Moreover, in an observational study of 566 patients with RA who received abatacept, and 1715 who received TNF-α inhibitors, anti-CCP-positive abatacept initiators were associated with significantly better treatment response than anti-CCP-negative abatacept initiators, but no significant difference was observed for TNF-α inhibitor initiators [11]. This evidence concerns the gene TNF and rheumatoid arthritis.