Pfizer shares dropped by nearly 6 percent on Friday after the pharmaceutical company announced that its twice-daily anti-obesity pill will not advance to Phase 3 clinical trials. After a previous stock drop in the post-COVID years, the drugmaker was banking on its new weight loss drug, danuglipron, to recoup the losses — but reports of widespread nausea and vomiting have halted those plans.
The first two phases of Pfizer’s clinical studies administer between 40 and 200 milligrams of danuglipron to 600 obese adults who do not have Type 2 diabetes. The trials studied weight loss results at 26 and 32 weeks to determine the ideal dosage.
Initially, results were promising, with patients losing between 6.9 percent and 11.7 percent of their body weight by week 32. However, by the mid-stage of the study, upwards of 50 percent of the participants stopped taking the drug. Up to 73 percent reported nausea, 47 percent experienced frequent vomiting, and 25 percent dealt with diarrhea.
Danuglipron marked Pfizer’s latest effort to secure a place in the booming anti-obesity drug market, competing with compounds like Novo Nordisk’s Ozempic and Eli Lilly’s Zepbound. Like its competitors, danuglipron mimics GPL-1, an intestinal hormone that signals when the body is no longer hungry.
Initially developed as treatments for diabetes and related obesity, the compounds took off as a trendy weight loss solution, and according to Pfizer CEO Albert Bourla, the successful launch of danuglipron was poised to give the company a $90 billion slice of the burgeoning market.
However, in a statement from the company published on Friday, it was revealed that “at this time, twice-daily danuglipron formulation will not advance into Phase 3 studies” based on the side effects.
Following this announcement, Pfizer shares dropped by 6.1 percent during midmorning trading, falling to a low of $28.62 apiece. This marked the lowest stock value for the company since March 2020. Pfizer’s value has fallen 44 percent this year alone, putting it on track for its worst year ever.
Pfizer will continue testing a once-a-day version of danuglipron until early next year, at which point clinical data will “inform a path forward.”