A Phase 1 interventional study of MK-4464 and Pembrolizumab in Advanced/Metastatic Solid Tumors and Neoplasms, sponsored by Merck Sharp & Dohme LLC. Completed at 6 sites in 4 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-10-09.
Sponsored by Merck Sharp & Dohme LLC · Phase 1, Interventional, and Treatment
The purpose of this study is to assess the safety, pharmacokinetics, and preliminary efficacy of MK-4464 as monotherapy and in combination with pembrolizumab in participants with advanced/metastatic solid tumors.
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This study's enrollment of 64 is above the median of 50 across 7,253 interventional studies indexed under Neoplasms.
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The key Inclusion Criteria include but are not limited to the following:
Exclusion Criteria:
The key Exclusion Criteria include but are not limited to the following:
Participants will receive an intravenous (IV) infusion of MK-4464 administered in escalating doses every 3 weeks for up to 35 cycles. Escalation to subsequent MK-4464 doses will be based on safety of previous dose.
Biological: MK-4464
Participants will receive an IV infusion of MK-4464 administered in escalating doses and a 200 mg IV infusion of Pembrolizumab every 3 weeks for up to 35 cycles. Escalation to subsequent MK-4464 doses will be based on safety of MK-4464 monotherapy arm.
Biological: MK-4464 · Biological: Pembrolizumab
Participants will receive an IV infusion of 89Zr-MK-4464 + IV infusion of MK-4464 on Cycle 1 Day 1, followed by an IV infusion of MK-4464 + a 200 mg IV infusion of pembrolizumab starting on Cycle 2 Day 1 and every 3 weeks for up to 35 cycles. Each cycle=3 weeks. MK-4464 doses will be based on safety of MK-4464 monotherapy arm. Participants may receive a 200 mg IV infusion of pembrolizumab on cycle 36.
Biological: MK-4464 · Biological: Pembrolizumab · Drug: 89Zr-MK-4464
MK-4464 administered as an IV infusion every three weeks according to allocation and dose escalation.
Pembrolizumab 200 mg administered as an IV infusion every three weeks.
89ZR-MK-4464 administered as an IV infusion on C1D1.
Number of Participants Experiencing Dose-Limiting Toxicities (DLTs)
A DLT is any toxicity assessed by the investigator to be possibly, probably, or definitely related to study intervention administration that results in a change to a given dose or a delay in initiating the next cycle. All toxicities will be graded using National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE).
Time frame: Up to approximately 21 days
Number of Participants Who Experience At Least One adverse event (AE)
An AE is defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who experience at least one AE will be presented.
Time frame: Up to approximately 27 months
Number of Participants Who Discontinue Study Treatment Due to an AE
An AE is defined as any untoward medical occurrence in a participant, temporally associated with the use of study treatment, whether or not considered related to the study treatment. The number of participants who discontinue study treatment due to an AE will be presented.
Time frame: Up to approximately 24 months
Minimum Plasma Concentration (Cmin) of MK-4464
Cmin is the minimum concentration of the drug observed in plasma. Blood samples will be collected pre-dose and post-dose at designated timepoints to determine Cmin of MK-4464.
Time frame: Once daily on Day 2, 3, 5, 8, 15 of Cycle 1 and 4, Pre-dose and immediately Post-dose Day 1 Cycle 1, 2, 3, 4, Pre-dose Day 1 Cycles 5, 6, 7, 8, and every 4 cycles thereafter through Cycle 35, 30 days post last dose (up to ~25 months); Cycle = 21 days
Maximum Plasma Concentration (Cmax) of MK-4464
Cmax is the maximum concentration of the drug observed in plasma. Blood samples will be collected pre-dose and post-dose at designated timepoints to determine Cmax of MK-4464.
Time frame: Once daily on Day 2, 3, 5, 8, 15 of Cycle 1 and 4, Pre-dose and immediately Post-dose Day 1 Cycle 1, 2, 3, 4, Pre-dose Day 1 Cycles 5, 6, 7, 8, and every 4 cycles thereafter through Cycle 35, 30 days post last dose (up to ~25 months); Cycle = 21 days
Area Under the Plasma Concentration-Time Curve (AUC) of MK-4464
AUC is a measure of the extrapolated mean concentration in serum. Blood samples will be collected pre-dose and post-dose at designated timepoints to determine AUC of MK-4464.
Time frame: Once daily on Day 2, 3, 5, 8, 15 of Cycle 1 and 4, Pre-dose and immediately Post-dose Day 1 Cycle 1, 2, 3, 4, Pre-dose Day 1 Cycles 5, 6, 7, 8, and every 4 cycles thereafter through Cycle 35, 30 days post last dose (up to ~25 months); Cycle = 21 days
Objective Response Rate (ORR)
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 investigator assessment will be presented.
Time frame: Up to 24 months
Plan to share: Yes — https://trialstransparency.msdclinicaltrials.com/pdf/ProcedureAccessClinicalTrialData.pdf
This study is completed, as verified in Oct 2025. You cannot join it, but the record below documents what was studied.
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