NCT07049926 · Merck Sharp & Dohme LLC
Substudy 03C: A Study of Combination Therapies in Participants With Renal Cell Carcinoma With Recurrent Disease During or After Anti-PD-(L)1 Therapy (MK-3475-03C/KEYMAKER-U03)
What this study is about
Substudy 03C is part of a larger research study that is testing experimental treatments for renal cell carcinoma (RCC). The larger study is the umbrella study (U03).
View original scientific description
Substudy 03C is part of a larger research study that is testing experimental treatments for renal cell carcinoma (RCC). The larger study is the umbrella study (U03). The goal of substudy 03C is to evaluate the safety and efficacy of experimental combinations of investigational agents in participants with clear cell renal cell carcinoma (ccRCC) who have recurrent disease during or after anti-programmed cell death 1/programmed cell death ligand 1 (PD-\[L\]1) adjuvant therapy.
Interventions
DRUG
Belzutifan
Oral Tablet
DRUG
Zanzalintinib
Oral Tablet
Primary outcome measures
Safety Lead In Phase: Number of participants who experience one or more dose-limiting toxicities (DLTs)
Time frame: Up to approximately 21 days
DLTs are defined as any of a pre-specified list of toxicities if assessed by the investigator to be possibly, probably, or definitely related to study treatment administration, excluding toxicities clearly not related to the drug, such as disease progression, environmental factors, unrelated trauma, etc.
Safety Lead In Phase: Number of participants who experience one or more adverse events (AEs)
Time frame: Up to approximately 74 months
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.
Safety Lead In Phase: Number of participants who discontinue study treatment due to an AE
Time frame: Up to approximately 74 months
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.
Efficacy Phase: Number of participants who experience one or more DLTs
Time frame: Up to approximately 21 days
DLTs are defined as any of a pre-specified list of toxicities if assessed by the investigator to be possibly, probably, or definitely related to study treatment administration, excluding toxicities clearly not related to the drug, such as disease progression, environmental factors, unrelated trauma, etc.
Efficacy Phase: Number of participants who experience one or more AEs
Time frame: Up to approximately 74 months
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.
Efficacy Phase: Number of participants who discontinue study treatment due to an AE
Time frame: Up to approximately 74 months
An AE is any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a study intervention.
Efficacy Phase: Objective Response Rate (ORR)
Time frame: Up to approximately 74 months
ORR is defined as the percentage of participants with Complete Response (CR: disappearance of all target lesions) or Partial Response (PR: at least a 30% decrease in the sum of diameters of target lesions) per Response Evaluation Criteria In Solid Tumors Version 1.1 (RECIST 1.1). The percentage of participants who experience CR or PR as assessed by Blinded Independent Central Review (BICR) will be presented.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- include but are not limited to the following:
- Has a histologically confirmed diagnosis of unresectable locally advanced/metastatic RCC with clear cell component (with or without sarcomatoid features).
- Has received no other prior systemic therapy for treatment of advanced/metastatic ccRCC except for adjuvant (PD-(L)1) therapy.
- Has disease recurrence during adjuvant anti- PD-(L)1 therapy or ≤24 months following the last dose of adjuvant anti-PD-(L)1 therapy.
- Has measurable disease per RECIST 1.1 as assessed by investigator and verified by BICR.
- Is able to swallow oral medication.
- Submits an archival tumor tissue sample or newly obtained core or excisional biopsy of a tumor lesion not previously irradiated.
- Participants receiving bone resorptive therapy (must have therapy initiated at least 2 weeks before allocation/randomization).
- Has adequately controlled blood pressure (BP) with or without antihypertensive medications, defined as BP ≤140/90
Where
- San Francisco, California
- Mineola, New York
- New York, New York
- Durham, North Carolina
- Pittsburgh, Pennsylvania
- Nashville, Tennessee
Collaborators
Exelixis
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 10, 2026 · Source of record for eligibility and locations