Why carry out this study?

Improved knowledge of the relevant pathological processes in rheumatoid arthritis (RA) has led to the development of targeted therapies with differing mechanisms of action (MoAs), such as adalimumab and abatacept.

We aimed to provide new insights into the pharmacodynamic (PD) effects of treatment with abatacept versus adalimumab by profiling ACPAs and gene expression in patients from the AMPLE phase 3 clinical study.

What was learned from this study?

PD changes, as reflected by differing ACPA and gene expression profiles and immune cell signatures, observed after 2 years of abatacept or adalimumab treatment were consistent with the hypothesized MoAs of these agents; expression of genes related to activation of the immune system was lower with abatacept.

These findings illustrate how gene expression studies can provide potentially valuable information in addition to that gained from conventional clinical assessments, as they investigate underlying processes that are beyond the clinical manifestations of disease.

Further analysis of this data set from the AMPLE study is warranted and may provide valuable information regarding predictive biomarkers of response and disease progression.