(JM test 3)Adalimumab concentrations negatively linked to inflammatory markers in RA

A negative association exists between adalimumab (ADA) concentrations and markers of inflammatory disease activity in rheumatoid arthritis (RA), including interleukin 6 (IL-6), reveals a study. Notably, ADA concentrations from 5 to 7 mg/L over the dose interval seem to contribute to better disease control.

Overall, 156 people with RA (mean age 57.4 years, 69.2 percent female) received ADA for a minimum of 4 weeks. In multivariate analysis, lower ADA concentrations were associated with higher C-reactive protein (p<0.001) and higher weight (p<0.004) independently.

RA participants with Disease Activity Score in 28 joints (DAS28) ≤3.2 had higher ADA concentrations than those with DAS28 >3.2 (median 10.8 vs 7.1 mg/L; p<0.001). In addition, IL-6 showed a negative relationship with ADA concentrations (r, ‒0.04; p<0.01).

This cross-sectional study assessed the impact of patient characteristics and disease activity on ADA concentrations; explored the associations between ADA concentrations, antidrug antibody (ADAb) presence, and disease activity in RA; and examined the relationship between cytokine concentrations and ADA concentrations.

The authors assessed disease activity using the DAS28, with responders defined as DAS28 ≤3.2, and collected serum and plasma for ADA concentrations and ADAb, as well as a panel of cytokines for a subgroup. They compared ADA concentrations between demographic and clinical subgroups via ANOVA.

Additionally, a general linear model was used to analyse the independent associations between clinical and demographic features. Univariate and multivariate analyses were carried out to determine the variables with a significant association with ADA concentrations.