Pfizer Inc.’s stock tumbled 4% premarket 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.
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.
Those have proved effective and popular in helping patients manage diabetes and lose weight and have boosted the stocks of Novo Nordisk
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
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.
Pfizer’s stock has fallen 40.5% in the year to date, while the S&P 500
has gained 19%.