Trial results for a non-therapeutic study investigating peripheral T cell determinants in melanoma were posted on ClinicalTrials.gov on 2026-04-06. The study, which enrolled 25 participants, identified 52 genes predictive of response to anti-PD-1 therapy.
Background
Melanoma, particularly advanced melanoma, presents significant treatment challenges. Immunotherapy, specifically anti-PD-1 therapy, has transformed the treatment landscape for many patients. However, not all patients respond, and understanding the mechanisms of response and resistance is crucial for optimizing treatment strategies. This study aimed to explore the role of systemic T cells and their trafficking into the tumor microenvironment (TME) as potential predictors of immunotherapy outcomes, using T cell receptor (TCR) as a barcode to define these cells.
Trial design
This completed study enrolled 25 participants with Melanoma and Advanced Melanoma. It was a non-therapeutic study designed to assess peripheral T cell determinants of response and resistance to immunotherapy. The central hypothesis explored was that systemic T cells trafficking into the tumor microenvironment (TME), defined by tumor/blood small conditional RNA (scRNA) using T cell receptor (TCR) as a barcode, could predict response to Programmed death-1 (PD-1) therapy.
Key results
The study reported several key measurements related to T cell characteristics and their association with immunotherapy response in participants with melanoma:
- The Number of Genes Predictive of Response at Baseline was found to be 52 genes.
- The Number of Genes Predictive of Response at 24 Weeks was also found to be 52 genes.
- The Number of T-cell Sub-populations identified was 12 t-cell sub-populations.
- The Proportion of Participants With a Change in Clonal Expansion of T Cells Associated With Response to Anti-PD-1 Therapy was .08 proportion of participants.
- The Proportion of Participants With a Change in Distribution of T Cells Associated With Response to Anti-PD-1 Therapy was .08 proportion of participants.
- The Number of Transcriptional Migration Events observed was 2 transcriptional migration events.
What this means
The findings from this non-therapeutic study provide insights into potential peripheral T cell determinants that may predict response and resistance to anti-PD-1 immunotherapy in melanoma patients. The identification of 52 genes predictive of response at both baseline and 24 weeks, along with specific T-cell sub-populations and changes in clonal expansion and distribution, suggests avenues for further research into biomarkers. These results contribute to a deeper understanding of the immunological mechanisms underlying immunotherapy efficacy and could inform future strategies for patient selection or treatment monitoring.
Source
The information for these trial results was sourced from ClinicalTrials.gov, a public database of clinical studies. The results for the study NCT05105100, titled "Peripheral T Cell Determinants of Response and Resistance to Pembrolizumab in Melanoma", were posted on 2026-04-06 on clinicaltrials.gov.