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


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)
Figure 2. Cell-mediated immune responses to RZV in immunocompromised populations (adapted ATP cohort for cell-mediated immunogenicity)


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