Platinum and Taxane Chemo in Met Castration Resistant Prostate Cancer Patients With Alterations in DNA Damage Response Genes (OPTION-DDR)

April 15, 2026 updated by: Canadian Cancer Trials Group

A Randomized Phase III Trial Investigating Platinum and Taxane Chemotherapy in Metastatic Castration Resistant Prostate Cancer Patients With Alterations in DNA Damage Response Genes

The usual approach for most patients who are not in a study is treatment with docetaxel.

This study is being done to answer the following question: Can the chance of prostate cancer growing or spreading be lowered by adding a drug to the usual approach?

This study is being done to find out if this approach is better or worse than the usual approach for prostate cancer. The usual approach is defined as the care most people get for prostate cancer.

Study Overview

Detailed Description

If taking part in this study, the patient will either get docetaxel, or carboplatin in addition to docetaxel. In both cases, the cancer will be monitored by CT scans and bone scans every 9 weeks, and blood tests every 3 weeks. Study treatments, scans, and tests will continue until the disease gets worse.

After finishing study treatment, even if treatment is stopped before the disease gets worse, the study doctor will continue to follow patients condition, watch for side effects and keep track of the health of the patient. If treatment is stopped before the disease got worse, patients will be asked to continue getting CT scans and bone scans every 9 weeks, and blood tests every 3 weeks, until the disease worsens. If the disease gets worse while receiving treatment, or after treatment is stopped, the patient will be contacted by phone every 3 months for the rest of their life to monitor their status. Patients may be seen more often if the study doctor thinks it is necessary.

Study Type

Interventional

Enrollment (Estimated)

236

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

    • Alberta
      • Calgary, Alberta, Canada, T2N 5G2
        • Recruiting
        • Arthur J.E. Child Comprehensive Cancer Centre
        • Contact:
          • Steven M Yip
          • Phone Number: 604 877-6000
      • Edmonton, Alberta, Canada, T6G 1Z2
        • Recruiting
        • Cross Cancer Institute
        • Contact:
          • Michael Kolinsky
          • Phone Number: 780 432-8762
    • British Columbia
      • Vancouver, British Columbia, Canada, V5Z 4E6
        • Recruiting
        • BCCA - Vancouver
        • Contact:
          • Corinne Maurice Dror
          • Phone Number: 4634 604 877-6000
    • Ontario
      • Brampton, Ontario, Canada, L6R 3J7
        • Recruiting
        • William Osler Health System
        • Contact:
          • Marco Iafolla
      • Kitchener, Ontario, Canada, N2G 1G3
        • Recruiting
        • Waterloo Regional Health Network (WRHN)
        • Contact:
          • Anupam Batra
      • London, Ontario, Canada, N6A 5W9
        • Recruiting
        • London Health Sciences Centre Research Inc.
        • Contact:
          • Lilian Hanna
          • Phone Number: 519 685-8600
      • Ottawa, Ontario, Canada, K1H 8L6
        • Recruiting
        • Ottawa Hospital Research Institute
        • Contact:
          • Michael Ong
          • Phone Number: 75051 613 737-7700
      • Toronto, Ontario, Canada, M5G 2M9
        • Recruiting
        • University Health Network
        • Contact:
          • Di (Maria) Jiang
          • Phone Number: 647 993-0448
      • Toronto, Ontario, Canada, M4N 3M5
        • Recruiting
        • Odette Cancer Centre
        • Contact:
          • Daniel Khalaf
          • Phone Number: 416 480-4617
    • Quebec
      • Montreal, Quebec, Canada, H3T 1E2
        • Recruiting
        • The Jewish General Hospital
        • Contact:
          • April Rose
      • Montreal, Quebec, Canada, H2X 3E4
        • Recruiting
        • CHUM-Centre Hospitalier de l'Universite de Montreal
        • Contact:
          • Zineb Hamilou
          • Phone Number: 20688 514 890-8000
      • Québec, Quebec, Canada, G1J 1Z4
        • Recruiting
        • CHU de Quebec-Hopital l'Enfant-Jesus (HEJ)
        • Contact:
          • Eric Levesque
          • Phone Number: 418 525-4444
    • Saskatchewan
      • Regina, Saskatchewan, Canada, S4T 7T1
        • Recruiting
        • Allan Blair Cancer Centre
        • Contact:
          • Osama Souied
          • Phone Number: 306 766-2691
      • Saskatoon, Saskatchewan, Canada, S7N 4H4
        • Recruiting
        • Saskatoon Cancer Centre
        • Contact:
          • Nayyer Iqbal
          • Phone Number: 306 655-2710

