Infliximab dosing patterns in a sample of patients with Crohn's disease: results from a medical chart review.

BACKGROUND: Infliximab, a monoclonal antibody tumor necrosis factor-alpha inhibitor, is an effective therapy that is indicated for the treatment of patients with Crohn's disease. Although dose escalation from 5 mg/kg to 10 mg/kg is allowed according to the prescribing label of infliximab, conflicting results exist regarding the rate at which this escalation may occur, which may affect payers and providers.
OBJECTIVE: The goal of this exploratory study was to characterize and quantify the rate of infliximab dose escalation in a sample of patients with Crohn's disease.
METHODS: Administrative claims data from patients with Crohn's disease in a large mid-Atlantic managed care organization were collected and used to target and recruit providers into a chart review study of infliximab dosing. Data from the charts of 161 patients with Crohn's disease who were receiving infliximab between 2006 and 2010 were extracted. Patients were grouped into an infliximab dose-escalation group or a dose-stable group based on these data. The evidence of any infliximab dose ≥7.5 mg/kg or evidence of a mean maintenance interval of 42 days or less resulted in the placement of a patient in the dose-escalation group, with the balance of patients comprising the stable-dose group.
RESULTS: A total of 925 infliximab infusions were captured from 161 patients. Of the 161 patients identified, 110 had at least 4 infusions, and 4 had missing data; therefore, only 106 (66%) patients were qualified for the final infliximab dosing analysis. A total of 18 (17%) of these patients had evidence of infliximab dose escalation (dose-escalation group), and the remaining 88 (83%) patients had a consistent 5-mg/kg dose and schedule (stable-dose group). Of the 18 patients in the dose-escalation group, 9 (50%) had a decrease in maintenance interval, whereas 12 (66.7%) patients had an increase in their dosage. A total of 3 (16.7%) patients had both an increase in dose and a reduction in maintenance interval.
CONCLUSIONS: Infliximab has been shown to be a cost-effective treatment for patients with Crohn's disease. The rate of infliximab dose escalation in this study was within the lower range of published estimates for this medication. Studies using larger sample sizes are needed to validate the findings of the current study. In addition, studies that are focused on quantifying and describing the nature of infliximab dose escalation may be useful in the development of successful patient-treatment matching algorithms.