Anti-obesity drug on suicide watch

The new 'first in class' anti-obesity drug has been withdrawn from the US licencing process.

Sanofi-Aventis SA has withdrawn its application for rimonabant two weeks after an advisory panel said it should not be approved because it may increase suicidal thinking and depression.

Sanofi said it would work towards resubmitting the medicine, known by the brand names Acomplia and Zimulti, at a future date and would undertake necessary discussions with the Food and Drug Administration (FDA) on required modifications to its file.

The drug, which is already licensed in Europe, is also being monitored by the European Medicine's Agency's own regulatory committee. 'The review is expected to be finalized at the July CHMP (Committee for Medicinal Products for Human Use) meeting,' a spokeswoman for the European Medicines Agency told Reuters.

However, on 29 June, Sanofi-Aventis SA announced that it would be submitting an update of the safety data on 'psychiatric events' to the CHMP too.

Paul Diggle of Nomura Code Securities said the drug might yet have a future in the United States as a niche treatment for diabetes but as a weight-loss treatment it appeared 'fatally wounded'. He added: 'I don't think it will be withdrawn in Europe but I think the label is going to get tougher.'

Shaojing Tong, an analyst with Mehta Partners in New York, said the medicine could still be approved if it fares well in a large trial underway that may provide a better picture of its risks and benefits -- but this would delay approval until 2011. 'This trial is longer than earlier studies and metabolic benefits from raising HDL (good) cholesterol and lowering triglycerides could be reflected in terms of patient health benefits', Tong said.

The drug is the first in a new class of drugs that apparently switch off the same brain circuits that make people hungry when they smoke cannabis!