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Histologic diagnosis of adenocarcinoma of the prostate. The presence of neuroendocrine or small cell carcinoma will be exclusionary
  • Prior treatment with any ARPI, such as abiraterone, enzalutamide, apalutamide, or darotlutamide, is required.
  • Participants must have recovered to ≤ grade 1 from all reversible toxicity related to prior systemic or radiation therapy, with the exception of chemotherapy induced alopecia and grade 2 peripheral neuropathy, and have adequate washout as follows:
  • Longest of one of the following:

    • Two weeks for oral therapies (such as abiraterone, apalutamide, enzalutamide, darolutamide and olaparib)
    • Standard cycle of standard IV or IM therapies (such as radium 223 or Lu-177-PSMA-617
    • 2 weeks, 5 half lives, or standard cycle length (whichever is longer) for investigational agents
  • Previous major surgery is permitted provided that surgery occurred at least 28 days prior to participant enrollment and that wound healing has occurred
  • Prior external beam radiation is permitted provided a minimum of 7 days have elapsed between the last dose of radiation and date of enrollment
  • Radiologically documented presence of metastatic disease within 28 days prior to randomization
  • Disease progression after ARPI therapy as assessed by the investigator with at least one of the following:
  • PSA progression with a minimum of two rising PSA values at least 1 week apart, at least 25% and 2ug/L above baseline/nadir.
  • Radiographic progression of soft tissue disease by RECIST 1.1 criteria or bone metastases by PCWG3 criteria.
  • Medical or surgical castration with serum testosterone levels <50ng/dL or <1.7mmol/L
  • Qualifying Tier I or Tier II (clinically significant/likely clinically significant or pathogenic / likely pathogenic) germline or somatic alterations involving one or more of the following DDR genes: BRCA1, BRCA2, ATM, ATR, BRIP1, BARD1, CDK12, CHEK1, CHEK2, ERCC2, FANCA, FANCC, FANCD2, FANCL, PALB2, RAD51B, RAD51C, RAD51D, RAD54L. Monoallelic gene deletions in isolation will not be eligible.
  • Age 18 years or older.
  • Eastern Cooperative Oncology Group (ECOG) Performance Status of ≤ 2
  • Participants must have adequate organ and marrow function measured within 14 days prior to enrolment
  • Life expectancy > 12 weeks.
  • If the participant and the participant's partner are of childbearing potential, they must agree to use medically accepted methods of contraception (e.g., barrier methods, including male condom, female condom, or diaphragm with spermicidal gel) during the course of the study and for 6 months after the last dose of study drug.
  • Participant is able (i.e. sufficiently fluent) and willing to complete the quality of life and health utility questionnaires in either English or French
  • Participant consent must be appropriately obtained in accordance with applicable local and regulatory requirements. Each participant must sign a consent form prior to enrollment in the trial to document their willingness to participate.
  • Participants must be accessible for treatment and follow-up. Investigators must assure themselves the participants enrolled on this trial will be available for complete documentation of the treatment, adverse events, and follow-up.
  • In accordance with CCTG policy, protocol treatment is to begin within 2 working days after participant enrolment.

