Background: Many patients with rheumatoid arthritis (RA) do not achieve adequate and safe responses with disease-modifying antirheumatic drugs (DMARDs). Tofacitinib is a novel, oral, Janus kinase inhibitor that treats RA.
Objective: To evaluate the efficacy and safety of tofacitinib in combination with nonbiologic DMARDs.
Design: 1-year, double-blind, randomized trial (ClinicalTrials.gov: NCT00856544).
Setting: 114 centers in 19 countries.
Patients: 792 patients with active RA despite nonbiologic DMARD therapy.
Intervention: Patients were randomly assigned 4:4:1:1 to oral tofacitinib, 5 mg or 10 mg twice daily, or placebo advanced to tofacitinib, 5 mg or 10 mg twice daily.
Measurements: Primary end points were 20% improvement in American College of Rheumatology (ACR20) criteria; Disease Activity Score for 28-joint counts based on the erythrocyte sedimentation rate (DAS28-4[ESR]) of less than 2.6; DAS28-4(ESR)-defined remission, change in Health Assessment Questionnaire Disability Index (HAQ-DI) score, and safety assessments.
Results: Mean treatment differences for ACR20 response rates (month 6) for the 5-mg and 10-mg tofacitinib groups compared with the combined placebo groups were 21.2% (95% CI, 12.2% to 30.3%; P < 0.001) and 25.8% (CI, 16.8% to 34.8%; P < 0.001), respectively. The HAQ-DI scores (month 3) and DAS28-4(ESR) less than 2.6 response rates (month 6) were also superior in the tofacitinib groups versus placebo. The incidence rates of serious adverse events for patients receiving 5-mg tofacitinib, 10-mg tofacitinib, or placebo were 6.9, 7.3, or 10.9 events per 100 patient-years of exposure, respectively. In the tofacitinib groups, 2 cases of tuberculosis, 2 cases of other opportunistic infections, 3 cardiovascular events, and 4 deaths occurred. Neutrophil counts decreased, hemoglobin and low- and high-density lipoprotein cholesterol levels increased, and serum creatinine levels had small increases in the tofacitinib groups.
Limitations: Placebo groups were smaller and of shorter duration. Patients received primarily methotrexate. The ability to assess drug combinations other than tofacitinib plus methotrexate was limited.
Conclusion: Tofacitinib improved disease control in patients with active RA despite treatment with nonbiologic DMARDs, primarily methotrexate.
Primary funding source: Pfizer.