Initial Experience With Tofacitinib in Clinical Practice: Treatment Patterns and Costs of Tofacitinib Administered as Monotherapy or in Combination With Conventional Synthetic DMARDs in 2 US Health Care Claims Databases

Tofacitinib is an oral Janus kinase inhibitor indicated for the treatment of rheumatoid arthritis (RA). Tofacitinib can be administered as a monotherapy or in combination with conventional synthetic disease-modifying antirheumatic drugs (DMARDs). This study describes RA patients' characteristics, treatment patterns, and costs for those initiating tofacitinib treatment as monotherapy or combination therapy, using US claims data from clinical practice.A retrospective cohort analysis of patients aged ≥18 years with RA (International Classification of Diseases, Ninth Revision code 714.xx) and with ≥1 tofacitinib claim in the Truven Marketscan (TM) or the Optum Clinformatics (OC) database. Index was defined as the first tofacitinib fill date (November 2012-June 2014). Patients were continuously enrolled for ≥12 months before and after index. Adherence was assessed using the proportion of days covered (PDC) and medication possession ratio (MPR). Persistence was evaluated using a 1.5× days' supply gap or switch. All-cause and RA-related costs in the 12-month pre- and post-index periods were evaluated. Unadjusted and adjusted analyses were conducted on data on treatment patterns and costs stratified by monotherapy status.A total of 337 (TM) and 118 (OC) tofacitinib patients met the selection criteria; 52.2% (TM) and 50.8% (OC) received monotherapy and 83.7% (TM) and 76.3% (OC) had pre-index biologic DMARD experience. Twelve-month mean PDC values were 0.56 (TM) and 0.53 (OC), and 12-month mean MPR was 0.84 (TM) and 0.80 (OC), with persistence of 140.0 (TM) and 124.6 (OC) days. Between 12-month pre- and post-index periods, mean (SD) 12-month RA-related medical costs decreased by $5784 ($31,832) in TM and $6103 ($25,897) in OC (both, P0.05), whereas total costs increased by $3996 ($30,397) in TM (P0.05) and $1390 ($26,603) in OC. There were no significant differences in adherence, persistence, or all-cause/RA-related costs between monotherapy and combination therapy in unadjusted/adjusted analyses.This analysis adds to the existing tofacitinib knowledge base and will enable informed clinical and policy decision making based on valuable datasets independent of randomized controlled trials.