OBJECTIVES: Adherence to biologic therapy remains a significant problem in the treatment of rheumatologic diseases. This study assessed persistence and adherence associated with certolizumab pegol (CZP), a biologic administered as a lyophilized powder (LYO) in-office or as a prefilled syringe (PFS) administered at home.

METHODS: Adult patients with ≥1 prescription for CZP from 2015Q1-2020Q1 (first CZP prescription = index date) and ≥1 diagnosis of axial spondyloarthritis (axSpA), psoriatic arthritis (PsA), or rheumatoid arthritis (RA) in the 12-months prior to the index date (baseline) were identified from the IBM® MarketScan® database. Patients without continuous eligibility during baseline were excluded. Patient baseline characteristics were summarized and compared by formulation. CZP persistence was calculated as the number of days from index date through the earliest of CZP discontinuation (beginning of a 90-day period without a CZP prescription), formulation switch, or end of eligibility. CZP adherence was calculated as the number of observed CZP claims divided by the number of expected CZP claims during the persistent period.

RESULTS: 4,014 (LYO=1,437; PFS=2,577) patients who initiated CZP following a diagnosis for axSpA, PsA, or RA were identified. Patients in the LYO cohort were older (mean age in years: LYO-55.33; PFS-47.39) with more comorbidities, including hypertension (LYO-50.03%; PFS-34.34%), hyperlipidemia (LYO-44.68%; PFS-30.66%), and chronic pulmonary disease (LYO-21.02%; PFS-17.15%). Prior to initiating CZP, 45.16% of the LYO cohort and 76.02% of the PFS cohort received other biologic therapies; adalimumab (44.56%) and etanercept (29.87%) were the most common across the cohorts. For both cohorts, median CZP persistence was ~9 months (LYO-281 days; PFS-286 days). More than three-quarters of patients had adherence ≥80% (LYO-77.45%; PFS-76.02%).

CONCLUSIONS: Most patients who initiated CZP for axSpA, PsA, or RA were adherent to either formulation of CZP.