Trial results for the Phase 2 study NCT03695471 investigating pembrolizumab in patients with Stage IB-IV Mycosis Fungoides were posted on ClinicalTrials.gov on 2025-08-11. The study reported that 25% of participants achieved an overall cutaneous response, with a median overall survival of 10.6 months.
Background
Pembrolizumab is an immunotherapy, a monoclonal antibody designed to help the body's immune system attack cancer cells. It may interfere with the ability of tumor cells to grow and spread. This trial investigated its use in Mycosis Fungoides and Sezary Syndrome.
Trial design
The study NCT03695471 was a Phase 2 trial that enrolled 9 participants. The trial investigated pembrolizumab in patients with Stage IB-IV Mycosis Fungoides, including specific stages like Stage IB Mycosis Fungoides and Sezary Syndrome AJCC v8, Stage II Mycosis Fungoides and Sezary Syndrome AJCC v8, and Stage IIA Mycosis Fungoides and Sezary Syndrome AJCC v8, as well as Sezary Syndrome.
Key results
Key findings from the trial for the treatment with pembrolizumab include:
- The proportion of overall cutaneous responders (Cutaneous Complete Response [CR], Cutaneous 90 Response [CR90], or Cutaneous Partial Response [PR]) at their 9th or final cycle was 0.25 (25%) of participants.
- The median percentage change in mSWAT Score from baseline was -5.015%.
- The median progression-free survival was 8.9 months (95% Confidence Interval).
- The median duration of response was 7.6 months (95% Confidence Interval).
- The median time to response was 2.04 months (Inter-Quartile Range).
- The median overall survival time was 10.6 months (95% Confidence Interval).
- Incidence of adverse events was reported in 5 participants for one measurement and 4 participants for another measurement.
What this means
The results from this Phase 2 trial provide preliminary insights into the activity of pembrolizumab in patients with Stage IB-IV Mycosis Fungoides. A cutaneous response rate of 25% and a median overall survival of 10.6 months suggest potential clinical benefit in this difficult-to-treat population. The observed median reduction in mSWAT score also indicates an improvement in cutaneous manifestations. Given the small enrollment of 9 participants, these findings are exploratory and warrant further investigation in larger studies.
Source
The information for this article was sourced from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03695471, titled "Pembrolizumab in Treating Patients With Stage IB-IV Mycosis Fungoides," were posted on 2025-08-11 on clinicaltrials.gov.