UCB, will present a post hoc analysis of the EXXELERATE trial examining the efficacy of CIMZIA® (certolizumab pegol) and adalimumab in patients with rheumatoid arthritis (RA) with high rheumatoid factor (RF) levels. The data are being presented at the American College of Rheumatology (ACR) Convergence 2023 in San Diego, November 10?15. In the initial EXXELERATE trial comparing the efficacy of CIMZIA and adalimumab, the primary endpoints of superiority were not met.

In the post hoc analysis, efficacy outcomes in CIMZIA and adalimumab were assessed in patients with RA across RF subgroups. Patients were randomized 1:1 to CIMZIA 200 mg every two weeks plus methotrexate (MTX) or adalimumab 40 mg every two weeks plus MTX. At Week 12, patients were classified as responders or non-responders, non-responders were switched to the other TNFi with possible follow-up to Week 104. Results showed that for patients in the higher RF quartile, 65.7% of 453 patients treated with CIMZIA and 48.3% of 454 patients treated with adalimumab achieved low disease activity at Week 104.

RA is a chronic disease that causes inflammation throughout the body and commonly presents as joint pain, swelling, and deformity, which results in a decline in physical function and quality of life. It is estimated that, as of 2021, approximately 1.5 million people in the United States live with this disease. High RF is associated with a more aggressive and destructive disease course, which is often more difficult to treat.

One reason for this is the high levels of RF autoantibodies binding with the Fc parts of TNFis to form large immune complexes that are then degraded by macrophages, resulting in lower bioavailability of biologic drugs. To treat RA when high RF levels are present, American College of Rheumatology guidelines recommend biologic disease-modifying anti-rheumatic drugs (bDMARDS) if there is no observed improvement with MTX treatment. However, many bDMARDs such as TNFis contain an Fc region that RF antibodies bind to, which can result in a lower clinical efficacy and the need for additional interventions.

The distinctive, FC-free structure of CIMZIA means RF may not bind to the drug, allowing its concentration to remain stable over time.