Efficacy of the adjuvanted recombinant zoster vaccine (RZV) by sex, geographic region, and geographic ancestry/ethnicity: A post-hoc analysis of the ZOE-50 and ZOE-70 randomized trials.

BACKGROUND: Herpes zoster (HZ) risk appears to vary by sex and geographic ancestry/ethnicity. METHODS: In 2 randomized clinical trials, participants received 2 doses of adjuvanted recombinant zoster vaccine (RZV) or placebo intramuscularly, 2 months apart. In this post-hoc analysis, we investigate efficacy of RZV against HZ and postherpetic neuralgia (PHN) by sex, geographic region, and geographic ancestry/ethnicity in ≥50-year-olds (ZOE-50: NCT01165177) and ≥70-year-olds (pooled data from ZOE-50 and ZOE-70: NCT01165229). RESULTS: Vaccine efficacy against HZ or PHN was similar in women and men. Across geographic regions, efficacy against HZ ranged between 95.7 and 97.2% in ≥50-year-olds, and between 87.3% and 95.1% in ≥70-year-olds; efficacy against PHN ranged between 86.8 and 100% in ≥70-year-olds. Across ancestral/ethnic groups, efficacy ranged between 88.1 and 100% against HZ and between 65.9 and 100% against PHN in ≥70-year-olds. CONCLUSIONS: While the ZOE-50/70 studies were not powered or pre-designed for these post-hoc analyses, RZV appears efficacious against HZ and PHN irrespective of sex, region, or geographic ancestry/ethnicity.

Safety profile of the adjuvanted recombinant zoster vaccine: Pooled analysis of two large randomised phase 3 trials.

BACKGROUND: The ZOE-50 (NCT01165177) and ZOE-70 (NCT01165229) phase 3 clinical trials showed that the adjuvanted recombinant zoster vaccine (RZV) was ≥90% efficacious in preventing herpes zoster in adults. Here we present a comprehensive overview of the safety data from these studies. METHODS: Adults aged ≥50 (ZOE-50) and ≥70 (ZOE-70) years were randomly vaccinated with RZV or placebo. Safety analyses were performed on the pooled total vaccinated cohort, consisting of participants receiving at least one dose of RZV or placebo. Solicited and unsolicited adverse events (AEs) were collected for 7 and 30 days after each vaccination, respectively. Serious AEs (SAEs) were collected from the first vaccination until 12 months post-last dose. Fatal AEs, vaccination-related SAEs, and potential immune-mediated diseases (pIMDs) were collected during the entire study period. RESULTS: Safety was evaluated in 14,645 RZV and 14,660 placebo recipients. More RZV than placebo recipients reported unsolicited AEs (50.5% versus 32.0%); the difference was driven by transient injection site and solicited systemic reactions that were generally seen in the first week post-vaccination. The occurrence of overall SAEs (RZV: 10.1%; Placebo: 10.4%), fatal AEs (RZV: 4.3%; Placebo: 4.6%), and pIMDs (RZV: 1.2%; Placebo: 1.4%) was balanced between groups. The occurrence of possible exacerbations of pIMDs was rare and similar between groups. Overall, except for the expected local and systemic symptoms, the safety results were comparable between the RZV and Placebo groups irrespective of participant age, gender, or race. CONCLUSIONS: No safety concerns arose, supporting the favorable benefit-risk profile of RZV.

Primary care physicians' experience with zoster vaccine live (ZVL) and awareness and attitudes regarding the new recombinant zoster vaccine (RZV).

BACKGROUND: The Advisory Committee on Immunization Practices (ACIP) has routinely recommended zoster vaccine live (ZVL) for adults  ≥60 since 2008; only 33% of eligible adults received it by 2016. A recombinant zoster vaccine (RZV) was licensed in 2017 and ACIP recommended in January 2018. Our objectives were to assess among primary care physicians (1) practices and attitudes regarding ZVL and (2) awareness of RZV. METHODS: We administered an Internet and mail survey from July to September 2016 to national networks of 953 primary care physicians. RESULTS: Response rate was 65% (603/923). Ninety-three % of physicians recommended ZVL to adults ≥60, but fewer recommended it to adults ≥60 with a prior history of zoster (88%), adults > 85 (62%) and adults ≥60 on low-dose methotrexate (42%). Several physicians recommended ZVL in ways that are not recommended by ACIP including to adults 50-59 (50%), adults ≥60 with HIV (33%), and adults ≥60 on high dose prednisone (≥20 mg/day) (27%). Nineteen percent of physicians stocked and administered ZVL and did not refer patients elsewhere for vaccination, 37% did not stock and only referred patients to receive it, and 44% both stocked/administered and referred elsewhere. Twenty-three % (n = 115) of physicians who had ever administered ZVL in the office (n = 490) had stopped, citing primarily financial issues (90%). Only 5% were 'very aware' of RZV. CONCLUSIONS: Physicians report not recommending ZVL to certain ACIP-recommended groups, but report recommending it to some groups for which the vaccine should be avoided. Implementation of recommendations for RZV will need to consider financial barriers and the complex patchwork of office-based and pharmacy delivery ZVL has encountered.

