TUESDAY, April 15, 2025 (HealthDay News) -- Pfizer has stopped developing a once-daily pill to treat obesity after a person in a clinical trial showed signs of a possible liver injury.

The company said the injury went away after the person stopped taking the drug, called danuglipron, The Associated Press reported.

The pill was in early testing to help determine the best dose, according to a Pfizer spokeswoman.

The company had planned to move the drug into late-stage trials, typically the final step before review by the U.S. Food and Drug Administration (FDA).

Pfizer will now stop all testing of danuglipron, including its use with other drugs for obesity treatment. However, the company said it still plans to work on other obesity treatments that are in earlier stages of research.

Obesity drugs have become a major focus for pharmaceutical companies. Injectable treatments like Eli Lilly’s Zepbound and Novo Nordisk’s Wegovy have brought in billions in revenue. Zepbound earned nearly $5 billion in 2024 alone, The Associated Press reported.

But these drugs must be injected, which some people do not want to do.

As a result, drugmakers have been racing to develop pill versions. Lilly expects to release new data this year on two oral obesity drugs it is studying.

While demand for these treatments is high, access has been an issue. Some patients face insurance issues or high out-of-pocket costs.

Even with recent price cuts, many of these medications still cost hundreds of dollars per month.

Pfizer had already stopped testing of a twice-daily version of danuglipron in late 2023 after more than half the people in a trial stopped taking it.

More information

The Mayo Clinic has more on prescription weight-loss drugs.

SOURCE: The Associated Press, April 14, 2025