Eli Lilly has pulled the plug on a phase 2b obesity trial before enrolling a single patient, citing “strategic business reasons.” The study was designed to test bimagrumab, an asset Lilly acquired in its $1.9 billion Versanis buyout, as a single agent and in combination with blockbuster GLP-1/GIP drug tirzepatide.
Lilly filed to run the study in March. At that time, the company was planning to enroll 180 people with obesity or who are overweight plus Type 2 diabetes to test the effects of bimagrumab, an antibody that binds activin type II A and B receptors to block activin and myostatin signaling. The study featured nine arms to test various regimens of bimagrumab and tirzepatide, the active ingredient in Mounjaro and Zepbound.
However, as first reported by Bloomberg News, Lilly has axed the trial. An early sign that something was amiss emerged in June, when the company changed the status of the study on ClinicalTrials.gov from “not yet recruiting” to “active, not recruiting.”
Lilly changed the trial’s status again, this time to “withdrawn,” in an update that went live Wednesday. To explain the update, the company said the trial was terminated for strategic business reasons. Lilly told Fierce Biotech in a short, emailed statement that it “routinely evaluate(s) our clinical development programs to optimize the potential for each product.”
The pharma added that bimagrumab is still “currently being studied in an ongoing phase 2 trial with tirzepatide, alone or in combination, in patients with obesity. Results from this trial will be available in 2026.”
The first change to the status of the withdrawn trial coincided with the publication of data from a phase 2 study that tested bimagrumab in combination with semaglutide, the GLP-1 drug Novo Nordisk sells as Ozempic and Wegovy.
In a presentation at the American Diabetes Association’s Scientific Sessions in June, researchers hailed a “very striking difference” in the proportion of weight loss from fat in the combination arm. Fat accounted for around 72% of weight loss in patients who took semaglutide as a monotherapy. The figure jumped to above 90% in the combination cohort.
Versanis began the semaglutide combination trial and tested an intravenous version of bimagrumab. Lilly switched to subcutaneous dosing for its trials of bimagrumab and swapped out Novo’s semaglutide for its own tirzepatide.
Editor's note: This story was updated at 10:40 a.m. ET to include comment from Lilly.