Background/Purpose: Tofacitinib (TOFA), a targeted synthetic DMARD has recently appeared on the Canadian market. It is an oral agent, targeting the JAK 1 and JAK 3 subunits of the Janus Kinase pathway, indicated in the treatment of rheumatoid arthritis (RA). We describe here the experience that we have accumulated in the last four years on 131 patients.

Methods: The data of all patients with RA exposed to TOFA at the Institut de Recherche en Rhumatologie de Montréal and the Centre de l’Ostéoporose et de Rhumatologie de Québec either in monotherapy or in combination with other conventional synthetic DMARDs (csDMARDs) was extracted from the database. All patients’ data were obtained from the Rhumadata® clinical database and registry. Descriptive statistics include age, gender, diagnosis, previous and actual exposure to other csDMARDs and biologic agents, CDAI at the initiation of TOFA, duration of treatment, response to treatment, and the reason for ceasing therapy.

Results: The 131 patients exposed to TOFA since its launch were mostly female (82%), with a mean age and disease duration at treatment initiation of respectively 58.1 (11.8) and 11.5 (10.3) years. Most patients were rheumatoid factor positive (73%) and 47% ACPA positive. At the time of the analysis, 63% remained on treatment. Reasons for stopping are inefficacy (66%), adverse events (21%), infections (4%) and other/unknown (11%). Of all patients, 31% had previously been treated with csDMARDS only. Prior biologic agent exposure ranges from 1 to 9, and 62% had been exposed to less than five biologic agents. The 6, 12, 24 and 36 months’ retention rates of patients treated with tofacitinib were respectively 75.0 (SE=4.0), 65.4 (4.5), 54.7 (5.2), and 52.3 (47.7) percent. Subjects treated with and without methotrexate (MTX) had similar retention curves (see figure). Baseline CDAI for this subpopulation is 22.1 (SD=13.1) with improvements (decreases in CDAI) of 3.3 (SD=10.8) and 10.7 (SD=15.2) units from baseline for patients stopping and remaining on therapy respectively. At their last evaluation, 14.8%, of patients were in remission,  and 3.3%, 55.7% and 26.3% had low, moderate and high disease activity.

Conclusion: Patients treated with TOFA often had severe long-standing disease and had been exposed to numerous prior treatments, the majority being biologic agents. These patients show improvement in their disease activity score compared to baseline and the addition of MTX did not provide better sustainability over time.