Pfizer acquires Metsera’s obesity portfolio in $4.9bn deal

December 2025 | DEALFRONT | MERGERS & ACQUISITIONS

Financier Worldwide Magazine

December 2025 Issue

Seeking to establish a stronger presence in the rapidly expanding obesity treatment market, multinational pharmaceutical and biotechnology corporation Pfizer has agreed to acquire clinical-stage biopharmaceutical company Metsera in a transaction valued at $4.9bn.

Under the terms of the definitive agreement, Pfizer will purchase all outstanding shares of Metsera common stock for $47.50 per share in cash at closing. The deal also includes a non-transferable contingent value right, which entitles holders to potential additional payments of up to $22.50 per share in cash, contingent upon the achievement of specific clinical and regulatory milestones. These milestones include the initiation of a phase three trial for Metsera’s GLP-1 and amylin combination therapy, and regulatory approvals for both monotherapy and combination treatments.

The global obesity drug market, projected to reach $150bn by the early 2030s, is being driven by the widespread adoption of GLP-1 therapies. Pharmaceutical companies are now competing to develop next-generation treatments that target additional hormones and aim to reduce fat while preserving muscle mass.

“Obesity is a large and growing space with over 200 health conditions associated with it,” said Albert Bourla, chairman and chief executive of Pfizer. “We are excited to apply our deep cardiometabolic experience and manufacturing and commercial infrastructure to accelerate a portfolio that includes potential best-in-class injectables, with clinical data differentiated by efficacy, tolerability and durability supporting monthly dosing, with the aim to address the ongoing unmet needs associated with obesity and related diseases.”

Founded in 2022 and headquartered in New York, Metsera is a clinical-stage biopharmaceutical company focused on developing next-generation medicines for obesity and cardiometabolic diseases. Its portfolio includes oral and injectable incretin, non-incretin and combination therapies designed to meet the evolving needs of the weight loss treatment landscape.

Metsera’s pipeline features four programmes in clinical development and several next-generation candidates undergoing investigational new drug-enabling studies. These are designed to reduce injection frequency while improving efficacy and tolerability. Its lead candidate, MET-097i, a GLP-1 receptor agonist, is currently in phase two trials for both weekly and monthly dosing. MET-233i, a monthly amylin analogue, is in phase one development and is being evaluated both as a monotherapy and in combination with MET-097i. Early data from the VESPER-1 trial showed weight loss of up to 14.1 percent after 28 weeks, with some participants losing as much as 26.5 percent.

“Since its founding, Metsera has worked tirelessly to reduce the physical, emotional and economic burdens of obesity with a portfolio of next generation nutrient-stimulated hormone therapeutic candidates,” said Whit Bernard, co-founder and chief executive of Metsera. “Our team has invented and developed multiple injectable and oral candidate medicines and a category-leading peptide engineering platform, which together promise class-leading performance in a major sector of population health.”

The boards of directors of both Metsera and Pfizer have unanimously approved the transaction.

Citi is acting as Pfizer’s financial adviser, with Wachtell, Lipton, Rosen & Katz providing legal counsel. Metsera’s financial advisers include Goldman Sachs & Co. LLC, Guggenheim Securities LLC, BofA Securities Inc. and Allen & Company LLC, with legal advice from Paul, Weiss, Rifkind, Wharton & Garrison LLP.

The transaction is expected to close in the fourth quarter of 2025, subject to customary closing conditions, including regulatory approvals and approval by Metsera’s shareholders. As of October 2025, the deal remains on track, with no reported delays in regulatory review.

“The acquisition sets a path for our portfolio to potentially transform the lives of hundreds of millions of people and represents an excellent outcome for our shareholders,” noted Mr Bernard. “We look forward to joining forces with Pfizer to leverage their global clinical, regulatory, manufacturing and commercial capabilities to realise the promise of improved human health at scale.”

Fraser Tennant