Varicella-Zoster Virus DNA in Blood After Administration of Herpes Zoster Vaccine.

We studied the relationship between varicella-zoster virus (VZV) DNAemia and development of VZV-specific immunity after administration of live-attenuated zoster vaccine. VZV-DNAemia, detected by polymerase chain reaction (PCR), and VZV-specific effector (Teff) and memory (Tmem) T cells, was measured in 67 vaccinees. PCR was positive in 56% (9 direct, 28 nested) on day 1 and in 16% (1 direct, 10 nested) on day 14. Teff progressively increased in direct-PCR-positive vaccinees up to day 30, but Tmem did not. Conversely, Tmem, but not Teff, increased in direct-PCR-negative vaccinees on day 7. The kinetics of these immune responses and VZV DNAemia suggested that direct-PCR sample positive represented viremia.

A randomized lot-to-lot immunogenicity consistency study of the candidate zoster vaccine HZ/su.

BACKGROUND: The risk of developing herpes zoster (HZ) increases with age and is thought to be associated with a decrease in cell-mediated immunity in older adults. The adjuvanted varicella-zoster virus (VZV) glycoprotein E (gE) recombinant subunit vaccine (HZ/su) showed >90% efficacy in the prevention of HZ when administered in adults ≥50 years of age. Here we aim to evaluate immunogenicity consistency of 3 different HZ/su vaccine lots and to assess safety of these lots. METHODS: This multicenter, phase III, double-blind, randomized study (NCT02075515), assessed lot-to-lot consistency in terms of immunogenicity of HZ/su and also assessed safety of these lots. Participants aged 50 years or older were randomized (1:1:1) to receive 2 doses of HZ/su, 2 months apart, from 1 out of 3 randomized HZ/su lots (Lots A, B and C). Humoral immunogenicity was assessed pre-vaccination and 1 month post-second vaccination by anti-gE antibody enzyme-linked immunosorbent assay. Lot-to-lot consistency was demonstrated if the 2-sided 95% confidence intervals of the anti-gE geometric mean concentration ratio between all lot pairs were within 0.67 and 1.5. Solicited symptoms were recorded within 7 days and unsolicited adverse events (AEs) within 30 days after each vaccination. Serious AEs (SAEs) and potential immune-mediated diseases (pIMDs) were reported until study end (12 months post-second vaccination). RESULTS: Of 651 participants enrolled in the study, 638 received both doses of the HZ/su vaccine and 634 completed the study. Humoral immune responses were robust and consistency between 3 manufacturing lots was demonstrated. The incidence of solicited symptoms, unsolicited AEs and SAEs was comparable between all lots. Three fatal SAEs, 1 in each lot, were reported, none of which were considered vaccine-related by investigator assessment. Two out of the 8 reported pIMDs were considered vaccine-related by the investigator. CONCLUSION: The three HZ/su manufacturing lots demonstrated consistent immunogenicity. No safety concerns were identified. Clinical trial registry number: NCT02075515 (ClinicalTrials.gov).

Bioinformatics of varicella-zoster virus: single nucleotide polymorphisms define clades and attenuated vaccine genotypes.

Varicella zoster virus (VZV) is one of the human herpesviruses. To date, over 40 complete VZV genomes have been sequenced and analyzed. The VZV genome contains around 125,000 base pairs including 70 open reading frames (ORFs). Enumeration of single nucleotide polymorphisms (SNPs) has determined that the following ORFs are the most variable (in descending order): 62, 22, 29, 28, 37, 21, 54, 31, 1 and 55. ORF 62 is the major immediate early regulatory VZV gene. Further SNP analysis across the entire genome has led to the observation that VZV strains can be broadly grouped into clades within a phylogenetic tree. VZV strains collected in Singapore provided important sequence data for construction of the phylogenetic tree. Currently five VZV clades are recognized; they have been designated clades 1 through 5. Clades 1 and 3 include European/North American strains; clade 2 includes Asian strains, especially from Japan; and clade 5 includes strains from India. Clade 4 includes some strains from Europe, but its geographic origins need further documentation. Within clade 1, five variant viruses have been isolated with a missense mutation in the gE (ORF 68) glycoprotein; these strains have an altered increased cell spread phenotype. Bioinformatics analyses of the attenuated vaccine strains have also been performed, with a subsequent discovery of a stop-codon SNP in ORFO as a likely attenuation determinant. Taken together, these VZV bioinformatics analyses have provided enormous insights into VZV phylogenetics as well as VZV SNPs associated with attenuation.