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Pfizer On Monday, he said he would be closing the development of an experimental daily weight loss drug after a patient experienced liver damage that could be caused by drugs in his trial.
A Pfizer spokesperson said in a statement that the patient had no experience with liver-related symptoms or side effects. They added that the patient’s liver enzyme “recovered rapidly” after ceasing to take tablets, an oral GLP-1 drug called danuglipron. The statement suggests that patients’ liver enzymes have been elevated, a problem that often indicates damage to organ cells and is associated with other obesity drugs.
The case occurred in a trial that rapidly increased tablet doses over a short period of time, the spokesman said. According to the release, Pfizer’s decision to halt drug development came after “an overall review of information, including all clinical data generated so far for Danaglipron and recent input from regulatory authorities.”
“We are disappointed to halt the development of Danuglipron, but we continue to be committed to evaluating and moving forward the promising programme to bring innovative new medicines to patients,” he added that the company is still developing other weight loss drugs.
The announcement will be added to a series of set-offs in the company’s bid to win slices of the booming market for GLP-1. Pfizer is one of several drug makers to bring more convenient weight loss pills to the dominant space for weekly injections, but it has been years behind competitors like its competitors Eli Lily and Novo Nordisk.
Some Wall Street analysts expect the GLP-1 industry to be worth more than $150 billion by the early 2030s. According to estimates from some analysts, oral GLP-1 is worth its total of $50 billion, while injections could account for the rest.
This is not Pfizer’s first set, especially with Danuglipron. The company discontinued pills twice a day in December 2023 after patients complained of drug resistance in a mid-stage study.
However, Pfizer appeared to be confident in the one-day format of Danagripron in July.
Despite the decision to dispose of the drug, Pfizer said Monday that the studies met important goals and identified specific forms and dosages that could provide “competitive efficacy and tolerability” in late trials.
The company also noted that the rate of liver enzyme elevation in people who took Danuglipron is consistent with approved GLP-1 drugs, which are based on a safety database of over 1,400 patients who took Pfizer’s medication.
Pfizer discarded different day obesity pills in June 2023 after patients taking the medication had higher liver enzyme levels in mid-stage trials. Investors have since been pessimistic about the company’s potential in the GLP-1 field.
Still, Pfizer has other experimental obesity drugs in its pipeline early in its development, which appears to be functioning differently from the treatments in which discones are present. This includes another intestinal hormone blocking, called GIPR, another intestinal hormone that entered the Phase 2 trial last year, and oral GLP-1 once a day in the Phase 1 trial.
Pfizer believes drugs targeting GIPR could be more effective and easier to make, former chief science officer Michael Dorsten, who later left the company, told investors in October. He added, “There are so many applications in the GLP-1.”
Pfizer’s danagripron promotes weight loss by targeting GLP-1. This is also Novo Nordisk’s weight loss infusion Wegovy and Ozempic work in diabetes treatment. Eli Lilly’s weight loss infusion zepbound and diabetes shot Mounjaro’s target GLP-1, but also activated another intestinal hormone called GIP.
The only oral GLP-1 ever approved by the Food and Drug Administration is Novo Nordisk’s Rybelsus, which treated type 2 diabetes in 2024 and sold approximately $3.38 billion.
Pfizer’s Monday announcement comes as the company regains its foothold and recovers its share price after a rapid decline in its COVID business. Pfizer is betting on the cancer drug pipeline to bring about long-term growth, but emphasizes obesity is a key focus.
