llobregat

🇪🇸

Barcelona, Spain

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