Prevention of herpes simplex virus eye disease - A cost-effectiveness analysis

Objectives: To estimate the cost of treating herpes simplex virus (HSV) eye disease, and to evaluate the incremental cost-effectiveness of chronic suppressive antiviral prophylaxis for reducing ocular HSV recurrences. Methods: An economic decision-tree model was used on follow-up data from 703 patients with prior ocular HSV disease who were enrolled in a Herpetic Eye Disease Study multicenter clinical trial that evaluated the prolonged use of oral acyclovir. Costs were based on wholesale drug prices, Medicare fees, and national health surveys. Incremental cost-effectiveness ratios for all patients and for patients with prior stromal keratitis were calculated as the additional net cost of acyclovir prophylaxis compared with the number of cases of ocular herpes prevented during 12 months. One- and 2-way sensitivity analyses evaluated the effect of different treatment costs and recurrence risks. Results: Approximately $17.7 million is expended annually to treat the estimated 59000 new and recurrent episodes of HSV eye disease occurring among 29000 individuals each year in the United States. Chronic suppressive oral acyclovir costs $8532 per ocular HSV episode averted. The incremental cost per infection averted would decline by up to 51% if antiviral prophylaxis were more effective and by up to 87% if patients had a higher recurrence risk. Targeting prophylaxis to patients with a history of stromal keratitis is not more cost-effective than providing oral acyclovir for patients with any prior HSV eye disease. Conclusions: Herpetic eye disease is costly to treat and prevent. Because prophylactic oral acyclovir is not a cost-effective option for all patients with previous HSV eye disease, therapeutic decisions must be made on a case-by-case basis.