Mounjaro Becomes Second Obesity Drug Approved for Use in England

The medical regulator for England has authorized a second medication to combat obesity, offering patients and doctors what it claims is a more effective option than semaglutide.

Draft guidance from the National Institute for Health and Care Excellence (Nice), released on Tuesday, recommends that severely obese individuals in England should receive tirzepatide, marketed as Mounjaro in the UK. This approval allows doctors to prescribe tirzepatide to people with a body mass index (BMI) of at least 35 and at least one weight-related condition such as heart disease, type 2 diabetes, or sleep apnoea, once final guidance is issued within three months.

Nice’s draft guidance states, “Clinical trials indicate that tirzepatide, when combined with diet and exercise support, is more effective compared to diet and exercise support alone. Indirect comparisons suggest it is also more effective than semaglutide when used alongside diet and exercise support.”

Semaglutide, known as Wegovy, was the first anti-obesity drug approved by Nice in 2022 and is manufactured by Novo Nordisk, while Mounjaro is produced by Eli Lilly.

Experts anticipate that Mounjaro will be more accessible to patients than Wegovy, as general practitioners (GPs) rather than just NHS weight management services can prescribe it, likely leading to increased uptake of obesity medications.

Clinical trials have demonstrated that tirzepatide can help users achieve a weight loss of 22.5% of their body weight over 72 weeks, compared to 16% over 68 weeks with Wegovy.

Dr. Nerys Astbury, an associate professor at Oxford University specializing in diet and obesity, commented, “Expanding pharmacological options for healthcare professionals outside specialist weight management settings can only benefit individuals living with obesity.”

Nice estimates that a four-week supply of pre-filled pens of Mounjaro will cost between £92 and £122, depending on dosage size, seen as a worthwhile NHS investment due to reduced risks of serious health complications.

Patients prescribed Mounjaro can use it as long as needed, unlike Wegovy, which is limited to two years by Nice guidelines.

Dr. Simon Cork, a senior lecturer in physiology at Anglia Ruskin University, noted that despite the BMI threshold of 35 set by Nice for Mounjaro, limiting its initial availability, demand may mirror that seen for Wegovy.

Professor Sir Stephen O’Rahilly, a clinical biochemistry and medicine professor at Cambridge University, emphasized that amid rising rates of severe weight gain, medications like tirzepatide will play a crucial role in improving the longevity and health of people with obesity.

However, Nice also stipulated that doctors should discontinue Mounjaro if patients fail to achieve at least a 5% reduction in body weight within six months.

(Note: The article was amended on June 7, 2024, to clarify that doctors will be able to prescribe Mounjaro within three months of final guidance issuance, not immediately.)