Real-World Clinical Equivalence of Generic and Branded Tofacitinib: A Prospective Longitudinal Cohort Study in Patients With Rheumatoid Arthritis

Abstract

ObjectivesTo explore the clinical efficacy and safety of generic tofacitinib vs brand name tofacitinib in patients with rheumatoid arthritis (RA) in a single-center comparative study based on a prospective real-world cohort. MethodsPatients with RA receiving tofacitinib, either generic (Kelejia) or branded (Xeljanz), from March 2017, to December 31, 2022, were enrolled. The primary outcome was the simplified disease activity index (SDAI)–defined remission rate at month 6. Secondary outcomes included the rates of remission and low disease activity defined by other composite scores; European Alliance of Associations for Rheumatology response rate, and ultrasonic synovitis scores at months 1, 3, 6, and 12. Cost-effectiveness was investigated. Propensity score–based inverse probability of treatment weighting was adopted to reduce selection bias. ResultsA total of 204 patients were enrolled: 59 in the generic group and 145 in the branded group. An SDAI-defined remission was achieved in 41.1% and 39.2% of patients in the generic and branded groups, respectively, at month 6 (P=.85). Rates of remission and low disease activity achievement, changes in clinical disease activity scores, and power Doppler and gray scale synovitis scores at months 1, 3, 6, and 12 were comparable between the 2 groups. Similar proportions of patients in the groups achieved moderate/good response at months 1, 3, 6, and 12. Rates of drug retention and adverse effects were also similar in the 2 groups. Both Kelejia and Xeljanz were cost-effective, but Kelejia had a lower average cost-effectiveness ratio. ConclusionGeneric tofacitinib (Keljia) had equivalent clinical efficacy and safety and better cost-effectiveness compared with its originator (Xeljanz).