Comparative multidatabase analysis of dosing patterns and infusion intervals for the first 12 infliximab infusions in patients with rheumatoid arthritis

Background: According to prescribing information for rheumatoid arthritis (RA) treatments in the United States, infliximab should be administered at weeks 1, 2, 6, and then every 8 weeks starting at a 3-mg/kg dose, with flexible dosing up to 10 mg/kg and/or every 4 weeks based on clinical response.

Objective: This study evaluated dosing and intervals of the first 12 infliximab infusions in patients with RA across multiple large administrative databases.

Methods: Data were obtained from 4 databases: HealthCore Integrated Research Database (HIRD), IMS LifeLink Health Plan Claims Database (IMS Lifelink), Premier Perspective Database (PPD), and Wolters Kluwer Pharma Solutions (WKPS). Patients were aged ≥18 years, diagnosed with RA, and naive to biologic therapy. Patients with other select inflammatory conditions were excluded. The induction period included infusions 1 through 3; the maintenance period included infusions 4 through 12.

Results: Observed dosing patterns from the HIRD, IMS LifeLink, PPD, and WKPS databases demonstrated minimal dose increases from the first infusion (93.5, 103.3, 58.8, and 73.2 mg, respectively) and from the first maintenance infusion (69.1, 64.3, 45.7, and 45.7 mg, respectively) to the highest dose during the first 12 infusions. The mean number of days between infusions in the maintenance period ranged from 53.3 to 63.5 in HIRD, 53.7 to 60.3 in IMS LifeLink, 53.4 to 59.4 in PPD, and 52.3 to 55.0 in the WKPS database.

Conclusion: Data from multiple databases of patients with RA suggest that, in clinical practice, infliximab dosing and intervals are consistent with FDA prescribing information and remain relatively stable during the first 12 infusions.