Merus Announces Petosemtamab in Metastatic Colorectal Cancer Abstract Selected for Plenary Session Oral Presentation at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics

-   Plenary session oral presentation: Friday, October 24 10:00 -11:40 a.m. ET

-   Poster presentation on preclinical evaluation of petosemtamab on cancer stem cells: Friday, October 24 12:30-4:00 p.m. ET

UTRECHT, The Netherlands and CAMBRIDGE, Mass., Oct. 13, 2025 (GLOBE NEWSWIRE) -- Merus N.V. (Nasdaq: MRUS) (Merus, the Company, we, or our), an oncology company developing innovative, full-length multispecific antibodies and antibody drug conjugates (Biclonics, Triclonics and ADClonics), today announced the acceptance of two abstracts on petosemtamab, a Biclonics targeting EGFR and LGR5, for presentation at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, being held in Boston, Massachusetts on October 22-26, 2025.

Initial interim data from the phase 2 trial evaluating petosemtamab in combination with standard chemotherapy in 1L and 2L metastatic colorectal cancer (mCRC), and as monotherapy in heavily pretreated (3L+) mCRC will be presented in a plenary session by Dr. Moh’d Khushman M.D., Washington University School of Medicine, St. Louis, MO. Merus will also present a poster regarding the preclinical evaluation of petosemtamab on cancer stem cells.

Presentations:
Title: Petosemtamab (MCLA-158) monotherapy or with chemotherapy in metastatic colorectal cancer: Preliminary antitumor activity and safety data from a phase 2 trial
Session Title: Plenary Session 4: Clinical Trials Plenary Session
Date and Time: Friday, October 24 10:00-11:40 a.m. ET
The same data will also be available in a poster:
Session Title: Poster Session B
Session Date and Time: Friday, October 24, 12:30-4:00 p.m. ET

Poster presentation:
Title: Preclinical evaluation of petosemtamab, an epidermal growth factor receptor (EGFR) and leucine-rich repeat-containing G protein-coupled receptor (LGR5) bispecific antibody, on cancer stem cells
Session Title: Poster Session B
Session Date and Time: Friday, October 24, 12:30-4:00 p.m. ET

The abstracts will be available in the conference app on Wednesday, October 22, 2025 at 12:00 p.m. ET. The full presentations are planned to be available on the Merus website at the start of each session.

About Petosemtamab
Petosemtamab, or MCLA-158, is a Biclonics low-fucose human full-length IgG1 antibody targeting the epidermal growth factor receptor (EGFR) and the leucine-rich repeat containing G-protein-coupled receptor 5 (LGR5). Petosemtamab is designed to exhibit three independent mechanisms of action including inhibition of EGFR-dependent signaling, LGR5 binding leading to EGFR internalization and degradation in cancer cells, and enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) activity.