To explore antinuclear autoantibody (ANA) and anti-double-stranded DNA (anti-dsDNA) autoantibody development during abatacept and tumour necrosis factor inhibitor (TNFi) treatment, and effects of switching from TNFi to abatacept in ANA/anti-dsDNA autoantibody-positive patients.
This was a post hoc analysis of biologic-naïve patients with active RA in ATTEST and AMPLE. In AMPLE, patients received subcutaneous abatacept or adalimumab (2 years). In ATTEST, patients received intravenous abatacept or infliximab (1 year), or placebo (6 months) then abatacept (6 months); at 1 year, all patients could receive abatacept (open-label long-term extension). Serum ANA/anti-dsDNA autoantibody levels were measured at baseline, Month 6 (ATTEST only), Years 1 and 2.
At baseline, 25.7 and 0.9% (AMPLE), and 21.6 and 8.4% of patients (ATTEST) were ANA/anti-dsDNA autoantibody positive, respectively. More baseline ANA/anti-dsDNA autoantibody-negative patients became positive during TNFi than abatacept treatment. In ATTEST (TNFi group), 48.5% (48/99; ANA) and 48.3% (57/118; anti-dsDNA) of patients seroconverted to positive status by Year 1, falling to 22.4% (22/98 ANA) and 13.3% (15/113; anti-dsDNA) by Year 2 after switching to abatacept. Of ANA/anti-dsDNA autoantibody-positive patients at Year 1, 41.9% and 68.9%, were negative at Year 2.
ANA/anti-dsDNA seroconversion was more frequent with TNFi than abatacept therapy; TNFi-associated seroconversion decreased after switching from TNFi to abatacept.