Abstract
Aim: Based on the benefit/risk profile of combination therapy with methotrexate (MTX) and Infliximab (IFX), a lower dosage of MTX might be preferable if IFX efficacy can be maintained.
Objectives: We evaluated whether MTX could be tapered to the minimum dosage (2 mg/week) in patients with rheumatoid arthritis (RA) who achieved adequate response to combination therapy. In addition, we evaluated whether adding low-dose tacrolimus (TAC) is efficacious for patients showing inadequate response to the therapy.
Method: Subjects comprised 51 RA patients who had received the combination therapy for ≥22 weeks. To analyze clinical response, disease activity score 28 using C-reactive protein (DAS28-CRP) was used to judge response to IFX. In patients with adequate response (DAS28≤3.2), MTX tapering was initiated by 2 mg every 8 weeks. In patients with inadequate response (DAS28＞3.2) to therapy at entry, TAC was added (maximum,2 mg/day).
Results: Thirty patients were enrolled and 21 patients (70%) with adequate response to therapy underwent reductions in MTX dosage. Sixteen of 21 patients maintained good response despites the mean dosage of MTX being reduced from 7.18 to 2.50 mg/week over 32 weeks. All patients with short disease duration (＜5 years) or with Steinbrocker class I could maintain good clinical response despite of MTX tapering. Nine inadequate-responders to IFX received added low-dose TAC, and clinical response improved in only 3 patients. Addition of low-dose TAC appears few efficacious.
Conclusion: Seventy six percent of the patients with adequate response to combination therapy with MTX and IFX achieved DAS28≤3.2 while reducing the mean MTX dose to 2.50 mg/week.
