Safety and immunogenicity of an ASO1 -adjuvanted varicella-zoster virus subunit candidate vaccine against herpes zoster in adults ≥50 years of age

Abstract

Methods. This was a phase II, observer-blind, randomized, multinational study. Adults ≥50 years old were randomized 4:4:2:1 to be vaccinated at months 0 and 2 with gE combined with a higher (AS01B) or lower (AS01E) dose adjuvant, unadjuvanted gE, or saline. Following each dose, solicited events were recorded for 7 days and unsolicited adverse events for 30 days. Serious adverse events were collected for 1 year. Cell-mediated and humoral immune responses were assessed at baseline and following each dose. Results. No vaccine-related severe adverse events were reported. Solicited adverse events were generally mild to moderate and transient. For all gE-based vaccines, pain was the most common local symptom and fatigue the most common general symptom. Immune responses were significantly enhanced by AS0IB and AS01E compared to unadjuvanted gE and were significantly stronger for gE/AS01 B than for gE/AS01E. Conclusions. AS01 improved the immunogenicity of gE while retaining acceptable safety and reactogenicity profiles. The enhancement of gE-specific cellular and humoral responses was adjuvant dose dependent. © The Author 2013.