Merus Announces Publication of an Abstract on Petosemtamab as 2L+ treatment of r/m HNSCC at the ESMO Asia Congress 2024

In This Article:

Merus N.V.
Merus N.V.

– Petosemtamab 1500 mg monotherapy phase 2 interim data continues to demonstrate clinically meaningful activity in 2L+ HNSCC

– Conference call on Saturday, Dec. 7 at 9:00 a.m. ET to discuss full data set

UTRECHT, The Netherlands and CAMBRIDGE, Mass., Dec. 01, 2024 (GLOBE NEWSWIRE) -- Merus N.V. (Nasdaq: MRUS) (Merus, the Company, we, or our), a clinical-stage oncology company developing innovative, full-length multispecific antibodies (Biclonics® and Triclonics®), today announced the publication of an abstract regarding petosemtamab, a Biclonics® targeting EGFR and LGR5, in previously treated (2L+) patients (pts) with recurrent/metastatic head and neck squamous cell carcinoma (r/m HNSCC) on the European Society for Medical Oncology (ESMO®) Asia Congress website. The abstract presents updated clinical data on petosemtamab from the initial expansion cohort (1500 mg) and a new dose-comparison cohort (1100 mg vs. 1500 mg) in 2L+ HNSCC for presentation at the ESMO® Asia Congress 2024 taking place in Singapore, Dec. 6-8, 2024.

The presentation will be discussed on a conference call on Saturday, December 7, at 9:00 a.m. ET. The presentation will include interim data from a later data cutoff date with additional patients evaluable for response and more mature duration of treatment information.

“Petosemtamab 1500 mg monotherapy continues to demonstrate consistent, durable, and clinically meaningful efficacy in 2L+ r/m HNSCC, underscoring its potential to become a new standard of care,” said Fabian Zohren, M.D., Ph.D., Chief Medical Officer of Merus. “We are looking forward to our upcoming presentation which will include new information with updated efficacy and safety of the larger, combined 2L+ dataset.”

Presentation title: Petosemtamab (MCLA-158) monotherapy in previously treated (2L+) recurrent/metastatic (r/m) head and neck squamous cell carcinoma (HNSCC): Phase 2 trial

Observations in the abstract include:

  • As of a November 6, 2023 data cutoff date 54 pts were treated with 1500 mg Q2W in the expansion cohort reported initially at AACR® 2023

    • 47* pts were evaluable for response (≥4 months follow up prior to data cutoff date and ≥1 post baseline scan, or early progressive disease (PD)) and overall response rate was 40.4% (19/47 and 1 unconfirmed partial response (PR) that confirmed post cutoff, 20/47) by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. per investigator assessment

    • 7.2 months median duration of response

    • 5.1 months median progression free survival

    • 12.5 months median overall survival

  • As of a March 6, 2024 data cutoff date, 42 pts were randomized to the 1500 mg vs. 1100 mg dose comparison cohort

    • At 1500 mg, 12 pts were evaluable for response, 5 responses were observed including 1 complete response, 3 PRs, and 1 unconfirmed PR (confirmed post cutoff)

    • At 1100 mg, 10 pts were evaluable for response with 1 confirmed PR observed

  • Petosemtamab was well tolerated at both dose levels; no new safety signals observed

    • No grade 5 treatment emergent adverse events were reported