The US Food and Drug Administration approved Bristol-Myers squibb’s Sprycel for patients with leukaemia yesterday, providing a new treatment option for the 30% of patients who do not achieve a response with the best-available treatment for these types of cancer.

The agency cleared Sprycel (dasatanib) for chronic myeloid leukaemia as well as Philadelphia-chromosome-positive acute lymphoblastic leukaemia in patients who do not respond to or cannot tolerate Novartis’ Gleevec/Glivec (imatinib), which has established itself as the ‘gold-standard’ therapy for CML.

"Sprycel offers an important alternative for patients with Ph+ ALL whose disease has not responded to or has stopped responding to other therapies," commented Steven Galson, director of FDA's Center for Drug Evaluation and Research. B-MS said it would make the new drug available across the USA in the next few days.

He also noted that although the long term benefits of Sprycel in CML are not yet known, early studies have suggested that B-MS’ drug may offer a significant improvement for many patients whose disease is resistant to other therapies.

“However, further data from ongoing studies are needed to evaluate whether Sprycel provides an actual clinical benefit in CML," said Galson.

Dasatanib was filed with European regulatory authorities in January of this year, and had been granted Orphan Drug designation for Ph+ ALL and CML indications in both Europe and the USA. Analysts have suggested it could achieve sales of around $500 million a year, potentially becoming a blockbuster product if its indications are expanded to include first-line treatment of leukaemia or other cancer indications. Novartis reported Gleevec sales of $2.2 billion last year.

The annual cost of Gleevec ranges from $32,000 a year for a 400mg daily dose to $64,000 a year for 800mg. Bristol-Myers said it would price Sprycel at $3,900 a month for its approved daily dose of 140mg, which equates to $47,000 a year.

US drug giant Pfizer is also developing a drug for patients resistant to Gleevec, but currently only for those with gastrointestinal stromal tumours (GIST). Sutent (sunitinib malate) received backing for approval by Europe's Committee for Medicinal Products for Human Use for this indication last month. Meanwhile, Novartis has another compound, Tasigna (nilotinib), with designs on the Gleevec non-responder segment, reporting positive data on this product earlier this month.