Background Leflunomide is a new disease-modifying antirheumatic drug (DMARD) approved for the treatment of active RA as an alternative to methotrexate (MTX) therapy. Infliximab is approved for the treatment of RA when used in combination with MTX. However, in patients either intolerant of or refractory to MTX therapy, combination therapy with leflunomide is sometimes utilised.

Objectives To assess the efficacy and safety of infliximab plus leflunomide in patients with RA.

Methods Select community practices were surveyed about the use of infliximab in combination with leflunomide for the treatment of RA. Demographic data and information on prior and concomitant medications were documented. Further data regarding efficacy (numbers of swollen and tender joints, functional class, ESR/CRP) and safety (occurrence of nausea, vomiting, alopecia, or any other symptoms) are being collected at baseline (prior to start of the combination) and after 4 to 5 doses of the combination.

Results Twenty-one community practices were included in the survey; 31 patients were identified who recently started on the combination of infliximab plus leflunomide. The patient population consisted of 20 (65%) women and 11 (35%) men. Patients ranged in age from 29 to 80 yrs (mean of 56.3 yrs). The duration of RA ranged from 2 to 50 yrs (mean of 10.6 yrs). Twenty-six (84%) patients had received MTX at a mean dose of 18.2 mg/wk. 42% of the population developed intolerance to MTX. MTX was ineffective in 45% of patients and contraindicated in 16% of patients. Patients were generally started on leflunomide at 20 mg QD. Rheumatologists added infliximab (3 mg/kg q 8 wks after loading doses at Weeks 0, 2, and 6 in the majority of patients) due to an incomplete response achieved with leflunomide. 71% of these patients also continued to receive concomitant prednisone at 2.5 to 20 mg/day. While patients had only received a few doses each, no serious adverse experiences were reported. This population will continue to be followed over time for both safety and efficacy of the infliximab/leflunomide combination.

Conclusion Infliximab has been used in combination with leflunomide in select RA patients in whom MTX has not been tolerated, is ineffective, or is contraindicated. The ongoing clinical experience of these and similar patients will be monitored.