Trial results for an early phase 1 study investigating pembrolizumab and imiquimod in patients with Stage IIIB-IV melanoma were posted on 2026-03-19. The study reported a mean duration of response of 8.1 months among participants. This pilot trial aimed to evaluate the side effects and efficacy of the combination therapy.
Background
Pembrolizumab (Keytruda) is an immunotherapy drug designed to block the PD-1 pathway, thereby enhancing the immune system's ability to target cancer cells. Imiquimod is an immune response modifier that can stimulate the immune system. This trial investigated the potential benefits of combining these two agents in the treatment of advanced melanoma.
Trial design
The completed early phase 1 trial (NCT03276832) enrolled 7 participants with Stage IIIB-IV melanoma, specifically including metastatic, Stage IIIB, Stage IIIC, and Stage IV cutaneous melanoma. The study evaluated the combination of imiquimod and pembrolizumab. The primary objectives of this pilot study were to investigate the side effects and how well the combined treatment works in this patient population.
Key results
Key measurements from the trial included:
- The mean duration of response for the combination treatment was 8.1 months.
- Incidence of Adverse Events (AEs) was reported in 2, 3, 2, 1, 3, 5, and 1 participants across different event categories.
- 6 participants achieved overall survival.
- 4 participants achieved progression-free survival.
- Tumor response was observed in 3 participants and 1 participant, as separate measurements.
What this means
As an early phase 1 pilot study with a small enrollment of 7 participants, these results provide initial insights into the safety and potential activity of combining pembrolizumab and imiquimod for advanced melanoma. The reported mean duration of response of 8.1 months suggests potential clinical benefit, warranting further investigation in larger trials. The various counts for adverse events, overall survival, progression-free survival, and tumor response contribute to understanding the preliminary profile of this combination therapy.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03276832, titled "Imiquimod and Pembrolizumab in Treating Patients With Stage IIIB-IV Melanoma," were posted on 2026-03-19 on clinicaltrials.gov.