Table 2

Frequency of anti-ADA antibodies and clinical response (ΔDAS28) after 28 weeks of adalimumab treatment

Total population (N = 235)Anti-TNF naive patients (n=183)IFX switchers (n=52)IFX switchers with anti-IFX (n=33)IFX switchers without anti-IFX (n=19)
Anti-ADA status, n (%)46 (20)32 (18)14 (27)11 (33)3 (16)
ΔDAS28 all1.6±1.51.7±1.51.1±1.41.2±1.30.9±1.4
ΔDAS28 anti-ADA−1.8±1.4*2.0±1.4*1.3±1.3*1.6±1.1*0.9±1.4NS
ΔDAS28 anti-ADA+0.6±1.30.6±1.30.5±1.40.4±1.40.7±1.4
  • Results are shown as n (%) or mean±SD.

  • Anti-adalimumab status could not be determined in two of the anti-TNF naive patients owing to missing serum samples. The difference in ΔDAS28 between anti-adalimumab-negative (anti-ADA−) and -positive (anti-ADA+) patients was significant for the total population* (p=0.000), anti-TNF naive patients*, switchers* and infliximab (IFX) switchers with anti-infliximab (anti-IFX)* (p≤ 0.05). The difference in ΔDAS28 between anti-adalimumab-positive and -negative patients did not reach significance in infliximab switchers without anti-infliximab (p=0.809).

  • ADA, adalimumab, DAS28, Disease Activity Score in 28 joints; IFX, infliximab.