Efalizumab retreatment in patients with moderate to severe chronic plaque psoriasis.

Background: Efalizumab targets T cell-mediated steps important in psoriasis immunopathogenesis.

Objective: We sought to evaluate the efficacy and safety of efalizumab retreatment in patients with moderate to severe plaque psoriasis.

Methods: In this open-label, phase III study, 365 patients who received efalizumab therapy during an earlier clinical trial were retreated with 12 weeks of subcutaneous efalizumab (1 mg/kg/wk) 35 days or more after their last dose of efalizumab.

Results: After 12 weeks of efalizumab retreatment, 56.9% of patients achieved 50% or more improvement from baseline Psoriasis Area and Severity Index (PASI) and 25.3% achieved at least 75% reduction in PASI score. The mean percentage PASI improvement from baseline was 51.2%. Overall, 76.1% of patients surveyed were "very satisfied" or "satisfied" with the efficacy of efalizumab. The safety profile of efalizumab retreatment was similar to that observed in patients receiving efalizumab for the first time.

Limitations: Not all patients received sufficient exposure to efalizumab during their previous efalizumab clinical trial to allow for determination of their initial response to efalizumab. Of 365 patients enrolled in the study, 282 received at least 12 weeks of prior efalizumab therapy; of these patients, 208 (73.8%) achieved a PASI-50 response from their previous therapy.

Conclusion: These results suggest that retreatment with efalizumab therapy is an efficacious option for patients who have previously discontinued treatment.