Eli Lilly Stockpiles $1.5B of Orforglipron Ahead of FDA Decision

Eli Lilly has assembled a stockpile of its oral weight loss drug orforglipron valued at $1.5 billion ahead of an anticipated FDA decision in April 2026, according to the company's 2025 annual report published in February 2026. The approval process has been expedited via receipt of a Commissioner's National Priority Review Voucher.

The substantial pre-launch inventory build represents an effort to avoid repeating the supply constraints that affected the rollouts of Mounjaro and Zepbound. In 2022, there were widespread shortages of tirzepatide products Zepbound and Mounjaro due to unprecedented demand. Many of the patients who struggled to find branded products turned to compounded alternatives, eroding revenue streams for Lilly. The shortages were resolved in late 2024.

Lilly announced positive topline results from the ATTAIN-MAINTAIN trial on December 18, 2025. The Phase 3 study evaluated orforglipron, an investigational, once-daily oral small molecule glucagon-like peptide-1 (GLP-1) receptor agonist, for weight maintenance over 52 weeks after initial treatment for 72 weeks with the highest tolerated doses of Wegovy (semaglutide) or Zepbound (tirzepatide), in participants from SURMOUNT-5 who were offered the opportunity to be re-randomized to receive orforglipron or placebo. At one year, orforglipron met the primary and all key secondary endpoints compared to placebo, delivering superior weight maintenance as an adjunct to a healthy diet and physical activity.

In pre-specified analyses at 52 weeks, participants who switched to orforglipron from Wegovy maintained their previously achieved weight loss with an average difference of 0.9 kg, while those who switched to orforglipron from Zepbound maintained their previously achieved weight loss with an average difference of 5.0 kg, using the efficacy estimand. In post-hoc analyses at 24 weeks, the last time point before placebo participants were eligible for orforglipron as rescue therapy, the change in body weight from ATTAIN-MAINTAIN baseline for patients switching to orforglipron from Wegovy was -0.1 kg vs. 9.4 kg for placebo. For patients switching to orforglipron from Zepbound, the change from baseline was 2.6 kg vs. 9.1 kg for placebo.

The overall safety and tolerability profile of orforglipron in ATTAIN-MAINTAIN was consistent with previous orforglipron Phase 3 studies. The most common adverse events were gastrointestinal-related and generally mild-to-moderate in severity. Discontinuation rates due to adverse events for patients randomized to placebo or orforglipron were 4.8% (orforglipron from Wegovy), 7.6% (placebo from Wegovy), 7.2% (orforglipron from Zepbound) and 6.3% (placebo from Zepbound). No hepatic safety signal was observed.

Lilly has submitted a new drug application to the U.S. Food and Drug Administration for orforglipron for the treatment of adults with obesity or overweight. Detailed results from the ATTAIN-MAINTAIN trial will be presented at a future medical meeting and published in a peer-reviewed journal next year.

Orforglipron is an investigational, once-daily small molecule (non-peptide) oral glucagon-like peptide-1 receptor agonist that can be taken any time of the day without restrictions on food and water intake. Orforglipron was discovered by Chugai Pharmaceutical Co., Ltd. and licensed by Lilly in 2018.

In February 2025, Lilly said it had already built up nearly $550 million worth of orforglipron-related inventory. Lilly is cementing a long-term strategy to maintain orforglipron production. Earlier in February 2026, Lilly announced the last of four new manufacturing facilities it plans to construct in the US as part of a $27 billion investment drive. At least three of these have been confirmed as production hubs for weight loss therapies such as orforglipron.

Novo Nordisk won US approval for the first oral GLP-1RA for weight loss in December 2025, with the pill, named oral Wegovy, launched in the US in January 2026. Novo Nordisk confirmed in its 2025 earnings call that there had been 50,000 prescriptions for the pill by the end of January.

Lilly recently reported a 45% surge in 2025 revenue, spearheaded by Zepbound and Mounjaro sales of $13.5 billion and $23 billion, respectively.