A Trial of Belzutifan (PT2977, MK-6482) Tablets In Patients With Advanced Solid Tumors (MK-6482-001)

Inclusion Criteria:

* Has a diagnosis of locally advanced or metastatic solid tumor
* Is of age ≥ 18 years
* Has a life expectancy of ≥ 6 months
* Has adequate organ function
* If a female patient, must not be pregnant or breastfeeding and not a woman of childbearing potential (WOCBP) OR a WOCBP who uses contraception or is abstinent from heterosexual intercourse during the study and for a minimum of 30 days after the last study drug administration, or if a male patient, must be abstinent from heterosexual intercourse OR agree to use contraception
* Able to swallow oral medications

Additional Inclusion Criteria for GBM cohort

* Must have histologically confirmed glioblastoma, IDH-wild type that is first recurrent following radiation therapy and temozolomide according to the Response Assessment in Neuro-Oncology (RANO) criteria
* Must have archival tumor tissue available from a previous surgery for glioblastoma
* Must have measurable (defined as at least 1 cm x 1 cm) contrast-enhancing lesion by MRI imaging within 21 days of starting treatment
* Must be able to undergo MRI of the brain with gadolinium. Patients must be maintained on a stable or decreasing dose of corticosteroid regimen (no increase for 5 days) prior to this baseline MRI
* Must have recovered from prior therapy to grade ≤1 severity (except for alopecia and lymphocytopenia) National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE)

Exclusion Criteria:

* Has a history of untreated brain metastasis or history of leptomeningeal disease or spinal cord compression
* Has failed to recover from the reversible effects of prior anticancer therapy (does not apply to GBM cohort)
* Has uncontrolled or poorly controlled hypertension
* Has malabsorption due to prior gastrointestinal (GI) surgery or GI disease
* Has had any major cardiovascular event within 6 months prior to study drug administration
* Has any other clinically significant cardiac, respiratory, or other medical or psychiatric condition that might interfere with participation in the trial or interfere with the interpretation of trial results
* Has had major surgery within 4 weeks before first study drug administration
* Has known HIV
* Has an active infection requiring systemic treatment
* Is participating in another therapeutic clinical trial

Additional Excusion Criteria for GBM cohort:

* Has received prior anti-VEGF therapy including bevacizumab (i.e. patients must be bevacizumab naïve)
* Is receiving enzyme-inducing anti-epileptic drugs (EIAED). Patients may be on non-enzyme inducing anti-epileptic drugs or not be taking any anti-epileptic drugs. Patients previously treated with EIAED may be enrolled if they have been off the EIAED for 10 days or more prior to the first dose of belzutifan