Trial results for a Phase 2 study evaluating pembrolizumab (Keytruda) as maintenance therapy for platinum-resistant ovarian, fallopian tube, or peritoneal cancer were posted on ClinicalTrials.gov on 2026-05-20. The study reported a progression-free survival rate of 5.0% at 6 months from the start of maintenance pembrolizumab treatment.
Background
This study investigated pembrolizumab (Keytruda) as a maintenance therapy following weekly paclitaxel for participants with platinum-resistant ovarian, fallopian tube, or peritoneal cancer. The aim was to explore the potential for extending progression-free survival in this challenging patient population.
Trial design
The Phase 2 study (NCT03430700) enrolled 20 participants with platinum-resistant ovarian, fallopian tube, or peritoneal cancer. The overall aim was to demonstrate a clinically meaningful extension of progression-free survival using maintenance pembrolizumab following pre-trial weekly paclitaxel. The study also aimed to investigate the immune microenvironment before and during pembrolizumab therapy.
Key results
The trial reported the following key measurements for the treatment group:
- The Progression-Free Survival Rate at 6 Months from the start of maintenance pembrolizumab was 5.0%.
- Progression Free Survival at 6 Months measured from the start of pre-trial weekly paclitaxel was 95.0%.
- Median Overall Survival was 10.5 months.
- The Disease Response rate was 5% of participants.
- Treatment compliance was observed in 1 participant.
What this means
The results of this Phase 2 study provide initial data on pembrolizumab as maintenance therapy for platinum-resistant ovarian, fallopian tube, or peritoneal cancer. A progression-free survival rate of 5.0% at 6 months from the start of maintenance pembrolizumab suggests limited efficacy in extending PFS directly from the maintenance phase. However, the 95.0% progression-free survival at 6 months measured from the start of pre-trial weekly paclitaxel indicates that a significant proportion of participants maintained disease control through the initial paclitaxel and into the maintenance phase. The median overall survival of 10.5 months offers a broader perspective on patient outcomes. The low disease response rate of 5% and the reported treatment compliance for only 1 participant warrant further investigation to understand the full clinical implications and patient population characteristics in this study.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT03430700, titled "Trial of Pembrolizumab Following Weekly Paclitaxel for Platinum-resistant Ovarian, Fallopian Tube or Peritoneal Cancer", were posted on 2026-05-20 on clinicaltrials.gov.