P C Langley1, S K Tyring, M H Smith. 1. University of Colorado Health Sciences Center, Denver, USA. paul.langley@UCHSC.edu
Abstract
OBJECTIVE: External genital warts are one of the fastest growing sexually transmitted diseases in the United States today. Two forms of therapy are available: provider-administered and patient-applied. In the most widely used provider-administered ablative therapies, sustained clearance rates range from 18.5% to 40.1%. With nonablative, patient-applied therapies, which are typically more acceptable to patients, sustained clearance rates range from 19.6% with podofilox gel to 44.0% with imiquimod cream. The purpose of this study, given the range of therapies available, their cost differences, and clinical trial-reported differences in rates of sustained clearance, is to determine which therapy modalities, from the providers' perspective, are the most cost effective and which are likely to be the most acceptable to the patient population. STUDY DESIGN: We consider the cost effectiveness of the two patient-applied therapies as first-line therapy followed by provider-administered ablative treatment as second-line therapy. A decision-analytic model framework is developed, with data drawn both from clinical trials and from previously published studies. RESULTS: When considering a two-stage therapy model, with an average sustained clearance rate of 30% assumed for provider-administered ablative therapies, estimated costs per sustained cleared patient are $1265 for patients initially treated with imiquimod and $1304 for patients initially treated with podofilox gel. CONCLUSIONS: Initial treatment with imiquimod is the preferred intervention option as it yields a 39% greater sustained clearance rate than podofilox gel while being 3% less costly per successful outcome.
OBJECTIVE: External genital warts are one of the fastest growing sexually transmitted diseases in the United States today. Two forms of therapy are available: provider-administered and patient-applied. In the most widely used provider-administered ablative therapies, sustained clearance rates range from 18.5% to 40.1%. With nonablative, patient-applied therapies, which are typically more acceptable to patients, sustained clearance rates range from 19.6% with podofilox gel to 44.0% with imiquimod cream. The purpose of this study, given the range of therapies available, their cost differences, and clinical trial-reported differences in rates of sustained clearance, is to determine which therapy modalities, from the providers' perspective, are the most cost effective and which are likely to be the most acceptable to the patient population. STUDY DESIGN: We consider the cost effectiveness of the two patient-applied therapies as first-line therapy followed by provider-administered ablative treatment as second-line therapy. A decision-analytic model framework is developed, with data drawn both from clinical trials and from previously published studies. RESULTS: When considering a two-stage therapy model, with an average sustained clearance rate of 30% assumed for provider-administered ablative therapies, estimated costs per sustained cleared patient are $1265 for patients initially treated with imiquimod and $1304 for patients initially treated with podofilox gel. CONCLUSIONS: Initial treatment with imiquimod is the preferred intervention option as it yields a 39% greater sustained clearance rate than podofilox gel while being 3% less costly per successful outcome.