2779. Efficacy of the Adjuvanted Recombinant Zoster Vaccine According to Sex, Geographic Region, and Geographic Ancestry/Ethnicity: A Post-hoc Analysis

BACKGROUND: The risk of herpes zoster (HZ) has been reported to vary by sex and ethnicity. In 2 large-scale clinical trials, ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229), the adjuvanted recombinant zoster vaccine (RZV) demonstrated high vaccine efficacy (VE) against HZ and post-herpetic neuralgia (PHN). We present a post-hoc analysis of RZV efficacy against HZ and PHN in the ZOE-50/70 population stratified by sex, geographic region and geographic ancestry/ethnicity. METHODS: The ZOE-50 and ZOE-70 studies were phase III, observer-blind, placebo-controlled trials conducted across 5 geographic regions. Adults ≥ 50 years of age (YOA; ZOE-50) and ≥ 70 YOA (ZOE-70), randomized 1:1, received 2 doses of RZV or placebo 2 months apart. Here, VE against HZ by sub-population was estimated from the ZOE-50 population (≥ 50 YOA) and the pooled ZOE-50/70 population (pooled ≥ 70 YOA), and VE against PHN by sub-population was evaluated in the pooled ≥ 70 YOA. RESULTS: VE was evaluated in 7,340 RZV and 7,413 placebo recipients ≥ 50 YOA (mean age: 62.3 [RZV], 62.2 [placebo] YOA) and 8,250 RZV and 8,346 placebo recipients in pooled ≥ 70 YOA (mean age: 75.5 [RZV, placebo] YOA). VE against HZ and PHN was similar for women and men in the ≥ 50 YOA and pooled ≥ 70 YOA (Tables 1 and 2). Point estimates for VE against HZ by geographic region ranged from 95.7% to 97.2% in ≥ 50 YOA and from 87.3% to 95.1% in pooled ≥ 70 YOA (Table 1). Point estimates for VE against PHN by geographic region ranged from 86.8% to 100% in pooled ≥ 70 YOA. VE was similar across geographic ancestry groups in pooled ≥ 70 YOA: VE point estimates against HZ ranged from 89.6% to 100% and VE against PHN ranged from 87.5% to 100% (Tables 1 and 2). VE against HZ was 88.1% and against PHN was 65.9% in Hispanic participants in pooled ≥ 70 YOA (Tables 1 and 2). CONCLUSION: Acknowledging the limitations including the post-hoc character of these analyses and the small number of participants and cases available, our data suggest that RZV is efficacious against HZ and PHN irrespective of sex, geographic region, geographic ancestry, and ethnicity. Funding: GlaxoSmithKline Biologicals SA. [Image: see text] [Image: see text] DISCLOSURES: All authors: No reported disclosures.