Qnexa® Obesity   

The Market

The prevalence of obesity continues to be a health concern and affefcts a large and growing proportion of the population, including more than one third (more than 60 million) of Americans. Worldwide more than 400 million people are obese. Obesity directly contributes to numerous life-threatening conditions: diabetes,cardiovascular disease, hypertension and stroke. Presently there are a number of anti-obesity agents in clinical development.

The worldwide obesity therapeutic market is currently estimated to be approximately $1 billion. Analysts speculate that the potential market for obesity in the United States could approach $5 billion.

The Product

Qnexa® is a once a day, proprietary, oral, controlled-release formulation of low dose phentermine and topiramate, which is believed to address both appetite and satiety - the two main mechanisms that impact eating behavior - in one capsule. Qnexa appears to induce significantly greater weight loss than either individual compound. Further, clinical trials conducted with Qnexa have demonstrated superior efficacy and a significantly improved safety profile as compared to either active agent alone or other currently available therapeutic options.

Phentermine has been available for treating obesity since the 1950s, and is still the most widely prescribed weight loss therapy. Topiramate was approved in 1996 for treating epilepsy, and more recently as a prophylactic for migraine. The rationale behind Qnexa is to expand topiramate’s therapeutic window by using a very low dose and combining it with phentermine, which acts via a different mechanism. Topiramate works via GABA and other agonist properties and increases satiety, while phentermine is noradrenergic and non-serotonergic, and reduces appetite.

Status

Three pivotal phase 3 trials evaluating Qnexa in more than 4,500 patients were recently completed under a Special Protocol Assessment by the U.S. FDA.

EQUATE, the first of the three phase 3 studies, evaluated 756 obese subjects over 28 weeks at 32 sites.  EQUIP and CONQUER were 56-week studies; EQUIP evaluated 1,267 morbidity obese patients with or without co-morbidities and CONQUER evaluated 2,487 overweight and obese patients with at least two co-morbid condition. Completion rates up to 69% were significantly higher than placebo at all three doses of Qnexa, indicating favorable tolerability and a positive benefit/risk safety profile for Qnexa.

Chart coming soon

Clinical data from phase 2 and phase 3 trials with Qnexa demonstrate:

• Common side effects observed are expected and manageable
• Improved PHQ-9 and Quality of Life scores
• Significant improvements in cardiovascular, metabolic and inflammatory risk factors among patients treated with Qnexa;
• FDA efficacy benchmarks for weight loss agents exceeded at all three doses of Qnexa tested in the clinical program;
• Completion rates up to 69% were significantly higher than placebo at all three doses of Qnexa, indicating favorable tolerability; and
• Well tolerated, with a favorable benefit/risk safety profile for Qnexa
  

For full details please see the September 2009 press release and December 2008 press release.

Additionally, in December 2008, VIVUS announced an extension study to OB-303. This study will roll-over approximately 650 patients in a blinded fashion from OB-303, in order to provide two-year safety data.