Diabetes Distilled: Insulin efsitora alfa set to change basal insulin use in type 2 diabetes

Despite availability of long-acting once-daily insulins, “insulin inertia” (reluctance to start insulin) and “therapeutic inertia” (failure to titrate insulin to agreed glycaemic targets) remain common. In addition, adherence and persistence with insulin, as with most long-term drugs, remains suboptimal, with most people not achieving previously agreed glycaemic goals (Rosenstock et al, 2024). Once-weekly insulin offers increased timing flexibility, lower injection frequency and reduced glycaemic variability. Initial concerns regarding management of acute hypoglycaemia and monitoring have declined following the clinical trial programmes, in which there was no evidence of delay or resistance to hypoglycaemia recovery.

On 13 October 2026, the MHRA authorised basal insulin efsitora alfa (Onswik®), for treatment of type 2 diabetes in adults. NICE Technology Appraisal TA1200 was published on 16 October, recommending insulin efsitora alfa as an option for treating type 2 diabetes in adults. NICE recommends using the least expensive option of suitable treatments, including insulin efsitora alfa or other basal insulins, after discussion of the advantages and disadvantages with the person with type 2 diabetes. NHS funding must be made available within 90 days of publication of the final NICE guidance in England, and within 60 days in Wales, for patients for whom the prescriber considers this drug the best treatment option. The SMC has not published guidance yet.

The UK list price is £46.60 for insulin efsitora alfa 500 units/mL, and £93.20 for 1000 units/mL, both in 3 mL pre-filled pens. Actual costs to the NHS may vary depending on negotiated procurement discounts.

The NICE Technology Appraisal for another once-weekly insulin, insulin icodec, was suspended previously when the manufacturer decided that neither icodec nor its combination with semaglutide were to be launched in the UK. Icodec was discussed in a previous Diabetes Distilled.

Studies of insulin efsitora alfa

In the QWINT (Once Weekly Insulin Treatment) studies, insulin efsitora alfa demonstrated comparable and non-inferior glucose-lowering efficacy to daily basal insulins glargine and degludec. Similar rates of hypoglycaemia (blood glucose <3.0 mmol/L) and severe hypoglycaemia (that requiring third-party assistance) were also observed between the treatment groups – see Box 1 for results.

A systematic review and meta-analysis of randomised controlled trials lasting at least 12 weeks, comparing insulin efsitora alfa with daily basal insulin, was recently published by Hammad et al (2026). This included six trials involving 4116 people, and demonstrated that once-weekly efsitora alfa had comparable effects on HbA_1c, fasting glucose and weight outcomes compared with once-daily basal insulins, with fewer nocturnal hypoglycaemia events in those treated with insulin efsitora alfa. The authors concluded that the comparable benefits and general safety, combined with reduced nocturnal hypoglycaemia and less injection burden, are likely to be associated with improved adherence and patient satisfaction amongst those with type 2 diabetes who transition to efsitora alfa.

Prescribing insulin efsitora alfa

Two dosing regimens are described in the Summary of Product Characteristics for people who are insulin-naïve, with the fixed-dose regimen with simple titration recommended as the primary option. After initial dosing, as with other basal insulins, dose titration should be according to the individualised target and based on the three most recent fasting glucose values. More frequent glucose monitoring and guidance is recommended during switching, especially in people not using continuous glucose monitoring. Always read the Summary of Product Characteristics prior to initiating insulin efsitora alfa.

If switching from once-daily insulin glargine 300 units/mL or twice-daily NPH insulin, the recommended insulin efsitora dose is 80% of the prior total weekly dose (calculated based on the prior daily dose × 7). If the maximum dose for the injection device (400 units for the 500 units/mL pen and 800 units for the 1000 units/mL pen) is exceeded, more than one injection will be needed. Insulin must never be drawn out of a pen device and administered in a separate syringe.

Implications for practice

NICE TA1200 states that insulin efsitora alfa can be used as an option to treat type 2 diabetes in adults, and we are encouraged to use the least expensive basal insulin option, including insulin efsitora alfa, after discussing the pros and cons of the available treatments. TA1200 highlights that once-weekly insulin may be of particular benefit for:

• People with frailty.
• People with a learning disability.
• People who have problems with manual dexterity.
• People with a visual, cognitive or sensory impairment.
• People who find it difficult to take insulin daily, such as those with early-onset type 2 diabetes of working age.

However, NICE recognises that there is “enough evidence to show that insulin efsitora alfa provides benefits and value for money, so it can be used routinely across the NHS if it is considered the most suitable treatment option.”

Although once-weekly insulin is likely to be welcomed by many people with type 2 diabetes currently treated with daily basal insulin, and is particularly important for those in whom district nursing or other assistance and supervision is required for insulin administration, the transition will need to be handled carefully, with increased monitoring. It will be important to avoid being pressurised by people wishing to switch insulins if they do not meet local recommendations for doing so, or if there is a delay in local transition programmes.

The dosing regimens for insulin initiation and for those transitioning from daily basal insulin are described in detail in the Summary of Product Characteristics and in training materials provided by the manufacturer, Eli Lilly. Switching should be undertaken only by clinicians experienced in initiating, managing and titrating insulin.

Although no significant challenges with hypoglycaemia were experienced in the QWINT studies, trial populations do not necessarily reflect the real-world populations likely to be prescribed this insulin; therefore, care and close monitoring will be required during initiation or switches.

The implementation of once-weekly insulin efsitora alfa is expected to free up district nursing time, but we need to be aware of the other vital roles district nurses play while visiting to administer daily insulin, as they can flag up deterioration or concerns which we can then deal with proactively. We all have many people we support who are only just coping with monitoring and administering their own insulin, and who may find changing to once-weekly insulin unsettling or stressful. Time will be needed for shared-care discussions, and we may have to make a judgement call as to who is safe to switch to weekly insulin and who would be at risk of overdose from forgetting their new insulin is once-weekly and accidentally injecting it daily.

As there are two concentrations of insulin efsitora alfa available (500 units/mL and 1000 units/mL, both delivered in a 3 mL KwikPen device), it is important to ensure that people know to check they have received the correct insulin pen prior to administering – as is the case with all insulin pens. However, the dose window of the pen shows the number of units in the dose, regardless of concentration.

If you have not undertaken insulin safety training in the last year, this would be a good time to update. The Six Steps to Insulin Safety programme from the PCDO Society is free and provides a downloadable certificate of completion, which can be added to your appraisal folder. Although it does not yet contain information specifically about once-weekly insulin efsitora alfa, it does contain guidance on choosing and using all other UK insulins safely, and the importance of prescribing all insulin by brand.

Some practice teams are continuing to opportunistically implement the updated NICE NG28 recommendations, as well as ensuring that people on insulin detemir have been switched prior to this insulin becoming unavailable at the end of 2026. Although we need to be aware once-weekly insulin efsitora alfa is available, it may be useful to await local discussions and implementation plans before proactively considering switches or new initiations.