(UroToday.com) The 2026 ASCO annual meeting featured a prostate cancer trials in progress session and a presentation by Dr. Michael Ong discussing OPTION-DDR (CCTG-PR-25), a randomized phase III trial investigating platinum and taxane chemotherapy in metastatic castration resistant prostate cancer (mCRPC) patients with alterations in DDR genes. Patients with mCRPC have a poor prognosis. As part of their standard treatment, patients undergo genetic testing to determine if PARP inhibitors would be appropriate for their care. The OPTION-DDR trial leverages standard of care genetic testing to identify patients with alterations in DDR genes. The trial aims to determine if adding carboplatin to standard of care docetaxel in patients with mCRPC with genetic alterations in DDR genes improves overall survival.
Patients with mCRPC with a qualifying DDR gene alteration (BRCA1, BRCA2, ATM, ATR, BARD1, BRIP1, FANCI, ATRX2, CHEK1, CHEK2, ERCC2, FANCA, FANCC, FANCL, PALB2, RAD51B, RAD51C, RAD51D, RAD54L) and no prior platinum or taxane chemotherapy for mCRPC will be randomized 1:1 to Arm A (docetaxel 75 mg/m² (or 60 mg/m2)) versus Arm B (carboplatin AUC 6 (or 4) + docetaxel 75 mg/m² (or 60 mg/m2)). Patients will be stratified by (i) DDR alteration, (ii) prior PARP inhibition, and (iii) docetaxel use for mCSPC:
The primary endpoint is overall survival, and secondary endpoints include:
- PSA response
- Radiographic progression free survival (RECIST 1.1 and PCWG3)
- Time to next therapy
- Adverse events
- CTCAE v5.0
- Quality of life: FACT-P
- Health economics evaluation
The target accrual is 236 participants over 3.25 years with 2 years of follow-up to detect a hazard ratio of 0.65 in overall survival using a 5% (2-sided) level test with a power of 80%. Patients will be followed every 3 months until death. The trial was activated on October 8, 2024, and the first patient was enrolled on December 30, 2024. There are 14 sites open across Canada, with 17 patients accrued to date:
Presented by: Michael Ong, MD, FRCPC, The Ottawa Hospital Cancer Centre, Ottawa, Ontario, Canada
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Associate Professor of Urology, Georgia Cancer Center, Wellstar MCG Health, @zklaassen_md on Twitter during the American Society of Clinical Oncology Genitourinary (ASCO) Annual Meeting held in Chicago, IL between May 29th and June 1st, 2026