OBJECTIVES: Immunocompromised (IC) individuals are at increased risk of herpes zoster (HZ). We assessed the public health impact and cost-effectiveness of recombinant zoster vaccine (RZV) versus no vaccination against HZ for IC adults aged ≥18 years in the United States (US).

METHODS: A Markov model simulated a hypothetical cohort of the estimated 19,671 US haematopoietic stem cell transplant (HSCT) recipients in 2017 (starting age=35 years, IC duration=5 years, HZ incidence=60/1,000 patient-years, starting RZV efficacy=72.5%, RZV efficacy annual waning=9.1%). RZV was compared to no vaccination with annual cycles over 30 years for avoided HZ and postherpetic neuralgia (PHN) cases, number needed to vaccinate (NNV) to avoid 1 HZ or PHN case, quality-adjusted life years (QALYs) gained, and incremental cost-effectiveness ratios (ICERs). For RZV impact in other IC populations, Scenarios A–D assessed renal transplant recipients and patients with breast cancer, Hodgkin’s lymphoma, and HIV. Scenario E varied IC duration (1–30 years), HZ incidence (10–80/1,000 patient-years), and starting age (35, 45) simultaneously.

RESULTS: For HSCT recipients, RZV (2 doses) resulted in 38% and 63% fewer HZ and PHN cases, respectively, and 109 QALYs gained, versus no vaccination. RZV was cost-saving (dominant strategy) versus no vaccination. The NNV to avoid one HZ and PHN case was 9 and 47. For scenarios A–D, the NNV to avoid one case ranged from 5–10 for HZ and 37–91 for PHN; ICERs ranged from cost-saving to $95,972 (renal transplant recipients and patients with Hodgkin’s lymphoma, respectively). Of 60 input combinations in Scenario E, most were cost-saving; 8 resulted in ICERs >$100,000.

CONCLUSIONS: Vaccinating US IC adults with RZV would reduce HZ cases and is expected to be cost-saving for HSCT recipients and cost-effective for most other modeled IC populations, versus no vaccination. Consistent with recent Advisory Committee for Immunization Practices recommendations, these results support HZ vaccination with RZV in US IC adults.