The US Food and Drug Administration has warned doctors only to prescribe two topical immunosuppressants, Novartis’ Elidel (pimecrolimus) and Fujisawa’s Protopic (tacrolimus), as directed and only after other eczema treatments have failed to work because of a potential increased risk of cancer associated with their use. The agency is also adding a “black box” warning to the products’ labels – the strongest available – and is developing a special medication guide for patients.

The FDA’s move comes as a result of recommendations made by its paediatric advisory committee last month, which said that tighter warnings should be added after reviewing cancer findings from animal studies [[17/02/05d]]. Data showed that the risk of cancer increased as the amount of drug increase, and that a small number of cancer cases were reported in children and adults treated with either Elidel or Protopic.

Both Novartis and Fujisawa have agreed to conduct research to determine whether there is an actual risk of cancer in humans and, if so, its extent.

Elidel and Protopic are both approved for short-term and intermittent treatment of atopic dermatitis (eczema) in patients unresponsive to, or intolerant of other treatments – but not children under two years of age, as they experienced a higher rate of upper respiratory infections in clinical trials than those treated with placebo cream [[14/12/01c]]. Protopic is expected to bring in 21.1 billion yen in sales this year – a 22% increase over the 17.3 billion yen generated last year – while Elidel generated sales of some $349 million in 2004 – up 49% [[21/01/05a]]. As their long-term safety is unknown, the FDA says that the products should be used only for short periods of time, not continuously, and patients should only use the minimum amount needed to control symptoms. Children and adults with a weakened or compromised immune system should not use Elidel or Protopic.