N/A N=25

Peripheral T Cell Determinants of Response and Resistance to Pembrolizumab in Melanoma

Melanoma · Advanced Melanoma

Bottom Line

View on ClinicalTrials.gov: NCT05105100 ↗

Enrolled (actual)

Serious AEs

4.0%

Results posted

Apr 2026

Primary outcome: Primary: Number of Genes Predictive of Response at Baseline — 52 genes

Study Design & Population

Study type: Observational
Phase: N/A
Interventions: Biopsy (Procedure); Biospecimen Collection (Procedure)
Age: Adult, Older Adult · 18+ yrs
Sex: All
Sponsor: University of California, San Francisco
Primary completion: Sep 2025

Outcome Measures

Outcome	Result	p-value
PRIMARY Number of Genes Predictive of Response at Baseline	52	—
PRIMARY Number of Genes Predictive of Response at 24 Weeks	52	—
PRIMARY Number of T-cell Sub-populations	12	—
PRIMARY Proportion of Participants With a Change in Clonal Expansion of T Cells Associated With Response to Anti-PD-1 Therapy	.08	—
PRIMARY Proportion of Participants With a Change in Distribution of T Cells Associated With Response to Anti-PD-1 Therapy	.08	—
PRIMARY Number of Transcriptional Migration Events	2	—

Summary

This is a non-therapeutic study assessing peripheral T cell determinants of response and resistance to immunotherapy in patients with advanced melanoma.The hypothesis is that systemic T cells traffic into the tumor microenvironment (TME) can predict response and resistance to immunotherapy. These systemic tumor directed T cells can be defined by tumor/blood small conditional RNA (scRNA) using T cell receptor (TCR) as a barcode and can help predict response to Programmed death-1 (PD-1) therapy.

Eligibility Criteria

Inclusion Criteria

Participants must have histologically confirmed locally advanced or metastatic melanoma and be starting on standard of care pembrolizumab monotherapy. Participants may have received any or no prior anti-cancer therapy without limitation.
Must have one or more sites of disease amenable to biopsy (tumor, skin, lymph node, pleural fluid, peritoneal fluid, cerebral spinal fluid (CSF)).
Have measurable disease based on Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. Lesions situated in a previously irradiated area are considered measurable if progression has been demonstrated in such lesions.
Participants must be age 18 years or older on the day of signing informed consent.
Have the ability to provide written informed consent for the trial.
Be able and willing to comply with study procedures including provision of basic demographic information and medical history.
Be willing to receive periodic follow up phone calls to monitor health status and survival status.

Exclusion Criteria

Has received prior therapy with an anti-PD-1, anti-PD-L1, or anti PD L2 agent or with an agent directed to another stimulatory or co-inhibitory T-cell receptor (e.g., cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), OX 40, Cluster of Differentiation 137 (CD137)).
Has received prior systemic anti-cancer therapy including investigational agents within the prior 2 weeks.
Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of immunosuppressive therapy within 7 days prior to the first dose of study drug.
Has a contraindication to tissue biopsy for minimally invasive research-procedure.
Contraindication to phlebotomy (up to 40 milliliters (mL)) per phlebotomy every three weeks).

View full record on ClinicalTrials.gov →

Data sourced from ClinicalTrials.gov (NCT05105100). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.