Onswik

Onswik is a long-acting, once-weekly insulin used to control high blood sugar in adults with type 2 diabetes mellitus alongside diet and exercise. Onswik is given as an injection under the skin (subcutaneous) once a week, on the same day each week. Onswik is not recommended for people with type 1 diabetes because of an increased risk of severe low blood sugar (hypoglycemia). It is not known if Onswik is safe and effective in children.

Onswik is a basal insulin. It works in the background throughout the day and night to keep blood sugar steady between meals. It may be used alone or together with oral or injectable diabetes medicines, including mealtime (rapid-acting or short-acting) insulin.

Onswik (insulin efsitora alfa-gobe) was approved by the FDA on September 24, 2026. It is the second once-weekly insulin approved for adults with type 2 diabetes. Approval was based on four QWINT trials that enrolled 3,439 adults with type 2 diabetes. These trials compared once-weekly Onswik with a once-daily basal insulin (insulin glargine or insulin degludec). The trials included people who had never used insulin before and people who were switching from daily basal insulin, with or without mealtime insulin.

• Blood sugar control was measured with HbA1c, which reflects average blood sugar over the past 2 to 3 months. In all four trials, Onswik lowered HbA1c by about the same amount as daily insulin (it met the non-inferiority margin).

*QWINT-3 lasted 78 weeks overall. The main result was measured at week 26.

Do not use Onswik:

• during an episode of low blood sugar (hypoglycemia).
• if you are allergic to insulin efsitora alfa-gobe, or any of the ingredients in Onswik.

Before taking Onswik, tell your healthcare provider about all of your medical conditions, including if you:

• have type 1 diabetes. Onswik is not recommended for people with type 1 diabetes. In a clinical trial in adults with type 1 diabetes, severe low blood sugar happened more often with Onswik than with insulin degludec (10% vs 3%)
• have liver or kidney problems
• have heart failure or other heart problems
• take a TZD medicine, such as pioglitazone or rosiglitazone
• are pregnant or plan to become pregnant. Use of Onswik during pregnancy is not recommended. Talk to your healthcare provider about the best way to control your blood sugar if you plan to become pregnant or become pregnant while using Onswik
• are breastfeeding or plan to breastfeed. Use of Onswik while breastfeeding is not recommended. Talk to your healthcare provider about the best way to feed your baby.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Onswik may cause serious side effects, including:

• Low blood sugar (hypoglycemia). Severe low blood sugar can cause seizures or loss of consciousness, and can be life-threatening or cause death. Onswik works for a long time, so recovery from low blood sugar may take longer than with shorter-acting insulins. Serious low blood sugar needing hospital care has happened when once-weekly insulin was mixed up with another insulin or diabetes medicine, or when the wrong dose was dialed or given too often. Signs and symptoms of low blood sugar may include: dizziness or light-headedness blurred vision sweating hunger shakiness confusion fast heartbeat headache.
• Severe allergic reactions. Get medical help right away if you have a rash over your whole body, trouble breathing, or other signs of a serious allergic reaction.
• Low potassium in your blood (hypokalemia).
• Heart failure. Taking certain diabetes pills called thiazolidinediones (TZDs) with insulin, including Onswik, can cause fluid retention and may lead to or worsen heart failure. Tell your healthcare provider if you have new or worse shortness of breath, swelling of your ankles or feet, or sudden weight gain.

Your insulin dose may need to be changed because of: a change in level of physical activity or exercise, weight gain or loss, increased stress, change in diet, illness, or other medicines you take.

Get emergency medical help if you have: trouble breathing, shortness of breath, fast heartbeat, swelling of your face, tongue, or throat, sweating, extreme drowsiness, dizziness, or confusion.

Common side effects

The most common side effects of Onswik include:

• low blood sugar (hypoglycemia)
• allergic reactions
• reactions at the injection site
• skin thickening or pits at the injection site (lipodystrophy)
• itching
• rash
• swelling of your hands and feet
• weight gain.

These are not all of the possible side effects of Onswik. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Onswik (insulin efsitora alfa-gobe) is a long-acting insulin analog. It is made of a single-chain insulin joined to part of a human antibody (an IgG2 Fc region). Like other insulins, it lowers blood sugar by helping muscle and fat take up glucose from the blood and by reducing how much glucose the liver makes.