Exclusion Criteria:

  • Received prior platinum chemotherapy (i.e. carboplatin, cisplatin, oxaliplatin, satraplatin) or prior taxane chemotherapy (docetaxel, paclitaxel, cabazitaxel) at any time for the treatment of prostate cancer with the exception of docetaxel for mCSPCor adjuvant therapy after curative intent treatment for localized prostate cancer, as long as it was no more than 6 cycles and at least 12 months have elapsed from their last treatment to the date of enrollment. If the participant received prior platinum or taxane chemotherapy for other cancers, then please contact the CCTG office to discuss this further with the trial team.
  • Active anticancer systemic therapy or investigational agents within 14 days of randomization.
  • Uncontrolled intercurrent illness including, but not limited to: active infection, symptomatic congestive heart failure (NYHA Class III or IV heart disease), unstable angina pectoris, cardiac arrhythmia, uncontrolled hypertension or psychiatric illness/social situations that would limit compliance with study requirements.
  • Participants with myelodysplastic syndrome/acute myeloid leukemia.
  • Malignancy within the previous 2-years with a > 30% probability of recurrence within 12 months, with the exception of non-melanoma skin cancer, and in-situ or superficial bladder cancer.
  • Participants with known symptomatic brain metastasis. However, participants with asymptomatic, treated brain metastases that have been stable for at least 12 weeks are eligible for study entry.
  • Participants with symptomatic or impending cord compression unless appropriately treated beforehand and clinically stable and asymptomatic.
  • Presence of a condition or situation, which, in the investigator's opinion, may put the participant at significant risk, may confound the study results, or may interfere significantly with participation in the study.
  • Live attenuated vaccination administered within 30 days prior to randomization.
  • For patients with known immunodeficiency virus (HIV) infection, the HIV viral load must be undetectable on effective anti-retroviral therapy within 6 months of enrollment.
  • For participants with evidence of chronic hepatitis B virus (HBV) infection, the HBV viral load must be undetectable on suppressive therapy, if indicated. Participants with a history of hepatitis C virus (HCV) infection must have been treated and cured. For participants with HCV infection who are currently on treatment, they are eligible if they have an undetectable HCV viral load.
  • Unable to obtain provincial reimbursement of carboplatin and docetaxel

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Docetaxel
75mg/m2 q21 days
Experimental: Carboplatin + Docetaxel
75mg/m2 q21 days
AUC5 q21 days

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Overall Survival
Time Frame: 5.25 years
5.25 years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
To compare the two treatment arms with respect to PSA response
Time Frame: 5.25 years
Defined as a reduction in PSA from baseline by 50%
5.25 years
To compare the two treatment arms with respect to progression free survival
Time Frame: 5.25 years
as defined by PCWG3 and RECIST 1.1
5.25 years
To compare the two treatment arms with respect to time to next systemic therapy
Time Frame: 5.25 years
5.25 years
To compare the two treatment arms with respect to time to number and severity of adverse events
Time Frame: 5.25 years
Utilizing CTCAE version 5.0
5.25 years
To compare the two treatment arms with respect to patient-reported Quality of Life (QoL) quantified by FACT-P questionnaire
Time Frame: 5.25 years
5.25 years
To compare the two treatment arms with respect to patient-reported Quality of Life (QoL) quantified by FACT-Taxane questionnaire
Time Frame: 5.25 years
5.25 years
To compare the two treatment arms with respect to patient-reported Quality of Life (QoL) quantified by BPI-SF questionnaire
Time Frame: 5.25 years
5.25 years
Economic Evaluation of healthcare utilization
Time Frame: 5.25 years
Health system resources will be identified as, but not limited to, clinic visits, treatments (radiation, surgery, medication), physician encounters, hospitalizations related to treatment and complications, emergent visits and diagnostics.
5.25 years
Economic Evaluation of health utilities measured by Eq-5D-5L
Time Frame: 5.25 years
5.25 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Study Chair: Michael Kolinsky, Cross Cancer Institute, Edmonton, Alberta, Canada

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 30, 2024

Primary Completion (Estimated)

September 30, 2029

Study Completion (Estimated)

March 31, 2030

Study Registration Dates

First Submitted

May 27, 2024

First Submitted That Met QC Criteria

May 27, 2024

First Posted (Actual)

June 3, 2024

Study Record Updates

Last Update Posted (Actual)

April 16, 2026

Last Update Submitted That Met QC Criteria

April 15, 2026

Last Verified

April 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

As per CCTG policy

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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