Real-world evidence on adherence and completion of the two-dose recombinant zoster vaccine and associated factors in U.S. adults, 2017-2021

Public health impact of herpes zoster vaccination on older adults in Singapore: a modeling study

In Singapore, population aging and rising life expectancy are increasing herpes zoster (HZ) burden, which may be reduced by vaccination. The present study modeled the public health impact of HZ vaccination in Singapore using ZOster ecoNomic Analysis (ZONA) model adapted with Singapore-specific key model inputs, where available. Base case analysis was conducted in adults ≥ 50 years of age (YOA), exploring three vaccination strategies (no vaccination, recombinant zoster vaccine [RZV], zoster vaccine live [ZVL]) under mass vaccination setting (30% coverage). Scenario and sensitivity analyses were performed. Out of 1.51 million adults in 2021 (base case population), 406,513 (27.0%) cases of HZ, 68,264 (4.5%) cases of post-herpetic neuralgia (PHN), and 54,949 (3.6%) cases of other complications were projected without vaccination. RZV was estimated to avoid 73,129 cases of HZ, 11,094 cases of PHN, and 9,205 cases of other complications over the subjects' remaining lifetime; ZVL would avoid 17,565 cases of HZ, 2,781 cases of PHN, and 1,834 cases of other complications. The number needed to vaccinate to prevent one case of HZ/PHN was lower for RZV (7/41) than ZVL (26/163). Among all five age-stratified cohorts (50-59/60-64/65-69/70-79/≥80 YOA), RZV (versus no vaccination/ZVL) avoided the largest number of cases in the youngest cohort, 50-59 YOA. Results were robust under scenario and sensitivity analyses. Mass vaccination with RZV is expected to greatly reduce the public health burden of HZ among Singapore individuals ≥ 50 YOA. Findings support value assessment and decision-making regarding public health vaccination strategies for HZ prevention in Singapore.

Attitudes, barriers, and facilitators to adherent completion of the recombinant zoster vaccine regimen in Canada: Qualitative interviews with healthcare providers and patients

This qualitative, cross-sectional study aimed to understand the barriers and facilitators related to the adherence and completion of the recombinant zoster vaccine (RZV) two-dose series in Canada, as perceived by healthcare providers (HCPs) and patients. Data collection occurred via 60-minute concept elicitation interviews with 12 HCPs (4 physicians, 2 nurse practitioners, 6 pharmacists) who had prescribed and/or administered RZV in Canada, and 21 patients aged ≥50 years who had received ≥1 dose of RZV. Patients were categorized as adherent (received both doses within the recommended 2-to-6-month timeframe; n = 11) or non-adherent (received only one dose or second dose outside the recommended timeframe; n = 10). Interview transcripts were coded and analyzed using a two-part thematic analysis approach. HCP-identified barriers to RZV adherence included high out-of-pocket cost, inconsistent/lack of health plan coverage, inconvenient processes for accessing RZV, and patient forgetfulness. HCP-identified facilitators included desire for shingles protection, HCP encouragement, and reminders. Barriers to RZV adherence identified by patients included lack of HCP knowledge/experience with RZV, receiving unreliable/confusing information, having unpleasant/severe side effects following the first dose, high out-of-pocket cost, lack of insurance coverage, and forgetfulness. Patient-identified facilitators included self-motivation, financial support, convenient processes for obtaining RZV, and reminders. In conclusion, many factors can influence RZV series completion and adherence among adults in Canada, including cost, insurance coverage, HCP knowledge and encouragement, and reminders. Awareness of these factors may inform HCPs in helping patients overcome barriers and identify opportunities for future consideration, facilitating protection against herpes zoster.

Modelling the Public Health Burden of Herpes Zoster and the Impact of Adjuvanted Recombinant Zoster Vaccine in Five Selected Countries in Southeast Asia

INTRODUCTION

Herpes zoster (HZ) can cause substantial patient morbidity and lead to large healthcare costs. However, the disease burden of HZ in Southeast Asia may be underestimated. This study aimed to estimate the public health burden of HZ and the impact of vaccinating adults aged ≥ 50 years old in five Southeast Asian countries (Indonesia, Malaysia, Philippines, Thailand, and Vietnam), with adjuvanted recombinant zoster vaccine (RZV) compared with no vaccination.

METHODS

For each country, we adapted a static multicohort Markov model developed with a 1-year cycle length and lifetime horizon. Demographics were obtained from the World Health Organization, HZ incidence from a worldwide meta-regression reporting Asian-specific values, proportions of postherpetic neuralgia (PHN) and non-PHN complications from local/regional studies, and vaccine efficacy from a long-term follow-up trial. First-dose coverage and second-dose compliance were assumed to be 30% and 70%, respectively. A one-way deterministic sensitivity analysis (OWSA) and probabilistic sensitivity analysis (PSA) were performed to assess the robustness and uncertainty of inputs for each country.

RESULTS

Without RZV, it was estimated that there would be a total of approximately 10 million HZ cases, 2.1 million PHN cases, and 1.4 million non-PHN complications in individuals aged ≥ 50 years included in the model. Introducing RZV under 30% coverage could avoid approximately 2.2 million (22%) HZ cases, almost 500,000 (21%) PHN cases, and around 300,000 (22%) non-PHN complications. OWSA showed that first-dose coverage and initial HZ incidence had the largest impact on the estimated number of HZ cases avoided. The number needed to vaccinate ranged from 15 to 21 to prevent one case of HZ and from 68 to 104 to prevent one case of PHN across each country.

