"Patients on Vivus' Qnexa lose 20lbs more than those on placebo," study

US drugmaker Vivus has reported positive results from a 200-patient, double-blind, placebo-controlled clinical trial of Qnexa (phentermine and topiramate), its investigational oral treatment for obesity. In the study, more than 50% of obese patients in the Qnexa group experienced 10% or more total body weight loss during the 24-week study period. Mean weight loss on an intent-to-treat basis for Qnexa patients was 25.1lbs, compared to 4.8lbs in the placebo group (p<0.0001). The firm noted that the rate of weight improvement in the Qnexa group had not plateaued by the end of the study, adding that the agent was well tolerated with a study completion rate of 92% versus 62% compliance for placebo.