Pfizer’s stock falls 4% after halting trial of obesity drug due to side effects
Pfizer Inc.’s stock tumbled 6% Friday, after the company said it would not move to a Phase 3 trial of a twice-daily formulation of a weight-loss drug after patients in an earlier study had a lot of side effects.
The stock was on track for its biggest one-day percentage decline since June 11, 2020, when it fell 7.3%, according to Dow Jones Market Data. It’s also headed for its lowest close since March 25 of 2020.
Pfizer’s stock has fallen 44% in the year to date, while the S&P 500
SPX,
has gained 19%. That’s putting it on pace for its worst year on record, based on available data going back to January 21 of 1972.
The company
PFE,
said the Phase 2b study of its oral GLP-1 candidate danuglipron in adults with obesity and Type 2 diabetes met its primary endpoint of statistically significant change in body weight compared with placebo.
Twice-daily dosages of danuglipron demonstrated placebo-adjusted weight reductions ranging from 8% to 13% at 32 weeks and 5% to 9.5% at 26 weeks.
However, “While the most common adverse events were mild and gastrointestinal in nature consistent with the mechanism, high rates were observed (up to 73% nausea; up to 47% vomiting; up to 25% diarrhea),” the company said in a statement.
“High discontinuation rates, greater than 50%, were seen across all doses compared to approximately 40% with placebo.”
Pfizer is not planning to move the twice-daily formulation to Phase 3 studies, but said it believes a once-daily formulation could play a role in obesity treatment.
“Results from ongoing and future studies of the once-daily danuglipron modified release formulation will inform a potential path forward with an aim to improve the tolerability profile and optimize both study design and execution,” said Dr. Mikael Dolsten, chief scientific officer and president of Pfizer research & development.
Like many drug companies, Pfizer was working to develop an oral version of the new class of weight loss drugs that could become alternatives to popular injectables like Wegovy and Ozempic.
Those have proved effective and popular in helping patients manage diabetes and lose weight and have boosted the stocks of Novo Nordisk
NOVO.B,
NVO,
and Eli Lilly & Co.
LLY,
who are leading the way for now.
Novo Nordisk is the developer of Wegovy and Ozempic, while Eli Lilly is behind Mounjaro. Those are GLP-1 receptor agonists, which can mimic the effects of a gut hormone that helps control appetite and blood-sugar levels.
Both Mounjaro and Ozempic have U.S. regulatory approval for treatment of Type 2 diabetes — not weight loss. But Eli Lilly’s Zepbound, which has the same active ingredient as Mounjaro, and Wegovy, which has the same active ingredient as Ozempic, are approved by the U.S. Food and Drug Administration for weight management.
A real-world study published this week found that Mounjaro is significantly more effective than Novo Nordisk’s Ozempic in producing weight loss in patients
For more, read: Eli Lilly’s Mounjaro three times more effective than Ozempic for weight loss, real-world study finds
Pfizer has already terminated the development of a similar treatment to danuglipron called lotiglipron, after early clinical data showed potential for elevated liver enzymes in some patients.
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