Understanding T Cell Responses to Pembrolizumab in Melanoma

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

University of California, San Francisco · NCT05105100

This study is trying to see how different types of T cells in patients with advanced melanoma affect their response to the drug pembrolizumab and how well they do over time.

Quick facts

Study typeObservational
Enrollment25 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity of California, San Francisco (other)
Drugs / interventionspembrolizumab, prednisone, immunotherapy
Locations1 site (San Francisco, California)
Trial IDNCT05105100 on ClinicalTrials.gov

What this trial studies

This observational study investigates how peripheral T cell profiles influence the response and resistance to pembrolizumab in patients with advanced melanoma. It aims to correlate changes in T cell activation and expansion within the tumor microenvironment with treatment outcomes such as overall survival and progression-free survival. Patients will be monitored for six months after starting pembrolizumab, with the potential for long-term follow-up on survival status. The study utilizes advanced techniques like small conditional RNA and T cell receptor barcoding to analyze T cell characteristics.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with histologically confirmed locally advanced or metastatic melanoma who are starting pembrolizumab monotherapy.

Not a fit: Patients who are not starting pembrolizumab or those with non-melanoma cancers will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved predictions of treatment responses to pembrolizumab, enhancing personalized therapy for melanoma patients.

How similar studies have performed: Other studies have shown promising results in correlating immune profiles with treatment responses in melanoma, suggesting this approach has potential.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Patients must have histologically confirmed locally advanced or metastatic melanoma and be starting on standard of care pembrolizumab monotherapy. Patients may have received any or no prior anti-cancer therapy without limitation.
2. Must have one or more sites of disease amenable to biopsy (tumor, skin, lymph node, pleural fluid, peritoneal fluid, cerebral spinal fluid (CSF)).
3. 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.
4. Participants must be age 18 years or older on the day of signing informed consent.
5. Have the ability to provide written informed consent for the trial.
6. Be able and willing to comply with study procedures including provision of basic demographic information and medical history.
7. Be willing to receive periodic follow up phone calls to monitor health status and survival status.

Exclusion Criteria:

1. 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)).
2. Has received prior systemic anti-cancer therapy including investigational agents within the prior 2 weeks.
3. 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.
4. Has a contraindication to tissue biopsy for minimally-invasive research-procedure
5. Contraindication to phlebotomy (up to 20 milliliters (mL)) per phlebotomy every three weeks).

Where this trial is running

San Francisco, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Melanoma, Advanced Melanoma, Peripheral T Cell, Pembrolizumab

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.