A phase 2 study evaluating the safety and efficacy of the investigational drug Qnexa for the treatment of obstructive sleep apnea (OSA) showed statistically significant improvement in the apnea/hypopnea index (AHI) in study participants with OSA treated with the drug for 28 weeks. Qnexa-treated patients in the study also experienced significant weight loss and improvements in blood pressure and overnight blood oxygen levels.

The majority (69%) of patients treated with Qnexa for 28 weeks had a reduction in sleep apnea events. Qnexa treatment reduced the number of apnea/hypopnea events from a mean of 46 events per hour of sleep to 14. Placebo patients saw a reduction from a mean 44 events per hour of sleep to 27.

"We know that substantial weight loss can significantly improve sleep apnea. These phase 2 data suggest that Qnexa, if approved for this indication, may be a promising treatment for OSA. We have submitted the study results for presentation at a scientific meeting. We also look forward to meeting with the FDA to discuss the results of this study and to determine the regulatory path for approval," said Leland Wilson, chief executive officer of VIVUS.

The phase 2 study (OB-204) was a single-center, randomized, double-blind, placebo-controlled parallel group trial including 45 obese men and women (BMI 30 to 40 kg/m2, inclusive), 30 to 65 years of age. Patients enrolled had a baseline AHI greater than or equal to 15. In addition to receiving active or placebo drug, all patients were provided with an intensive lifestyle modification program.

Additionally, Qnexa-treated patients lost 10.2% body weight, or 23.8 pounds in 28 weeks—compared to 4.3% or 10.4 pounds for patients treated with placebo. Mean overnight oxygen saturation was also significantly improved in Qnexa patients (P <0.014 active versus placebo).

The data follow a December 2009 submission of VIVUS’s New Drug Application to the US Food and Drug Administration for Qnexa for the treatment of obesity, including weight loss and maintenance of weight loss, in patients who are obese or overweight with comorbidities.