Trial Purpose

This is a two-part study of pembrolizumab (MK-3475) in paediatric participants who have any of the following types of cancer:

  • advanced melanoma (6 months to <18 years of age),
  • advanced, relapsed or refractory programmed death-ligand 1 (PD-L1)-positive malignant solid tumour or other lymphoma (6 months to <18 years of age),
  • relapsed or refractory classical Hodgkin lymphoma (rrcHL) (3 years to <18 years of age) or
  • advanced relapsed or refractory microsatellite-instability-high (MSI-H) solid tumours (6 months to <18 years of age) or
  • advanced relapsed or refractory tumour-mutational burden-high ≥10 mutation/Mb (TMB-H) solid tumours (6 months to <18 years of age)

Part 1 will find the maximum tolerated dose (MTD)/maximum administered dose (MAD), confirm the dose and find the recommended Phase 2 dose (RP2D) for pembrolizumab therapy. Part 2 will further evaluate the safety and efficacy at the paediatric RP2D.

The primary hypothesis of this study is that intravenous (IV) administration of pembrolizumab to children with either advanced melanoma; a PD-L1 positive advanced, relapsed or refractory solid tumour or other lymphoma; advanced, relapsed or refractory MSI-H solid tumour; or rrcHL, will result in an Objective Response Rate (ORR) greater than 10% for at least one of these types of cancer. The 10% assessment does not apply to the MSI-H and TMB-H cohorts.

With Amendment 8, enrolment of participants with solid tumours and participants aged 6 months to <12 years with melanoma were closed. Enrolment of participants aged ≥12 years to ≤18 years with melanoma continues. Enrolment of participants with MSI-H and TMB-H solid tumours also continues.

Learn More on



When speaking to your doctor, please have the trial identifier number available.

About The Study

Trial Phase Icon

Phase 1

Tests the medicine or vaccine in a small group of 20 to 100 volunteers who are usually healthy, but not always. The trial often takes place in a hospital.

Phase 2

Tests the medicine or vaccine in approximately 100 to 500 volunteers. In the case of medicines, volunteers usually have the disease or condition the investigational medicine is designed to treat. In vaccine studies, the volunteers are usually healthy.

Trial start Icon


  • Actual study start date 18 March 2015
  • Estimated primary completion date 6 May 2025
  • Estimated study completion date 6 May 2025


Only a qualified healthcare professional can determine your eligibility. However, this information may be useful in starting a conversation with your doctor.

Conditions Icon


Classical Hodgkin Lymphoma, Lymphoma, Melanoma, Microsatellite-instability-high Solid Tumor, Solid Tumor

Age Range Icon

Age Range

6 - 17

Sex Icon



Trial locations

Locations provided may not reflect the most current site information. Please call the number provided in the location results to confirm.