Immunogenicity and safety of live attenuated and recombinant/inactivated varicella zoster vaccines in people living with HIV: A systematic review

Few papers focus their attention on VZV vaccination effectiveness among people living with HIV (PLWH). Flanking the live attenuated vaccine (VZL) available, a newly recombinant vaccine (RZV) was recently introduced and approved for HZ prevention among adults. PLWH represents a population on which a particular attention should be applied, in order to guarantee the vaccine efficacy and safety. We performed a literature search in USNLM, PubMed, PubMed Central, PMC and Cochrane Library. From all the publications found eligible, data were extracted and processed per population, vaccine type, immunogenicity and ADRs. The review of the 13 included studies shows that both RZV and VZL are immunogenic and have an acceptable safety profile in adults and children living with HIV. However, given the lack of research available about vaccine efficacy in preventing VZV and HZ in PLWH, additional studies need to be performed, in order to achieve a full completeness of data.

Associations of infections and vaccines with Alzheimer's disease point to a role of compromised immunity rather than specific pathogen in AD

INTRODUCTION

Diverse pathogens (viral, bacterial, fungal) have been associated with Alzheimer's disease (AD) and related traits in various studies. This suggests that compromised immunity, rather than specific microbes, may play a role in AD by increasing an individual's vulnerability to various infections, which could contribute to neurodegeneration. If true, then vaccines that have heterologous effects on immunity, extending beyond protection against the targeted disease, may hold a potential for AD prevention.

METHODS

We evaluated the associations of common adult infections (herpes simplex, zoster (shingles), pneumonia, and recurrent mycoses), and vaccinations against shingles and pneumonia, with the risks of AD and other dementias in a pseudorandomized sample of the Health and Retirement Study (HRS).

RESULTS

Shingles, pneumonia and mycoses, diagnosed between ages 65 and 75, were all associated with significantly increased risk of AD later in life, by 16 %-42 %. Pneumococcal and shingles vaccines administered between ages 65-75 were both associated with a significantly lower risk of AD, by 15 %-21 %. These effects became less pronounced when AD was combined with other dementias.

DISCUSSION

Our findings suggest that both the pneumococcal polysaccharide vaccine and the live attenuated zoster vaccine can offer significant protection against AD. It remains to be determined if non-live shingles vaccine has a similar beneficial effect on AD. This study also found significant associations of various infections with the risk of AD, but not with the risks of other dementias. This indicates that vulnerability to infections may play a more significant role in AD than in other types of dementia, which warrants further investigation.

Post-marketing surveillance of 10,392 herpes zoster vaccines doses in Australia

BACKGROUND

Immunisation against herpes zoster is recommended for adults aged ≥ 50 years. Two vaccines, a live attenuated (ZVL, Zostavax®) and an adjuvant recombinant subunit (HZ/su, Shingrix®), are available in Australia. Immunisation guidelines are shifting their recommendations towards HZ/su because of higher efficacy in preventing herpes zoster and associated complications. However, there are limited post-marketing data comparing the safety profiles of these vaccines.

METHODS

Data from SmartVax, an active surveillance system for monitoring adverse events following immunisation (AEFIs) utilised by > 450 clinics throughout Australia, were analysed. Data from patients aged ≥ 50 years, who received ZVL or HZ/su, from 1 June 2021 to 31 May 2022, at clinics that utilised SmartVax were included. The proportion of records where patients who reported any, local, and systemic AEFIs after receiving ZVL or HZ/su were compared using multivariable logistic regression models.

RESULTS

Data from 10,392 immunisation records (n = 8341 ZVL; n = 2051 HZ/su) were included. The proportion of AEFIs reported was higher with HZ/su (41.9 % [any], 33.8 % [local], 25.2 % [systemic]) than with ZVL (8.7 % [any], 6.2 % [local], 3.5 % [systemic]). After controlling for demographic variables, HZ/su presented a 6-fold increase in the odds (OR 6.44; 95 %CI: 5.57-7.46) of a reported AEFI compared to ZVL. Only 59 (0.6 %) of vaccinations lead to medical attention being sought due to an AEFI.

