With its pending $7.3-billion deal to acquire the bio/pharmaceutical company, Metsera, Pfizer is making a strong play in the obesity drug market. What are the assets that Pfizer will be acquiring, and how do they stack up against the other notable contenders in the obesity drug market?

By Patricia Van Arnum, Editorial Director, DCAT, pvanarnum@dcat.org

The latest deal in the obesity drug market
This week (September 22, 2025), Pfizer made a move to up its position in the obesity drug market when it agreed to acquire Metsera, a New York-based clinical-stage bio/pharmaceutical company focused on obesity and cardiometabolic diseases, in deal worth up to $7.3 billion ($4.9 billion upfront plus a contingent value right for potential additional milestone payments of up to approximately $2.4 billion).

The pending acquisition provides Pfizer with a portfolio of differentiated oral and injectable incretin, non-incretin, and combination therapy candidates. Metsera has a portfolio of therapeutic candidates and combinations with four programs in clinical development and several programs with investigational new drug-enabling studies ongoing. These include: MET-097i, a weekly and monthly injectable glucagon-like peptide-1 (GLP-1) receptor agonist, both in Phase II development; MET-233i, a monthly amylin analog candidate being evaluated as a monotherapy and in combination with MET-097i in Phase I development; two oral GLP-1 receptor agonist candidates expected to begin clinical trials imminently (as reported on September 22, 2025); and additional preclinical nutrient-stimulated hormone therapeutics. The Boards of Directors of both Metsera and Pfizer have unanimously approved the transaction, which is expected to close in the fourth quarter of 2025, subject to the satisfaction of customary closing conditions, including receipt of required regulatory approvals and approval by Metsera’s shareholders. 

In making the move, Pfizer is countering a recent (April 2025) setback in its obesity drug portfolio when it announced it was discontinuing development of danuglipron, an oral GLP-1 receptor agonist, which was being investigated for chronic weight management, due to potential liver toxicity. Pfizer reported that its dose-optimization studies of once-daily formulations of danuglipron met key pharmacokinetic objectives and confirmed a formulation and dose with the potential to deliver a competitive efficacy and tolerability profile in Phase III testing, based on earlier studies of twice-daily danuglipron. Pfizer reported that while the overall frequency of liver enzyme elevations across the over 1,400 participant safety database of danuglipron was in line with approved agents in the class, a single asymptomatic participant in one of the dose-optimization studies experienced potential drug-induced liver injury that resolved after discontinuation of danuglipron. After a review of the totality of information, including all clinical data generated to date for danuglipron and recent input from regulators, Pfizer decided to discontinue development of the molecule.

Entering a competitive market
The leaders in the obesity drug market are Novo Nordisk and Eli Lilly and Company, who battle one-to-one in both the diabetes and obesity market with Novo’s Ozempic/Wegovy (semaglutide), a GLP-1 agonist, and Lilly’s Mounjaro/Zepbound (tirzepatide), a dual-activating GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 medication, respectively for treating Type 2 diabetes and obesity. For both Novo Nordisk’s Ozempic/Wegovy and Lilly’s Mounjaro/Zepbound, the obesity indication is a key driver driving blockbuster status for these drugs, which are administered as injectables. Both companies also are moving forward with advancing oral obesity drugs. 

Novo Nordisk is advancing an oral version of its obesity drug, Wegovy. Novo Nordisk already has an oral version of semaglutide, the active ingredient in Ozempic and Wegovy, on the market in Rybelsus, which was first approved in 2019, but that is indicated for treating Type 2 diabetes, not obesity. In May (May 2025), Novo announced that the US Food and Drug Administration (FDA) accepted its new drug application (NDA) submission for an investigational once-daily oral formulation of Wegovy (semaglutide) for chronic weight management in adults living with obesity or overweight with one or more comorbid conditions and to reduce the risk of major adverse cardiovascular events in adults with overweight or obesity and established cardiovascular disease. If approved, Wegovy would become the first oral formulation of a GLP-1 indicated for chronic weight management. The FDA action date to decide on the Wegovy oral formulation NDA is in the fourth quarter of 2025.

In addition, Novo Nordisk is advancing subcutaneous and oral amycretin into Phase III development in weight management based on completed clinical studies during the first quarter of 2025. Amycretin is a long-acting GLP-1 and amylin receptor agonist under development for treating adults with overweight or obesity and for Type 2 diabetes.

