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

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.