(Reuters) – Pfizer announced on Monday that it had interrupted the development of Danuglipron, its experimental compressed tablet against obesity, after a patient participating in a clinical trial underwent a potential hepatic lesion induced by the drug, which resolved after stopping treatment.

Pfizer tested different doses of a daily version of Danuglipron, after having abandoned at the end of 2023 the development of a biquotidian administration version. Most patients then interrupted the mid-term test due to a high level of side effects, such as nausea and vomiting.

Danuglipron belongs to a class of drugs aimed at targeting the GLP-1 intestinal hormone.

Milder drugs arouse lively interest from pharmaceutical companies and investors due to annual sales forecasts of up to $ 150 billion (131.67 billion euros) in the coming years, demand being supported by new very effective treatments.

The market is currently dominated by the Wegovy of Novo Nordisk and the Zepbound of Eli Lilly, which are both administered in the form of weekly injections. Several companies work on potentially more practical GLP-1 pills, including Eli Lilly, which should soon announce the results of the phase 3 trial for its medicine orforglipron.

Pfizer clarified that the dose optimization studies of the Danuglipron in a single daily intake had reached the main pharmacokinetic objectives, and the overall frequency of the elevations of liver enzymes in 1,400 trial participants was in accordance with that of the drugs approved in the same class. However, a patient has developed liver injury.

Pfizer said that he had decided to stop the study of the molecule “after examining all the information, including all the clinical data generated to date for Danuglipron and recent comments of the regulatory authorities”.

However, the group added that it would continue to develop another experimental oral drug targeting a different hormone, the GIPR, as well as other projects in the field of obesity.

“Cardiovascular and metabolic diseases, including obesity, remain major areas where medical needs remain dissatisfied, and we plan to continue to use our global capacities to advance our portfolio of experimental treatment,” said Chris Boshoff, scientific director of Pfizer, in a press release.

Pfizer added that data from the Danuglipron clinical program would be presented at a next scientific meeting or published in a reading committee review.

(Written by Deena Beasley, Elena Smirnova, edited by Augustin Turpin)

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