Regeneron’s Weight-loss Drug Helps Patients on Wegovy Preserve Muscle

(Reuters) -Regeneron said on Monday its experimental drug helped patients preserve up to 51% of lean mass and lose more fat when used in combination with Novo Nordisk’s popular obesity drug Wegovy in a mid-stage trial.

In the 599-patient study, those on Wegovy alone lost about 7.9 pounds of muscle, while those on a combination of Regeneron’s trevogrumab and Wegovy lost up to 4.2 pounds.

The combination helped patients shed up to 11.3% of their body weight compared with 10.4% for those on only Wegovy.

The results mark an early win for Regeneron in the race against nearly a dozen companies to develop obesity treatments that preserve muscle, as they vie for a share of the potential $150 billion weight-loss drug market.

Regeneron also said it will license an experimental obesity drug from China’s Hansoh Pharmaceuticals in a deal worth up to $2.01 billion.

Weight-loss drugs from current market leaders Novo Nordisk and Eli Lily help patients shed fat but also lead to muscle loss, which can increase the risk of falls and decrease overall strength.

Several companies, including Lilly and smaller rivals Scholar Rock and Veru are working on drugs that target proteins tied to muscle preservation or growth, but they are all years away from approval.

Veru’s drug, enobosarm, has shown to help older patients on Wegovy lose 71% less muscle compared to the Novo drug alone in a mid-stage trial. Data from Lilly and Scholar Rock is expected later this year.

The U.S. Food and Drug Administration has said these drugs need to show additional weight loss or other benefits, such as improvement in patients’ strength, to be considered for approval. But it has not given clear guidance on what data will be enough for approval.

Wall Street analysts have said that an unclear regulatory path and showing clean safety are key challenges for companies developing muscle-preserving drugs.

A triple drug combination of Wegovy, Regeneron’s trevogrumab and another antibody garetosmab helped patients lose 13.2% of their body weight. But 28% of the patients stopped treatment due to side effects – the highest rate among all groups tested in the study.

“Incremental improved weight loss from double and triple therapy are promising,” said BMO Capital Markets analyst Evan Seigerman, adding that late stage data will be crucial to understand safety profile of Regeneron’s drug.

Two patients in the triple combination group died, Regeneron said, adding that it has not yet identified if the deaths were connected to the treatment.

Regeneron expects full data from the study later this year.

(Reporting by Mariam Sunny in Bengaluru and Bhanvi Satija in New York; Editing by Shailesh Kuber and Shinjini Ganguli)