A patient-friendly guide by RealMedVision.
Medically reviewed | 10 to 12 min read
A once-weekly insulin for type 2 diabetes has completed Phase 3 trials and received a positive EU recommendation, with approval still pending.
For anyone tired of a daily injection, the idea of just one jab a week is a real change worth understanding properly.
Insulin efsitora alfa is a new kind of insulin taken just once a week. Its brand name is Onswik, and it is made by Eli Lilly. For people with type 2 diabetes who need insulin, it offers something simple: one injection a week instead of one every day.
This medicine is a basal insulin, the background insulin that keeps blood sugar steady between meals and overnight. Most basal insulins are injected daily. Insulin efsitora alfa is designed to last a full week from one dose.
As of August 2026, the medicine has a positive opinion from the European Union’s medicines regulator but is not yet fully approved there, and it is not available in India. The details here come from large clinical trials and official regulatory reviews, not from marketing. Always follow what your own doctor tells you.
2026 update: On 25 June 2026, the European Medicines Agency’s expert committee (CHMP) adopted a positive opinion recommending Onswik for approval in adults with type 2 diabetes. Final authorisation by the European Commission is a separate step and was still awaited as of August 2026. Regulatory status differs by country, and the medicine is also under review in other markets.
Quick answer
- What it is: a once-weekly basal (background) insulin studied mainly for type 2 diabetes.
- Names: brand name Onswik, medicine name insulin efsitora alfa, maker Eli Lilly.
- How it is taken: one injection under the skin, once every week.
- Main benefit: far fewer injections than daily insulin.
- Main risk: low blood sugar, the same core risk as any insulin.
- India status: not yet approved or sold in India as of 2026.
What is insulin efsitora alfa?
The medicine is a laboratory-made insulin analogue. An analogue means the natural insulin molecule has been slightly changed to behave in a useful new way. Here, the change lets a single dose keep working for about seven days. It is injected just under the skin, which doctors call the subcutaneous route.
Eli Lilly developed it under the code name LY3209590 before it received its official name. In the European Union, the medicine is being evaluated under the brand name Onswik, and in June 2026 the CHMP recommended it for approval in adults with type 2 diabetes. It sits in the same family as daily background insulins such as glargine and degludec, which many people with diabetes in India already use.
For your target sugar control, see [HbA1c normal range].
How insulin efsitora alfa works
It helps to know what insulin does. Insulin is a hormone that moves sugar out of the blood and into the body’s cells for energy. In type 2 diabetes, the body either makes too little insulin or does not use it well, so sugar builds up in the blood.
The weekly design, in plain terms
Ordinary basal insulins clear within a day, so they need a daily injection. Insulin efsitora alfa is joined to a large protein piece called an Fc domain, borrowed from the body’s own antibodies. This attachment protects the insulin and slows how fast the body breaks it down. The result is a slow, steady release that lasts roughly a week from one dose.
Why a steady level matters
A good basal insulin gives a smooth, flat level without sharp peaks, which can push blood sugar too low. Eli Lilly says it was built with a low peak-to-trough ratio, meaning the level stays fairly even across the week. In simple words, it aims to avoid big ups and downs.
See [Blood sugar chart by age]
Good to know: once-weekly does not mean stronger. The goal is to give the background insulin effect across the whole week, instead of a separate basal injection every day.
What the QWINT trials found
The QWINT programme tested insulin efsitora alfa in more than 3,000 people with type 2 diabetes across several countries. Each trial aimed to show the weekly insulin controlled blood sugar at least as well as a standard daily insulin. This is measured by HbA1c, a blood test showing average blood sugar over about three months.
