@article {Nabie002560, author = {Hafsah Nabi and Oliver Hendricks and Dorte Vendelbo Jensen and Anne Gitte Loft and Jens Kristian Pedersen and S{\o}ren Andreas Just and Kamilla Danebod and Heidi Lausten Munk and Salome Kristensen and Natalia Manilo and Ada Colic and Asta Linauskas and Pia H{\o}ger Thygesen and Louise Brot Christensen and Maren H{\o}gberget Kalisz and Niels Lomborg and Stavros Chrysidis and Johnny Lillelund Raun and Marlene Andersen and Frank Mehnert and Niels Steen Krogh and Merete Lund Hetland and Bente Glintborg}, title = {Infliximab biosimilar-to-biosimilar switching in patients with inflammatory rheumatic disease: clinical outcomes in real-world patients from the DANBIO registry}, volume = {8}, number = {2}, elocation-id = {e002560}, year = {2022}, doi = {10.1136/rmdopen-2022-002560}, publisher = {BMJ Specialist Journals}, abstract = {Objective Successful uptake of biosimilars in rheumatology is limited by lack of real-world evidence regarding effectiveness of biosimilar-to-biosimilar switching. We investigated infliximab biosimilars CT-P13-to-GP1111 switching among patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA).Methods Observational cohort study from the DANBIO registry. Patients were classified as originator-na{\"\i}ve or originator-experienced. Retention rates of 1-year GP1111 treatment were explored (Kaplan-Meier). We identified baseline factors (at the time of switch) associated with withdrawal of GP1111 (multivariable Cox-regression analyses with HRs including originator treatment history). Changes in subjective and objective measures of disease activity 4 months before and after the switch were assessed in individual patients.Results Of 1605 patients (685 RA, 314 PsA and 606 AxSpA, median disease duration was 9 years, 37\% in Clinical Disease Activity Index/Ankylosing Spondylitis Disease Activity Score remission), 1171 were originator-na{\"\i}ve. Retention rates at 1-year were 83\% (95\% CI: 81\% to 85\%) and 92\% (95\% CI: 90\% to 95\%) for the originator-na{\"\i}ve and originator-experienced, respectively. GP1111 retention rates were higher in originator-experienced compared to originator-na{\"\i}ve with RA (HR=0.4 (95\% CI: 0.2 to 0.7)) and PsA (HR=0.2 (95\% CI: 0.1 to 0.8)), but not significantly for AxSpA: HR=0.6 (95\% CI: 0.3 to 1.2). Lower disease activity was associated with higher retention. Changes in disease activity preswitch and postswitch were close to zero.Conclusion This real-world observational study of more than 1600 patients with inflammatory arthritis showed high 1-year retention following a nationwide infliximab biosimilar-to-biosimilar switch. Retention was higher in originator-experienced and in patients with low disease activity, suggesting outcomes to be affected by patient-related rather than drug-related factors.Data are available upon reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information.}, URL = {https://rmdopen.bmj.com/content/8/2/e002560}, eprint = {https://rmdopen.bmj.com/content/8/2/e002560.full.pdf}, journal = {RMD Open} }