The biotechnology firm Immunome announced on Wednesday that the initial patient has been dosed in the Phase 1 clinical trial for its potential first-in-class antibody-drug conjugate, IM-1617. This drug targets an undisclosed solid tumor antigen and is intended for patients with advanced solid tumors.

IM-1617 is an antibody-drug conjugate directed against solid tumors, targeting a receptor tyrosine kinase that promotes tumor cell survival and mediates immune cell exclusion. The drug is conjugated with Immunome's proprietary topoisomerase I inhibitor, HC74, as its payload. The company's President and CEO stated that completing the first patient dosing is a significant milestone for its antibody-drug conjugate platform and a meaningful advancement of its mission to deliver targeted therapies for cancer patients.

This open-label, multi-center Phase 1 trial consists of dose escalation and dose expansion phases. It is designed to determine the safety, tolerability, pharmacokinetic profile, and preliminary anti-tumor activity of IM-1617. The study is expected to enroll patients with advanced solid tumors such as colorectal cancer, non-small cell lung cancer, and breast cancer. Preclinical in vivo efficacy studies demonstrated that IM-1617 achieved significant tumor regression after a single dose in multiple solid tumor models.

IM-1617 is the third antibody-drug conjugate from Immunome to enter clinical development. The company previously advanced IM-1021, targeting ROR1, into Phase 1 trials, and its radiopharmaceutical therapy targeting FAP, IM-3050, has received clearance for an Investigational New Drug application. Furthermore, the company's pipeline includes varegacestat, a gamma secretase inhibitor for which a New Drug Application has been submitted to the U.S. Food and Drug Administration. Immunome plans to submit Investigational New Drug applications for two additional antibody-drug conjugates, IM-1340 and IM-1335, by mid-2026 and late 2026, respectively.