In a significant turn of events in the pharmaceutical industry, Pfizer has announced it is terminating the development of its potential once-daily pill for obesity, known as danuglipron, just before initiating the most extensive and costly phase of clinical trials. The announcement was made on Tuesday, following the identification of a possible drug-induced liver injury in one of the trial participants, which was resolved upon discontinuation of the treatment. This incident raised safety concerns, prompting the company to reconsider its approach to this promising obesity treatment.

According to a company spokesperson, danuglipron was still in the early stages of testing, focusing on determining the optimal dosage for patients. Pfizer had expressed intentions to advance the drug into late-stage clinical trialscommonly regarded as the final hurdle before a potential submission for government regulatory approval. However, given the recent safety incident, the company has opted to take a step back.

Despite this setback with danuglipron, Pfizer remains committed to the development of other obesity treatments that are still in earlier stages of testing. The pharmaceutical sector has seen an increasing focus on obesity treatments, which are emerging as a lucrative area for drug development. For instance, Eli Lilly and Co.s Zepbound generated nearly $5 billion in sales during its first full year on the market in 2024, showcasing the high demand for effective weight-loss solutions.

Currently available leading treatments, such as Zepbound and Novo Nordisks Wegovy, are administered via injection. This has led to a growing interest among drug manufacturers to develop oral pill versions that would be easier for patients to use, particularly for those averse to needles. Eli Lilly is actively pursuing this goal and is expected to release data this year from studies of its own potential oral obesity treatments.

While these drugs have gained popularity and become top-sellers, access remains a challenge for many patients. Shortages and inconsistent insurance coverage have limited availability, and even with recent price reductions announced by both Lilly and Novo, the monthly costs for these treatments can still reach hundreds of dollars, making them unaffordable for uninsured individuals.

In late 2023, Pfizer also announced the abandonment of a twice-daily version of danuglipron, which had progressed to mid-stage testing, after over half of the trial participants ceased taking the medication due to adverse effects.

The recent decision to halt the development of danuglipron also means that Pfizer will discontinue testing the drug in combination with other obesity treatments. Following this news, shares of Pfizer Inc., based in New York, saw a modest increase of 12 cents, bringing the stock price to $22.03 in morning trading on Monday. The company's ongoing commitment to addressing obesity through innovative treatments remains a focal point for its future research initiatives.