Prospective, Longitudinal Study on Specific Cellular Immune Responses after Vaccination with an Adjuvanted, Recombinant Zoster Vaccine in Kidney Transplant Recipients

Recombinant zoster vaccine in immunocompetent and immunocompromised adults: A review of clinical studies

Herpes zoster (HZ) is a debilitating vaccine-preventable disease. Impairment of cell-mediated immunity, as observed with aging and immunosuppressive disorders and therapies, increases risk. Recombinant zoster vaccine (RZV) is efficacious against HZ in adults aged ≥50 years in different settings, and in immunocompromised adults aged ≥18 years who are at increased risk of developing HZ. RZV is the first and only HZ vaccine approved for use in immunocompromised adults globally, including in Europe and the US. RZV has a clinically acceptable safety profile and elicits robust immune responses in adults aged ≥50 years, and in immunocompromised adults aged ≥18 years who are at increased risk of HZ. Additionally, RZV is efficacious against HZ complications such as post-herpetic neuralgia and HZ-related pain. This review updates knowledge from a randomized controlled trial setting on the efficacy, safety, immunogenicity, and impact on quality of life of RZV.

Tiza-Titre increase and enhanced immunity through an adjuvanted, recombinant herpes zoster subunit vaccine in patients with liver cirrhosis and post-liver transplantation: a study protocol for a prospective cohort study

INTRODUCTION

Shingrix, an effective adjuvanted, recombinant herpes zoster vaccine (RZV), has been available since 2018. Immunocompromised patients are known to be predisposed to vaccine failure. In-vitro testing of immunological surrogates of vaccine protection could be instrumental for monitoring vaccination success. So far, no test procedure is available for vaccine responses to RZV that could be used on a routine basis.

METHODS AND ANALYSIS

This is a single-centre, three-arm, parallel, longitudinal cohort study aspiring to recruit a total of 308 patients (103 with a liver cirrhosis Child A/B, 103 after liver transplantation (both ≥50 years), 102 immunocompetent patients (60-70 years)). Blood samples will be taken at seven data collection points to determine varicella zoster virus (VZV) and glycoprotein E (gE)-specific IgG and T cell responses. The primary study outcome is to measure and compare responses after vaccination with RZV depending on the type and degree of immunosuppression using gE-specific antibody detection assays. As a secondary outcome, first, the gE-specific CD4+ T cell response of the three cohorts will be compared and, second, the gE-VZV antibody levels will be compared with the severity of possible vaccination reactions. The tertiary outcome is a potential association between VZV immune responses and clinical protection against shingles.

ETHICS AND DISSEMINATION

Ethical approval was issued on 07/11/2022 by the Ethics Committee Essen, Germany (number 22-10805-BO). Findings will be published in peer-reviewed open-access journals and presented at local, national and international conferences.

TRIAL REGISTRATION NUMBER

German Clinical Trials Registry (number DRKS00030683).

Herpes Virus Infections in Kidney Transplant Patients (HINT) - a prospective observational cohort study

BACKGROUND

Kidney transplant recipients receive maintenance immunosuppressive therapy to avoid allograft rejection resulting in increased risk of infections and infection-related morbidity and mortality. Approximately 98% of adults are infected with varicella zoster virus, which upon reactivation causes herpes zoster. The incidence of herpes zoster is higher in kidney transplant recipients than in immunocompetent individuals, and kidney transplant recipients are at increased risk of severe herpes zoster-associated disease. Vaccination with adjuvanted recombinant glycoprotein E subunit herpes zoster vaccine (RZV) prevents herpes zoster in older adults with excellent efficacy (90%), and vaccination of kidney transplant candidates is recommended in Danish and international guidelines. However, the robustness and duration of immune responses after RZV vaccination, as well as the optimal timing of vaccination in relation to transplantation remain unanswered questions. Thus, the aim of this study is to characterize the immune response to RZV vaccination in kidney transplant candidates and recipients at different timepoints before and after transplantation.

METHODS

The Herpes Virus Infections in Kidney Transplant Patients (HINT) study is a prospective observational cohort study. The study will include kidney transplant candidates on the waiting list for transplantation (n = 375) and kidney transplant recipients transplanted since January 1, 2019 (n = 500) from all Danish kidney transplant centers who are offered a RZV vaccine as routine care. Participants are followed with repeated blood sampling until 12 months after inclusion. In the case of transplantation or herpes zoster disease, additional blood samples will be collected until 12 months after transplantation. The immune response will be characterized by immunophenotyping and functional characterization of varicella zoster virus-specific T cells, by detection of anti-glycoprotein E antibodies, and by measuring cytokine profiles.

DISCUSSION

The study will provide new knowledge on the immune response to RZV vaccination in kidney transplant candidates and recipients and the robustness and duration of the response, potentially enhancing preventive strategies against herpes zoster in a population at increased risk.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT05604911).

Current Perspectives on the Management of Herpesvirus Infections in Solid Organ Transplant Recipients

Solid organ transplant recipients (SOTRs) are at high risk of human herpesvirus (HHV)-related morbidity and mortality due to the use of immunosuppressive therapy. We aim to increase awareness and understanding of HHV disease burden in SOTRs by providing an overview of current prevention and management strategies as described in the literature and guidelines. We discuss challenges in both prevention and treatment as well as future perspectives.

Immunization of Solid Organ Transplant Candidates and Recipients: A 2022 Update

Immunizations are a relatively safe and cost-effective intervention to prevent morbidity and mortality associated with vaccine preventable infection (VPIs). As such, immunizations are a critical part of the care of pre and posttransplant patients and should be prioritized. New tools are needed to continue to disseminate and implement the most up-to-date vaccine recommendations for the SOT population. These tools will help both primary care providers and multi-disciplinary transplant team members taking care of transplant patients to stay abreast of evidence-based best practices regarding the immunization of the SOT patient.

Long-Term Follow-Up after Adoptive Transfer of BK-Virus-Specific T Cells in Hematopoietic Stem Cell Transplant Recipients

The BK virus (BKV) causes severe hemorrhagic cystitis in hematopoietic stem cell transplant (HSCT) recipients. To eliminate reactivated BKV, symptomatic patients can be treated with a reduction of the immunosuppressive therapy, with the antiviral drug cidofovir, or with virus-specific T cells (VSTs). In the current study, we compared the effect of VSTs to other treatment options, following up specific T cells using interferon-gamma ELISpot assay. We observed BKV large T-specific cellular responses in 12 out of 17 HSCT recipients with BKV-related cystitis (71%). In recipients treated with VSTs, 6 out of 7 showed specific T-cell responses, and that number in those without VSTs was 6 out of 10. In comparison, 27 out of 50 healthy controls (54%) responded. In HSCT recipients treated for BKV-related cystitis, absolute CD4+ T-cell numbers and renal function correlated with BKV-specific cellular responses (p = 0.03 and 0.01, respectively). In one patient, BKV-specific cellular immunity could already be detected at baseline, on day 35 after HSCT and prior to VSTs, and remained increased until day 226 after VSTs (78 vs. 7 spots increment). In conclusion, the ELISpot appears to be suitable to sensitively monitor BKV-specific cellular immunity in HSCT recipients, even early after transplantation or in the long term after VSTs.