Eli Lilly has invested heavily into obesity, dominating the landscape—alongside semaglutide maker Novo Nordisk—with its blockbuster molecule tirzepatide. Now, with a pipeline chock-full of numerous incretin therapies, the Big Pharma's new strategy will be to test some of those drugs across neurology and immunology indications.
"A new focus area first in 2025 will be to study potential new applications of incretin biology across diseases in neuroscience and immunology,” Lilly’s chief scientific officer Daniel Skovronsky, M.D., Ph.D., said during a Feb. 6 investor call. “With a pipeline of incretins in clinical development and deep scientific expertise in this space, Lilly is well positioned to match the biologic properties of specific molecules to the desired indications being studied.”
The pharma plans to launch several clinical trials “assessing potential benefits” of Lilly’s existing incretins across areas that “could include brain health, substance use disorder, pain, neuropsychiatry and inflammation,” Skovronsky explained.
“We'll be prepared to move rapidly into phase 3 trials based on clinical data and where our conviction is high,” the CSO added.
Lilly has invested billions into manufacturing capabilities to support the launch of obesity drug Zepbound and other phase 3 assets in cardiometabolic diseases, Patrik Jonsson, chief customer officer and president of diabetes and obesity, said last summer.
This massive investment and established infrastructure could now be used to support the company's potential expansion into other therapeutic landscapes.
The company did not elaborate further on what incretin drugs it plans to test.
A look at some of Lilly’s incretin therapies
Incretins are hormones that are released after eating, affecting the body’s insulin response.
Eli Lilly's approved incretin therapy is tirzepatide, an injectable dual GLP-1 and GIP receptor sold as Mounjaro for diabetes and Zepbound for weight loss and, most recently, obstructive sleep apnea. Tirzepatide is currently awaiting an FDA decision for use in heart failure preserved ejection fraction, as well.
The company also boasts the clinical-stage prospect retatrutide, a triple-hormone-receptor agonist that targets GLP-1, GIP and glucagon. In a phase 2 trial obesity trial, the investigational candidate was tied to a 24% mean reduction in weight, or the equivalent of 58 pounds, after 48 weeks.
After seeing the data, Lilly pressed the gas, entering retatrutide into a phase 3 program—dubbed TRIUMPH—that is testing the candidate out in chronic weight management, obstructive sleep apnea and knee osteoarthritis among people with obesity and who are overweight.
The pharma giant expects top-line readouts for both the obesity and osteoarthritis trials sometime this year, according to the company’s quarterly presentation Thursday. Lilly had previously said data were anticipated in early 2026.
“We believe this potential new medicine can deliver even more weight loss than tirzepatide and could potentially provide additional health benefits,” Skovronsky said on the investor call.
Furthermore, the company houses orforglipron, an investigational daily oral nonpeptide GLP-1 receptor agonist being tested in late-stage trials for obesity and obstructive sleep apnea. Lilly also plans to launch a phase 3 study for the candidate in hypertension this year.
“I’m excited that this year we're looking forward to reading out multiple orforglipron trials," Skovronsky said. "We expect to see data from up to five studies in Type 2 diabetes and two studies in obesity. Our goal is to generate [an] efficacy, safety and tolerability profile that is similar to that of an injectable, single-acting GLP-1, but through an orally available medicine.”