Metsera's Obesity Drug Shows Promise, Strengthening Pfizer's $4.9 Billion Acquisition

Metsera's experimental obesity drug MET-097i has demonstrated significant weight loss results in a Phase 2 trial, bolstering Pfizer's recent decision to acquire the company for $4.9 billion. The study outcomes, announced Monday, reveal a weight reduction profile comparable to Eli Lilly's Zepbound, positioning Pfizer to potentially compete in the rapidly expanding obesity treatment market.

Phase 2 Trial Results and Tolerability Profile

In the 28-week Phase 2 trial, participants receiving the highest dose of MET-097i experienced an average weight loss 14 percentage points greater than those on placebo. This placebo-adjusted weight reduction aligns closely with the 13% achieved by Zepbound at a similar stage in its Phase 3 Surmount-1 study, according to Leerink Partners analyst David Risinger.

Notably, Metsera reported that only two of the 239 study volunteers withdrew due to side effects, suggesting a potentially favorable tolerability profile. An interim analysis of a separate ongoing trial evaluating a titrated dosing regimen showed promising results in mitigating common gastrointestinal side effects associated with GLP-1 drugs.

Comparison to Existing Treatments

The titrated dosing trial, utilizing a three-step regimen culminating in a 1.2 milligram injection, demonstrated lower rates of nausea and vomiting compared to Zepbound. Specifically, nausea and vomiting rates were 13 and 11 percentage points higher than placebo, respectively, with minimal association with diarrhea. In contrast, Zepbound's prescribing information cites nausea rates up to 21 points higher than placebo, diarrhea up to 15 points higher, and vomiting up to 11 points higher.

These findings suggest that MET-097i could potentially offer a "better than tirzepatide" tolerability profile, as noted by analyst David Risinger. The ability to minimize gastrointestinal side effects is crucial, as these often lead patients to discontinue GLP-1 drugs for obesity.

Implications for Pfizer and Market Competition

The positive trial results come just one week after Pfizer announced its agreement to acquire Metsera for $4.9 billion. This acquisition marks Pfizer's re-entry into the obesity drug development arena, following the company's previous decision to scrap two internal prospects due to safety concerns.

With the obesity treatment market projected to exceed $100 billion in annual sales by the next decade, Pfizer's strategic move positions the company to compete with established players like Eli Lilly and Novo Nordisk. The deal is expected to close before the end of the year, at which point Pfizer will likely oversee the advancement of MET-097i into more definitive Phase 3 studies to measure long-term weight loss effects.

As the pharmaceutical industry continues to focus on developing improved obesity treatments, Metsera's promising results and Pfizer's substantial investment highlight the growing importance and potential of this therapeutic area. The successful development and commercialization of MET-097i could significantly impact the competitive landscape of obesity treatment in the coming years.