Responses to Adalimumab in Patients with Active Psoriatic Arthritis Who Have Not Adequately Responded to Prior Therapy: Effectiveness and Safety Results From an Open-label Study

Objective. To evaluate the effectiveness and safety of adalimumab in patients with active psoriatic arthritis (PsA) and an inadequate response to prior therapy. Methods. Patients were treated with subcutaneous injections of adalimumab 40 mg every other week in addition to their standard antirheumatic therapies in a 12-week, open-label study. Effectiveness evaluations at Week 12 included American College of Rheumatology (ACR) and Psoriasis Area and Severity Index (PASI) response rates, Psoriatic Arthritis Response Criteria (PsARC), active dactylitis, enthesitis, and target lesion assessment. Physical function was evaluated using the Health Assessment Questionnaire Disability Index (HAQ-DI). Results. A total of 127 patients were enrolled. At Week 12, patients achieved ACR20, ACR50, and ACR70 response rates of 78.0%, 55.9%, and 21.3%, respectively. PASI50 and PASI75 response rates were 64.7% and 47.1%. A PsARC response was experienced by 70.1% of patients. Between baseline and Week 12. clinically and statistically significant reductions occurred in the mean total plaque score of the target lesion as well as in the percentages of patients with active dactylitis and enthesitis. A mean improvement in HAQ-DI was also observed (-0.44; p < 0.001). Three serious adverse events were reported, but none was considered related to adalimumab therapy. Conclusion. Adalimumab-treated patients achieved significant improvements in both skin and joint manifestations of PsA, as well as in physical function. Adalimumab was well tolerated and had a safety profile similar to that observed in other clinical trials of adalimumab for the treatment of PsA. ClinicalTrials.gov identifier: NCT00427362. (First Release July I 2010; J Rheumatol 2010; 37: 1898-906; doi:10.3899/jrheum.100069)