Effectiveness of risk management plans: a case study of pemoline using pharmacy claims data

To assess the effectiveness of a pharmaceutical risk management plan using pemoline as a case study and pharmacy claims as the data source.

Prescription claims from a continuously enrolled US population (September 1, 2000-September 30, 2002) from Caremark, a pharmacy benefit manager, were evaluated for patients with one or more pemoline claims. Patients were categorized using pemoline as second-line or first-line therapy depending on presence or absence of other central nervous system (CNS) stimulants prescriptions 90 days prior to the first pemoline claim. Logistic regression was performed to compare second-line and first-line usage with regard to patient age, gender and prescribing physician specialty and region of practice.

Of 1,279,296 prescription claims for CNS stimulants, 17,256 (1.3%) were for pemoline. Nine hundred thirteen patients received pemoline and had 90 days or more prior enrollment. Overall, 10% of patients receiving pemoline received it as second-line therapy (95%CI: 8-12%). After adjusting for age, gender, specialty, and region, the odds of receiving pemoline as second-line therapy were significantly greater in pediatrics relative to adults (OR = 2.82, 95%CI: 1.58-5.03), and among those whose prescribers were psychiatrists versus primary care physicians (OR = 2.48, 95%CI: 1.37-4.50). Children treated by a psychiatrist had the greatest likelihood for use as second-line therapy (36%, 95%CI: 19-56%).

Among patients who received pemoline, concordance with second-line therapy recommendations was low, even among the primary target audience of children. These results in a large geographically diverse patient population are consistent with an earlier regional study.