Objective: To evaluate the efficacy and safety of alefacept in combination with methotrexate (MTX) for the treatment of psoriatic arthritis (PsA).
Methods: Patients were eligible for this randomized, double-blind, placebo-controlled trial if they were ages 18-70 years and had active PsA (> or = 3 swollen joints and > or = 3 tender joints) despite treatment with MTX for > or = 3 months (a stable dosage for > or = 4 weeks prior to enrollment). Patients were stratified according to psoriasis body surface area (BSA) involvement (> or = 3% or < 3%). Alefacept (15 mg) or placebo was administered intramuscularly once weekly for 12 weeks in combination with MTX, followed by 12 weeks of observation during which only MTX treatment was continued. The primary efficacy end point was the proportion of patients achieving a 20% improvement in disease activity according to the American College of Rheumatology criteria (an ACR20 response) at week 24.
Results: One hundred eighty-five patients were randomly assigned to receive alefacept plus MTX (n = 123) or placebo plus MTX (n = 62). At week 24, 54% of patients in the alefacept plus MTX group achieved an ACR20 response, compared with 23% of patients in the placebo plus MTX group (P < 0.001). Mean reductions in tender and swollen joint counts in patients receiving alefacept plus MTX were -8.0 and -6.3, respectively. In patients with psoriasis involving > or = 3% BSA (n = 87), a 50% reduction from the baseline Psoriasis Area Severity Index at week 14 was achieved by 53% of patients receiving alefacept plus MTX compared with 17% of those receiving placebo plus MTX (P < 0.001). Most adverse events were mild to moderate in severity. In the alefacept plus MTX group, the incidence of serious adverse events was low (1.6%), and no opportunistic infections or malignancies were reported.
Conclusion: Alefacept in combination with MTX may be an effective and safe treatment for PsA.