Importance: The introduction of biological tumor necrosis factor inhibitors has improved the treatment of rheumatoid arthritis (RA) but at a substantial cost. These drugs have been shown to lead to superior radiological outcomes compared with a combination of conventional disease-modifying antirheumatic drugs over 2 years.
Objective: To investigate whether radiological superiority translates into better work loss outcomes.
Design, setting, and participants: Multicenter, 2-arm, parallel, randomized, active-controlled, open-label trial. Patients with early RA (symptom duration <1 year) were recruited from 15 rheumatology clinics in Sweden from October 1, 2002, through December 31, 2005. The study population was restricted to working-age patients (aged <63 years).
Interventions: Patients who did not achieve low disease activity after 3 to 4 months of methotrexate therapy were randomized to receive additional biological treatment with infliximab or conventional combination treatment with sulfasalazine plus hydroxychloroquine.
Main outcomes and measures: Monthly sick leave and disability pension days 21 months after randomization retrieved from the nationwide Swedish Social Insurance Office register. Main analyses were by intention to treat, including all patients, and adjusted for baseline sick leave and disability pension.
Results: Of 204 eligible patients, 105 were randomized to biological and 99 to conventional treatment. Seven patients in the biological and 4 in the conventional treatment group never received the study drug, and 72 and 52 patients, respectively, followed the study per protocol for 21 months. The baseline mean (SD) work loss was 17 (13) d/mo (median, 16 d/mo) in both groups (mean difference, 0.6 d/mo; 95% CI, -3.0 to 3.9). The mean changes in work loss at 21 months were -4.9 d/mo in the biological and -6.2 d/mo in the conventional treatment group (adjusted mean difference, 1.6 d/mo; 95% CI, -1.2 to 4.4). Including only patients receiving at least 1 dose of assigned treatment, the adjusted mean difference was 1.5 d/mo (95% CI, -1.5 to 4.4), and in per-protocol analysis the adjusted mean difference was 0.3 d/mo (95% CI, -2.8 to 3.8).
Conclusions and relevance: The radiological superiority of biological compared with conventional combination therapy did not translate into better work loss outcomes in patients with early RA who had experienced an insufficient response to methotrexate.
Trial registration: clinicaltrials.gov Identifier: NCT00764725.