Japanese firm Astellas yesterday retreated from its marketing alliance with Sanofi-Aventis for the embattled antibiotic Ketek (telithromycin), a decision that follows recent US Food and Drug Administration investigations into its safety. Sanofi-Aventis will, from October 1, market the drug alone in Japan.

Ketek was launched in December 2003 for treating various respiratory tract infections, including acute bronchitis and pneumonia, as well as tonsillitis, sinusitis and pharyngitis/laryngitis.

There was no mention as to why Astellas decided to back away from its alliance for Ketek, but the drug has come under increasing scrutiny in the USA and Europe. Most recently, Sanofi-Aventis suspended a clinical trial in children and - although it says it was unrelated to the safety issues raised - senior US politicians are saying it should never have been approved because of unanswered questions relating to its safety and efficacy, while the US Food and Drug Administration is considering changing the labelling after a review linked the drug to 12 cases of liver failure and four deaths. It is also under review in Europe.