Trial results for the study investigating pembrolizumab in combination with rintatolimod and cisplatin for recurrent ovarian cancer were posted on ClinicalTrials.gov on 2025-07-20. The combination therapy achieved an Objective Response Rate (ORR) of 50% and reported 0 dose-limiting toxicities (DLTs) in patients with recurrent platinum-sensitive ovarian cancer.
Background
This study evaluated the effectiveness of combining intensive locoregional intraperitoneal (IP) chemoimmunotherapy of cisplatin with IP rintatolimod (TLR-3 agonist) and intravenous infusion of the checkpoint inhibitor pembrolizumab for patients with recurrent platinum-sensitive ovarian cancer. Pembrolizumab is an immune checkpoint inhibitor, and this trial explored its use in a combination regimen.
Trial design
The study (NCT03734692) was a Phase 1/Phase 2 single-arm trial that enrolled 24 participants. It investigated the combination of intraperitoneal cisplatin, intraperitoneal rintatolimod, and intravenous pembrolizumab for patients with recurrent platinum-sensitive ovarian cancer. The trial evaluated the effectiveness and safety of this chemo-immunotherapy regimen.
Key results
Results from the trial demonstrated an Objective Response Rate (ORR) of 50 percentage of patients for the combination of cisplatin, rintatolimod, and pembrolizumab in patients with recurrent ovarian cancer. Importantly, 0 patients experienced dose-limiting toxicities (DLTs) related to the treatment.
Further measurements related to immune cell changes included:
- Change in CD45 Cells (mean percentages with standard deviations): 6.8 (SD: 44.6), 21.5 (SD: 13.8), and 28.4 (SD: 19.3).
- Percent of CD45 Cells (mean percentages with standard deviations): 57.9 (SD: 28.9), 76 (SD: 32), 91.3 (SD: 6.5), and 90.5 (SD: 8.5).
- Change in CD3 Cells (mean percentages with standard deviations): -14.4 (SD: 13.8), 22.5 (SD: 15.6), and -7.8 (SD: 19.8).
What this means
The observed 50% Objective Response Rate in recurrent ovarian cancer patients treated with the combination of pembrolizumab, rintatolimod, and cisplatin suggests potential efficacy for this regimen. The finding of 0 dose-limiting toxicities indicates a favorable safety profile within the study population. These results support further investigation into this multi-modal chemo-immunotherapy approach for platinum-sensitive recurrent ovarian cancer.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03734692, titled "Systemic Immune Checkpoint Blockade and Intraperitoneal Chemo-Immunotherapy in Recurrent Ovarian Cancer," were posted on 2025-07-20 on clinicaltrials.gov.