New Weight-Loss Drug Shows Heavy Promise

An experimental weight-loss drug produced by Vivus, Incorporated recently met U.S. guidelines in two late-stage trials. The proven effectiveness of the new obesity drug, known as Qnexa, has paved the way for Vivus to seek regulatory approval from the U.S. Food and Drug Administration (FDA).

The studies included more than 3,750 patients taking one of three doses of Qnexa or a placebo. During each 56-week analysis, researchers tracked the percentage of participants who lost 5 percent of their body weight. Those participants who received Qnexa enjoyed 67 percent and 70 percent success rates, while participants who received placebo attained only 17 percent and 21 percent success rates. Even more impressive was that one particular group achieved an average weight loss of 14.7 percent.

Study participants who received a placebo adhered to a low-calorie diet and lost an average of 6 pounds after one year. In one study, called Equip, participants receiving the highest dose of Qnexa had an average weight loss of 18 pounds by the end of the trial. During the other study, named Conquer, individuals taking the higher dose of Qnexa had lost an average of 30 pounds by the trial’s end.

The studies also indicated that Qnexa could offer some added benefits. In a statement, Vivus noted that patients taking the drug showed “significant improvements” in cardiovascular and metabolic risk factors, including blood pressure, cholesterol levels, and type 2 diabetes. Qnexa is a combination drug that mixes a generic form of the commonly prescribed appetite suppressant phentermine, and a generic form of the anticonvulsant drug topiramate, which is used in the treatment of epilepsy and migraine headaches.

In a telephone interview, Leland Wilson, president and chief of staff at Vivus, stated, “We would market this drug to people with significant obesity and co-morbidities.” He then added, “This is serious medicine for those with serious disease.” Wilson also pointed out that the trials “demonstrated remarkable safety.”

Vivus is racing against competitors Orexigen Therapeutics, Incorporated and Arena Pharmaceuticals, Incorporated to begin marketing a new weight-loss drug in the U.S. Based on the successful results of the later-stage trials, Vivus plans to request FDA approval by the end of 2009. This could very well put the Vivus application ahead of Orexigen’s for their new drug, known as Contrave32. This drug met key weight-loss goals in three late-stage trials, which prompted the company to plan for seeking FDA approval in early 2010.

However, Arena Pharmaceuticals may actually be the first of the three companies to apply to the FDA for approval for its new obesity drug, called lorcaserin, late this year. The company plans to release the results of its second late-stage study this month. To date, studies on lorcaserin have demonstrated that the drug is well tolerated by patients and that it offers a 48 percent weight-loss success rate for loss of more than 5 percent of total body weight.

According to the Centers for Disease Control and Prevention an estimated 32 percent of American adults are obese and the rate is expected to increase. In addition, the World Health Organization projects that global obesity levels will increase by 75 percent to include a total of 700 million people by 2015.