The co-primary endpoints for these studies will evaluate the differences between treatments in mean percent weight loss and in the percentage of subjects achieving weight loss of 5% or more. Patients will be studied over 28 weeks.
The Equate study will enroll approximately 700 subjects in up to 35 centers. Patients will undergo a four-week dose escalation period followed by 24 weeks of treatment. The study is a randomized, double-blind, placebo-controlled, seven-arm, prospective trial with subjects randomized to receive once-a-day treatment with mid-dose Qnexa (7.5mg phentermine/46mg topiramate), full strength Qnexa (15 mg phentermine/92 mg topiramate), the respective phentermine and topiramate constituents, or placebo.
At randomization, subjects will be instructed to follow a hypocaloric diet representing a 500-calorie/day deficit and advised to implement a simple lifestyle modification program throughout the study period.
Vivus has also completed the special protocol assessment process for this trial with the FDA.
Wesley Day, vice president of clinical development for Vivus, said: “The initiation of the Equate study completes our plans for Phase III studies of Qnexa. The Equate study will evaluate two doses of Qnexa over six months and should give us an early look at the outcomes of the larger pivotal Phase III studies.”