Orexigen, drug maker of Contrave, has announced a new trial for its obesity pill which it hopes to get to the market by 2014, pending regulatory approval.

The pills, which are undergoing review, are to be tested starting 2012. The trial aims to find out about the drug's cardiac risk profile, specifically - heart attacks. Should the drug be approved, it could be licensed by the FDA in 2014.

Health officials are worried over Contrave's cardiovascular risk profile, specifically whether it causes any heart defects.

In the 1990s, the obesity drug popularly known as fen-phen, a famous obesity drug was withdrawn after it was found to cause heart valve damage and pulmonary hypertension.

New obesity pills face increasingly tough measures - three prominent drugs Contrave, Qnexa and Lorquess were rejected initially - and look likely to face increasing restrictions over their safety and use. Qnexa raises concerns for pregnant women, and Lorquess has shown potential side effects in rats’ brains.

Story: Racing to Battle Obesity: Three Drugs Up for FDA Approval

The latest reports suggest that all three manufacturers will pursue further measures to avoid having their drugs rejected completely.

Jefferies & Co. analyst Thomas Wei cautioned on Wednesday about further announcements from drug makers Arena and Vivus, according to the Associated Press. The companies, which make Qnexa and Lorquess, respectively, may now need to make further study in order to reach Orexigen's level of standard, he said.

He estimated a further $100 million for Contrave to complete the trial which was suggested by the FDA.