Individuals who are immunocompromised (IC) due to disease or therapy are at increased risk of herpes zoster (HZ), with HZ cases in IC populations also resulting in increased health care resource use and costs as compared with the immunocompetent population. This study assesses the cost-effectiveness of recombinant zoster vaccine (RZV) versus no vaccine for the prevention of HZ in IC adults aged ≥18 years in the United States (US).
METHODS: A Markov model with a one-year cycle length was developed to follow a hypothetical cohort of 1 million IC individuals for a 30-year time horizon. The model estimates health and cost outcomes associated with RZV versus no vaccine. The base-case analysis considered hematopoietic stem cell transplant (HSCT) recipients who were assumed to remain IC for five years post-transplant. Two-dose compliance was assumed to be 100%, with efficacy and waning inputs based on clinical trial data. Epidemiological, cost, and utility inputs were obtained from standard US sources and published literature. Costs and quality-adjusted life-years (QALYs) were discounted at 3% per year. Sensitivity, threshold, and scenario analyses were conducted, including scenarios of four other IC conditions.
RESULTS: Based on the modeled hypothetical cohort of 1 million HSCT recipients, RZV was associated with 116,790 fewer HZ cases and 21,446 fewer postherpetic neuralgia cases versus no vaccine, resulting in 5,545 fewer QALYs lost and a societal cost-savings of $5.4 million. The number needed to vaccinate to prevent one HZ case was estimated to be 8.6. HSCT population results were robust across a range of sensitivity and threshold analyses. In scenario analyses, RZV was also cost saving for renal transplant recipients. Incremental cost-effectiveness ratios for other IC populations were $33,268 per QALY gained for human immunodeficiency virus, $67,682 for breast cancer, and $95,972 for Hodgkin lymphoma.
CONCLUSION: Results suggest that RZV is a cost-effective option for vaccinating US IC adults for the prevention of HZ and associated complications.
