Mersana Therapeutics Announces Upcoming Oral Presentation of Emi-Le Clinical Data at European Society for Medical Oncology (ESMO) Breast Cancer 2025 Annual Congress

CAMBRIDGE, Mass., April 01, 2025 (GLOBE NEWSWIRE) — Mersana Therapeutics, Inc. (NASDAQ: MRSN), a clinical-stage biopharmaceutical company focused on discovering and developing a pipeline of antibody-drug conjugates (ADCs) targeting cancers in areas of high unmet medical need, today announced that Phase 1 dose escalation and backfill cohort clinical data for emiltatug ledadotin (Emi-Le; XMT-1660) will be presented in an oral session at the ESMO Breast Cancer 2025 Annual Congress, which is being held from May 14-17, 2025, in Munich, Germany.

Oral Presentation Details

Title: Clinical Activity of Emiltatug Ledadotin (Emi-Le), a B7-H4-Directed ADC, in Patients with TNBC who Received at Least One Prior Topoisomerase-1 Inhibitor (Topo-1) ADC

Session Title: Mini Oral Session 1

Date and Time: Thursday, May 15, 2025 from 8:30-10:00 a.m. CEST

Abstract Number: 298MO

Presenter: Erika Hamilton, M.D., Director Breast Cancer Research, Sarah Cannon Research Institute in Nashville, Tennessee

About Emi-Le
Emi-Le is a B7-H4-directed Dolasynthen ADC with a precise, target-optimized drug-to-antibody ratio (DAR 6) and a proprietary auristatin payload with controlled bystander effect. This candidate is being investigated in a Phase 1 dose escalation and expansion trial in patients with solid tumors, including breast, endometrial and ovarian cancers as well as adenoid cystic carcinoma type 1. In the initial clinical data that were reported as of a December 13, 2024 data cutoff, Emi-Le was observed to be generally well tolerated with differentiated safety and tolerability profile. Additionally, confirmed objective responses were observed across all enrolled tumor types, including in patients with triple negative breast cancer (TNBC) who had previously been treated with a topoisomerase-1 inhibitor (topo-1) ADC.

The U.S. Food and Drug Administration has granted two Fast Track designations to Emi-Le for the treatment of 1) adult patients with advanced or metastatic triple-negative breast cancer, and 2) advanced or metastatic breast cancer in patients with human epidermal growth factor receptor 2 (HER2) low (IHC 1+ or IHC 2+/ISH–) or HER2-negative (IHC 0) disease, including TNBC, who have received a prior topo-1 ADC. For more information about Mersana’s ongoing Phase 1 trial of Emi-Le, please visit clinicaltrials.gov (NCT05377996).

About Mersana Therapeutics
Mersana Therapeutics is a clinical-stage biopharmaceutical company focused on the development of novel antibody-drug conjugates (ADCs) and driven by the knowledge that patients are waiting for new treatment options. The company has developed proprietary cytotoxic (Dolasynthen) and immunostimulatory (Immunosynthen) ADC platforms that are generating a pipeline of wholly-owned and partnered product candidates with the potential to treat a range of cancers. Its pipeline includes Emi-Le (emiltatug ledadotin; XMT-1660), a Dolasynthen ADC targeting B7-H4, and XMT-2056, an Immunosynthen ADC targeting a novel epitope of human epidermal growth factor receptor 2 (HER2). Mersana routinely posts information that may be useful to investors on the “Investors & Media” section of its website at www.mersana.com.

Contact:
Jason Fredette
617-498-0020
jason.fredette@mersana.com