An early look at the second dose completion of the recombinant zoster vaccine in Canadian adults: A retrospective database study

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.

Updated Public Health Impact and Cost Effectiveness of Recombinant Zoster Vaccine in Canadian Adults Aged 50 Years and Older

OBJECTIVES

The aim of this study was to update previously estimated public health impact and cost effectiveness of recombinant zoster vaccine (RZV) for the prevention of herpes zoster (HZ) in Canadians aged ≥50 years using longer-term RZV efficacy and waning data and real-world coverage and completion.

METHODS

A multicohort Markov model was used to conduct a cost-utility analysis comparing RZV with no HZ vaccination among Canadians aged ≥50 years. Real-world data were used for first-dose coverage (17.5%) and second-dose completion (65%). Vaccine efficacy and waning data were applied from up to 8-year follow-up from the ZOE-50 and ZOE-70 clinical trials. Incremental costs and benefits were calculated using a lifetime horizon from the healthcare payer (base case) and societal perspectives. A discount rate of 1.5% was applied to costs and quality-adjusted life-years (QALYs).

RESULTS

The model estimated that RZV would prevent 303,835 HZ cases, 83,256 post-herpetic neuralgia (PHN) cases, 39,653 other complications, and 99 HZ-related deaths compared with no HZ vaccination. Incremental cost-effectiveness ratios (ICERs) were estimated to be $27,486 and $22,097 per QALY (2022 Canadian dollars [CAN$]) from the healthcare payer and societal perspectives, respectively. The base-case ICER was most sensitive to a lower percentage of initial HZ cases with PHN. Almost all probabilistic sensitivity analysis simulations (98.1%) resulted in ICERs

CONCLUSIONS

RZV is expected to remain a cost-effective option for Canadian adults aged ≥50 years when using longer-term RZV efficacy and waning estimates, although the estimated public health impact was smaller than in the previous analysis (due to lower coverage/completion estimates).

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Grants

• GlaxoSmithKline Biologicals

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Affiliation(s)

Sydney George GSK, Mississauga, ON, Canada.
Justin Carrico RTI Health Solutions, Research Triangle Park, NC, USA
Katherine A Hicks RTI Health Solutions, Research Triangle Park, NC, USA
Dessi Loukov GSK, Mississauga, ON, Canada
Cheryl Ng GSK, Singapore, Singapore
Jessica Regan GSK, Mississauga, ON, Canada
Nikolaos Giannelos GSK, Wavre, Belgium

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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.

Patterns of use of recombinant zoster vaccine among commercially-insured immunocompetent and immunocompromised adults 50-64 years old in the United States

PURPOSE

The Centers for Disease Control and Prevention (CDC) recommends recombinant zoster vaccination (RZV) for adults ≥ 50 years to prevent herpes zoster (HZ) and its sequelae. Initially, no distinct recommendation was made for immunocompromised adults, who experience higher HZ rates and more severe outcomes. We characterized receipt of first RZV dose (initiation) and both doses (completion) over time, and the impact of immune function on RZV uptake among adults aged 50-64 years in the United States.

METHODS

We identified RZV claims from the IBM MarketScan database between 1/1/2018 and 12/31/2019. We characterized immunocompromised enrollees as having malignancy, HIV, solid organ transplant, primary immunosuppression, or medication-induced immunosuppression using inpatient, outpatient, and prescription claims in the 6 months prior to study start. We evaluated patterns of vaccine uptake by demographic and healthcare access characteristics and immune status.

RESULTS

The cumulative incidence of RZV initiation during the study period was 10.0%. Incidence increased with age and number of medical office visits, and was higher among women, urban residents, high-deductible insurance beneficiaries, and those who were immunocompromised compared to immunocompetent. Among immunocompromised adults, RZV initiation was highest among those with HIV and primary immunodeficiencies. Of those who initiated RZV, 89.5% received both doses. RZV completion was highest among those who received the first dose at a pharmacy. Most enrollees (88.6%) who completed RZV vaccination did so within the recommended dosing schedule.

CONCLUSIONS

RZV uptake was low in the two years since the CDC recommendation, and differed by demographic, healthcare access, and clinical characteristics. Initiation rates were higher among immunocompromised adults compared to immunocompetent adults, despite no CDC recommendation for vaccination in these groups during the study period. The CDC has since recommended RZV for immunocompromised individuals, and our findings may inform efforts to increase RZV uptake in individuals at higher risk of severe disease.

Recombinant zoster vaccine (RZV) second-dose series completion in adults aged 50-64 years in the United States

In 2018, CDC recommended a highly efficacious adjuvanted recombinant zoster vaccine (RZV) as a 2-dose series for prevention of herpes zoster (HZ) for immunocompetent persons age ≥ 50 years, with the 2nd dose recommended 2-6 months after the 1st dose. We estimated second-dose RZV series completion in the U.S. among 50-64-year-olds using two administrative databases. Second-dose RZV series completion was ∼70% within 6-months and 80% within 12-months of first dose. Among those who received only 1 RZV dose with at least 12 months of follow-up time, 96% had a missed opportunity for a second-dose vaccination, defined as a provider or pharmacy visit, among whom 36% had a visit for influenza or pneumococcal vaccination within 2-12 months of their first-dose of RZV. We found that RZV series completion rates in 50-64-year-olds was high. Availability of RZV at pharmacies has potentially helped increase series completion, but missed opportunities remain.

Recombinant Zoster Vaccine Uptake and Risk of Flares Among Older Adults with Immune-Mediated Inflammatory Diseases in the United States

OBJECTIVE

Persons with immune-mediated inflammatory diseases (IMIDs) are at increased risk of herpes zoster (HZ). In 2018, CDC recommended a highly efficacious vaccine, recombinant zoster vaccine (RZV), for prevention of HZ in immunocompetent ≥50 years-olds. We estimated RZV vaccination among adults age ≥50 years with IMIDs during 2018-2019 and examined possible vaccine-related flares following RZV.

METHODS

We identified a cohort of IMID patients using medical claims data from IBM® MarketScan® (age 50-64 years) and Centers for Medicare and Medicaid Services Medicare (age ≥65 years). Presumed flares were defined as hospitalization/emergency department visit for their respective IMIDs, or steroid treatment with a short-acting oral glucocorticoid or parenteral glucocorticoid injection. We conducted a self-controlled case series (SCCS) analysis to examine a temporal association between RZV and flares.

RESULTS

Among enrollees with IMIDs, 14.8% of 55,654 MarketScan and 43.2% of 160,545 Medicare enrollees received ≥1-dose of RZV during 2018-2019. Two-dose series completion was 76.6% in MarketScan and 85.4% in Medicare enrollees. In the SCCS analysis, 10% and 13% developed flares in the control as compared to 9% and 11-12% in the risk window following 1- or 2-doses of RZV among MarketScan and Medicare enrollees, respectively. We found no statistically significant increase in flares following RZV administration for any IMID in either age group following RZV dose-1 or dose-2.

CONCLUSIONS

We did not find an increase in presumed flares following RZV vaccination. Among adults aged ≥50 years with IMIDs, a substantial proportion received RZV compared to general zoster coverage estimates and series-completion was high. This article is protected by copyright. All rights reserved.