Mounjaro What is the 'King Kong' of weight loss drugs?

Mounjaro, known as the "King Kong of weight-loss drugs", will be available to patients on the NHS in England, but this week it was announced it would be prioritised to people with the highest needs, with the rollout expected to extend over a 12-year period.

- Nicola Davis

We take a look at why it is in such demand, and the impact it could have on the nation's health.

What is Mounjaro?

Mounjaro is one of a growing number of weight-loss jabs, and is produced by the pharmaceutical company Eli Lilly. It is a once-a-week injection that contains the drug tirzepatide, and is also used to help improve blood sugar in people with type 2 diabetes.

How does it differ from Wegovy?

Wegovy is also licensed for weight loss, but contains the drug semaglutide and is made by the Danish company Novo Nordisk.

Both semaglutide and tirzepatide mimic a hormone produced in the body called GLP-1 - a substance released in the gut when we eat. This hormone slows the rate at which food is emptied from the stomach, acts on the brain to reduce appetite, and triggers a rise in the production of insulin.

However, tirzepatide also mimics another hormone known as GIP (glucose-dependent insulinotropic polypeptide).