Across the type 2 diabetes trials, the weekly insulin was non-inferior, meaning it worked about as well as daily insulin, not worse. The table shows each trial’s main published result, using the treatment-regimen analysis at its primary timepoint (week 52 for QWINT-1 and QWINT-2, week 26 for the others). Because the trials studied different patients over different lengths, the figures are not meant to rank one trial against another. Your own response could be higher or lower, because every person is different.
| Trial | Population | Compared with | HbA1c reduction | Low blood sugar (events per patient-year) |
|---|---|---|---|---|
| QWINT-1 | Type 2, new to insulin | Daily glargine | 1.19% vs 1.16% | 0.50 vs 0.88 (lower with efsitora) |
| QWINT-2 | Type 2, new to insulin | Daily degludec | 1.26% vs 1.17% | 0.58 vs 0.45 (no severe cases with efsitora) |
| QWINT-3 | Type 2, already on insulin | Daily degludec | 0.81% vs 0.72% | 0.84 vs 0.74 (similar) |
| QWINT-4 | Type 2, on basal and mealtime insulin | Daily glargine U100 | 1.01% vs 1.00% | 6.6 vs 5.9 (both also on mealtime insulin) |
| QWINT-5 | Type 1 diabetes | Daily degludec | 0.51% vs 0.56% | Higher with efsitora (14.03 vs 11.59, severe in 10% vs 3%) |
The type 2 diabetes results were the basis for the regulatory applications. Summing up those trials, the European medicines regulator judged the difference in HbA1c between efsitora and daily insulin to be very small, at most around 0.09%. The type 1 result, from QWINT-5, is an important caution. In that trial, severe low blood sugar affected 10% of people on efsitora versus 3% on the daily insulin, so a weekly schedule may not suit everyone with type 1 diabetes. A 2026 pooled analysis of six trials found control and safety broadly comparable to daily basal insulins in type 2 diabetes.
Onswik dosage and how it is given
One point matters most here. This article cannot tell you your dose. Insulin doses are worked out for each person by a doctor, based on weight, blood sugar readings, other medicines, and how the body responds. What follows is general information only.
Dose forms and strengths
In its European filing, Onswik is a solution for injection in a pre-filled pen, in two strengths, 500 units per millilitre and 1000 units per millilitre. The higher strength lets a full weekly dose fit a small injection volume. The pen injects under the skin, usually in the stomach, thigh, or upper arm.
Starting and adjusting the dose
In the trials, people began on a set weekly dose and moved up in fixed steps until blood sugar reached target. A doctor guides this titration, which means slowly finding the right dose. Missing a weekly dose, or taking it twice, can push blood sugar too high or too low, so a reminder helps.
See how the rival weekly insulin is dosed in [Awiqli dosage and Price]
Patient tip: if a weekly insulin is ever prescribed for you, pick a fixed day and set a phone reminder. Consistency helps keep your level steady and lowers the chance of a mistake.
Side effects of insulin efsitora alfa
Like every insulin, the most important side effect is hypoglycaemia, or low blood sugar. It happens when insulin lowers sugar more than the body needs at that moment. In the type 2 diabetes trials, low blood sugar rates were broadly similar to daily insulins, and in one trial lower. Still, the risk is never zero, and is highest when a dose is missed, meals are skipped, or during heavy exercise.
Common and expected effects
Beyond low blood sugar, insulins can cause mild reactions where the injection is given, such as redness or a small lump. Some people notice slight weight change as control improves. In the trials, overall side effect rates were similar for weekly and daily insulin.
See [Type 2 diabetes in young Indians]
Serious effects and when to seek help
Severe low blood sugar is a medical emergency. The table lists the warning signs so a patient or family member can act quickly. Knowing mild from severe signs can prevent a dangerous situation.
| Mild low blood sugar | Severe low blood sugar (emergency) |
|---|---|
| Shaking, sweating, or feeling cold | Confusion or slurred speech |
| Sudden hunger | Unable to eat or drink safely |
| Fast heartbeat or dizziness | A fit or seizure |
| Feeling anxious or irritable | Drowsiness or fainting |
For mild signs, the usual advice is to take fast-acting sugar at once, such as glucose tablets, a sugary drink, or juice, then recheck. Severe signs need urgent help, covered below.
