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Trials
A Study of Pembrolizumab in Japanese Pediatric Participants With Solid Tumors or Lymphomas and Japanese Adult Participants With Merkel Cell Carcinoma (MK-3475-G21/KEYNOTE-G21)

trialsTrialRecruiting

A Study of Pembrolizumab in Japanese Pediatric Participants With Solid Tumors or Lymphomas and Japanese Adult Participants With Merkel Cell Carcinoma (MK-3475-G21/KEYNOTE-G21)

A phase 1/2 trial of Pembrolizumab in merkel cell carcinoma and non-Hodgkin lymphoma, run by Merck Sharp & Dohme LLC, now recruiting.

Also called: KEYNOTE-G21

Overview Connected5

Overview

A Study of Pembrolizumab in Japanese Pediatric Participants With Solid Tumors or Lymphomas and Japanese Adult Participants With Merkel Cell Carcinoma (MK-3475-G21/KEYNOTE-G21) is a phase 1/2 interventional study registered as NCT07302347 by Merck Sharp & Dohme LLC, with 20 participants planned, started 2026-06-23 and due to reach its primary completion in 2029-03-30. Interventions recorded: Pembrolizumab.

Setting

A Phase I/II Study of Pembrolizumab (MK-3475) in Japanese Pediatric Participants With Specific Solid Tumors or Lymphomas, or in Japanese Adult Participants With Advanced Merkel Cell Carcinoma (KEYNOTE-G21)

Phase

Phase 1/2

Sponsor

Merck Sharp & Dohme LLC

Registry

Started

2026-06-23

Enrolled

20 enrolled

Connected

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cancers

Merkel cell carcinoma Non-Hodgkin lymphoma (all types)

technologies

Immune checkpoint inhibitors

drugs

ApprovedMonoclonal antibody (anti-PD-1)

Pembrolizumab · Keytruda / Keytruda Qlex (SC)

companies

Merck & Co. (MSD)

Evidence strength20/100 · Preliminary

How much and what kind of evidence, not how big the benefit. Click for the breakdown.

Phase 1/2+8
20 enrolled+7
No structured primary endpoint0
Result: recruiting0
No independent replication recorded0
A linked product is approved+5

Formula disclosed on the evidence page.

ProvenanceLast edited 2026-09-22 · Jude Gomila · Wave 2 corpus-only joins applied · diff · file

Sources & links

ClinicalTrials.gov NCT07302347

Data

JSON ·

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Cancers

Merkel cell carcinoma
Non-Hodgkin lymphoma (all types)

Technologies

Immune checkpoint inhibitors

Products

Pembrolizumab

Companies

Merck & Co. (MSD)

Not yet reviewedNeeds expert (clinical) review. Review this page or see the review queue and roster.

Model panel commentary is coming to this page: machine commentary, not clinical review.

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