Unlock the Editor’s Digest for free

Mounjaro will become available “within weeks” in Great Britain for treatment of both diabetes and obesity, after the medicines regulator authorised US pharma company Eli Lilly on Thursday to sell the weight loss drug in an injectable pen.

The product, which has achieved 22.5 per cent body weight loss in trial results, will rival Novo Nordisk’s Wegovy, which has been in short supply in the UK since its September launch with celebrity endorsements and dramatic weight-loss results boosting demand.

The Medicines and Healthcare Products regulatory agency first authorised Mounjaro, also known as tirzepatide, in November but not enough of the regular format of the drug was available to supply the UK.

After the MHRA announced authorisation of Eli Lilly’s “KwikPen” on Thursday, a format that provides four doses in one device, the company has said it will now be able to supply the drug to England, Scotland and Wales.

“The MHRA is the first major regulator in the world to issue marketing authorisation for the alternative KwikPen presentation for tirzepatide, demonstrating their clear focus on speeding innovation to help patients. This will enable Lilly to begin supply to the UK within weeks,” said Laura Steele, head of UK and northern Europe at Lilly.

More than one in four adults in England are obese, according to the Health Survey for England 2021. The drug has been approved for use by adults with type 2 diabetes and for obese people with a BMI of 30 or above, or overweight people with a BMI of 27 and above, when they also have illnesses such as high blood pressure, sleep apnoea or diabetes.

Mounjaro — also sold under the brand name Zepbound in the US — helped the $610bn US pharma company become the world’s most valuable drugmaker last summer.

But Eli Lilly declined to say how much of the product would be available in Britain, or which pharmacies will stock the product.

Patients in Northern Ireland will not have access to the pen.

It is also unlikely that Eli Lilly will provide enough doses of the drug to Britain to meet the demand for weight loss treatments.

Popularity of the medication has also left diabetics short of medicines. Earlier this month the Department of Health and Social Care recommended that doctors avoid prescribing diabetes drugs such as Novo Nordisk’s Ozempic for weight loss in a bid to ringfence supplies.