Eli Lilly moves retatrutide obesity filing to early 2027
Lilly says two more late-stage trials support retatrutide, but manufacturing and quality-control data will push its obesity filing into 2027.
By Theo Nakamura · Staff Writer
· 3 min read
Eli Lilly now expects to seek regulatory approval for retatrutide, its experimental obesity injection, in the first quarter of 2027. For investors following the weight-loss drug market, the update adds stronger clinical data to Lilly’s case while delaying the filing timeline the company had previously suggested could arrive this year.
The company said Thursday that retatrutide met goals in two additional phase three trials, meaning late-stage studies generally used to support approval requests. Lilly said the weekly shot produced significant weight loss and improved a key measure of blood sugar in adults with obesity who also had either Type 2 diabetes or established cardiovascular disease.
Lilly told CNBC it needs more time to collect and verify manufacturing and quality-control information that regulators require before an application can be submitted. That pushes the expected filing for approval to the first quarter of 2027.
What the new trial data showed
In one phase three trial, Lilly said adults with obesity and Type 2 diabetes who received retatrutide lost up to an average of 20.8% of their body weight after 80 weeks. The company said that worked out to nearly 50 pounds on average for that group.
In a separate trial of adults with severe obesity and established cardiovascular disease, with or without diabetes, patients taking retatrutide lost up to an average of 22.6% of body weight after 80 weeks, according to Lilly. The company said that equaled 55.8 pounds on average.
Lilly also said retatrutide reduced certain cardiovascular risk factors in that second group. The company did not say Thursday that the drug has been approved, and regulators will still need to review the full application once Lilly files it.
Kenneth Custer, president of Lilly Cardiometabolic Health, said in a company release that Lilly believes the data package can support global filings for retatrutide as a potential treatment for obesity, knee osteoarthritis pain and obstructive sleep apnea.
Why retatrutide is different
Retatrutide is often described as a “triple G” drug because it targets three hormone pathways: GLP-1, GIP and glucagon. Those are hormone signals involved in appetite, satisfaction with food and metabolic function. Existing obesity drugs generally target one or two of those pathways.
Lilly’s Zepbound uses tirzepatide, which mimics GLP-1 and GIP. Novo Nordisk’s Wegovy uses semaglutide, which mimics GLP-1. Lilly has positioned retatrutide as another major part of its obesity portfolio after Zepbound and its newly launched pill, Foundayo.
The company said side effects in the two new trials were consistent with earlier retatrutide studies. The most common side effects included diarrhea, nausea and constipation, which Lilly said are also seen across the broader GLP-1 class.
Retatrutide has now reported positive results in five late-stage trials, according to Lilly. TD Cowen analysts estimated in a January note that the drug could generate $3.8 billion in sales in 2030. Some analysts estimate the wider weight-loss and diabetes drug market could reach about $100 billion by the 2030s.
This story draws on original reporting from CNBC.
