Eli Lilly Expands GI Pipeline With New Phase 2 Brenipatide Trial in IBS-D and IBS-C

Eli Lilly Expands GI Pipeline With New Phase 2 Brenipatide Trial in IBS-D and IBS-C

Eli Lilly and Company (LLY) is running a Phase 2 trial called “A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of Brenipatide in the Treatment of Adult Participants With IBS-D.” The goal is to see how well brenipatide works and how safe and tolerable it is for adults with irritable bowel syndrome with diarrhea (IBS-D), a large and often underserved market.

The treatment under study is brenipatide (LY3537031), a drug given as an under‑the‑skin injection. It is being tested against a matching placebo shot to see if it can ease IBS-D symptoms and improve day‑to‑day quality of life for patients.

The trial is an interventional study where participants are randomly assigned to either brenipatide or placebo. It is double‑blind, meaning neither patients nor study doctors know who gets which treatment, and the main aim is to test brenipatide as a potential new therapy rather than just observe outcomes.

The study was first submitted on April 16, 2026, marking the formal start of the clinical program for this indication. The latest update was filed on May 11, 2026, signaling that the protocol details are current and that the trial is actively moving through the recruitment phase.

IBS-D Study Details

IBS-C Study Details