CONCLUSIONS

While rates of AEFIs was higher with HZ/su than ZVL, most AEFIs were mild and did not require medical attention. Our findings support the change in vaccine recommendations and the use of HZ/su in immunisation programs.

Crohn's Disease and Herpes Zoster: Being Mindful of Vaccination

Crohn's disease is a chronic inflammatory disease of the gastrointestinal tract. Immunosuppressive therapy is the main treatment modality in Crohn's disease. Herpes zoster (HZ), caused by Varicella-zoster virus, is a relatively common albeit burdensome clinical picture mainly affecting adult population with immunosuppressive status. In this paper, we aimed to report a Crohn's disease patient with HZ to raise awareness on vaccination. There are commercially available vaccines that are shown to be safe and effective against HZ reactivation. Crohn's disease patients should be evaluated and informed about preventive options against HZ to prevent unwanted HZ-related complications.

Vaccines for older adults

The proportion of the global population aged 65 and older is rapidly increasing. Infections in this age group, most recently with SARS-CoV-2, cause substantial morbidity and mortality. Major improvements have been made in vaccines for older people, either through the addition of novel adjuvants-as in the new recombinant zoster vaccine and an adjuvanted influenza vaccine-or by increasing antigen concentration, as in influenza vaccines. In this article we review improvements in immunization for the three most important vaccine preventable diseases of aging. The recombinant zoster vaccine has an efficacy of 90% that is minimally affected by the age of the person being vaccinated and persists for more than four years. Increasing antigen dose or inclusion of adjuvant has improved the immunogenicity of influenza vaccines in older adults, although the relative effectiveness of the enhanced influenza vaccines and the durability of the immune response are the focus of ongoing clinical trials. Conjugate and polysaccharide pneumococcal vaccines have similar efficacy against invasive pneumococcal disease and pneumococcal pneumonia caused by vaccine serotypes in older adults. Their relative value varies by setting, depending on the prevalence of vaccine serotypes, largely related to conjugate vaccine coverage in children. Improved efficacy will increase public confidence and uptake of these vaccines. Co-administration of these vaccines is feasible and important for maximal uptake in older people. Development of new vaccine platforms has accelerated following the arrival of SARS-CoV-2, and will likely result in new vaccines against other pathogens in the future.

Immunogenicity and safety of a live herpes zoster vaccine in hematopoietic stem cell transplant recipients

BACKGROUND

Herpes zoster (HZ) infection of hematopoietic stem cell transplant (HSCT) patients is of clinical concern. Vaccination could help restore immunity to varicella zoster virus (VZV); however, temporal changes in immunogenicity and safety of live HZ vaccines after HSCT is still unclear. The aim of this study was to elucidate the temporal immunogenicity and safety of the HZ vaccine according to time since HSCT and to determine optimal timing of vaccination.

METHODS

Live HZ vaccine was administered to patients 2-5 years or > 5 years post-HSCT. Control groups comprised patients with a hematologic malignancy who received cytotoxic chemotherapy and healthy volunteers. Humoral and cellular immunogenicity were measured using a glycoprotein enzyme-linked immunosorbent assay (gpELISA) and an interferon-γ (IFN-γ) enzyme-linked immunospot (ELISPOT) assay. Vaccine-related adverse events were also monitored.

RESULTS

Fifty-six patients with hematologic malignancy (41 in the HSCT group and 15 in the chemotherapy group) along with 30 healthy volunteers were enrolled. The geometric mean fold rises (GMFRs) in humoral immune responses of the 2-5 year and > 5 year HSCT groups, and the healthy volunteer group, were comparable and significantly higher than that of the chemotherapy group (3.15, 95% CI [1.96-5.07] vs 5.05, 95% CI [2.50-10.20] vs 2.97, 95% CI [2.30-3.83] vs 1.42, 95% CI [1.08-1.86]). The GMFR of cellular immune responses was highest in the HSCT 2-5 year group and lowest in the chemotherapy group. No subject suffered clinically significant adverse events or reactivation of VZV within the follow-up period.

CONCLUSION

Our findings demonstrate that a live HZ vaccine is immunogenic and safe when administered 2 years post-HSCT.

