Clinical outcomes of switching to adalimumab biosimilar (MSB11022) in patients with rheumatoid arthritis: RESTART Spanish Registry.

MSB11022 is a biosimilar of adalimumab that has been shown comparable bioequivalence, safety, tolerability, and immunogenicity profiles to the reference adalimumab in healthy volunteers or in patients with psoriasis or rheumatoid arthritis (RA). This is the first study conducted under clinical practice conditions evaluating the switch from reference adalimumab to MSB11022 in patients with RA. Retrospective and multicenter study with data from the medical records of patients with RA who switched from reference adalimumab or another biosimilar to MSB11022 and maintained this treatment for at least 6 months. Information registered comes from baseline visit, the moment of the switch, and the follow-up visits. Data from 86 patients were evaluated (median age 63.5 years, 75.6% female, 44.2% had erosive RA). Only 3.5% of the patients received biologic therapy prior to adalimumab. At baseline, median DAS28-CRP was 1.77 (80.2% in remission and 96.5% with low disease activity) and median CDAI was 4.00 (44.2% in remission and 90.7% with low disease activity). After a median follow-up of 8 months, median DAS28-CRP was 1.87 (86.0% in remission and 94.2% with low disease activity) and median CDAI was 4.00 (38.5% in remission and 95.3% with low disease activity). Only three patients experienced pain, swelling, and stinging at the injection site or a locally extensive hematoma in the area of administration. Adalimumab biosimilar MSB11022 maintained the efficacy benefits provided by previous adalimumab treatments with a safety profile in line with that already described for other biosimilars.