Altimmune touts 'best-in-class' lean mass results for weight loss therapy in quest to outdo big time competitors

After a full data analysis, Altimmune is heralding phase 2 obesity data for pemvidutide as “best-in-class” for spurring weight loss while preserving lean mass.

The small biotech is going up against some industry heavyweights with pemvidutide, a GLP-1/glucagon dual receptor agonist currently in mid-phase testing for obesity and several other indications. Altimmune already released data late last year linking the therapy to mean weight loss of 15.6% compared to 2.2% for placebo at week 48.

Now, the company has shared data from a subgroup of 50 patients that finds just 21.9% of weight loss was attributable to lean mass, while 78.1% was fat loss at week 48. Wegovy has been associated with lean mass loss of up to 40% at the end of 68 weeks. 

CEO Vipin Garg, Ph.D., called this a “best-in-class” performance in a Sunday statement. The data was presented at the American Diabetes Association’s 84th Scientific Sessions.

“The preservation of lean mass observed in this trial is better than reported historically with diet and exercise programs and greater than that associated with other incretin weight loss drugs, where lean mass has accounted for as much as 40% of total weight loss,” Garg said. “Preservation of lean mass, which is primarily muscle tissue, is believed to be important in maintaining healthy weight loss and physical function. We believe that this best-in-class muscle preservation further adds to the differentiation of pemvidutide in the treatment of obesity.”

The study enrolled 391 people who had obesity or were overweight and had at least one co-morbidity, excluding diabetes. Patients received one of three doses or placebo weekly for 48 weeks along with diet and exercise. Patients achieved weight loss of 10.3%, 11.2%, 15.6% and 2.2% at the 1.2 mg, 1.8 mg, and 2.4 mg doses and placebo, respectively. The weight loss numbers were previously reported in November 2023.

A subgroup of the patients were evaluated for body composition, which is the new data today. Altimmune said that 50 patients received a full MRI body scan for a composition analysis, showing the breakdown of lean mass and fat loss.

Pemvidutide also lowered serum lipids and improved blood pressure without an imbalance in cardiac events, arrhythmias or clinically meaningful increases in heart rate, according to Altimmune.

All of these secondary results are key to the biotech’s efforts to come from behind Novo Nordisk and Eli Lilly, which have huge head starts in the obesity market.

Elsewhere at the ADA meeting, Altimmune showcased phase 1 data for pemvidutide in patients who are overweight or have obesity but do not have type 2 diabetes. The aim of the trial is to measure the drug’s impact on cardioinflammatory lipids, which can elevate the risk of cardiovascular disease.

After 12 weeks, patients had serum lipid reductions of 28%, 26% and 38% across the 1.2 mg, 1.8 mg and 2.4 mg doses, respectively. These reductions were not correlated with weight loss, which Altimmune said suggests the results are due to pemvidutide’s impact on lipid metabolism.

The analysis showed that the drug significantly reduced small dense LDL-C, short-chain diglycerides with a higher degree of saturation, lysophosphatidylinositols, lysophosphatidylcholines and sphingolipids, which are associated with cardiovascular disease risk.

“These data add to the differentiated profile of pemvidutide and reinforce its potential to reduce inflammatory lipids associated with cardiovascular plaque formation and cardiovascular risk in patients with obesity,” Garg said in a separate release on the lipid data from June 22.