Some of the views expressed in the following notes on newly approved products should be regarded as preliminary, as there may have been limited published data at the time of publication, and little experience in Australia of their safety or efficacy. However, the Editorial Executive Committee believes that comments made in good faith at an early stage may still be of value. Before new drugs are prescribed, the Committee believes it is important that more detailed information is obtained from the manufacturer's approved product information, a drug information centre or some other appropriate source.
Neotigason (Roche Products)
10 mg and 25 mg capsules
Indication: severe psoriasis and keratinisation disorders
Acitretin is a metabolite of etretinate, an aromatic retinoid used in the treatment of severe psoriasis and keratinisation disorders. Vitamin A derivatives such as etretinate are teratogenic and pregnancy must be avoided. As the half life of etretinate is approximately 120 days, women treated with the drug are advised to avoid pregnancy for at least two years after discontinuing therapy.
Acitretin, which has been approved for the same indications as etretinate, has a life of only 54 hours. Therefore, theoretically, the risk period for teratogenesis is reduced. However, studies have discovered that the body can convert acitretin back into etretinate. Although the concentrations of etretinate generated during acitretin therapy are likely to be less than those found inpatients taking etretinate itself, the risk of teratogenesis remains. Therefore, women prescribed acitretin must also be advised to avoid pregnancy for two years after stopping treatment.
It is not known if acitretin has any clinical advantages over its parent compound. All the precautions associated with etretinate, e.g. monitoring of lipids and liver function, apply to acitretin.