Trial results for a Phase 2 study evaluating nivolumab in biochemically recurrent dMMR prostate cancer were posted on ClinicalTrials.gov on 2026-05-15. The study reported a median PSA progression-free survival of 6.7 months for participants treated with nivolumab.
Background
Nivolumab is an immune checkpoint inhibitor. The trial investigated its use in biochemically recurrent prostate cancer with deficient mismatch repair (dMMR). MMR deficiency is observed in 1-3% of unselected prostate cancer cases, and such cancers may show sensitivity to PD-1 blockade.
Trial design
The Phase 2 study (NCT04019964) enrolled 8 participants with prostate cancer and recurrent prostate cancer. The trial evaluated nivolumab as a monotherapy in this patient population.
Key results
The trial reported the following key measurements for nivolumab in biochemically recurrent prostate cancer:
- 2 participants achieved a PSA50 response.
- Median PSA progression-free survival (PSA-PFS) was 6.7 months.
- 2 participants achieved undetectable PSA levels.
- 3 participants experienced treatment-emergent adverse events, indicating the safety and tolerability profile.
What this means
The results from this Phase 2 study suggest that nivolumab may have activity in biochemically recurrent dMMR prostate cancer, as evidenced by a median PSA progression-free survival of 6.7 months. The observation that 2 participants achieved a PSA50 response and 2 participants achieved undetectable PSA levels indicates a potential for meaningful clinical benefit in a subset of patients. The safety profile, with 3 participants experiencing adverse events, will need further evaluation in larger studies. These findings warrant further investigation into the role of immune checkpoint blockade in this specific prostate cancer population.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT04019964, titled "Nivolumab in Biochemically Recurrent dMMR Prostate Cancer", were posted on 2026-05-15 on clinicaltrials.gov.