Pfizer's obesity effort centers on monthly GLP-1 berobenatide with 2028 approval target

Pfizer's obesity program now centers on berobenatide, an ultra-long-acting GLP-1 receptor agonist designed to be injected monthly, which the company says could become the first monthly GLP-1 peptide approved to treat obesity and related conditions ^[1]. Pfizer is targeting a first approval in 2028 ^[1].

The company described the drug's position on its second-quarter 2026 earnings call ^[1]. Berobenatide came with Pfizer's acquisition of obesity-focused startup Metsera, which followed a bidding war last year ^[1][2]. Pfizer said data presented at the American Diabetes Association Scientific Sessions reinforced its interest in the drug, and that it expects to advance 10 Phase 3 studies this year covering chronic weight management and obesity-related conditions ^[1]. In an Aug. 27 roundup of obesity catalysts, BioSpace described Pfizer as prioritizing its "ultra-long-acting" GLP-1, the drug that came out of the Metsera deal ^[2].

How much weight berobenatide helps people lose in late-stage testing, and how it compares with medicines already on the market, has not been reported. Pfizer has not released Phase 3 results, and its earnings call did not include detailed weight-loss figures from earlier studies of the drug ^[1]. The company has said only that it is targeting a first approval in 2028 ^[1].

The market Pfizer is entering is large and crowded. Obesity therapies recorded $66 billion in sales last year and could reach between $105 billion and $200 billion by 2027 and beyond, according to IQVIA figures cited by BioSpace ^[2]. Pfizer's call put the market at roughly $150 billion ^[1]; the two estimates differ. Eli Lilly leads sales with the injectable tirzepatide products Mounjaro and Zepbound and has launched the oral medicine Foundayo ^[2]. Novo Nordisk held about 90% of weekly prescriptions in the oral market with its Wegovy pill as of July, roughly 1.5 million people ^[2]. Analysts expect several companies to compete for third place behind those two ^[2].

Why it matters for patients

The leading GLP-1 injectables on the US market are taken weekly ^[2]. A monthly GLP-1 would mean far fewer injections per year for anyone who stays on it, but Pfizer has not said how such a product would be priced or how insurers would cover it ^[1]. It also has not been disclosed whether berobenatide would be tested in, or offered to, people already taking a weekly GLP-1 ^[1].

Access to obesity drugs is shifting on its own. The temporary Medicare GLP-1 Bridge program, which began in July 2026, is expected to grow coverage by an estimated 35% and give around 20 million potential patients in the program access to obesity medications, according to William Blair analysis cited by BioSpace ^[2].

For people weighing their current options, nothing changes yet. Berobenatide is investigational, its late-stage results are not public, and Pfizer's stated timeline puts a possible approval about two years away ^[1].

What happens next

• Pfizer expects to move 10 Phase 3 studies forward during 2026 and is targeting a first approval of berobenatide in 2028 ^[1].
• A regulatory decision on Novo Nordisk's CagriSema, a combination of cagrilintide and semaglutide, the active ingredient in Wegovy, is expected in the fourth quarter of 2026 ^[2].
• Lilly plans a regulatory submission for Foundayo in type 2 diabetes this year and for retatrutide in obesity and overweight in the early months of 2027 ^[2].
• AstraZeneca is expected to present data on its amylin candidate AZD6234 at the European Association for the Study of Diabetes meeting, held Sept. 28 to Oct. 2 in Italy ^[2].