Baseline Anti-Citrullinated Protein Antibody Status and Response to Abatacept or Non-TNFi Biologic/Targeted-Synthetic DMARDs: US Observational Study of Patients with RA

Introduction Patients with rheumatoid arthritis (RA) may respond to treatments differently based on their underlying serology and biomarker status, but real-world data comparing treatment responses to abatacept versus other non-TNFi biologic or targeted-synthetic DMARDs by anti-citrullinated protein antibody (ACPA) status remain limited. We assessed the association between ACPA status and response to treatment in patients with RA. Methods Adults from CorEvitas’ RA Registry were identified who initiated abatacept, rituximab, tocilizumab, or tofacitinib, and had ACPA measured at/prior to treatment initiation and at the 6-month follow-up visit. Three cohorts were included: abatacept/rituximab (2006–2019), abatacept/tocilizumab (2010–2019), and abatacept/tofacitinib (2012–2019). Patient characteristics at initiation were compared by ACPA status (positive [+], anti-cyclic citrullinated peptide-2 [anti-CCP2] ≥ 20 U/ml; negative [−], anti-CCP2