[Real-world evidence on the use of generic tofacitinib in patients with rheumatoid arthritis]

Objective: To describe the clinical outcomes of using generic tofacitinib in patients with rheumatoid arthritis (RA) who either initiated it de novo or underwent a non-medical switch from the original formulation. Methods: Retrospective cohort of adults with RA who either initiated generic tofacitinib (JANVAX®) or switched from original tofacitinib (XELJANZ®). Patients were followed until treatment discontinuation, death, or end of follow-up (12 months). Effectiveness was assessed using the DAS28-ESR scale via mixed-effects models. The switch group was evaluated at 0, 6, and 12 months; the initiation group at 0, 3, 6, and 12 months. The occurrence of adverse events was assessed for safety. Results: A total of 42 RA patients were included (24 in the switch group and 18 in the initiation group). Nine patients discontinued treatment. In the switch group, DAS28-ESR remained stable (2.96; 3.08; 3.10; p = 0.70). In the initiation group, improvement was significant (5.3, 3.42, 3.49, 3.31; p < 0.001). No major cardiovascular events (MACE) were reported. There was one death of unknown cause, three serious infections, one pulmonary embolism, and one diagnosis of malignancy during follow-up. Conclusions: The non-medical switch to generic tofacitinib and treatment initiation were associated with a good clinical response in terms of effectiveness, with no evidence of new safety concerns. However, the limited sample size calls for further studies to confirm these findings.