Immunogenicity of Inactivated Varicella Zoster Vaccine in Autologous Hematopoietic Stem Cell Transplant Recipients and Patients With Solid or Hematologic Cancer.

Abstract

BackgroundIn phase 3 trials, inactivated varicella zoster virus (VZV) vaccine (ZVIN) was well tolerated and efficacious against herpes zoster (HZ) in autologous hematopoietic stem cell transplant (auto-HSCT) recipients and patients with solid tumor malignancies receiving chemotherapy (STMc) but did not reduce HZ incidence in patients with hematologic malignancies (HMs). Here, we describe ZVIN immunogenicity from these studies.MethodsPatients were randomized to ZVIN or placebo (4 doses). Immunogenicity was assessed by glycoprotein enzyme-linked immunosorbent assay (gpELISA) and VZV interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assay in patients receiving all 4 doses without developing HZ at the time of blood sampling.ResultsEstimated geometric mean fold rise ratios (ZVIN/placebo) by gpELISA and IFN-y ELISPOT ~28 days post–dose 4 were 2.02 (95% confidence interval [CI], 1.53–2.67) and 5.41 (95% CI, 3.60–8.12) in auto-HSCT recipients; 1.88 (95% CI, 1.79–1.98) and 2.10 (95% CI, 1.69–2.62) in patients with STMc; and not assessed and 2.35 (95% CI, 1.81–3.05) in patients with HM.ConclusionsZVIN immunogenicity was directionally consistent with clinical efficacy in auto-HSCT recipients and patients with STMc even though HZ protection and VZV immunity were not statistically correlated. Despite a lack of clinical efficacy in patients with HM, ZVIN immunogenicity was observed in this population. Immunological results did not predict vaccine efficacy in these 3 populations.Clinical trial registrationNCT01229267, NCT01254630.