Metsera, Inc. announced positive Phase 1 clinical trial data for MET-233i, a new ultra-long-acting amylin analog designed for monthly dosing. The trial showed up to 8.4% mean placebo-subtracted weight loss at day 36 and a 19-day observed half-life, supporting once-monthly dosing, with a favorable tolerability profile. This positions MET-233i as a potential best-in-class amylin therapy and a promising component of a combination treatment with Metsera’s GLP-1 receptor agonist, MET-097i.
This news is potentially game-changing for the obesity and metabolic disease treatment landscape. The extended half-life of MET-233i addresses a significant limitation of current amylin analogs, which require weekly injections. Monthly dosing can greatly enhance patient adherence and convenience, potentially leading to better weight loss outcomes. The combination of MET-233i with MET-097i could offer a powerful, first-in-category monthly multi-NuSH combination therapy with enhanced efficacy compared to existing options.
In the Phase 1 trial, MET-233i displayed dose-dependent weight loss, reaching a maximum of 8.4% placebo-subtracted mean reduction at day 36 with the 1.2 mg dose. Importantly, even single doses led to substantial weight loss maintained for over four weeks, highlighting the drug’s long-acting nature. Gastrointestinal side effects were mild, dose-dependent, and largely limited to the first week, suggesting rapid tolerance development. Furthermore, no severe or serious adverse events were observed. The 19-day half-life and matched exposure profile with MET-097i underscore the feasibility of a monthly combination therapy.
These positive Phase 1 results pave the way for further clinical development of MET-233i, both as a standalone therapy and in combination with MET-097i. Ongoing trials are evaluating the efficacy and safety of 12 weekly doses followed by a monthly maintenance dose of MET-233i, as well as the combination of MET-233i and MET-097i over 12 weeks. Data from these trials are expected by late 2025 and early 2026, respectively. These developments could significantly impact the treatment paradigm for obesity and related metabolic disorders, offering patients more effective and convenient therapeutic options. The success of MET-233i, particularly in combination with MET-097i, could solidify Metsera’s position as a leader in developing innovative metabolic disease treatments.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