Onswik lasts much longer than daily basal insulins because:

• Its large size means the kidneys clear it more slowly.
• Its binding to the neonatal Fc receptor protects it from being broken down.
• It also binds the insulin receptor less strongly than human insulin, which slows its removal.

The half-life of Onswik is about 17 days. Its glucose-lowering effect covers the full week between doses and can last about 4 to 6 weeks after the last injection.

• Your healthcare provider or diabetes educator will show you and your caregiver how to select and inject your weekly dose before you start. Read the Instructions for Use that come with your pen.
• Inject Onswik under the skin once a week, on the same day each week. You can change your injection day if at least 4 days have passed since your last dose. Then keep using the new day each week.
• Your first dose may be a larger, one-time starting dose. Do not repeat the one-time starting dose.
• Always check the pen label before each injection to make sure you are using Onswik and not another insulin or diabetes medicine.
• Onswik is dosed differently from other insulins and diabetes medicines. Always check the dialed units in the dose window before each injection. Do not dial the maximum dose (400 units on the U-500 pen or 800 units on the U-1,000 pen) unless this is your prescribed dose.
• Do not use a syringe to remove Onswik from the pen. The syringe markings will not measure the dose correctly, and this can cause an overdose and severe low blood sugar.
• Inject into your stomach area (abdomen), buttocks, thigh, or upper arm. Change (rotate) the injection site within the same area each week. Do not inject into skin that is thickened, pitted, or lumpy.
• Use a new needle for each injection. Never share your Onswik pen with another person, even if the needle is changed. Sharing can spread serious infections.
• Do not inject Onswik into a vein or muscle, and do not use it in an insulin pump. Do not mix Onswik with any other insulin or liquid.
• Check your blood sugar as your healthcare provider tells you. It takes 1 to 2 weeks to see the first changes in fasting blood sugar after a dose change, and about 4 weeks for the full effect. Do not change your dose without talking to your healthcare provider.

If you miss a dose of Onswik:

• if it has been 4 days or less, take the missed dose as soon as possible, then go back to your usual weekly day.
• if it has been more than 4 days, either skip the missed dose and take your next dose on your usual day, or take the missed dose and then take Onswik once a week from that day.
• check your blood sugar more often.

If you take more than one dose in the same week, or take the one-time starting dose more than once, skip the next week's dose and check your blood sugar more often.

• Store Onswik pens in the refrigerator between 36°F and 46°F (2°C and 8°C), both before and after first use.
• If a refrigerator is not available, the pen can be kept at room temperature up to 86°F (30°C) for a total of 14 days. Throw the pen away if it has been out of the refrigerator for more than 14 days in total.
• Throw the pen away 112 days (16 weeks) after first use, even if there is insulin left in it.
• Do not freeze Onswik, and do not use it if it has been frozen. Keep it away from heat and light.
• Do not store the pen with the needle attached.

Many medicines can raise or lower blood sugar, or change how well Onswik works.

• These include other diabetes medicines, steroids, and some blood pressure medicines.
• Beta-blockers, clonidine, guanethidine, and reserpine can hide the warning signs of low blood sugar.
• Medicines called neonatal Fc receptor (FcRn) inhibitors, such as efgartigimod, rozanolixizumab, and nipocalimab, may make Onswik work less well.

Your healthcare provider may switch you to a different basal insulin if you need one of these. Keep a list of your medicines to show your healthcare provider and pharmacist when you get a new medicine.

Active ingredients: insulin efsitora alfa-gobe

Inactive ingredients: benzyl alcohol, dibasic sodium phosphate, glycerin, monobasic sodium phosphate, phenol, poloxamer 188, and Water for Injection. Hydrochloric acid, glacial acetic acid and/or sodium hydroxide may be added to adjust the pH.

Manufactured by Eli Lilly and Company, Indianapolis, IN 46285, USA. US License No. 1891. For more information, go to www.onswik.lilly.com or call 1-800-LillyRx (1-800-545-5979).