Recent Updates to the Advisory Committee On Immunization Practices Recommendations for Pneumococcal and Herpes Zoster Vaccination

Pneumococcal and herpes zoster - shingles - vaccination prevent a great deal of morbidity, particularly in elderly and immunocompromised hosts. Vaccination of children with conjugate pneumococcal vaccine in recent years has greatly reduced illness in older individuals as well. This article will review the historical and current recommendations for pneumococcal and herpes zoster vaccination and the rationale for changes at the level of the CDC's Advisory Committee on Immunization Practices.

Vaccines to Prevent Infectious Diseases in the Older Population: Immunological Challenges and Future Perspectives

Infectious diseases are a major cause for morbidity and mortality in the older population. Demographic changes will lead to increasing numbers of older persons over the next decades. Prevention of infections becomes increasingly important to ensure healthy aging for the individual, and to alleviate the socio-economic burden for societies. Undoubtedly, vaccines are the most efficient health care measure to prevent infections. Age-associated changes of the immune system are responsible for decreased immunogenicity and clinical efficacy of most currently used vaccines in older age. Efficacy of standard influenza vaccines is only 30-50% in the older population. Several approaches, such as higher antigen dose, use of MF59 as adjuvant and intradermal administration have been implemented in order to specifically target the aged immune system. The use of a 23-valent polysaccharide vaccine against Streptococcus pneumoniae has been amended by a 13-valent conjugated pneumococcal vaccine originally developed for young children several years ago to overcome at least some of the limitations of the T cell-independent polysaccharide antigens, but still is only approximately 50% protective against pneumonia. A live-attenuated vaccine against herpes zoster, which has been available for several years, demonstrated efficacy of 51% against herpes zoster and 67% against post-herpetic neuralgia. Protection was lower in the very old and decreased several years after vaccination. Recently, a recombinant vaccine containing the viral glycoprotein gE and the novel adjuvant AS01B has been licensed. Phase III studies demonstrated efficacy against herpes zoster of approx. 90% even in the oldest age groups after administration of two doses and many countries now recommend the preferential use of this vaccine. There are still many infectious diseases causing substantial morbidity in the older population, for which no vaccines are available so far. Extensive research is ongoing to develop vaccines against novel targets with several vaccine candidates already being clinically tested, which have the potential to substantially reduce health care costs and to save many lives. In addition to the development of novel and improved vaccines, which specifically target the aged immune system, it is also important to improve uptake of the existing vaccines in order to protect the vulnerable, older population.

Effect of Automated Immunization Registry-Based Telephonic Interventions on Adult Vaccination Rates in Community Pharmacies: A Randomized Controlled Trial

BACKGROUND

Pharmacies have a unique opportunity to address suboptimal adult vaccination rates, but few solutions have proven effective. Such strategies are challenged by the lack of access that many pharmacies have to a patient's complete immunization history; consequently, they are unable to identify which of their patients actually require vaccination. A pharmacy-based strategy that leverages such information could enhance efforts to increase rates of guideline-based vaccination.

OBJECTIVE

To determine the effect on vaccination rates of an automated telephonic intervention for adults in need of either pneumococcal vaccination or herpes zoster vaccination, or both.

METHODS

Over a 1-year period, patients with identified vaccine gaps at 246 pharmacies of 3 pharmacy chains were randomly assigned to receive either usual care or an automated telephonic prompt for pneumococcal and/or herpes zoster vaccines based on patient records contained in state immunization registries and pharmacy data. The primary outcome was the proportion with administration of at least one of the vaccines offered between March 2016 and January 2017 based on intention-to-treat principles. Subgroup analyses included vaccination rates by age and sex. An as-treated analysis was also performed.

RESULTS

21,971 patients were included in the study, 57% of whom were female, with a mean age of 63 years. Vaccine administration proportions were 0.0214 (236/11,009) in the intervention group, and 0.0205 (225/10,962) in the control group (OR = 1.05, 95% CI = 0.87-1.26). Results did not differ in subgroup analyses based on patient age, sex, or individual pharmacy chain. Among intervention patients, 3,666 (0.333) completed the call by listening to the entire prompt. In an as-treated analysis comparing individuals who completed calls versus control, the intervention increased the odds of vaccination by 26% (OR = 1.26, 95% CI = 1.00-1.61).

