Pfizer Inc. (PFE) on Tuesday announced positive topline results from the Phase 2b VESPER-3 study evaluating monthly maintenance dosing of its ultra-long-acting, injectable GLP-1 receptor agonist PF'3944 in adults with obesity or overweight without type 2 diabetes.
The study's dual objectives were to show that PF'3944 could continue to deliver weight loss when patients switch from weekly to monthly subcutaneous injections, and to demonstrate that the monthly dosing regimen could maintain a well-tolerated and favorable safety profile.
VESPER-3 is an ongoing 64-week study evaluating a transition from weekly titration to monthly dosing of PF'3944 across four different dosing regimens, compared with placebo.
The trial achieved statistically significant results, with up to 12.3% mean placebo-adjusted weight loss at week 28. The primary endpoint of weight reduction was met in all four dose regimens tested. PF'3944 also maintained a well-tolerated and favorable safety profile through week 28
Pfizer said the data showed robust and continuous weight loss after participants switched to monthly dosing, with no plateau observed at week 28. The company added that the results suggest further weight reduction is expected as the study continues through week 64.
Pfizer shares were down more than 1% in pre-market trading after closing at $26.66 on Monday, up 0.83%.
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