Eli Lilly & Co.’s Mounjaro is being recommended for weight loss for some UK patients with obesity, in draft guidance that could see the National Health Service offer a rival drug to Novo Nordisk A/S’s hit treatment Wegovy. 

Patients with a body mass index of at least 35 and at least one weight-related co-morbidity should take Mounjaro, according to the UK’s drug cost regulator.

The National Institute for Health and Care Excellence also recommended Tirzepatide — which is sold under the brand name Mounjaro in the UK and Zepbound in the US — for people with a lower BMI threshold from several ethnic backgrounds including Black African and South Asian. The medication would be an option alongside a reduced calorie diet and increased physical activity. 

The recommendations are still in draft form and could change following input from an open consultation.

If the guidance is confirmed, Mounjaro will challenge Novo’s Wegovy, which is recommended for patients with obesity if they are in a specialist weight-management service. 

The regulator said Mounjaro might be more effective than Wegovy, if taken alongside diet and exercise support, according to the draft recommendation text. 

The regulator said patients on Mounjaro should consider stopping the drug if less than 5% of their initial weight has been lost after 6 months. However, it recommended not including a long-term stop date for patients taking tirzepatide, which could potentially deal a blow to Novo as usage of Wegovy for obesity on the NHS is capped at a maximum of two years. 

Mounjaro received backing from the cost regulator last year for treating patients with type 2 diabetes, paving the way for broader use of the drug for weight loss. 

Both Mounjaro and Wegovy are already available privately in the UK for patients with a BMI of 30 or over and patients with a BMI of 27 or more who also have another weight-related health problem such as high blood pressure. Access to Wegovy through the NHS is difficult, however, as specialist weight-management services are limited. 

“This class of injectable drug is currently expensive, providing particular challenges to a taxpayer-funded health system like the NHS,” said Stephen O’Rahilly, professor of clinical biochemisty and medicine at the University of Cambridge in comments shared by the Science Media Centre. 

“In the longer term, these drugs significantly reduce the risks of developing distressing and expensive complications such as Type 2 diabetes, heart attacks and kidney failure but their cost provides an immediate financial challenge at a time when NHS budgets are tight.”