FDA Approves Lilly's Insulin Efsitora Alfa-Gobe (Onswik) for Type 2 Diabetes

FDA has approved insulin efsitora alfa-gobe (Onswik), Eli Lilly and Company's (Lilly’s) once-weekly basal insulin, on September 24, 2026, as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes.¹ The approval is based on the QWINT phase 3 clinical trial program, which enrolled more than 3400 adults with type 2 diabetes across 4 global registration studies.¹

"For over a century, Lilly has been developing insulins that transformed diabetes care for millions of people worldwide, but delays in initiating treatment and the burden of daily injections can have a real impact on patients' day-to-day experience managing type 2 diabetes," said Kenneth Custer, PhD, executive vice president and president, Lilly Cardiometabolic Health, in a company press release.¹ "Onswik offers a new once-weekly basal insulin option for patients and reflects our continued commitment to deliver innovative treatment options that expand choice and provide greater flexibility in how people manage type 2 diabetes."

What is Onswik and how does it work?

Onswik is designed to deliver steady basal insulin levels over a full seven days and is intended to reduce injections by more than 300 per year compared with a once-daily basal insulin, roughly 52 injections annually versus 365.¹ The Onswik KwikPen will be available in the United States in the coming months in 2 concentrations: a 500 units/mL pen containing 1500 units total and a 1000 units/mL pen containing 3000 units total.

What clinical evidence supports the approval?

Across the QWINT trials, once-weekly efsitora met its primary endpoint of non-inferior A1C reduction from baseline compared with insulin glargine U-100 or insulin degludec U-100. QWINT-1 (NCT05662332) randomized 795 insulin-naive adults to efsitora or glargine over 52 weeks,¹^,² while QWINT-3 randomized 986 adults already on basal insulin to efsitora or degludec, meeting its primary A1C endpoint at week 26.¹^,³ QWINT-2 randomized 928 insulin-naive adults to efsitora or degludec and also assessed outcomes in patients using and not using glucagon-like peptide-1 receptor agonists.¹ QWINT-4 randomized 730 adults already using basal and mealtime insulin to efsitora or glargine, both given alongside mealtime insulin lispro, with non-inferior A1C reduction at week 26.¹

What are the safety considerations?

Onswik demonstrated an overall safety profile similar to the daily basal insulins studied in the QWINT trials.¹ Lilly stated that It should not be used by people with type 1 diabetes because of an increased risk of severe hypoglycemia.¹ Common side effects include low blood sugar, allergic reactions, injection-site reactions, lipodystrophy, itching, rash, swelling of the hands and feet, and weight gain.¹

How does this fit into Lilly's broader diabetes portfolio?

This is the fourth global approval for Onswik, following clearances from the European Medicines Agency, Mexico's Comisión Federal para la Protección contra Riesgos Sanitarios, and Japan's Pharmaceuticals and Medical Devices Agency.¹ This new FDA approval expands Lilly's type 2 diabetes portfolio, which already includes other insulins, incretins, and oral and injectable medications.¹ Roughly 1 in 8 Americans live with diabetes, most with type 2 disease, and Lilly cited projections that more than 510 million people worldwide will have diabetes by 2030, with 38 million expected to use insulin.¹

What are the limitations?

The injection-reduction estimate compares approximate annual injection counts rather than a formal outcomes measure, and the QWINT trials compared efsitora only with glargine and degludec, not with newer non-insulin therapies. Long-term, real-world safety and adherence data beyond the trial program are not yet available, and the QWINT trials were sponsored by Lilly.

References

1. Eli Lilly and Company. US Food and Drug Administration (FDA) approves Lilly's Onswik (insulin efsitora alfa-gobe), a once-weekly basal insulin injection treatment for adults living with type 2 diabetes. Press release. Published September 24, 2026. Accessed September 28, 2026. https://investor.lilly.com/news-releases/news-release-details/us-food-and-drug-administration-fda-approves-lillys-onswiktm
2. A Study of insulin efsitora alfa (LY3209590) compared to glargine in adult participants with type 2 diabetes who are starting basal insulin for the first time (QWINT-1) (QWINT-1). ClinicalTrials.gov; NCT05662332. Updated August 6, 2024. Accessed September 28, 2026. https://clinicaltrials.gov/study/NCT05662332
3. Philis-Tsimikas A, Bergenstal RM, Bailey TS, et al. Once-weekly insulin efsitora alfa versus once-daily insulin degludec in adults with type 2 diabetes currently treated with basal insulin (QWINT-3): a phase 3, randomized, non-inferiority trial. Lancet. 2025;405(10497):2279-2289. doi:10.1016/S0140-6736(25)01044-X