CONCLUSIONS

This study demonstrated that there is substantial HZ disease burden in older adults for the five selected countries in Southeast Asia, negatively impacting national healthcare systems. Introducing RZV could potentially reduce this burden. A graphical abstract is available with this article.

2022 national survey of immunizing community chain pharmacists: The case for codifying the PREP Act emergency authorities into practice

BACKGROUND

Pharmacy-based immunization services have expanded since the mid-1990s but still face multiple challenges. Amendments to the Public Readiness and Emergency Preparedness (PREP) Act broadened patient-care scope and the pool of eligible pharmacy personnel who could administer vaccinations. The expiration of these amendments in 2024 may threaten recent gains in vaccine and other health care access newly available through pharmacies.

OBJECTIVES

This study aimed to elicit community chain pharmacists' perspectives on immunization time demands, corporate guidance, data flow and information technology, workflow and workforce issues, and other newly provided services.

METHODS

A survey questionnaire was developed, pretested, and electronically administered in mid-2022 to a randomly sampled national database of pharmacists maintained by the American Pharmacists Association. Descriptive analyses of survey responses were performed and findings used to identify salient themes.

RESULTS

The survey collected 742 responses from a sample of 7845 community chain pharmacists (9.5% response rate). During the 2021-2022 influenza season, pharmacies administered on average 114 vaccinations daily (range 3-1000), mostly by appointment (51%). Pharmacists expressed somewhat greater preference for administering vaccinations (39%) than dispensing prescriptions (36%), and most (92%) considered it at least as important as other practice responsibilities. However, only 27% of pharmacists had adequate staff support and 67% spent more time addressing patients' vaccination confidence issues than before the pandemic. Most respondents (67%) had access to their patient's vaccination status, but only 51% said their company's computer system gave easy access. Only 49% considered corporate immunization feedback effective at enhancing their practice. Provision of nonvaccine services has expanded.

CONCLUSIONS

Frontline community chain pharmacists reportedly preferred administering vaccinations over dispensing prescriptions. The pandemic resulted in an increased responsibility among pharmacists as immunizers. Notwithstanding recent progress, pharmacists continue to face staffing, corporate guidance and feedback, information management, and other structural and process barriers to optimally provide comprehensive immunization services. Survey findings support making permanent and expanding the emergency authorities that pharmacists gained under the PREP Act.

Effectiveness and safety of recombinant zoster vaccine: A review of real-world evidence

The recombinant zoster vaccine (RZV) was licensed in the US for prevention of herpes zoster (HZ) in 2017. We conducted a literature search (January 1, 2017-August 1, 2023) using PubMed, Embase, and Scopus to consolidate the real-world evidence related to RZV. Overall, RZV effectiveness against HZ was high across the studied populations in real-world settings, including adults aged ≥ 50 years and patients aged ≥ 18 years with immunodeficiency or immunosuppression. Effectiveness was higher with two doses versus one dose, especially in elderly people and immunocompromised individuals. The safety profile of RZV was broadly consistent with that established in clinical trials. RZV does not appear to increase the risk of disease flares in patients with immune-mediated diseases. Approximately two-thirds of individuals received a second RZV dose within 2-6 months after the first dose. Collectively, RZV effectiveness against HZ was high, and these real-world studies reaffirm its favorable benefit-risk profile.

The potential impact of increased recombinant zoster vaccine coverage on the burden of herpes zoster among adults aged 50-59 years

INTRODUCTION

Recombinant zoster vaccine (RZV) is recommended in the US for prevention of herpes zoster (HZ) in adults aged ≥50 years. Vaccination rates remain suboptimal for adults 50-59 years compared with adults ≥50 years overall. The objective of this study was to model changes in outcomes associated with improved RZV vaccination coverage in US adults 50-59 years.

METHODS

A multicohort Markov model compared a scenario using real-world vaccination coverage for US adults 50-59 years in 2020 versus scenarios assuming higher coverage. Outcomes, based on a lifetime horizon, included HZ cases and complications avoided, quality-adjusted life-years (QALY), and costs. Model inputs included HZ epidemiology, RZV vaccine efficacy, coverage, adverse events, and costs, based on published literature and US sources. Some inputs were updated from previous models, including real-world estimates of RZV coverage, series completion, and reflecting longer-term data on waning of vaccine efficacy. The model utilized a cohort size of 42,756,488 individuals based on the 2020 US population census.

RESULTS

The model projected that increasing RZV coverage in adults 50-59 years from 7.3 % to 14.6 % (to coverage for adults 60-64 years in 2020) would avoid an additional 504,468 HZ cases, 42,077 postherpetic neuralgia cases, and 56,247 cases of other HZ-associated complications. The increase in vaccine coverage would result in higher vaccination-related costs of $1,172,411,566, but the avoided HZ cases and complications would be expected to result in direct cost savings of $721,973,386 and indirect cost savings of $593,497,480 from avoided productivity loss. Overall, a gain of 5,230 discounted QALYs and cost savings of $143,059,299 from a societal perspective would be realized.

CONCLUSION

Modestly higher RZV coverage in US adults 50-59 years could reduce the clinical burden associated with HZ and may result in societal cost savings. These findings demonstrate the potential value of increasing RZV vaccination in this population.