The Food and Drug Administration approved Onswik, Eli Lilly's once-weekly basal insulin, for adults with type 2 diabetes on September 24, 2026, Healio ↗ reported. The drug, generic name insulin efsitora alfa, is designed to be injected once a week instead of once a day. That drops the count from roughly 365 shots a year to about 52, a reduction Lilly puts at more than 300 injections annually.
Efsitora is an engineered insulin built to linger in the bloodstream for a full seven days and release steadily, so a single weekly dose covers the background insulin that people with type 2 diabetes gradually lose the ability to make on their own. It binds the same insulin receptor ↗ that daily basal insulins target. The change is in how long one molecule stays active, not in what it does once it gets there.
The approval rests on QWINT, a program of four phase-3 trials that together enrolled more than 3,400 adults with type 2 diabetes. The headline result across those trials is worth reading carefully: efsitora matched daily insulin on blood-sugar control, it did not beat it. In QWINT-3, published in The Lancet ↗01044-X), insulin-experienced patients on weekly efsitora saw their average A1c (a three-month blood-sugar measure where lower is better) fall by 0.86 percentage points versus 0.75 for daily degludec, landing at 6.93 percent and 7.03 percent. Those endpoints are statistically non-inferior, which means the weekly shot is as good as the daily one, not better.
The more interesting signal is on hypoglycemia, the dangerous low-blood-sugar episodes that make insulin hard to dose. In QWINT-1, published in the New England Journal of Medicine ↗, insulin-naive patients starting weekly efsitora had fewer of those events than patients on daily glargine, 0.50 versus 0.88 events per person per year, a rate ratio of 0.57 that works out to roughly 43 percent fewer. A companion trial in The Lancet ↗01069-4) tested efsitora on top of mealtime insulin, a harder regimen to control, and it held up there too.
Two cautions sit alongside the win. Onswik is approved only for type 2 diabetes, not type 1, where the trials flagged a higher risk of severe lows. And because a week of insulin is packed into one injection, the drug ships in high-concentration KwikPens (U-500 and U-1,000) that deliver far more units per shot than standard pens, which changes how carefully a dose has to be set and checked.
Onswik is the second once-weekly insulin the FDA has cleared, following Novo Nordisk's insulin icodec (Awiqli) earlier in 2026. Lilly says US availability is coming in the following months. The drug is already approved in the European Union, Mexico, and Japan.
The case for a weekly basal insulin was never about tighter numbers. It is about whether cutting 300 injections a year gets more people to start insulin, and to stay on it, without giving up control. The QWINT data say the trade is roughly even on glucose and favorable on lows. Whether that shifts real-world uptake is the question the trials could not answer.