CONCLUSIONS

The automated prompt did not significantly increase vaccination rates. Potential barriers included intervention technical flaws, low rates of connecting with patients, insufficient follow-up by the pharmacy, and patients placing a relatively low priority on being vaccinated.

DISCLOSURES

This project was funded by Pfizer and Merck through a grant from the Pharmacy Quality Alliance. Stolpe was an employee of the Pharmacy Quality Alliance at the onset of this project and an employee of Scientific Technologies Corporation during the data collection phase of the project. Stolpe has also served on the advisory board for Merck. Choudhry has no conflicts of interest to declare.

Immunogenicity and safety of the adjuvanted recombinant zoster vaccine in adults with haematological malignancies: a phase 3, randomised, clinical trial and post-hoc efficacy analysis

BACKGROUND

The adjuvanted recombinant zoster vaccine (Shingrix) can prevent herpes zoster in older adults and autologous haemopoietic stem cell transplant recipients. We evaluated the safety and immunogenicity of this vaccine in adults with haematological malignancies receiving immunosuppressive cancer treatments.

METHODS

In this phase 3, randomised, observer-blind, placebo-controlled study, done at 77 centres worldwide, we randomly assigned (1:1) patients with haematological malignancies aged 18 years and older to receive two doses of the adjuvanted recombinant zoster vaccine or placebo 1-2 months apart during or after immunosuppressive cancer treatments, and stratified participants according to their underlying diseases. The co-primary objectives of the study were the evaluation of safety and reactogenicity of the adjuvanted recombinant zoster vaccine compared with placebo from the first vaccination up to 30 days after last vaccination in all participants; evaluation of the proportion of participants with a vaccine response in terms of anti-glycoprotein E humoral immune response to the adjuvanted recombinant zoster vaccine at month 2 in all participants, excluding those with non-Hodgkin B-cell lymphoma and chronic lymphocytic leukaemia; and evaluation of the anti-glycoprotein E humoral immune responses to the vaccine compared with placebo at month 2 in all participants, excluding those with non-Hodgkin B-cell lymphoma and chronic lymphocytic leukaemia. We assessed immunogenicity in the per-protocol cohort for immunogenicity and safety in the total vaccinated cohort. The study is registered with ClinicalTrials.gov, number NCT01767467, and with the EU Clinical Trials Register, number 2012-003438-18.

FINDINGS

Between March 1, 2013, and Sept 10, 2015, we randomly assigned 286 participants to adjuvanted recombinant zoster vaccine and 283 to placebo. 283 in the vaccine group and 279 in the placebo group were vaccinated. At month 2, 119 (80·4%, 95% CI 73·1-86·5) of 148 participants had a humoral vaccine response to adjuvanted recombinant zoster vaccine, compared with one (0·8%, 0·0-4·2) of 130 participants in the placebo group, and the adjusted geometric mean anti-glycoprotein E antibody concentration was 23 132·9 mIU/mL (95% CI 16 642·8-32 153·9) in the vaccine group and 777·6 mIU/mL (702·8-860·3) in the placebo group (adjusted geometric mean ratio 29·75, 21·09-41·96; p<0·0001) in all patients, excluding those with non-Hodgkin B-cell lymphoma and chronic lymphocytic leukaemia. Humoral and cell-mediated immune responses persisted above baseline until month 13 in all strata and, as expected, vaccine was more reactogenic than placebo (within 7 days after vaccination pain was reported by 221 [79·5%] of 278 vaccine group participants and 45 [16·4%] of 274 placebo group participants; fatigue was reported by 162 [58·3%] of 278 vaccine group participants and 102 [37·2%] of 274 placebo group participants). Incidences of unsolicited or serious adverse events, potential immune-mediated diseases, disease-related events, and fatal serious adverse events were similar between the groups.

INTERPRETATION

The immunocompromised adult population with haematological malignancies is at high risk for herpes zoster. The adjuvanted recombinant zoster vaccine, which is currently licensed in certain countries for adults aged 50 years and older, is likely to benefit this population.

FUNDING

GlaxoSmithKline Biologicals SA.

