title: Impact of interventions designed to increase market share and prescribing of fexofenadine at HMOs.
abstract: The impact of interventions designed to shift prescribing from loratadine to fexofenadine at HMOs was studied. Pharmacy claims data for a six-month preintervention period at four HMOs were analyzed to identify all new and refill prescriptions for loratadine, fexofenadine, astemizole, and cetirizine. The interventions consisted of a mandatory lockout of loratadine in favor of fexofenadine (at HMO A), a voluntary switch to fexofenadine promoted through letters to both physicians and members (HMO B), and a voluntary switch promoted through letters to physicians only (HMO C). There was no intervention at HMO D. Pharmacy claims data for the six months after each intervention program was implemented were analyzed to determine changes in the market share and prescribing of the study drugs. After the intervention programs were implemented, the market share of fexofenadine increased from 18.9% to 65.2% at HMO A, from 14.8% to 21.0% at HMO B, and from 20.7% to 23.8% at HMO C. Loratadine's market share decreased from 62.3% to 8.7% at HMO A, from 67.5% to 58.6% at HMO B, and from 70.5% to 65.3% at HMO C. HMOs A, B, and C each had greater shifts in market share for fexofenadine and loratadine than the control HMO. Changes in prescribing followed a similar pattern for the 25 physicians at each HMO who had most frequently prescribed loratadine during the preintervention period. The average cost per antihistamine prescription decreased 22.3% at HMO A. Prescription costs continued to rise at HMOs B, C, and D. Mandating the use of fexofenadine produced a significant increase in its market share, reduced the cost of nonsedating antihistamines, and successfully influenced prescribing behavior. Voluntary programs had a more modest impact on market share and did not stop increases in prescription costs.
authors.affiliation: Advance Paradigm Clinical Services (APCS), Hunt Valley, MD 21031, USA. sbenedet@apclinical.com
authors.forename: S R
authors.initials: SR
authors.lastname: Benedetto
authors.forename: A S
authors.initials: AS
authors.lastname: Sloan
authors.forename: B S
authors.initials: BS
authors.lastname: Duncan
mesh_terms: D000704:Analysis of Variance; D016589:Astemizole / Q000191:economics / Q000627:therapeutic use; D017332:Cetirizine / Q000191:economics / Q000627:therapeutic use; D017046:Cost Savings / Q000191:economics / Q000706:statistics & numerical data; D016527:Drug Costs; D004363:Drug Utilization / Q000191:economics* / Q000706:statistics & numerical data; D006279:Health Maintenance Organizations; D006634:Histamine H1 Antagonists / Q000191:economics / Q000627:therapeutic use*; D006801:Humans; D017336:Loratadine / Q000191:economics / Q000627:therapeutic use; D008389:Marketing of Health Services; D010818:Practice Patterns, Physicians' / Q000191:economics* / Q000706:statistics & numerical data; D012189:Retrospective Studies; D016593:Terfenadine / Q000031:analogs & derivatives* / Q000191:economics / Q000627:therapeutic use; D014481:United States
chemical_list: D006634:Histamine H1 Antagonists; D017336:Loratadine; D016593:Terfenadine; D016589:Astemizole; C093230:fexofenadine; D017332:Cetirizine