Safety of efalizumab in patients with psoriatic arthritis: results of a phase II, randomized, double-blind, placebo-controlled study

Abstract

Psoriatic arthritis (PsA) is an inflammatory arthritis associated with psoriasis that can lead to significant functional limitations. PsA an auto-reactive inflammatory disorder that is associated with a chronic T-helper cell response. The prevalence of PsA is estimated to range from 20% to 30% in patients with moderate to severe plaque psoriasis, and the etiology is believed to be similar to that of psoriasis. The efficacy and safety of efalizumab for the treatment of moderate to severe plaque psoriasis has been demonstrated in numerous Phase I, II and III clinical studies. Efalizumab, a humanized monoclonal IgG1 antibody, blocks T-cell-dependent functions mediated by leukocyte function-associated antigen-1 (LFA 1), blocking T-cell trafficking, T-cell activation, and adhesion of human T cells to antigen-presenting cells. In doing so, efalizumab inhibits secretion of tumor necrosis factor, a proinflammatory cytokine that is involved in both PsA and psoriasis.