ORAL TREATMENT OF ICHTHYOSIS BY THE CYTOCHROME-P-450 INHIBITOR LIAROZOLE

Liarozole, a novel imidazole derivative, inhibits the cytochrome P450- dependent 4-hydroxylation of retinoic acid, resulting in increased tis sue levels of retinoic acid. Twelve male patients with ichthyosis were given oral liarozole, 150 mg twice daily, in an open study for 12 wee ks, Immunohistochemical parameters of inflammation, epidermal prolifer ation and differentiation were assessed before and after treatment. Ex tent and severity of the skin lesions was markedly reduced in all pati ents. Clinical side-effects were reminiscent of those with synthetic r etinoids. No relevant changes were found in the haematological, urinar y and biochemical parameters. Immunohistochemical assessment showed a statistically significant induction of keratin 4 after liarozole treat ment in 10 of 12 patients. In two of these patients keratin 13 was ind uced. This open study showed that oral liarozole treatment was efficac ious and well tolerated in the treatment of different types of ichthyo sis. The immunohistochemical results suggest a retinoid mechanism as t he mode of action.