Trial results for the Phase 1/2 study (NCT03179436) investigating quavonlimab in combination with pembrolizumab in participants with advanced solid tumors were posted on ClinicalTrials.gov on 2025-04-08. The study assessed safety and tolerability, reporting dose-limiting toxicities (DLTs) that ranged from 0.0% to 13.3% across various cohorts and arms.
Background
The study investigated quavonlimab in combination with pembrolizumab for the treatment of advanced solid tumors. The trial aimed to assess the safety, tolerability, pharmacokinetics (PK), and preliminary efficacy of escalating doses of quavonlimab when used with pembrolizumab.
Trial design
The MK-1308-001 study (NCT03179436) was a Phase 1/2, dose-escalation and expansion trial that enrolled 415 participants. The study investigated quavonlimab in combination with pembrolizumab in participants with advanced solid tumors. The trial's objective included assessing the safety, tolerability, and pharmacokinetics of the combination, as well as preliminary efficacy.
Key results
The trial reported on the percentage of participants experiencing dose-limiting toxicities (DLTs) and the number of participants with at least one adverse event (AE) across different treatment cohorts and arms:
- For the outcome "Percentage of Participants With ≥1 Dose Limiting Toxicity (DLT)":
- Cohort 1 (MK-1308 25 mg Q3W + Pembro. 200 mg Q3W) reported 0.0% of participants with ≥1 DLT.
- Cohort 2 (MK-1308 75 mg Q3W + Pembro. 200 mg Q3W) reported 13.3% of participants with ≥1 DLT.
- Cohort 3 (MK-1308 200 mg Q3W + Pembro. 200 mg Q3W) reported 0.0% of participants with ≥1 DLT.
- Arm A (MK-1308 25 mg Q3W + Pembro. 200 mg Q3W) reported 7.5% of participants with ≥1 DLT.
- Arm B (MK-1308 25 mg Q6W + Pembro. 200 mg Q3W) reported 5.0% of participants with ≥1 DLT.
- Arm C (MK-1308 75 mg Q6W + Pembro. 200 mg Q3W) reported 10.0% of participants with ≥1 DLT.
- Arm D (MK-1308 75 mg Q6W + Pembro. 200 mg Q3W) reported 10.0% of participants with ≥1 DLT.
- Arm E (MK-1308 75 mg Q3W + Pembro. 200 mg Q3W) reported 7.1% of participants with ≥1 DLT.
- For the outcome "Number of Participants With ≥1 Adverse Event (AE)":
- Cohort 1 (MK-1308 25 mg Q3W + Pembro. 200 mg Q3W) reported 14 participants with ≥1 AE.
- Cohort 2 (MK-1308 75 mg Q3W + Pembro. 200 mg Q3W) reported 17 participants with ≥1 AE.
- Cohort 3 (MK-1308 200 mg Q3W + Pembro. 200 mg Q3W) reported 8 participants with ≥1 AE.
- Arm A (MK-1308 25 mg Q3W + Pembro. 200 mg Q3W) reported 39 participants with ≥1 AE.
The key analyses section also reported a "Percent Difference" of 2.4 (95.0% CI: -8.7 to 14.1), though the specific outcome to which this analysis refers was not provided in the data.
What this means
The posted results from the Phase 1/2 study indicate that the combination of quavonlimab and pembrolizumab demonstrated varying but generally manageable dose-limiting toxicities across different dosing cohorts and arms in participants with advanced solid tumors. The presence of DLTs in some cohorts, such as 13.3% in Cohort 2, suggests that dose optimization and careful monitoring are important considerations for this combination therapy. The overall reporting of adverse events also provides initial insights into the safety profile of this investigational regimen.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03179436, titled "Study of Quavonlimab (MK-1308) in Combination With Pembrolizumab (MK-3475) in Advanced Solid Tumors (MK-1308-001)," were posted on 2025-04-08 on clinicaltrials.gov.