LONDON (Reuters) - Eli Lilly's obesity drug Mounjaro will be available through Britain's state health system for some patients from March, after the drugs cost-effectiveness watchdog NICE on Monday gave its blessing.

Mounjaro launched in Britain in February but has been available only for those paying privately, mainly through online pharmacies.

NICE, the National Institute for Health and Care Excellence, is recommending Mounjaro, alongside diet and exercise changes, for people with at least one weight-related condition, such as heart disease or type-2 diabetes, and a body mass index (BMI) - a measure of body fat based on height and weight - of more than 35.

The eligibility guidelines are the same as those issued by NICE in March 2023 for Wegovy, the obesity medication made by rival drugmaker Novo Nordisk.

The criteria mean that around 3.4 million people will be eligible to receive the drug through the National Health Service (NHS).

Mounjaro, a weekly injection, is part of a class of medicines known as GLP-1 analogues originally developed to help control blood sugar in patients with type-2 diabetes but also found to suppress appetite and promote a feeling of fullness. The drug led to an average weight loss of nearly 23% in clinical trials.

Mounjaro will cost the NHS 122 pounds ($153) per patient per month for the highest dose, which NICE judged to be cost-effective given the costs to the health system of obesity and related conditions.

(Reporting by Maggie Fick; Editing by Kevin Liffey)