The drugmaker Pfizer is no longer developing a daily anti-obesity pill, setting back efforts to find new ways to treat obesity that don’t involve regular injections.
The company said it would stop studying the experimental drug, danuglipron, after a participant in one of its clinical trials experienced a possible drug-induced liver injury that ended once the person stopped taking the treatment.
The once-daily version of the pill was in early-stage testing, with researchers trying to figure out the best dose for patients, a spokeswoman said.
The company intended to move the drug into late-stage testing, which is generally the last and most expensive phase before a company submits its potential new treatment to government regulators for approval.
A company official said in a statement that Pfizer still plans to develop other potential obesity treatments in earlier stages of testing.
Obesity treatments have become one of the more promising and lucrative sectors of drug development for pharmaceutical companies. Eli Lilly’s Zepbound, for instance, brought in nearly $5 billion (€4.6 billion) in sales in 2024, its first full year on the market.
But leading treatments like Zepbound and Novo Nordisk’s Wegovy are injectable. Drugmakers are eager to develop an easier-to-take pill version for patients who don't want to deal with needles and daily injections.
Costly treatments
Lilly researchers expect to see data this year from studies of a couple of potential oral treatments it has developed.
While the drugs have become top-sellers, many patients have had a hard time getting them either due to recent shortages or patchy insurance coverage.
Both Lilly and Novo have recently announced price cuts, but the treatments can still cost hundreds of euros per month, putting them out of reach for some people without coverage.
Pfizer said in late 2023 that it would abandon a twice-daily version of danuglipron that had advanced to mid-stage testing after more than half the patients in a clinical trial stopped taking it.
A company spokeswoman said the decision meant Pfizer would also stop testing danuglipron in combination with other drugs to treat obesity.
