4. Immunogenicity of the Adjuvanted Recombinant Zoster Vaccine in Immunocompromised Adults

BACKGROUND: Immunocompromised (IC) populations are at increased risk of developing herpes zoster (HZ) due to disease- and/or therapy-induced immunosuppression. The adjuvanted recombinant zoster vaccine (RZV) has demonstrated 68.2% efficacy in preventing HZ in autologous hematopoietic stem cell transplant (HSCT) recipients and 87.2% efficacy in a post-hoc analysis in hematologic malignancy (HM) patients ≥ 18 years of age (YOA). Here we present the immunogenicity of RZV in representative IC populations. METHODS: Our analysis includes five phase I/II/III clinical trials conducted worldwide between 2010–2017 (Table 1) in IC populations (autologous HSCT, human immunodeficiency virus [HIV]-infected, HM, solid tumor [ST] on chemotherapy and renal transplant [RT] patients) ≥ 18 YOA. Anti-glycoprotein E (gE) antibody geometric mean concentrations (GMCs) and gE-specific CD4 T cell frequencies were descriptively evaluated by age group (18–49 YOA and ≥ 50 YOA) and overall at 1 month (M) and 12M post-last RZV dose. Table 1. Clinical studies with immunocompromised populations included in our analysis [Image: see text] RESULTS: The according-to-protocol cohorts for immunogenicity from the included trials are presented in Table 1. At 1M post-last RZV dose, anti-gE GMCs and median CD4 T-cell frequencies increased in all IC populations compared to pre-vaccination and persisted above baseline up to 12M post-last RZV dose (Figures 1 and 2). No meaningful differences were seen between age groups in terms of humoral (except a slight trend for stronger responses in the 18–49 YOA RT and HM patients compared to their corresponding ≥ 50 YOA group) and gE-specific CD4 T-cell responses in any of the IC populations. Figure 1. Humoral immune responses to RZV in immunocompromised populations (adapted ATP cohort for humoral immunogenicity) [Image: see text] Figure 2. Cell-mediated immune responses to RZV in immunocompromised populations (adapted ATP cohort for cell-mediated immunogenicity) [Image: see text] CONCLUSION: RZV induced robust and persistent humoral and cell-mediated immune (CMI) responses that lasted up to at least 12M post-last vaccination in all evaluated IC populations. Humoral responses in the IC populations were robust although not as strong as in the non-IC adults ≥ 50 YOA. CMI responses were mostly similar across IC populations and adults ≥ 50 YOA, with a potent response occurring even in ST patients undergoing chemotherapy. This data shows that RZV is immunogenic even in severely IC adults. Funding: GlaxoSmithKline Biologicals SA Acknowledgment: M Maior/S Hulsmans (Modis c/o GSK) provided writing/editorial support DISCLOSURES: Alemnew F. Dagnew, MD, MSc, GSK group of companies (Employee, Shareholder) Peter Vink, MD, GSK group of companies (Employee, Shareholder) Mamadou Drame, MSc, GSK group of companies (Employee) David Willer, PhD, GSK group of companies (Employee, Shareholder) Bruno Salaun, PhD, GSK group of companies (Employee) Anne Schuind, MD, GSK (Employee, Other Financial or Material Support, own GSK stock options or restricted shares as part of renumeration)