* FDa asks co to remove contraindication for women of child-bearing potential
* Drug to remain contraindicated for pregnant women
* Shares up 18 pct in premarket trade (Adds details, background, share movement)
Jan 9 (Reuters) - Vivus Inc said the U.S. health regulator asked the company to remove a contraindication in the proposed label of its obesity drug Qnexa, a move that could help it reach a broader patient population.
The U.S. Food and Drug Administration asked Vivus to remove the Qnexa contraindication for women of child-bearing potential.
A contraindication means the drug should not be used in specific diseases or patient classes due to potential risks.
However, Qnexa will remain contraindicated for women who are pregnant.
The company is currently revising its proposed risk evaluation and mitigation strategy based on the change in the contraindication and plans to discuss details during an upcoming panel meeting.
Qnexa contains topiramate, which is used to treat migraine and epilepsy, and last month, data from a trial showed topiramate posed risks for pregnant women.
Vivus, which has faced multiple regulatory hurdles on Qnexa, had resubmitted a marketing application for the drug with a narrower indication that excludes women of childbearing potential, in October, a year after regulators rejected it and sought data to prove Qnexa did not increase heart risks.
Obesity, a leading cause of diabetes, heart disease and other serious health problems, has reached epidemic proportions in the United States with nearly a third of the population falling into the category.
Obesity drug developers Arena Pharmaceuticals, Orexigen Therapeutics and Vivus have hit several roadblocks in recent times as the FDA has set a high bar for treatments that are likely to be taken by a large number of people.
While Arena's lorcaserin has been connected to possible cancer risks, Orexigen's Contrave was sent back on heart safety concerns.
Vivus shares, which have gained 18 percent since the resubmission in October, were trading up another 18 percent at $12.04 before the bell. They closed at $10.16 on Friday on the Nasdaq.
Orexigen shares were up 6 percent in premarket trade, while Arena shares were down 2 percent. (Reporting by Esha Dey in Bangalore; Editing by Roshni Menon)