Alefacept: potential new therapy for patients with moderate-to-severe psoriasis.

Alefacept is a new biotechnology product designed for the treatment of patients with chronic plaque-type psoriasis who have disease severe enough to make them eligible for phototherapy or systemic therapy. In two randomized controlled phase III trials of patients with moderate-to-severe disease, alefacept showed a modest but statistically significant increase in the number of responders compared to placebo. Alefacept's dose-dependent CD4+ T lymphocyte-depleting effect requires monitoring; however, no association has been found between this adverse effect and serious adverse events, particularly infection. Due to lack of direct comparative data, it is difficult to predict exactly how alefacept will fit into the current rotational psoriasis therapy paradigm.