Long-Term Durability of Certolizumab Pegol in Patients with Rheumatoid Arthritis Over 5 Years: An Analysis of Pooled Clinical Trial Data

Introduction: There is a paucity of data on how patient characteristics may affect the long-term durability of certolizumab pegol (CZP) in patients with rheumatoid arthritis (RA). This study therefore aimed to investigate CZP durability and reasons for discontinuation over 5 years between different subgroups of patients with RA. Methods: Data were pooled from 27 clinical trials in RA patients. Durability was defined as the percentage of patients randomized to CZP at baseline who were still on CZP treatment at a given timepoint. Post hoc analyses of clinical trial data on CZP durability and reasons for discontinuation among different patient subgroups were conducted using Kaplan-Meier curves and Cox proportional hazards modeling. Patient subgroups included: age (18- < 45/45- < 65/ >= 65 years), gender (male/female), prior tumor necrosis factor inhibitor (TNFi) use (yes/no), and disease duration (< 1/1- < 5/5- < 10/ >= 10 years). Results: Among 6927 patients, the durability of CZP was 39.7% at 5 years. Patients aged >= 65 years had a 33% greater risk of CZP discontinuation than patients 18- < 45 years (hazard ratio [95% confidence interval]: 1.33 [1.19-1.49]) and patients with prior TNFi use had a 24% greater risk of discontinuing CZP than patients without (1.24 [1.12-1.37]). Conversely, greater durability was observed among patients who had a baseline disease duration of >= 1 year. Durability did not differ in the gender subgroup. Of the 6927 patients, the most common reason for discontinuation was inadequate levels of efficacy (13.5%); followed by adverse events (11.9%); consent withdrawn (6.7%); lost to follow-up (1.8%); protocol violation (1.7%); other reasons (9.3%). Conclusions: CZP durability was comparable with durability data on other bDMARDs in RA patients. Patient characteristics that were associated with greater durability included younger age, TNFi-naivety, and disease duration >= 1 year. Findings may be helpful in informing clinicians on a patient's likelihood of discontinuing CZP, based on their baseline characteristics.