Pharmacological profile and clinical effect of tacrolimus ointment (Protopic ointment) for atopic dermatitis]

Atopic dermatitis (AD) is thought to be induced by a complex of various allergic reactions and T cells are implicated in its etiology. Since tacrolimus strongly inhibits T cell activation, tacrolimus ointment has been developed as a novel drug for AD throughout the world. Tacrolimus inhibits mast cell and eosinophil activation and antigen presenting activity of Langerhans cells in vitro. In the in vivo experimental animal models of AD, such as contact and spontaneous dermatitis in mice and repeated hapten treated skin inflammation in rats, tacrolimus ointment showed inhibitory activity. In clinical studies with AD patients in Japan, USA and Europe, tacrolimus ointment showed a marked effect. In comparative studies in Japan, it showed the same efficacy as a strong class steroid ointment on eczema at the trunk and extremities and superior efficacy at the face and neck compared to a medium class steroid. The most prominent adverse event is experienced at the local application site with reactions such as a burning sensation and erythema. Systemic side effects were rarely observed. While there is a possibility of skin infections when using tacrolimus, skin atrophy, even after long term treatment, was not observed. Thus tacrolimus ointment could be an efficient alternative to steroid ointment for AD.