Onswik Is Second Weekly Insulin Approved for Type 2 Diabetes

The FDA has approved insulin efsitora alfa-gobe (Onswik, Eli Lilly), a once-weekly long-acting insulin analog, as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus (T2DM). According to the agency, Onswik is the second once-weekly insulin approved for adults with T2DM.

Efsitora is administered by subcutaneous injection once weekly on the same day each week. The FDA said it is not recommended for patients with type 1 diabetes because of an increased risk of severe hypoglycemia. According to Lilly, the Onswik KwikPen will be available in the US in the coming months in 2 concentrations: 500 units/mL (1,500 units total) and 1,000 units/mL (3,000 units total).

The approval was based on the phase 3 QWINT program, which comprised 4 randomized, open-label, active-controlled trials that enrolled more than 3,400 adults with T2DM. Participants included insulin-naive adults (QWINT-1 and QWINT-2), adults previously treated with basal insulin (QWINT-3), and adults treated with basal and mealtime insulin (QWINT-4). Once-weekly efsitora was compared with once-daily insulin glargine U-100 or insulin degludec U-100. The FDA reported that efsitora reduced hemoglobin A1c (HbA1c) to a similar extent as the comparators, and Lilly said each trial met its primary endpoint of noninferior HbA1c reduction from baseline, assessed at week 52 in QWINT-1 and QWINT-2 and at week 26 in QWINT-3 and QWINT-4.

The most common adverse reactions include hypoglycemia, hypersensitivity reactions, injection site reactions, lipodystrophy, pruritus, rash, edema, and weight gain, according to the FDA. Labeling includes warnings and precautions for medication errors and accidental overdose, hypersensitivity reactions, hypokalemia, and fluid retention and heart failure with certain medications; Lilly's safety summary identifies thiazolidinediones in that context. Lilly said efsitora's overall safety profile in the trials was similar to that of the daily basal insulins studied.

Lilly said the US decision is the fourth global approval of efsitora for adults with T2DM, following actions by the European Medicines Agency, Mexico's Federal Commission for the Protection against Sanitary Risks, and Japan's Pharmaceuticals and Medical Devices Agency. The company noted that safety and effectiveness in children have not been established.

Sources: US Food and Drug Administration. FDA approves once-weekly insulin for type 2 diabetes mellitus. US Food and Drug Administration; September 24, 2026. Accessed September 25, 2026.

Eli Lilly and Company. U.S. 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. Eli Lilly and Company; September 24, 2026. Accessed September 25, 2026.

Onswik (insulin efsitora alfa-gobe) injection, for subcutaneous use. Prescribing information. Lilly USA, LLC; 2026. Accessed September 25, 2026.