A study published December 7, 2011in the American Journal of Clinical Nutrition provides two-year data on the safety and effectiveness of Vivus Inc.’s drug candidate, Qnexa in patients with cardiometabolic disease.

Qnexa is a combination drug composed of phentermine and topiramate. It was tested in two doses among 676 subjects. Changes in weight were -1.8% for placebo, -9.3% for low dose and -10.5% for the high dose. Significantly more subjects at each dose achieved more than 5%, 10%, 15% and 20% weight loss compared to placebo. Subjects on the drug had improved cardiovascular and metabolic metrics and decreased rates of diabetes. The high dose was significantly better in weight loss among the most severely obese subjects. Adverse events were modest and drop-out rates were similar between placebo and drug groups. There were no deaths. There were two pregnancies. One was carried to term. The other resulted in a miscarriage. The infant was born with no observed birth defects which was a concern of the FDA Advisory Committee which reviewed the drug last year.Two-year sustained weight loss and metabolic benefits with controlled-release phentermine/topiramate in obese and overweight adults (SEQUEL): a randomized, placebo-controlled, phase 3 extension study 

The very impressive weight loss and low side effect profile from this two-year study are expected to improve the odds of approval by the FDA. Another Advisory Committee hearing in early 2012 is expected.