Breaking News: Unlocking the Potential of Pembrolizumab in Melanoma Treatment
A ray of hope shines for melanoma patients, but is it too good to be true? The phase 2 PLUME trial has presented intriguing results, suggesting a potential breakthrough in the treatment of uveal melanoma. But here's where it gets controversial...
The combination of pembrolizumab (Keytruda) and lenvatinib (Lenvima) has shown promising progression-free survival (PFS) rates, especially in patients pretreated with tebentafusp (Kimtrak). Dr. Manuel Rodrigues, a medical oncologist at Institut Curie, presented these findings at the European Society for Medical Oncology (ESMO) Congress 2025.
In both patient cohorts, the study met its primary endpoint, with impressive PFS rates at 27 weeks. For patients who were HLA-A02:01-negative and treatment-naïve, the PFS rate was 31.8%. However, the real standout was the cohort of HLA-A02:01-positive patients pretreated with tebentafusp, who achieved a remarkable PFS rate of 60.7%.
"The activity of treatments post-tebentafusp seems enhanced compared to historical data," Dr. Rodrigues explained, referring to phase 3 studies of tebentafusp. He further added, "The combination of lenvatinib and pembrolizumab exhibited encouraging results, indicating a potential synergy between these treatments, especially in patients previously treated with tebentafusp."
Safety-wise, the overall profile was consistent with previous trials involving this combination. There were no treatment-related deaths, and the most common treatment-related adverse events included fatigue, hypertension, diarrhea, and hypothyroidism.
While these findings are undoubtedly promising, Dr. Rodrigues urged caution due to the small sample size and single-arm design of the study. He emphasized the ongoing biomarker analyses and real-world comparisons to refine patient selection further.
The PLUME study, an academic, monocentric, single-arm phase 2 trial conducted at Institut Curie in Paris, enrolled 51 patients who were immune checkpoint inhibitor-naïve. These patients were divided into two cohorts based on their HLA-A*02:01 status and pretreatment with tebentafusp.
The primary endpoint of the study was 27-week PFS, and the treatment regimen consisted of pembrolizumab intravenously every 3 weeks and lenvatinib orally daily until progression.
Uveal melanoma, a unique form of melanoma, has a median overall survival of about 20 months. Tebentafusp, a bispecific TCR-anti-CD3 fusion protein, has shown benefits in improving OS for metastatic uveal melanoma patients, but only for those who are HLA-A*02:01-positive, which is approximately 45% of patients. Checkpoint inhibitors like pembrolizumab have had limited efficacy due to low mutational burden and an immunosuppressive microenvironment.
The addition of lenvatinib, with its VEGFR/FGFR blockade, aims to normalize vasculature, reduce tumor-associated macrophages, and enhance T-cell infiltration. This combination has shown promise in endometrial and renal cancers, outperforming monotherapy.
Dr. Rodrigues disclosed personal and institutional financial interests with various pharmaceutical companies, including Immunocore, GSK, AstraZeneca, Abbvie, Johnson & Johnson, Merck, and Daiichi-Sankyo. Merck provided product samples for the PLUME trial.
These findings raise intriguing questions: Could this combination therapy be a game-changer for melanoma treatment? Or is it too early to celebrate? What are your thoughts on the potential of pembrolizumab and lenvatinib in melanoma populations? Share your insights and let's discuss!
