Breakthrough in Hunt for Rheumatoid Arthritis Biomarkers

Researchers are significantly closer to establishing biomarkers that signal effective treatment of rheumatoid arthritis (RA).

An observational study demonstrated the meaningful impact of anti-cyclic citrullinated peptide (antiCCP) and Rheumatoid Factor (RF) status on patient response to treatment with abatacept (Orencia /Bristol-Myers Squibb).

The study — using data from the Corrona RA registry, the largest US observational cohort of rheumatoid arthritis patients,- was presented on June 9 at the Annual European Congress of Rheumatology in London, UK, by Leslie R. Harrold, MD, MPH, of the University of Massachusetts, Worcester, MA, and Corrona, LLC, Southborough, MA.

Analysis was performed on registry patients who had been tested for antiCCP and RF, and who had initiated therapy with either abatacept or a tumor necrosis factor alpha inhibitor (TNFi).

The study comprised 566 patients starting abatacept and 1715 TNFi users.

Measures of each participant’s Clinical Disease Activity Index were taken at or within six months of treatment and then re-assessed at six months post-treatment, with seroposivity defined as ≥20 U/mL for anti-CCP and ≥40 U/mL for RF.

The analysis demonstrated antiCCP/RF status influenced treatment response to abatacept initiators but not TNFi users.

Specifically, double positive (antiCCP+RF) patients on abatacept fared best versus the double negative group with both significantly improved disease activity scores and remission rates (ΔCDAI —8.9 vs –4.5, p=0.002; LDA 43% vs 26%, p=0.002; remission 15% vs 5%, p=0.001).

The results for single positive patients using abatacept demonstrated a greater likelihood of remission as compared to those with double negative status (12% vs 5%, p=0.018). While antiCCP status alone was found to correlate with improved outcomes, RF status alone did not produce statistically significant change.

The positive association demonstrated by the study reflects similar results found in an international cohort and, according to Harrold, represents an “exciting step toward the ability to tailor patients’ RA treatments — to deliver personalized medicine - in a manner that has been developing in the field of oncology.”

Additional studies are needed to discern longer term effects moving past the study’s six-month endpoint.

Harrold also anticipates that a follow-up observational study gauging the efficacy of ABA versus TNFi head-to-head will be published next year.