- An experimental weight loss drug intended to compete with Novo Nordisk’s Wegovy was able to help obese study participants shed pounds significantly more than a placebo, the drug’s developer, Altimmune, said Tuesday. But the medicine, pemvidutide, was associated with side effects that led nearly one-quarter of trial volunteers to discontinue treatment, the company said.
- At the two highest doses tested in a Phase 2 trial, patients lost an average of about 9% and 11%, respectively, of their body weight after six months of treatment. But more than half of the people taking Altimmune’s drug experienced nausea, exceeding what was seen in testing of Wegovy.
- Altimmune shares fell more than 50% in trading Tuesday. Investors had hoped for better efficacy than what the company reported, and the side effect profile may make it difficult for Altimmune to compete with Wegovy and Eli Lilly’s diabetes drug Mounjaro, which could soon be approved for weight loss.
Obesity treatments represent a huge market opportunity for drugmakers. Some analysts have projected annual sales as high as $50 billion for effective treatments, and developers have recently been sprinting to capitalize.
The race has been focused on drugs in Wegovy and Mounjaro’s class. These medicines, which act on hormones involved in insulin secretion, began as diabetes treatments because of their ability to control blood sugar. But they’ve shown a striking ability to lower weight, too, leading several drugmakers to advance competing programs in lockstep.
Novo, for instance, repurposed its drug Victoza into a weight-loss shot called Saxenda. It followed that pattern with a weekly diabetes shot called Ozempic that’s now known as Wegovy and sold for obesity. Lilly is following close behind with its diabetes drug Mounjaro. It successfully completed one Phase 3 trial in obesity and is weeks away from reporting the results from another study that could support an approval. Pfizer, Amgen and Structure Therapeutics also have prospective obesity medicines in clinical testing.
Mounjaro could become best of the group if it’s able to replicate the results from its earlier Phase 3 study. In that trial, participants given the highest dose lost about a fifth of their body mass, and Lilly reported a lower nausea rate than what’s been observed in testing of Wegovy.
Those data have left Altimmune with little room for error. On a conference call Tuesday morning, executives acknowledged some of the drug’s shortcomings in the trial. Most of the patients who received the highest dose and dropped out of the trial did so after a four-week period in which they gradually received bigger doses. Executives acknowledged on the call that a longer transition period may be necessary in the future.
Altimmune executives also noted that the drug didn’t affect patients’ blood glucose levels, which could boost its prospects as a diabetes treatment. But that profile could limit its effectiveness in another disease, the liver disorder NASH, where physicians try to lower glucose levels.