U.S. advisers back first new diet pill in a decade

The first new weight-loss pill in a decade moved closer to U.S. approval on Tuesday, when a panel of expert advisers backed Orexigen Therapeutics's Contrave despite heart risk concerns.

It was the third new weight-loss drug to come before U.S. regulators this year, the Food and Drug Administration having rejected two rival medicines in October.

Orexigen's stock more than doubled to $12.20 from Monday's close of $4.76 when it reopened in after-hours trade Tuesday. Shares of competitors Vivus Inc and Arena Pharmaceuticals Inc also rose, as investors bet Contrave's approval could revive their fortunes.

The advisers were not overly impressed with the modest weight loss seen in patients taking Contrave, but some said rejection could quash development of such drugs at a time when two out of three Americans are overweight or obese.

"My concern is ... we will potentially kill development of these medications, and it is the most serious disease that the United States is facing," said panel chairman Abraham Thomas, head of endocrinology at Henry Ford Hospital in Detroit.

The outside experts voted 13-7 to back approval of Contrave but urged the FDA to require the company to conduct a larger clinical study to look at potential heart risks over time.

Contrave combines the alcohol and drug addiction drug naltrexone with the antidepressant bupropion in an attempt to boost metabolism while curbing appetite and cravings.

Study data showed a slight increase blood pressure and pulse rates for Contrave patients versus those given a placebo.

The pill met FDA effectiveness guidelines, in that at least 35 percent of patients studied lost at least 5 percent of their weight.

The FDA usually follows panel recommendations. A final ruling is due by January 31 but analysts said there could be a delay while post-marketing study details are agreed.

GOOD NEWS FOR RIVALS

Analysts said the panel vote was particularly good news for Vivus, the FDA having already asked for more data on heart risks of its Qnexa.

"This is great news for Vivus," said Ira Loss, who follows the FDA for Washington Analysis Corp. "The panel recommended a post-approval study and that tells me that will be the case for Vivus as well."

Shares of Vivus rose 12 percent in extended trading to $8.75 and shares of Arena, whose drug was rejected over cancers seen in animal studies, rose 10 percent.

The shares of all three companies have been volatile in recent months as their fortunes have shifted and investors swapped allegiance with each advisory meeting and FDA action.

The fate of Contrave is key to California-based Orexigen, which focuses solely on obesity drugs and has no products on the market so far.