Trial Purpose

Substudy 02C is part of a larger research study that is testing experimental treatments for melanoma, a type of skin cancer. The larger study is the umbrella study.

The goal of substudy 02C is to evaluate the safety and efficacy of investigational treatment arms in participants with Stage III melanoma who are candidates for neoadjuvant therapy to identify the investigational agent(s) that, when used in combination, are superior to the current treatment options/historical control available.

Arm 1: Pembrolizumab + Vibostolimab, Arm 2: Pembrolizumab + Gebasaxturev, and Arm 3: Pembrolizumab were added in the base protocol on 13-Nov-2019, and enrollment into those arms has been completed. Arm 4: Pembrolizumab + MK-4830 was added in Amendment 04 on 20-Dec-2021, and enrollment into that arm has been completed. Arm 5: Favezelimab + Pembrolizumab and Arm 6: Pembrolizumab + all-trans retinoic acid (ATRA) were added in Amendment 06 on 25-Jun-2022, and enrollment is ongoing.

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Age Range

18 - 120



About the trial

Current trial phase

Trial Phase 1

Investigational medication is tested for safety on a relatively small group of 20 to 100 volunteers who are usually healthy, but not always. Phase 1 trials may happen in a doctor’s office or a hospital.

Trial Phase 2

In Phase 2 trials, researchers try to find out if a treatment works in about 100 to 500 participants – usually people who have the health condition the treatment is intended to treat. In vaccine trials, the participants are usually healthy. Phase 2 trials may happen in a doctor’s office, a clinic, or a hospital.

Trial start and end dates
  • Trial start date June 26, 2020
  • Estimated primary completion date April 3, 2030
  • Estimated trial completion date April 3, 2030

Trial locations

Locations shown may have changed in some cases. Please call the number listed in the location results to confirm the nearest trial site. Talk with a trial site member for more information.

What can you do next?

If you think this clinical trial might be a good fit and you are interested in taking part, take the next step to see if you are eligible.

Discuss with your doctor or care team

Print this page with details about the trial or email it to your doctor to discuss the clinical trial during your next visit.

Get help talking with your doctor or care team

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When you talk with your doctor or clinical trial team member, please have the trial identifier number available.

Taking part in a clinical trial is an important decision

If you are considering joining a clinical trial, first learn as much as you can about:

  • The investigational treatment that is being studied
  • What the risks and possible benefits are for participants

Talk to your doctor about the clinical trial before you decide to join.

Read our “What to Consider” page for more questions to ask and think about