Phase 2 Trial
Definition
The second stage of clinical testing, designed to evaluate a drug's efficacy, optimal dosing, and safety in a larger group of patients with the target condition, typically enrolling hundreds of participants.
Phase 2 Trial
A Phase 2 clinical trial is the stage of drug development where therapeutic efficacy is first rigorously evaluated in patients with the target disease or condition. These trials build on the safety and pharmacokinetic data from Phase 1 studies and typically enroll hundreds of participants. Phase 2 trials are often randomized, double-blind, and placebo-controlled to provide reliable evidence of treatment effects.
Phase 2 studies frequently employ dose-ranging designs, in which participants are randomized to different dose levels of the investigational drug and a placebo control. This allows researchers to characterize the dose-response relationship, identify the doses most likely to provide meaningful efficacy with acceptable tolerability, and select the optimal doses for Phase 3 pivotal trials. The duration of Phase 2 studies varies but often ranges from 12 to 48 weeks for chronic conditions like obesity and type 2 diabetes.
Retatrutide’s Phase 2 program included two landmark trials: a 48-week obesity trial published in the New England Journal of Medicine (NCT04881706) and a 36-week type 2 diabetes trial published in The Lancet (NCT04867785). These studies were pivotal in establishing retatrutide’s efficacy profile, demonstrating up to 24.2% weight loss and significant HbA1c reductions, and in selecting doses for the Phase 3 TRIUMPH program.