A phase 3 randomized, open-label study to evaluate the efficacy and safety of petosemtamab plus pembrolizumab vs pembrolizumab in first-line treatment of recurrent or metastatic PD-L1+ head and neck squamous cell carcinoma.

Status

Recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTIS

Registry ID

CTIS2023-510323-30-00

Acronym

MCLA-158-CL03

Enrollment

374

Registered

2024-08-27

Start date

2025-01-24

Completion date

Unknown

Last updated

2026-01-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

First-line treatment of recurrent or metastatic PD-L1+ head and neck squamous cell carcinoma.

Brief summary

1. Objective response rate (ORR), 2. Overall survival (OS)

Detailed description

1. PFS per RECIST v1.1 as assessed by investigator review, 2. The Duration of Response (DoR) per RECIST v1.1 and by investigator review, 3. The Clinical Benefit Rate (CBR) per RECIST v1.1 and by investigator review, 4. Percentage of participants with PFS at visit 1 and visit 2 per RECIST v1.1 as assessed by BICR

Interventions

DRUGPEMBROLIZUMAB

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Design outcomes

Secondary

Measure	Time frame
1. PFS per RECIST v1.1 as assessed by investigator review, 2. The Duration of Response (DoR) per RECIST v1.1 and by investigator review, 3. The Clinical Benefit Rate (CBR) per RECIST v1.1 and by investigator review, 4. Percentage of participants with PFS at visit 1 and visit 2 per RECIST v1.1 as assessed by BICR	—

Primary

Measure	Time frame
1. Objective response rate (ORR), 2. Overall survival (OS)	—

Countries

Belgium, Czechia, France, Germany, Greece, Hungary, Italy, Lithuania, Netherlands, Poland, Portugal, Spain

Outcome results

None listed

Source: EU CTIS · Data processed: Feb 4, 2026