Phase 1ab Study of LY4257496 Radioligand Therapy for Adults With GRPR-Positive Advanced Solid Tumors Including Breast, Colorectal, Prostate, Endometrial, Esophageal, and Stomach Cancer

What this Trial Is About

Researchers are studying LY4257496, a radioligand therapy, to evaluate its safety, tolerability, and effectiveness alone or combined with standard cancer treatments in adults with advanced cancers that test positive for Gastrin-releasing Peptide Receptor GRPR. These cancers include breast, colorectal, prostate, endometrial, esophageal, gastroesophageal junction, and stomach cancers. The study also assesses LY4257529 to identify tumors with high GRPR levels. This Phase 1 study aims to find the best dose and response to treatment. Participants will receive LY4257496 administered intravenously, either alone or along with standard anticancer therapies like Fulvestrant, Imlunestrant, Aromatase Inhibitors, Capecitabine, or Abemaciclib. The study has different groups receiving varying doses or combinations, including dose escalation and dose optimization phases. LY4257529 will be administered intravenously at select sites to help identify GRPR-positive tumors. Treatment cycles last 28 days, with follow-up extending to about 42 weeks. During the study, participants will undergo imaging tests such as CT or MRI to monitor tumor response and confirm measurable lesions. Researchers will track safety by monitoring dose-limiting toxicities and drug levels in the body. Participants will have regular clinic visits for treatment administration, laboratory tests, and evaluations. The main outcome is the maximum tolerated dose and the percentage of participants showing tumor shrinkage. Participation may last up to 36 weeks or until the tumor progresses.

A Study of LY4257496 in Participants With Cancer (OMNIRAY)