A European Union court has overturned a ban on a powerful class of anti-obesity drugs related to the popular "fen-phen" cocktail withdrawn from the U.S. market in 1997.

The European Union's Eexecutive Commission had outlawed the pills made by France's Laboratoires Servier two years ago, contending that chances of heart damage outweighed any weight-loss benefits.

Concern over the drugs containing dexfenfluramine and fenfluramine had been heightened by heart valve cases in Belgium, where patients used the drugs in combination with Chinese herbs.

Servier, which maintains that the drugs are safe if taken correctly, argued that the scientific assessment by the European Commission wasn't rigorous enough.

The court agreed that the commission lacked jurisdiction and ruled that Servier can conduct new trials and apply for permission to market the drugs in the various member states.

The European Commission said it will appeal the decision to the European Court of Justice, and will ask the Court of Justice to block any sale of the drugs until it decides on the appeal.

Other sources: British Media