Novartis has withdrawn its application in Europe to extend the labelling of its blockbuster cancer drug Glivec to include the treatment of aggressive systemic mastocytosis, a rare disease in which mast cells accumulate in tissues such as the bone marrow, days after winning approval in the USA.

The reason for the withdrawal was that a European Medicines Agency (EMEA) advisory committee said it did not have enough data to make a judgement on the benefit-risk balance of using Glivec (imatinib mesilate) in this setting.

Last week, the US Food and Drug Administration (FDA) included systemic mastocytosis as one of five additional indications approved for Glivec, which was already registered as a treatment for chronic myeloid leukaemia and gastrointestinal stromal tumours. The disease can lead to organ failure and usually has a poor long-term outcome.

The rarity of aggressive mastocytosos – the incidence is estimated at around 0.3 new cases per 100,00 of the general population – means that the impact of the decision on Glivec will be minimal. The drug saw its sales climb 20% to $653 million in the third quarter of 2006, and it is Novartis’ second-largest product by revenues.