Lilly, Novo, Pfizer look to new weight loss drugs

Drugmakers are only months into introducing GLP-1 pills and navigating huge changes in how patients pay for weight-loss drugs.

Even so, they’re already outlining their visions for the future of obesity drugs.

At the American Diabetes Association’s Scientific Sessions in New Orleans last week, drugmakers pitched doctors and investors on the idea of new shots and pills, drugs that can be taken less frequently, and new treatments beyond GLP-1s that could come with fewer side effects. The attendees debated where all these new treatments might fit in, especially with Eli Lilly currently dominating the market for shots and impressing attendees with data from its experimental triple-acting drug retatrutide that produced the most weight loss seen yet.

Lilly and rival Novo Nordisk showcased new GLP-1 pills they each introduced earlier this year. Both companies made the case that oral options are bringing more people into the market for weight loss drugs, with Novo touting that prescriptions of its Wegovy pill reached more than 3 million just five months into the launch.

Behind the two market leaders are a wave of new entrants hoping to get into the massive market in the coming years.

Structure Therapeutics and AstraZeneca each shared mid-stage data from their respective GLP-1 pills. Should those oral drugs succeed in Phase 3 trials, they would likely come to the market around 2029, three years behind Lilly, which introduced its small molecule pill Foundayo earlier this year (the Wegovy pill is an oral peptide).

Structure Therapeutics CEO Ray Stevens thinks there will still be plenty of room in the market by then.

“Who wins at the end of the day with competition? Patients, and that’s really what this is all about,” Stevens said, adding that being the second small molecule drug will be important. “We’re really pushing hard to get into that second position behind orforglipron, now Foundayo.”

Pfizer also unveiled mid-stage data from a shot it gained through its $10 billion acquisition of Metsera. The drug showed the potential to be given monthly, which Pfizer thinks would be more convenient than the currently weekly shots. Another drugmaker, Amgen, is testing a different drug that could be given monthly or possibly even quarterly.

Susan Sweeney, Amgen’s executive vice president of obesity and related conditions, said the company sees an advantage in people not needing to take a weekly injection and instead thinking about treatment as little as four times a year.

“For somebody who’s lived with obesity for a long time, it can be a major advantage in not remembering your disease,” she said.

Some companies are looking beyond GLP-1 and other hot targets like GIP and glucagon to emerging areas like amylin, another hormone produced in the pancreas that helps people feel full. One company is Zealand Pharma, which presented mid-stage data from a drug called petrelintide that it’s developing with Roche.

The experimental shot helped people lose almost 11% of their body weight — less than the currently available injections Wegovy and Zepbound. But Zealand touted that fewer people taking the drug vomited than those in the placebo group.

“I truly believe that when these amylin [drugs] launch, we can have that, what I’ve described as an iPhone moment, because patients are so aware of the experience they have on the GLP-1s, and once you launch a new modality that gives you a better experience, people will queue up to get access to that new weight loss medication rather than staying on the more cumbersome medicines,” said Zealand CEO Adam Steensberg.

Like the other potential new entrants, it will be years before Zealand’s drug becomes available. Market leader Lilly is developing its own amylin analogue called eloralintide that’s already in Phase 3 trials.

At this year’s ADA, Lilly also presented Phase 3 results from its triple agonist retatrutide. That drug activates the GLP-1, GIP and glucagon receptors, producing dramatic weight loss.

At the highest dose, people lost an average of 28% of their body weight when they took retatrutide and stayed on it as prescribed in the trial. Lilly CEO Dave Ricks sees the drug a way to help people with a body mass index over 40, or the highest classification of obesity, achieve a healthy weight, something that’s not possible if they have an average response to Lilly’s current shot Zepbound.

“We showed what’s possible, which is meaningful: Almost half the people lose more than 30% of their body weight,” Ricks said. “So if you do start at a higher level, you can really get to a more healthy state, which is everyone’s goal, I think.”