Metsera's Amylin-Targeting Obesity Drug Shows Promise in Early Trial

Metsera, a rising star in the pharmaceutical industry, has reported encouraging results from a Phase I clinical trial of its experimental weight loss drug MET-233i. The ultra-long-acting amylin injection demonstrated significant weight loss potential and a favorable safety profile, potentially positioning the company as a strong competitor in the rapidly evolving obesity treatment market.

Clinical Trial Results and Market Impact

In a Phase I study involving 80 overweight or obese patients without type 2 diabetes, MET-233i showed an average weight reduction of 8.4% relative to placebo at 36 weeks, with some individual responses reaching as high as 10.2%. The highest dose tested, consisting of five weekly 1.2-mg shots, resulted in 8% weight loss after just 36 days.

These promising results have had a substantial impact on Metsera's market position. The company's shares rose as much as 20% following the announcement, with early trading on Monday seeing a 10% increase to around $30 per share. This positive market response is particularly noteworthy given Metsera's recent initial public offering (IPO) in January 2025, which raised $275 million and stands as the largest new stock offering in the biotech sector this year.

MET-233i: A Potential Game-Changer in Obesity Treatment

MET-233i's development represents a significant step in the evolution of obesity treatments. Unlike the more established GLP-1 drugs, such as Novo Nordisk's Wegovy and Eli Lilly's Zepbound, MET-233i targets the hormone amylin. This alternative mechanism of action could potentially offer several advantages, including better tolerability and lower loss of lean mass.

A key feature of MET-233i is its ultra-long-acting profile. Pharmacokinetic analysis revealed a half-life of 19 days, supporting a once-monthly dosing regimen. This extended duration of action could provide a significant competitive advantage in the marketplace, offering patients a more convenient treatment option.

The safety profile of MET-233i appears promising, with no severe or serious toxicities reported to date. While gastrointestinal side effects were observed, they were primarily confined to the first week of dosing, suggesting a rapid onset of tolerance.

The Expanding Landscape of Obesity Treatments

Metsera's advancement of MET-233i comes amid intensifying competition in the obesity treatment space. Major pharmaceutical companies are actively developing amylin-targeting therapies, recognizing the potential of this approach.

Novo Nordisk, a leader in the weight loss market, is developing CagriSema, a combination of its blockbuster GLP-1 drug semaglutide with the long-acting amylin analog cagrilintide. However, recent Phase III results for CagriSema have fallen short of analyst expectations, potentially creating an opportunity for competitors like Metsera.

Other notable players in the amylin-targeting obesity treatment field include Eli Lilly, which expects Phase II readout for eloralintide in mid-2025, and AbbVie, which recently entered the space through a potential $2.2 billion deal with Denmark's Gubra.

As the obesity treatment landscape continues to evolve, Metsera's MET-233i represents a promising new entrant with the potential to address unmet needs in this rapidly growing market. The company plans to continue its monotherapy study for MET-233i, with topline findings expected later this year, while also testing the amylin injection in combination with its ultra-long-acting GLP-1 therapy MET-097i.