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US drugmaker Genzyme must complete a trial of its leukaemia drug Clolar before it can be approved for older patients, according the the US Food and Drug Administration (FDA).
Its oncology panel has ruled that the Massachusetts-based company must conduct a larger comparison study to prove its drug is safe and effective.
Clolar is already approved for relapsed or refractory acute lymphoblastic leukaemia (ALL) in patients under 21, and the company is seeking approval for adults over 60 who are too ill to undergo chemotherapy.
The FDA had previously asked Genzyme to conduct a randomised controlled study, but this was never done. Genzyme said that doctors were unwilling to put cancer patients on the alternative treatment recommended by the FDA.
Panellists said that without a comparison it was difficult to say whether patients would do better taking Clolar, a class of cancer medications known as purine nucleoside analogs, than other drugs already in use.
Says Dr Wyndham Wilson, of the National Cancer Institute: “It is unclear what group of folks would benefit most from this drug. In the absence of that, I would not want to see a change in standards without a randomised study.”
Copyright Press Association 2009
