Approval Probability
TA Base Rate
Adjusted LOA
ML Risk
Also known as MCLA-158
Petosemtamab · 3 trials · 8 indications
Evaluation of the number and severity of participants with treatment related toxicities observed during the dose escalation.
Incidence, severity, and relationship of AEs and SAEs
Treatment discontinuations due to AEs and dose modifications due to AEs
Evaluation of clinical benefit assessed by RECIST v1.1 determining Best overall response (BOR)
Evaluation of clinical benefit assessed by RECIST v1.1 determining objective response rate (ORR)
Incidence of TEAEs at Week 8
Bioavailability of subcutaneous vs intravenous administration
Area under the concentration versus time curve from time zero to time t \[AUC0-t\]
Maximum plasma concentration as measured from all individual plasma concentrations
Minimum plasma concentration as measured from all individual plasma concentrations
| Arm | Type | Description |
|---|---|---|
| Petosemtamab + Pembrolizumab | EXPERIMENTAL | Combination Therapy |
| Pembrolizumab | ACTIVE_COMPARATOR | Monotherapy |
| MCLA-158 | EXPERIMENTAL | - |
| Investigator's Choice | ACTIVE_COMPARATOR | - |
| MCLA-158 (Single-Agent) | EXPERIMENTAL | In Part 1, the dose escalation phase, patients with metastatic CRC will receive escalating doses of MCLA-158 (every 2 weeks) until MTD or RP2D is reached. Each Cycle is 28 days. Single agent treatment. In Part 2, the expansion phase, participants with metastatic CRC and certain other solid tumors will receive intravenous infusion (i.v.) of MCLA-158 at the recommended Phase II dose (RP2D) every 2 weeks, at Day 1 and Day 15. The duration of each treatment cycle is 28 days. In addition, in the expansion phase, one randomized cohort will evaluate 2 doses (1100 mg and 1500 mg) of MCLA-158 in head and neck squamous cell carcinoma patients. Also in the expansion phase, a subcutaneous formulation of MCLA-158 will be evaluated. |
| MCLA-158 + Pembrolizumab | EXPERIMENTAL | MCLA-158 in combination with pembrolizumab will be explored first in head and neck squamous cell carcinoma patients eligible to receive pembrolizumab as first-line monotherapy. |
| MCLA-158 + FOLFIRI combination chemotherapy | EXPERIMENTAL | MCLA-158 in combination with FOLFIRI will be explored in mCRC patients with up to 1 line of prior regimen. |
| MCLA-158 + FOLFOX combination chemotherapy | EXPERIMENTAL | MCLA-158 in combination with FOLFOX will be explored in mCRC patients with up to 1 line of prior regimen. |
| Name | Type | Description |
|---|---|---|
| Petosemtamab | DRUG | MCLA-158 |
| Pembrolizumab | DRUG | Humanized Antibody |
| Investigator's Choice | DRUG | Cetuximab |
| MCLA-158 | DRUG | full-length IgG1 bispecific antibody targeting EGFR and LGR5 |
| MCLA-158 + Pembrolizumab | COMBINATION_PRODUCT | MCLA-158 in combination with pembrolizumab will be explored first in HNSCC patients eligible to receive pembrolizumab as first-line monotherapy. |
| MCLA-158 + FOLFIRI | COMBINATION_PRODUCT | MCLA-158 in combination with FOLFIRI will be explored in mCRC patients with up to 1 line of prior regimen. |
| MCLA-158 + FOLFOX | COMBINATION_PRODUCT | MCLA-158 in combination with FOLFOX will be explored in mCRC patients with up to 1 line of prior regimen. |
Inclusion Criteria: 1. 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 location...
Petosemtamab is an investigational monoclonal antibody being studied in advanced or metastatic solid tumors and head and neck squamous cell carcinoma. It is being evaluated both as a first-line combination treatment with pembrolizumab and as a monotherapy in previously treated head and neck cancer patients. It is not approved for any indication.
Petosemtamab is developed by Merus N.V., a clinical-stage oncology company that trades on the Nasdaq under the ticker MRUS. Merus is running the clinical program for the drug across head and neck squamous cell carcinoma and other advanced solid tumors.
Petosemtamab is in Phase 3 clinical development for head and neck squamous cell carcinoma, with two active Phase 3 trials, LiGeR-HN1 and LiGeR-HN2. An earlier Phase 1 study in advanced solid tumors is also ongoing. The drug remains investigational and has not been approved by the FDA.
Petosemtamab is being studied in three registered trials. NCT06525220 (LiGeR-HN1) is a Phase 3 study of petosemtamab plus pembrolizumab versus pembrolizumab in first-line head and neck cancer. NCT06496178 (LiGeR-HN2) is a Phase 3 study versus investigator's choice monotherapy in previously treated patients. NCT03526835 is a Phase 1 study in advanced solid tumors.
Yes, petosemtamab and MCLA-158 are the same investigational drug. MCLA-158 was the earlier code name used by Merus, and petosemtamab is the current international nonproprietary name. Both names refer to the same monoclonal antibody being studied in head and neck squamous cell carcinoma and advanced solid tumors.
Across the three registered petosemtamab trials, total planned enrollment is approximately 1,320 patients. The two Phase 3 head and neck cancer studies plan to enroll 699 and 621 patients respectively, while the Phase 1 advanced solid tumor study plans to enroll 560 patients.