Lilly starts Phase 2 obesity trial of GIP drug macupatide
An experimental GIP receptor agonist has entered mid-stage testing in obesity, but no trial details or results have been released, leaving it years from any possible approval.
Eli Lilly has started a Phase 2 trial of macupatide in people with obesity, testing the experimental drug on its own and in combination with another therapy. The study, listed in trial records as NCT07589608, began May 15, 2026, in the United States and is given by subcutaneous injection, according to the drug's AdisInsight profile [1].
Macupatide, also called LY 3532226 and LAGIPRA, is described as a new molecular entity and a "gastric inhibitory polypeptide receptor agonist," meaning it is designed to act on the GIP receptor [1]. Its highest development phase is listed as Phase 2, for both obesity and type 2 diabetes [1].
The Phase 2 listing does not disclose how many participants will be enrolled, what doses are being tested, how long the study will run, or what macupatide is being combined with in the combination arms. Those details have not been reported [1]. No results from the obesity trial have been disclosed [1].
Lilly's other macupatide work is also tracked in the profile. On August 14, 2026, the company was reported to be planning a Phase 1 trial in obesity in Japan, with a start date of October 2026 and subcutaneous dosing; it is registered as NCT07765511 [1]. Macupatide is separately listed as reaching Phase 2 in type 2 diabetes [1]. For type 1 diabetes, no recent reports of Phase 1 development were identified in the United States as of July 28, 2026 [1].
Why it matters for patients
Macupatide is not an approved medicine. It is listed as an investigational new molecular entity in Phase 2 for obesity and type 2 diabetes, so it is not available by prescription, and no safety or weight-loss results from the Phase 2 obesity trial have been published [1]. People who currently take approved GLP-1 or related obesity medicines would see no change in their options from this trial's start.
Because the trial's size, dosing, duration and endpoints have not been reported, there is no way yet to judge how macupatide compares with existing treatments, or whether it will work at all in obesity [1]. The profile also does not say whether the Phase 2 study is still enrolling or at which sites, and that information has not been disclosed [1]. Whether macupatide will move into a larger Phase 3 program, and when, has not been reported [1].
What happens next
- The Phase 2 obesity trial (NCT07589608) began May 15, 2026; no completion date or timeline for results has been disclosed [1].
- A Phase 1 obesity trial in Japan (NCT07765511) is planned for October 2026 [1].
- The AdisInsight profile was last updated August 20, 2026; no further milestones for macupatide in obesity or type 2 diabetes have been reported since [1].
Sources
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