Abstract
Background Psoriasis is a chronic, relapsing skin disease that may require multiple treatment courses. Alefacept targets the memory T cells implicated in psoriasis pathogenesis. This open‐label study evaluated the safety and tolerability, efficacy, and pharmacodynamics of repeat courses of alefacept in men and women with chronic plaque psoriasis. This article reports the interim results of this ongoing study.
Methods Patients (n = 174) who participated in previous phase II studies of alefacept were included in this retreatment study. Intravenous alefacept (7.5 mg) was administered once weekly for 12 weeks followed by 12 weeks of observation. Initial and subsequent retreatment courses were only given when, in the opinion of the investigators, disease had returned and necessitated treatment; CD4^+^ T‐cell counts had to be at or above the lower limit of normal.
Results Adverse events were similar regardless of the retreatment course. No opportunistic infections, rebound of disease, or flares were reported. Low titers of anti‐alefacept antibodies occurred in a few patients without related safety issues. Sixty‐six per cent of patients achieved a ≥ 50% reduction in the Psoriasis Area and Severity Index (PASI) at any time after the first dose of retreatment course 1. Patients who received two retreatment courses (n = 50) had consistent or improved responses after the second course; 64% and 68% of these patients achieved a ≥ 50% PASI improvement at any time after the first dose of retreatment courses 1 and 2, respectively. Alefacept selectively reduced memory T cells without cumulative effects.
Conclusions Repeat courses of alefacept were well tolerated, and subsequent retreatment courses were at least as effective as the initial course of therapy.