(Reuters) - Vivus Inc said the European regulator granted the U.S. company more time to prepare for an oral hearing of its diet drug Qnexa.

The oral hearing is now rescheduled to September. The regulator's opinion on the drug's marketing application is expected after the hearing.

Vivus said it is currently focusing on working with the U.S. Food and Drug Administration ahead of the July 17 review date, and expects the drug to be launched in the United States in the second half of the year.

Vivus's Qnexa is one of three experimental new weight loss drugs seeking approval from the FDA after initial rejections by the agency.

Arena Pharmaceuticals Inc and Orexigen Therapeutics have also tried to get their obesity pills approved but have been rejected.

(Reporting by Balaji Sridharan in Bangalore; Editing by Supriya Kurane)