NCT06525220 · Merus N.V.
A Phase 3 Study to Evaluate Petosemtamab Plus Pembrolizumab vs Pembrolizumab in First-line Treatment of Head and Neck Cancer (LiGeR - HN1)
What this study is about
This is a Phase 3 randomly assigned, where both patients and doctors know the treatment given study to evaluate the effectiveness and safety of petosemtamab plus pembrolizumab vs pembrolizumab in first-line treatment of recurrent or metastatic PD-L1+ head and neck squamous cell carcinoma.
View original scientific description
This is 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.
Interventions
DRUG
Petosemtamab
MCLA-158
DRUG
Pembrolizumab
Humanized Antibody
Primary outcome measures
Overall Survival (OS)
Time frame: Up to approximately 3 years
Objective Response Rate (ORR) per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 as assessed by blinded independent central review (BICR)
Time frame: Up to approximately 2 years
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
- Signed ICF before initiation of any study procedures 2. Age ≥ 18 years at signing of ICF 3. Histologically confirmed HNSCC with evidence of metastatic or locally recurrent disease not amenable to local therapy with curative intent. 4. The eligible HNSCC primary tumor locations are oropharynx, oral cavity, hypopharynx, and larynx. 5. HNSCC patients eligible to receive pembrolizumab as 1L monotherapy with tumors expressing PD-L1, CPS ≥1. 6. HNSCC patients should not have had previous systemic therapy administered in the incurable recurrent or metastatic setting 7. A new tumor biopsy, unless the patient has an available archival tumor sample with sufficient material 8. Measurable disease per Investigator assessment as defined by RECIST v1.1 by radiologic methods 9. ECOG Performance Status (PS) of 0-1 10. Life expectancy ≥ 12 weeks, as per investigator assessment. 11. Left ventricular ejection fraction (LVEF) ≥50% or ≥ institutional normal limit, whichever is higher
Where
- Mobile, Alabama
- La Jolla, California
- Los Angeles, California
- Palo Alto, California
- Newark, Delaware
- Washington D.C., District of Columbia
- Fort Myers, Florida
- Orlando, Florida
- St. Petersburg, Florida
- West Palm Beach, Florida
- Atlanta, Georgia
- Chicago, Illinois
And 21 more locations — see the full list below.
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 Jun 2, 2026 · Source of record for eligibility and locations