Arena Pharmaceuticals Inc. announced today that its experimental pill against obesity passed a test showing it does not damage heart valve like the Wyeth combination treatment, which consisted of fenfluramine and phentermine. The latter was withdrawn from the market in September 1997, after reports of valvular heart disease and pulmonary hypertension.

After tracking 3,200 patients involved in the experiment for one year, specialists discovered Arena’s product presented no risks for the heart. An independent Echocardiographic Data Safety Monitoring Board declared the drug was safe and the trial could be continued. The effectiveness results of the trial will be revealed within another year.

"We believe that this exposure duration, even under a conservative interpretation of the literature, would have been sufficient to observe a fenfluramine like effect on heart valves if present," said Jack Lief, Arena's president and chief executive in a statement, according to CNN Money.

The drug used by Arena Pharmaceuticals, lorcaserin, stimulates a protein in the brain that makes people feel full. On the other side, the drug has a minimal effect on a different brain receptor that could have caused heart valve disease in the case of fen-phen combination.

A previous study of Lorcaserin, which lasted only three months, showed that people who took lorcaserin lost about eight pounds at three months, while patients who were taking placebo pills only lost one pound or less.

According to the Centers of Disease Control and Prevention, more than 30 percent of the American population suffers from obesity, a condition which leads to many problems and diseases, increasing morbidity and mortality.

Lorcaserin will enter the market in 2010. As Arena holds all the rights to lorcaserin, it doesn’t hurry to sign a partnership with companies interested in the product. The drug-maker thinks it will receive many partnering offers after the last year of trial which will prove the drug’s safety and effectiveness.