Biosimilars in rheumatoid arthritis in 2022 – data from the Romanian Registry of Rheumatic Diseases

Objective. The study aimed at determining whether RA patients starting or stopping biosimilars differ in any regard from those starting or stopping originals. Methods. Data on RA patients was obtained from the Romanian Registry of Rheumatic Diseases (RRBR) database between January 1st, 2022, and December 31st, 2022, encompassing all Romanian RA patients fulfilling the national criteria for bo/bsDMARD initiation, continuation or switching. Results. Etanercept and adalimumab predominated for initiations of biosimilars. Most entries on biosimilars originated from originals (including non-medical switches) and from bDMARDs without biosimilars. A historical effect of accumulation of patients was observed, manifested in the fact that originals still dominated the group of patients continuing their treatment, with the exception of infliximab, while biosimilars tended to be continued in younger patients and in patients with shorter disease duration. Cases categorized more severe by both patients, their doctors and their disease activity were preferably reserved for originals. In patients continuing their previous bDMARD, biosimilars exhibited higher DAS28 and SDAI remission rates. Conclusion. RRBR data from 2022 confirm the market rise of biosimilars in RA, but also physicians’ prudence in prescribing them to highly active cases. In the Romanian RA cohort, biosimilars are overall more effective in holding remission than originals.