Sanofi-Aventis has decided to withdraw its application to market heart drug Multaq in Europe, after its knockback by the US Food and Drug Administration last week.

Multaq (dronedarone) had been submitted for approval as a new treatment for atrial fibrillation with the European Medicines Agency (EMEA). But Sanofi-Aventis decided to pull the filing after an EMEA advisory panel said that additional clinical data was needed that could not be provided within the current review period.

The news, while expected, is another setback for the company which slashed its profit forecasts last week, saying generic competition to its blockbuster blood thinner Plavix (clopidogrel) could substantially eat into the firm's profits. It also faces generic competition to its top-selling product Lovenox (enoxaparin), another blood thinner, and dronedarone had been billed as a new entrant that could in time reduce its reliance on these leading brands.

The French drugmaker does not expect to refile for Multaq in Europe until 2008, when it will have data from the ongoing ATHENA study to boost its application. Sanofi-Aventis has been asked to boost its recruitment into the study from 3,700 to 4,300 patients to boost its statistical power.

Last week, the FDA sent Sanofi-Aventis a ‘not-approvable’ letter for Multaq, also because the agency felt that more clinical evidence of the drug’s efficacy and safety was required.

WestLB analyst Oliver Kaemmerer said he had been expecting Multaq to bring in around 30 million euros in European sales this year, doubling to more than 60 million euros in 2007.

Plavix gets heart attack indication in Europe

However, there was better news for Sanofi-Aventis after the indications for Plavix were extended in Europe to include patients with a specific type of severe heart attack.

The EMEA authorised the drug for use in the treatment of patients with ST elevation acute myocardial infarction (STEMI) - a severe heart attack in which an artery supplying the heart with blood is generally totally blocked - who are eligible for anti-clotting therapy.