The company is planning a Phase 3 trial testing physical function in older people with obesity. Shares fell by nearly half following the news.

Dive Brief:

• An experimental muscle-building drug helped people with obesity taking Wegovy preserve significantly more lean mass than Wegovy alone in a 16-week trial, the drug’s developer, Veru, said Monday.
• Trial volunteers taking Wegovy with Veru’s drug, called enobosarm, lost on average 1.2% of their lean body mass, compared with 4.1% in the Wegovy-only group. The trial tested two doses of enobosarm in people 60 years and older with obesity or who were overweight, and also evaluated fat loss, overall body weight loss and physical function.
• Drugs that can help improve body composition alongside weight loss medicine are an emerging focus in obesity treatment, especially in older people who can become more frail if they lose too much muscle or bone mass. Veru shares fell as much as 50% following the announcement, and were changing hands at 65 cents apiece in late morning trading.

Dive Insight:

Enobosarm has been in clinical testing for some time as a treatment for dangerous weight loss in cancer patients, breast cancer and stress urinary incontinence. At one time, it had been part of a partnership between biotechnology company GTx and Merck & Co. to develop this class of drugs known as selective androgen receptor modulators, or SARMs.

Veru initially tested it as a breast cancer drug, but decided to pursue using it as an adjunct treatment to obesity because it saw the body composition issue in people taking GLP-1 drugs, like Novo Nordisk’s Wegovy and Eli Lilly’s Zepbound, as an unmet medical need.

The Miami-based company enrolled 168 people in the trial, randomizing 100 to take 3 milligrams or 6 milligrams of enobosarm once a day in addition to their weekly Wegovy shots, with the rest receiving placebo.

While people receiving enobosarm lost less of their lean muscle, the weight loss in the two groups was roughly the same: people who took enobosarm lost on average 4.4 kilograms and those who got placebo lost 4.7 kilograms. People who took enobosarm had significantly better scores on a stair-climb power test, with only 19.4% of them losing 10% or more on the test compared with 42.6% in the placebo arm.

Veru said safety data remains blinded to trial researchers until completion of an extension study. Aggregated data has “not shown significant differences” from previous trials of enobosarm, the company added. An analysis of those data conducted by Veru and academic collaborators found that side effects were largely equal between enobosarm and placebo recipients.

Veru CEO Mitchell Steiner said in a statement that the company plans to meet with the Food and Drug Administration about advancing enobosarm into Phase 3 testing. The company plans on a similar trial design, but with 470 patients measuring changes over 52 weeks, with stair-climb power as the primary goal.