Updated insights into the mechanism of action and clinical profile of the immunoadjuvant QS-21: A review

BACKGROUND

Vaccine adjuvants are compounds that significantly enhance/prolong the immune response to a co-administered antigen. The limitations of the use of aluminium salts that are unable to elicite cell responses against intracellular pathogens such as those causing malaria, tuberculosis, or AIDS, have driven the development of new alternative adjuvants such as QS-21, a triterpene saponin purified from Quillaja saponaria.

PURPOSE

The aim of this review is to attempt to clarify the mechanism of action of QS-21 through either receptors or signaling pathways in vitro and in vivo with special emphasis on the co-administration with other immunostimulants in new adjuvant formulations, called adjuvant systems (AS). Furthermore, the most relevant clinical applications will be presented.

METHODS

A literature search covering the period 2014-2018 was performed using electronic databases from Sci finder, Science direct, Medline/Pubmed, Scopus, Google scholar.

RESULTS

Insights into the mechanism of action of QS-21 can be summarized as follows: 1) in vivo stimulation of Th2 humoral and Th1 cell-mediated immune responses through action on antigen presenting cells (APCs) and T cells, leading to release of Th1 cytokines participating in the elimination of intracellular pathogens. 2) activation of the NLRP3 inflammasome in mouse APCs with subsequent release of caspase-1 dependent cytokines, Il-1β and Il-18, important for Th1 responses. 3) synthesis of nearly 50 QS-21 analogs, allowing structure/activity relationships and mechanistic studies. 4) unique synergy mechanism between monophosphoryl lipid A (MPL A) and QS-21, formulated in a liposome (AS01) in the early IFN-γ response, promoting vaccine immunogenicity. The second part of the review is related to phase I-III clinical trials of QS-21, mostly formulated in ASs, to evaluate efficacy, immunogenicity and safety of adjuvanted prophylactic vaccines against infectious diseases, e.g. malaria, herpes zoster, tuberculosis, AIDS and therapeutic vaccines against cancer and Alzheimer's disease.

CONCLUSION

The most advanced phase III clinical applications led to the development of two vaccines containing QS-21 as part of the AS, the Herpes Zoster vaccine (HZ/su) (Shingrix™) which received a license in 2017 from the FDA and a marketing authorization in the EU in 2018 and the RTS,S/AS01 vaccine (Mosquirix™) against malaria, which was approved by the EMA in 2015 for further implementation in Sub-Saharan countries for routine use.

Medical conditions at enrollment do not impact efficacy and safety of the adjuvanted recombinant zoster vaccine: a pooled post-hoc analysis of two parallel randomized trials

In two pivotal efficacy studies (ZOE-50; ZOE-70), the adjuvanted recombinant zoster vaccine (RZV) demonstrated >90% efficacy against herpes zoster (HZ).Adults aged ≥50 or ≥70 years (ZOE-50 [NCT01165177]; ZOE-70 [NCT01165229]) were randomized to receive 2 doses of RZV or placebo 2 months apart. Vaccine efficacy and safety were evaluated post-hoc in the pooled (ZOE-50/70) population according to the number and type of selected medical conditions present at enrollment.At enrollment, 82.3% of RZV and 82.7% of placebo recipients reported ≥1 of the 15 selected medical conditions. Efficacy against HZ ranged from 84.5% (95% Confidence Interval [CI]: 46.4-97.1) in participants with respiratory disorders to 97.0% (95%CI: 82.3-99.9) in those with coronary heart disease. Moreover, efficacy remained >90% irrespective of the number of selected medical conditions reported by a participant.As indicated by the similarity of the point estimates, this post-hoc analysis suggests that RZV efficacy remains high in all selected medical conditions, as well as with increasing number of medical conditions. No safety concern was identified by the type or number of medical conditions present at enrollment.

Effectiveness of the herpes zoster vaccine Zostavax® in Stockholm County, Sweden

OBJECTIVE

The objective of this study was to estimate the effectiveness of the herpes zoster vaccine Zostavax in a cohort of vaccinated individuals in Sweden.

