Predictors of Joint Damage in Patients with Early Rheumatoid Arthritis Treated with High-dose Methotrexate with or Without Concomitant Infliximab: Results from the ASPIRE Trial

Objective: To identify disease characteristics leading to progression of joint damage in patients with early rheumatoid arthritis (RA) treated with methotrexate (MTX) versus those treated with infliximab plus MTX.

Methods: Patients who had not previously been treated with MTX with active RA were randomly assigned to receive escalating doses of MTX up to 20 mg/week plus placebo or infliximab at weeks 0, 2, and 6, and every 8 weeks thereafter through week 46. Radiographic joint damage was assessed using the modified Sharp/van der Heijde score (SHS). The relationship between disease activity measures at baseline and week 14, as well as those averaged over time, were examined in relation to the change in SHS from baseline through week 54.

Results: C-reactive protein (CRP) levels, erythrocyte sedimentation rate (ESR), and swollen joint count were associated with greater joint damage progression in the MTX-only group, while none of these parameters was associated with progression in the infliximab plus MTX group. Mean changes in SHS among patients in the highest CRP (> or = 3 mg/dl) and ESR (> or = 52 mm/hour) tertiles in the MTX-only group were 5.62 and 5.89, respectively, compared with 0.73 and 1.12 in the infliximab plus MTX group (P < 0.001). Patients with greater joint damage at baseline (SHS > or = 10.5) showed less progression with infliximab plus MTX compared with MTX alone (-0.39 versus 4.11; P < 0.001). Patients receiving MTX alone who had persistently active disease at week 14 showed greater radiographic progression of joint damage than those taking MTX plus infliximab.

Conclusion: High CRP level, high ESR, or persistent disease activity was associated with greater radiographic progression in the group taking MTX alone, while little radiographic progression was seen in patients receiving both MTX and infliximab, regardless of the abnormal levels of these traditional predictors.