A study has claimed that the weight loss drug Meridia increases heart risks, prompting renewed calls by consumer advocates for the drug to be taken off the market.

Final data from the so-called SCOUT study, which was funded by Abbott Laboratories, offered detailed evidence showing that Meridia increases the risk of heart attacks and strokes in patients who already have heart disease. Patients taking the drug lost an average of 8.8 pounds (4 kg).

Patients given Meridia had a 16% increased risk of heart problems such as heart attack or stroke compared to those given a placebo, the study showed. There was no increased risk of death, although Meridia patients also saw an increase in blood pressure and heart rate.

The findings come two weeks ahead of a U.S Food and Drug Administration public hearing to discuss whether to take further action against the drug, which has already been withdrawn in Europe.

"When you put those things together, you have to wonder if the drug should be on the market any longer," Dr. Gregory Curfman, executive director of the New England Journal of Medicine which published the study, said.

"That's what you're trying to prevent through weight loss. You're trying to prevent people from having heart attacks, and here this drug caused more."

Preliminary results from Abbott's study were initially disclosed to both U.S and European health officials in late 2009 and led to Meridia's removal from the European market. At the same time, the FDA strengthened the drug's warning about risks to patients with pre-existing cardiovascular disease and called for a public meeting with its outside advisers. An FDA advisory panel is to meet on September 15 to discuss the drug.