METHODS

The study is a retrospective population-based matched cohort study conducted with data from health care registers in Stockholm Country. Primary endpoints were new diagnosis of HZ after administration of Zostavax. Individuals above the age of 50 years and living in Stockholm County in 2013 were included into the study. Ten non-vaccinated individuals per vaccinated were included and randomized into the cohort. The non-vaccinated were matched on age at index date and gender.

RESULTS

Zostavax had an overall effectiveness (VE) of 34% (HR = 0.66, 95% CI: 0.55-0.78). When stratifying by age, 61-75 years was the only age group that showed a reduced risk of HZ (HR = 0.57; CI 0.44-0.73) compared to those that were non-vaccinated. As compared to the unvaccinated group, the VE was significant at days 180-359 (HR = 0.53; 95% CI 0.33-0.88), 360-539 (HR = 0.46; 95% CI 0.27-0.80) and at days 540-719 (HR = 0.56; 95% CI 0.35-0.90) after vaccination.

CONCLUSION

This is the first population-based study in Sweden studying the effectiveness of HZ vaccination. Our findings are well in-line with previous studies, however studies addressing the longitudinal efficacy and effectiveness of Zostavax are still required.

Immunogenicity and safety of the adjuvanted recombinant zoster vaccine in patients with solid tumors, vaccinated before or during chemotherapy: A randomized trial

BACKGROUND

The adjuvanted recombinant zoster vaccine (RZV) has demonstrated >90% efficacy against herpes zoster in adults ≥50 years of age and 68% efficacy in autologous hematopoietic stem cell transplant recipients ≥18 years of age. We report the immunogenicity and safety of RZV administered to patients with solid tumors (STs) before or at the start of a chemotherapy cycle.

METHOD

In this phase 2/3 observer-blind, multicenter study (NCT01798056), patients with STs who were ≥18 years of age were randomized (1:1) to receive 2 doses of RZV or placebo 1-2 months apart and stratified (4:1) according to the timing of the first dose with respect to the start of a chemotherapy cycle (first vaccination 8-30 days before the start or at the start [±1 day] of a chemotherapy cycle). Anti-glycoprotein E (gE) antibody concentrations, gE-specific CD4+ T cell frequencies, and vaccine response rates (VRRs) were assessed 1 month after dose 1 and 1 and 12 months after dose 2. Reactogenicity and safety were assessed in the total vaccinated cohort through 12 months after dose 2.

RESULTS

There were 232 participants in the total vaccinated cohort, 185 participants in the according-to-protocol cohort for humoral immunogenicity, and 58 participants in the according-to-protocol cohort for cell-mediated immunogenicity. Postvaccination anti-gE antibody concentrations, gE-specific CD4+ T cell frequencies and VRRs were higher in RZV recipients than in placebo recipients. Solicited adverse events (AEs) were more frequent among RZV recipients than placebo recipients. Incidence of unsolicited AEs, serious AEs, fatalities, and potential immune-mediated diseases were similar between RZV and placebo recipients.

CONCLUSION

RZV was immunogenic in patients with STs receiving immunosuppressive chemotherapies. Humoral and cell-mediated immune responses persisted 1 year after vaccination. No safety concerns were identified.

An ODE-based mixed modelling approach for B- and T-cell dynamics induced by Varicella-Zoster Virus vaccines in adults shows higher T-cell proliferation with Shingrix than with Varilrix

Clinical trials covering the immunogenicity of a vaccine aim to study the longitudinal dynamics of certain immune cells after vaccination. The corresponding immunogenicity datasets are mainly analyzed by the use of statistical (mixed effects) models. This paper proposes the use of mathematical ordinary differential equation (ODE) models, combined with a mixed effects approach. ODE models are capable of translating underlying immunological post vaccination processes into mathematical formulas thereby enabling a testable data analysis. Mixed models include both population-averaged parameters (fixed effects) and individual-specific parameters (random effects) for dealing with inter- and intra-individual variability, respectively. This paper models B-cell and T-cell datasets of a phase I/II, open-label, randomized, parallel-group study (NCT00492648) in which the immunogenicity of a new Herpes Zoster vaccine (Shingrix) is compared with the original Varicella Zoster Virus vaccine (Varilrix). Since few significant correlations were found between the B-cell and T-cell datasets, each dataset was modeled separately. By following a general approach to both the formulation of several different models and the procedure of selecting the most suitable model, we were able to propose a mathematical ODE mixed-effects model for each dataset. As such, the use of ODE-based mixed effects models offers a suitable framework for handling longitudinal vaccine immunogenicity data. Moreover, this approach allows testing for differences in immunological processes between vaccines or schedules. We found that the Shingrix vaccination schedule led to a more pronounced proliferation of T-cells, without a difference in T-cell decay rate compared to the Varilrix vaccination schedule.

