Impact of formulary management and step therapy for non-sedating antihistamines on prescription drug utilisation and costs

Abstract

SummaryNon-sedating antihistamines (NSAs) make up a high-volume, high-cost drug category in most health plans. A pre-post retrospective cohort study design was used to assess the effects of different pharmacy benefit strategies on utilisation and costs of NSAs. The cohort with formulary change plus step therapy programme experienced close to a 35% decrease in NSA utilisation and per member per month (PMPM) total costs (p<0.0001). The cohorts with either a NSA step therapy programme or a formulary change experienced 26.56% (p<0.0001) and 9.85% (p=0.1955) reduction in NSA utilisation and a 24.59% (p<0.0001) and 7.69% (p=0.3042) decrease in PMPM total costs, respectively. The control cohort that maintained the preferred status of prescription NSAs with no step therapy programme had an increase both in NSA utilisation (1.25%; p=0.8285) and PMPM total costs (3.26%; p=0.4245). In comparison with the control cohort, the NSA formulary plus step therapy programme was estimated to have resulted in PMPM total cost savings of $0.56 (p<0.0001). The NSA formulary plus step therapy programme led to cost savings by controlling the utilisation of and expenditures for prescription NSAs.