Who should be careful: cautions and interactions
Any insulin must be used carefully alongside other medicines and conditions. Because efsitora has a long duration of action, low blood sugar needs careful monitoring and dose management, and a single dose stays active for a week.
Tell your doctor about all other diabetes medicines, since combining insulin with certain tablets or injections can raise the chance of low blood sugar. Kidney or liver problems, and illnesses that change appetite, also affect insulin needs. In pregnancy and breastfeeding, insulin needs change a great deal and must be managed by a specialist, and this medicine has not been studied enough in pregnancy to guide use here. Its use in children has not been established, so it is not covered.
When to call your doctor: tell your doctor promptly if you have repeated low sugar episodes, an infection or illness that stops you eating, or if you are pregnant or planning a pregnancy. Your insulin plan may need to change.
Onswik compared with Awiqli and daily insulin
It is not the first once-weekly insulin. A rival, Awiqli from Novo Nordisk, uses a different molecule called insulin icodec. The table sets the three options side by side.
For a closer look, see [Awiqli vs daily insulin comparison].
| Feature | Onswik (insulin efsitora alfa) | Awiqli (insulin icodec) | Daily basal insulin |
|---|---|---|---|
| Injection schedule | Once a week | Once a week | Once a day |
| Type | Weekly basal insulin (Fc-based) | Weekly basal insulin | Daily basal insulin, such as glargine or degludec |
| Company | Eli Lilly | Novo Nordisk | Several makers |
| Approval stage | Positive EU CHMP opinion, authorisation pending | Approved in several countries | Approved and used for many years |
| Main appeal | Fewer injections | Fewer injections | Long, well-known track record |
Is insulin efsitora alfa available in India?
Not yet. As of August 2026, insulin efsitora alfa has not been approved or launched in India. It has a positive opinion in the European Union and is under review in other regions, and Eli Lilly has said it planned to submit the medicine to health authorities worldwide. Whether it reaches India will depend on approval by the Indian drug regulator, which runs its own review.
Because it is not on sale in India, there is no official Indian price. Any figure seen online today is a guess. This guide will be updated when there is real news on Indian approval and pricing. For now, people who want a once-weekly option can ask their doctor what is available.
See also [Semaglutide brands in India].
Warning signs that need urgent care
A sudden severe drop in blood sugar is the main emergency linked to any insulin. If a person becomes very drowsy, confused, cannot swallow safely, faints, or has a fit, treat it as an emergency. Do not give food or drink to someone who is not fully awake, because it can enter the lungs.
Call emergency services straight away. In India, the numbers are 112 or 108. If a glucagon injection has been prescribed and a family member is trained to give it, it can be used while waiting. Once the person is awake and can swallow, fast-acting sugar and a snack help prevent another drop. Very high blood sugar with vomiting, deep breathing, or drowsiness also needs urgent care.
Keep in mind: because efsitora has a long duration of action, low blood sugar needs careful monitoring and dose management. Stay in touch with your care team after any severe episode.
A quick example (illustrative only): Meera, 54, has had type 2 diabetes for eight years. Her tablets no longer control her sugar, and her doctor suggests insulin, but she dreads a daily jab. A once-weekly option would mean one injection on a fixed day, far easier to fit into her week. Meera is not a real patient. The example only shows who such a medicine may suit, and any decision to start insulin is made with a doctor.
Key takeaways
- Onswik (insulin efsitora alfa) cuts basal insulin from a daily to a weekly injection for type 2 diabetes.
- In the QWINT trials it lowered HbA1c about as well as leading daily insulins.
- Low blood sugar stays the main risk. Learn the warning signs and keep fast-acting sugar within reach.
- It has a positive CHMP opinion in the EU, but final marketing authorisation is still pending, and it is not yet available or priced in India.
