Cyclosporine A versus methotrexate in the treatment of polymyositis and dermatomyositis.

Objective: To determine the effectiveness and tolerance of treatment with cyclosporine A (CyA) or methotrexate (MTX) added to corticosteroids in patients with severe, active polymyositis (PM) and dermatomyositis (DM).

Patients And Methods: Thirty-six patients (20 with DM, 16 with PM) were enrolled into the study and randomized in MTX (n = 17) and CyA (n = 19) groups. Muscle endurance and functional test (MEFT), clinical assessment (CA), global patient's assessment (GPA), muscle MRI, serum CK, myoglobin, IL-1Ra, and autoantibody status were used to assess the response to therapy after 1, 3, and 6 months.

Results: Significant improvement in MEFT, CA, GPA, and muscle MRI was found in both groups. Patients treated with MTX showed insignificantly better response than patients with CyA. CK levels in the MTX group decreased significantly after 1, 3, and 6 months, whereas a significant reduction in the CyA group was first observed after 6 months. IL-1Ra serum levels significantly dropped in the CyA group after two weeks, whereas in the MTX group the significant decrease was first seen after 3 months of treatment. Good correlation was found between each of the clinical parameters (MEFT, CA, and GPA), none of them showed any correlation with CK or IL-1Ra levels.

Conclusions: Administration of MTX or CyA added to corticosteroids was associated with clinical and laboratory improvement. Changes in CK and IL-1Ra levels were not associated with parameters of clinical disease severity measured in this study.