Insulin Icodec (Awiqli)

Insulin icodec is the first once-weekly basal insulin approved anywhere — a real engineering feat that turns a hormone the body normally clears within hours into one that lasts about a week. It's also a genuine case study in regulatory divergence: approved in Switzerland, Canada and the EU in 2024, rejected by the FDA that same year over manufacturing concerns and thin type 1 diabetes data, and only cleared in the US in March 2026 — for type 2 diabetes alone, after an FDA advisory committee voted against it for type 1.

A new way to make insulin last a week

Ordinary insulin, injected under the skin, is cleared from the body within hours — which is why basal (background) insulin has historically meant a daily injection. Insulin icodec (Awiqli, Novo Nordisk) reaches a once-weekly dosing interval through a chemistry trick with a close cousin already on this site: like somapacitan, this site's once-weekly growth hormone, it relies on reversible albumin binding rather than a slow-release prodrug or a fusion protein. Icodec's insulin molecule carries a 20-carbon fatty diacid side chain (icosanedioic acid) that binds tightly to circulating albumin, plus three amino acid substitutions (A14E, B16H, B25H) that both slow its enzymatic breakdown and reduce how strongly it binds the insulin receptor. The combined effect is a large, mostly inactive circulating depot bound to albumin that slowly and continuously releases small amounts of active insulin — stretching a hormone that would otherwise last hours into a measured human half-life of about 196 hours, roughly eight days.

The ONWARDS trials

Icodec's pivotal evidence comes from the ONWARDS program, a set of Phase 3a trials run head-to-head against existing daily basal insulins. In ONWARDS 1 (Rosenstock J, Bajaj HS, Janež A, et al., "Weekly Icodec versus Daily Glargine U100 in Type 2 Diabetes without Previous Insulin," N Engl J Med 2023;389(4):297-308, PMID 37356066, DOI 10.1056/NEJMoa2303208), 984 insulin-naive adults with type 2 diabetes were randomized 1:1 to once-weekly icodec or once-daily insulin glargine U100 over a 78-week trial (52-week main comparison). From a baseline HbA1c of 8.5%, icodec produced a superior reduction to glargine at week 52 (-1.55 vs -1.35 percentage points, estimated treatment difference -0.19, meeting the trial's superiority criterion). The broader ONWARDS program (four randomized, active-controlled trials cited in the FDA's approval, covering nearly 2,680 adults with type 2 diabetes) tested icodec against multiple daily comparators, in combination with mealtime insulin, oral agents and GLP-1 receptor agonists, and consistently found non-inferior or superior HbA1c control. A separate trial in the same program, ONWARDS 6, tested icodec in type 1 diabetes against daily insulin degludec — and found higher rates of level 2/3 hypoglycemia with icodec, a result that mattered for what happened next.

Approved everywhere else first, then a US rejection

Icodec's regulatory path ran through several other countries well before it reached American patients: Swissmedic approved it on 7 March 2024, Health Canada five days later on 12 March 2024, and the European Commission followed in May 2024 (after a positive CHMP opinion), with authorizations in Australia, Japan and China following. The FDA, reviewing an overlapping data package, instead issued a Complete Response Letter on 11 July 2024, citing unresolved manufacturing-process questions and a request for more clinical data specifically in type 1 diabetes — not a safety or efficacy finding against the type 2 diabetes evidence itself. Novo Nordisk resubmitted, and the FDA approved Awiqli (insulin icodec-abae) on 26 March 2026 — just under two years after patients in Switzerland, Canada and the EU already had access to it.

Why type 1 diabetes isn't on the US label

Unlike the type 2 diabetes indication, icodec's path into type 1 diabetes stalled specifically over safety, not manufacturing. On 24 May 2024, the FDA's Endocrinologic and Metabolic Drugs Advisory Committee voted 7-4 that icodec's benefits did not outweigh its risks for adults with type 1 diabetes, pointing to the higher hypoglycemia rates seen in ONWARDS 6 and the absence of a clear plan for helping patients manage risk across a week-long, front-loaded exposure curve (patients on icodec show a higher chance of hypoglycemia in the two to four days after each weekly dose, when circulating levels are highest). The FDA's eventual March 2026 approval covers only type 2 diabetes; no type 1 diabetes indication has been approved in the US as of this review, even though the drug carries a type 2-and-type 1 authorization in some other markets.

The boxed warning, and current status

Awiqli's FDA label carries a boxed warning for hypoglycemia due to medication errors and accidental overdose — specifically, serious hypoglycemia requiring hospitalization following mix-ups between Awiqli and other insulins or once-weekly injectable diabetes drugs, incorrect dose selection, or dosing more often than once weekly. That risk is a direct consequence of the same feature that makes the drug convenient: a once-weekly insulin sits alongside daily insulins and other once-weekly injectables (including GLP-1 drugs like semaglutide) in a way that creates a real mix-up hazard the label addresses directly, including an instruction never to draw icodec out of its pen with a syringe. Novo Nordisk made Awiqli available at more than 70,000 US pharmacies following approval, with a full nationwide launch planned for the second half of 2026; a competing once-weekly insulin from Eli Lilly, insulin efsitora alfa, had a positive EU committee opinion in June 2026 but remained without a final US or EU decision as of this review — worth checking against a current source rather than assuming either way.