Advances in immunotherapy for psoriasis

Over the past 20 years it has become accepted that psoriasis is a T-cell-mediated, probably autoimmune disease. Initial observations that ciclosporin is an effective therapy for psoriasis helped substantiate the T-cell-mediated hypothesis. The development of new selective targeted immunotherapies for psoriasis have not only provided new therapies but in addition have helped dissect the key pathways in this disease. The new biological therapies fall into 2 categories - T cell targeting and cytokine modulation. Examples of the former include an LFA-3 fusion protein (alefacept) and anti-CD11a (efalizamab). Cytokine modulation includes: inhibition of proinflammatory cytokines such as tumour necrosis factor-α e.g. infliximab and etanercept; and cytokine switching by administration of Th 2 cytokines such as interleukin-10. The introduction of biological therapies will undoubtedly broaden our armamentarium for psoriasis treatment and perhaps, with their specificity of action, may allow identification of disease subsets.