Safety of adalimumab biosimilar MSB11022 (acetate-buffered formulation) in patients with moderately-to-severely active rheumatoid arthritis.

OBJECTIVES: To compare the safety, efficacy, and immunogenicity of MSB11022 (acetate-buffered formulation), an adalimumab biosimilar, with the reference product. METHOD: AURIEL-RA study was a phase 3, multicenter, randomized, double-blind, parallel group trial (NCT03052322). Patients with moderately-to-severely active rheumatoid arthritis (RA) with an inadequate response to methotrexate were randomized 1:1 to MSB11022 or reference adalimumab. The primary endpoint was the incidence of treatment-emergent adverse events of special interest (AESIs) (predefined as hypersensitivity) up to week 52. The key secondary endpoint was ACR20 (≥ 20% improvement in American College of Rheumatology core set measurements from baseline) at week 12. Other efficacy endpoints, quality of life, immunogenicity, and pharmacokinetic parameters were evaluated up to week 52. Secondary safety endpoints were evaluated up to week 52 and at a 4-month safety follow-up. RESULTS: In total, 288 patients were randomized. The proportion of patients experiencing ≥ 1 treatment-emergent AESI up to week 52 was similar between trial arms: 6 patients (4.2%; 95% CI 1.56, 8.91) receiving MSB11022, and 8 patients (5.5%; 95% CI 2.41, 10.58) receiving reference adalimumab. No clinically meaningful differences in efficacy, quality of life, or immunogenicity were seen between treatment arms up to week 52. No notable difference in the incidence of treatment-emergent adverse events was observed between treatment arms up to the end of the follow-up period. CONCLUSIONS: These results suggest MSB11022 and reference adalimumab are similar in patients with moderately-to-severely active rheumatoid arthritis in terms of safety, immunogenicity, and efficacy. AURIEL-RA provides evidence to support the similarity of MSB11022 and adalimumab.Key Points• Incidences of hypersensitivity events were similar for MSB11022 (modified buffer) and reference adalimumab.• There was no difference in local reactions between MSB11022 (modified buffer) and reference adalimumab.• AURIEL-RA confirms the equivalence in efficacy and immunogenicity of MSB11022 (modified buffer) and reference adalimumab.