Novo Nordisk is also advancing CagriSema, a fixed-dose combination of a long-acting amylin analogue, cagrilintide, and semaglutide, the active ingredient in Wegovy and Ozempic. CagriSema is being investigated by Novo Nordisk as a once-weekly subcutaneous injectable treatment for adults with overweight or obesity (REDEFINE program) and as a treatment for adults with Type 2 diabetes (REIMAGINE program). To boost its obesity franchise further, its REDEFINE clinical trials have been initiated to investigate further the potential efficacy and safety of CagriSema. Also, semaglutide 7.2 mg (a higher dose of Wegovy) has been submitted to regulatory authorities in the European Union.

Longer term, Novo Nordisk is further building its pipeline of obesity drugs. In June (June 2025), Novo inked a deal worth up to $815 million with Deep Apple Therapeutics, a South San Francisco-based company specializing in small-molecule drug discovery to discover, develop, and commercialize oral small-molecule therapeutics directed at a non-incretin G protein-coupled receptors (GPCR) target for cardiometabolic diseases, including obesity, in a deal worth up to $812 million.

In May (May 2025), Novo Nordisk and Septerna, a San Francisco, California-based bio/pharmaceutical company focused on GCPRs, formed an exclusive global collaboration and license agreement to discover, develop, and commercialize oral small-molecule medicines for treating obesity, Type 2 diabetes, and other cardiometabolic diseases, in a deal worth up to $2.2 billion ($200 million upfront and near-term funding and $2 billion in milestone payments). The companies will initially commence four development programs for potential small-molecule therapies directed to one or more select GPCR targets, including GLP-1, GIP, and glucagon receptors. The companies will jointly conduct research activities from discovery through development candidate selection. Starting at investigational new investigational drug-enabling activities, Novo Nordisk will have sole responsibility for all global development and commercialization activities. In addition, Septerna has the right to opt in to a worldwide profit share for one program in the collaboration in lieu of future milestones and royalties for that product candidate.

Lilly is advancing Phase III trials for orforglipron, a once-daily small molecule (non-peptide) oral GLP-1 receptor agonist, for treating Type 2 diabetes and obesity. Orforglipron was discovered by Chugai Pharmaceutical and licensed by Lilly in 2018. Chugai and Lilly published the preclinical pharmacology data of this molecule together, and Lilly is running Phase III studies on orforglipron for the treatment of Type 2 diabetes and for weight management in adults with obesity or overweight with at least one weight-related medical problem. It is also being studied as a potential treatment for obstructive sleep apnea and hypertension in adults with obesity.

Roche is advancing an oral GLP-1 receptor agonist, CT-996, which it gained through its 2024 acquisition of Carmot Therapeutics, a Berkeley, California-based bio/pharmaceutical company, in a deal worth up to $3.1 billion ($2.7 billion at closing plus $400 million in potential milestone payments). The acquisition provided Roche with three clinical-stage assets with potential in treating obesity and diabetes. These included CT-996, a once-daily oral small-molecule GLP-1 receptor agonist, in Phase I, for treating obesity in patients with and without Type 2 diabetes, as well as two injectable clinical drug candidates: CT-388, a once-weekly subcutaneous injectable in Phase II, for treating obesity in patients with and without Type 2 diabetes, and CT-868, a once-daily subcutaneous injectable, in Phase II, for treating Type 1 diabetes patients with overweight or obesity.

In addition, earlier this year (2025), Roche made another move for an obesity drug by forming an exclusive collaboration and licensing agreement with Zealand Pharma, a Søborg, Denmark-based bio/pharmaceutical company, to co-develop and co-commercialize Zealand Pharma’s petrelintide. Under the deal, the two companies will co-develop and co-commercialize petrelintide and potential combination products, including petrelintide/CT-388, aiming to establish the amylin-based franchise for weight management and related indications. The companies will share profits and losses on a 50/50 basis for petrelintide and petrelintide/CT-388 in the US and Europe, and Zealand Pharma is eligible to receive royalties on net sales in the rest of the world. Total deal consideration amounts to $5.3 billion, including upfront cash payments of $1.65 billion and potential development milestone payments of $1.2 billion, primarily linked to initiation of Phase II trials with the petrelintide monotherapy .In April 2025, Zealand Pharma initiated Phase II trials with petrelintide in people with overweight or obesity and Type 2 diabetes, investigating the efficacy and safety of petrelintide over a treatment duration of 28 weeks.

Among smaller companies, Viking Therapeutics, a San Diego, California-based clinical-stage bio/pharmaceutical company, is advancing a dual GLP-1/GIP agonist, VK2735, for treating obesity for both subcutaneous and oral administration. The oral formulation is in Phase II development, and the subcutaneous formulation is planned for Phase III testing in 2025. In March (March 2025), Viking Therapeutics signed a multi-year contract with the CDMO CordenPharma to provide development and manufacturing services for clinical and commercial scale (drug substance and drug product) of VK2735 for both the subcutaneous and oral peptide formulations.