(Reuters) – shares of Vivus doubled in Premarket operations, a day after the pill to lose weight the laboratory received a favorable review of a U.S. regulatory panel, causing at least two brokerages to increase their stock price target.

On Wednesday, a panel of the administration of food and drugs ( FDA for its acronym in English) United States decided by 20 votes in favour and 2 against the approval to market the drug against obesity, raising the expectations of other two rival drugs.

“In our opinion, the resounding vote of confidence of the FDA Advisory Committee gives us hope that Qnexa will be adopted for the (revised) date of April 17”, said Jason Butler, of JMP Securities, almost tripling its forecast of price to $45.

Qnexa from Vivus Inc, competes with lorcaserin’s Arena Pharmaceuticals Inc. and Contrave from Orexigen Therapeutics Inc.

“However, we remain cautious and believe that the FDA could even require a test of cardiovascular safety prior to the approval of Qnexa and all potential drugs for obesity,” said analyst Thomas Wei Jefferies in a note to its clients.

Wei raised its forecast of price of the shares of Vivus of 3 to 11 $.

Shares of the company based in Mountain View, California, operated 22,80 dollars on Thursday. On Wednesday closed the Nasdaq to $ 10.55.

Qnexa could be used to treat obesity and the health problems that generates disease.

(Report by Vidya P L Nathan in Bangalore)