Vivus says obesity drug leads to 9 pct weight loss

LOS ANGELES Dec 11 (Reuters) - Drug developer Vivus Inc (VVUS.O) said on Thursday the first of three late-stage trials found that obese patients treated with the highest dose of its experimental drug Qnexa on average lost 9.2 percent of their weight.

Vivus said the 28-week, 756-patient study met its main goal of superior weight loss with two different doses of Qnexa, compared with the drug's individual components and a placebo pill. Patients in the placebo group on average lost 1.7 percent of their weight, while patients on "mid-dose" Qnexa lost 8.5 percent.

Qnexa is a combination of phentermine -- half of the recalled fen-phen diet pill -- and the epilepsy drug Topamax, or topiramate.

Timothy Morris, Vivus' chief financial officer, said weight loss results for the two components were also significantly better than placebo and will be disclosed on Friday at a meeting with analysts and investors.

Vivus said 66 percent of patients treated with full-dose Qnexa achieved weight loss of 5 percent or more.

The company said Qnexa was well-tolerated -- the most common side effects were itching, dry mouth, altered taste and constipation.

Reported drug-related adverse events for depression and altered mood were 1.9 percent for full-dose Qnexa, 0.9 percent for the mid-dose and 1.8 percent for placebo patients.

Patients in the trial were asked to restrict calories by 500 a day and advised to exercise three times a week.

Morris said Vivus expects results in mid-2009 from two larger Phase III trials of Qnexa and plans to file for U.S. Food and Drug Administration approval late next year.

He also said the company will begin to assess partnering opportunities once it has the data from the year-long studies in hand.

Vivus is also studying Qnexa as a treatment for diabetes, but Morris said the company needs to conduct a study of how the drug compares with phentermine and topiramate before it can launch a Phase III diabetes trial. (Reporting by Deena Beasley, editing by Matthew Lewis)