Cost-Effectiveness of Herpes Zoster Vaccine for Persons Aged 50 Years

Abstract

Background: Each year, herpes zoster (HZ) affects 1 million U.S. adults, many of whom develop postherpetic neuralgia (PHN). Zoster vaccine is licensed for persons aged 50 years or older, but its cost-effectiveness for those aged 50 to 59 years is unknown.

Objective: To estimate the cost-effectiveness of HZ vaccine versus no vaccination.

Design: Markov model.

Data sources: Medical literature.

Target population: Adults aged 50 years.

Time horizon: Lifetime.

Perspective: Societal.

Intervention: HZ vaccine.

Outcome measures: Number of HZ and PHN cases prevented and incremental cost per quality-adjusted life-year (QALY) saved.

Results of base-case analysis: For every 1000 persons receiving the vaccine at age 50 years, 25 HZ cases and 1 PHN case could be prevented. The incremental cost-effectiveness ratio (ICER) for HZ vaccine versus no vaccine was $323 456 per QALY.

Results of sensitivity analysis: In deterministic and scenario sensitivity analyses, the only variables that produced an ICER less than $100 000 per QALY were vaccine cost (at a value of $80) and the rate at which efficacy wanes. In probabilistic sensitivity analysis, the mean ICER was $500 754 per QALY (95% CI, $93 510 to $1 691 211 per QALY). At a willingness-to-pay threshold of $100 000 per QALY, the probability that vaccination would be cost-effective was 3%.

Limitation: Long-term effectiveness data for HZ vaccine are lacking for 50-year-old adults.

Conclusion: Herpes zoster vaccine for persons aged 50 years does not seem to represent good value according to generally accepted standards. Our findings support the decision of the Advisory Committee on Immunization Practices not to recommend the vaccine for adults in this age group.

Primary funding source: None.