Extension Study for Participants in Studies That Include Belzutifan (MK-6482-043/LITESPARK-043)

Researchers are looking for new ways to treat advanced solid tumors and von Hippel-Lindau (VHL)-related tumors: * Advanced means the cancer has spread to other parts of the body (metastatic) or cannot be removed with surgery * Solid tumors are cancers mostly in body organs and tissues, not in the blood or other body liquids * VHL-related tumors are tumors caused by VHL disease. VHL disease is passed down from parents to children and people with VHL disease have a higher chance of getting certain types of cancer Researchers want to learn about the long-term effects of a trial medicine called belzutifan. Belzutifan, also called MK-6482, is designed to block a protein that helps tumors grow and survive. This is an extension trial, which means only people who were in certain other belzutifan trials (called parent trials) may be able to join. The goal of this trial is to learn how long people live after they start taking belzutifan.

NCT Number	NCT07405164
Lead Sponsor	Merck Sharp & Dohme LLC
Conditions	Von Hippel-Lindau Disease, Malignant Neoplasms
Enrollment	450 participants
Start Date	2026-03-23
Primary Completion	2034-01-14 (estimated)
Study Completion	2034-01-14 (estimated)
Updated on ClinicalTrials.gov	2026-08-10