Pfizer discontinues development of obesity pill due to elevated liver enzymes

Pfizer announced Monday it was discontinuing the development of one of its obesity pill candidates due to elevated levels of liver enzymes being detected during clinical trials, while the development of another obesity pill is set to continue.

The pharmaceutical company has been developing two oral treatments for treating obesity and Type 2 diabetes mellitus: danuglipron and lotiglipron.

According to Pfizer, elevated levels of the enzyme transaminase were detected during both Phase 1 and Phase 2 studies for lotiglipron. Higher levels of this enzyme can indicate liver disease or drug-induced liver damage.

Despite these observations, Pfizer said none of the trial participants experienced “liver related symptoms or side effects, there was no evidence of liver failure, and none needed treatment.”

When it came to the other drug candidate, danuglipron, none of the patients enrolled in the program were observed to have higher transaminase levels, the company stated, and development is set to continue depending on the results of an ongoing Phase 2 trial.

“If successful in clinical trials and approved, danuglipron could be in a prime position to differentiate based on profile, including full receptor agonism, which we believe has the potential to translate to robust efficacy,” William Sessa, Pfizer’s chief scientific officer for internal medicine, said in a statement.

The drug candidate from Pfizer differs from the well-known diabetes medication Ozempic; Pfizer’s version is taken orally instead of being injected and is specifically indicated for obesity. Ozempic has grown in public awareness due to its off-label use as a weight-loss drug and its alleged popularity among public figures.

The drug also garnered heightened attention earlier this year when it went into short supply, with criticisms arising from diabetes patients unable to obtain the medication when doctors were prescribing it for off-label use to patients who did not have diabetes.

Both medications are glucagon-like peptide-1 (GLP-1) agonists. This class of drugs mimics the hormone GLP-1, which is released in the gut in response to food intake, slows how quickly food is digested, induces a feeling of satiety, and stimulates the release of insulin.

Other pharmaceutical companies like Eli Lilly and Novo Nordisk, which manufactures Ozempic, are also currently developing oral treatments for weight loss and diabetes.