FROM SEMINARS IN ARTHRITIS AND RHEUMATISM
Among adults with rheumatoid arthritis, serologic status regarding anti–cyclic citrullinated peptide (CCP) antibodies doesn’t appear to influence the effectiveness of tocilizumab therapy, according to a report published in Seminars in Arthritis and Rheumatism.
Compared with patients who have anti-CCP antibodies, those who don’t show differences in immune activation that may affect their response to various therapies. In particular, some experts have hypothesized that monoclonal antibodies such as tocilizumab that target the interleukin-6 receptor would be more effective in patients who are seronegative for anti-CCP antibodies than in those who are seropositive. Being able to predict patient response based on easily available biomarkers like CCP status would greatly assist treatment selection, said Laura C. Cappelli, MD, of the division of rheumatology at Johns Hopkins University, Baltimore, and her associates.
To examine this possibility, the investigators assessed 316 adults in an RA registry whose CCP status was available, who began taking tocilizumab during the 6-year study period, and who were followed up after 4-8 months for treatment response. Patients reported on pain, fatigue, and global disease activity, as well as on their general health using the modified Health Assessment Questionnaire (mHAQ). Their physicians reported on the number of tender and swollen joints in a 28-joint count and a global rating of RA severity, as well as determining the clinical disease activity index (CDAI) and the modified disease activity score (mDAS).
All but one of these eight measures of disease activity (the mHAQ) improved significantly with tocilizumab, regardless of patient anti-CCP status. In addition, the magnitude of change did not differ by anti-CCP status. These results persisted across several sensitivity analyses, Dr. Cappelli and her associates said (Semin Arthritis Rheum. 2017 Apr 1. doi: 10.1016/j.semarthrit.2017.03.024).
The findings indicate that CCP seronegativity does not improve the response to tocilizumab in this population derived from real-world patients at diverse clinical sites, the investigators noted.
This study was supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Dr. Cappelli and her associates reported having no relevant financial disclosures.