- In type 1 diabetes, trial data showed more serious low sugar, so a weekly schedule is not right for everyone.
- Never start, stop, or change any insulin on your own. That decision belongs with your treating doctor.
Frequently asked questions
What is insulin efsitora alfa?
Developed by Eli Lilly, insulin efsitora alfa is a once-weekly background insulin. A single injection is designed to control blood sugar for about seven days, replacing the daily basal injection many patients take.
What is Onswik?
Onswik is the brand name for insulin efsitora alfa in the European Union, where the regulator’s committee recommended it for approval in June 2026. The medicine inside is the same. A brand name simply sits over the generic drug name.
Is insulin efsitora alfa available in India?
No. As of August 2026 it is not approved or launched in India. It has a positive opinion in the European Union, but Indian availability would first need clearance from the Indian drug regulator.
How is a once-weekly insulin different from daily insulin?
The main difference is frequency. Daily basal insulin clears within a day. A weekly insulin releases slowly over seven days, so one injection covers the whole week.
Does insulin efsitora alfa cause weight gain?
Some weight change can happen with any insulin as control improves. In the trials, weight effects were broadly similar to daily basal insulin. Your doctor can advise on managing weight during treatment.
Is efsitora alfa the same as Awiqli?
They are not the same. Both are once-weekly insulins, but Awiqli uses insulin icodec from Novo Nordisk, while efsitora alfa is a different molecule from Eli Lilly. They are rivals in the same class.
Can it be used for type 1 diabetes?
It was tested in type 1 diabetes, but serious low blood sugar occurred more often than with daily insulin. A weekly schedule may not suit type 1 diabetes, and any use would need close specialist supervision.
What are the main side effects?
Low blood sugar is the most important one, as with all insulins. Milder effects include injection-site reactions and small weight changes. The warning signs of low blood sugar are listed earlier.
How much will insulin efsitora alfa cost in India?
There is no confirmed Indian price yet, because it is not on sale in India. Any cost quoted online today is guesswork. A real price will only emerge if and when it is approved and launched here.
Can I switch from my daily insulin to a weekly one?
Switching insulin is never a do-it-yourself change. Even when a weekly insulin is available, only your doctor can decide if it suits you and how to move across safely.
Medical disclaimer:
This article is for general education only. It does not replace advice from a qualified doctor or pharmacist. Insulin efsitora alfa is not yet approved in India, and the details here come from clinical trials and regulatory reviews. Never begin, stop, or change any insulin without guidance from your treating doctor.
About the author:
Iraphan Khan, BSN, RN, D.Pharm is the founder of RealMedVision and a Public Health Researcher who creates evidence-based health content from trusted medical sources.
Medically reviewed by:
This guide was checked for medical accuracy by our review board before publishing.
Dr. Praveen Verma, MBBS, MD (Pathology), Pathologist and Clinical Laboratory Specialist.
Dr. Himanshu Morya, MBBS, Medical Educator.
References
- European Medicines Agency, Onswik (insulin efsitora alfa) medicine overview, 2026.
- New England Journal of Medicine, insulin efsitora versus degludec in type 2 diabetes without previous insulin (QWINT-2), 2024.
- The Lancet, once-weekly efsitora versus degludec in type 2 diabetes on basal insulin (QWINT-3), 2025.
- The Lancet, once-weekly efsitora versus glargine U100 in type 2 diabetes on basal and prandial insulin (QWINT-4), 2025.
- Eli Lilly, detailed QWINT-1, QWINT-3 and QWINT-4 Phase 3 results, 2025.
- Eli Lilly, QWINT-5 results in type 1 diabetes, 2024.
- Frontiers in Endocrinology, meta-analysis of insulin efsitora in type 2 diabetes, 2026.
- Medscape, insulin efsitora alfa drug monograph, pending FDA approval, 2026.
- Eli Lilly, clinical development pipeline entry for LY3209590 (insulin efsitora alfa).