Understanding the immunology of the Zostavax shingles vaccine

Zostavax is a live-attenuated varicella zoster virus (VZV) vaccine recommended for use in adults >50 years of age to prevent shingles. The main risk factor for the development of shingles is age, which correlates with decreasing cell-mediated immunity. These data suggest a predominant role of T cell immunity in controlling VZV latency. However, other components of the immune system may also contribute. In this review, we will discuss how the immune system responds to Zostavax, focusing on recent studies examining innate immunity, transcriptomics, metabolomics, cellular, and humoral immunity.

Calabria: a successful experience implementing Herpes Zoster vaccination strategies

Recently, the National Immunization Plan (NIP) in Italy has highlighted the importance of immunization practices also for adults, including vaccinations against influenza, Pneumococcus (PNO) and HZ. In response to the NIP, the Calabria region decided to offer HZ vaccination to the two cohorts of 65- and 70-year-old subjects. We at the Reggio Calabria Local Health Services, concentrated our efforts on addressing all the above-mentioned shortcomings and, as a first measure, we addressed the convenience problem by scheduling the HZ vaccine administration during the same visit as the pneumococcal vaccination (PCV13 vaccine). The adhesion rates were satisfactory in both cohorts-such high levels of vaccine coverage for HZ and PCV13 had never been reached before in our region and are still among the highest in Italy. However, the main result was undoubtedly the significantly high rate of PCV13 and HZ vaccine co-administration without safety problems.

Altered immunogenicity of 23-valent pneumococcal polysaccharide vaccine in elderly patients with diabetes who revealed lower responses to concomitant administration of BIKEN varicella zoster vaccine: Results of post hoc analysis of a randomized double-blind trial

AIMS

This double-blind randomized controlled study of 52 elderly patients with diabetes assessed cell-mediated immunity and safety of BIKEN varicella-zoster vaccine (BVZV). Cellular and humoral responses to VZV at 3 months after BVZV and 23-valent polysaccharide pneumococcal vaccine (PPSV23) vaccination elicited poor results. Post-hoc analyses assessed the effects of immunogenicity of PPSV23.

METHODS

Using standardized enzyme-linked immunosorbent assay, pneumococcal 6B and 23F serotype-specific immunoglobulin G (IgG)-binding antibody concentrations were measured in stored samples retrospectively before administration and 3 months after. Responders increased more than twofold in at least one serotype-specific IgG.

RESULTS

The geometric mean concentration ratio (GMCR) of serum anti-pneumococcal 6B IgG was 1.76 (95%C.I.: 0.58, 5.34) in patients receiving concurrent PPSV23 and BVZV, compared to 2.39 (95%C.I.: 0.53, 10.76) in patients receiving PPSV23 and placebo (P = .055). The GMCR of serum anti-pneumococcal 23F IgG was 2.54 (95%C.I.: 0.57, 11.43) in PPSV23/BVZV vaccinees compared to 3.34 (95%C.I.: 0.84, 12.92) in PPSV23/placebo vaccinees (P = .424). Responder rates, those who developed antibodies to either/both serotypes, were 68% in the BVZV group and 85% in the placebo group (P = .007).

CONCLUSIONS

Results suggest that concurrent administration of BVZV influenced humoral responses to PPSV23 in elderly subjects with diabetes.

Long-term study showed that vaccination protected paediatric renal transplant recipients from life-threatening varicella zoster virus

AIM

Renal transplant patients are particularly susceptible to highly contagious diseases due to their reduced immunity. We studied transplant recipients to gauge their varicella zoster virus (VZV) serology status over time and the outcome of any VZV infections.

METHOD

This retrospective study comprised 85 children who underwent renal transplants in Gothenburg, Sweden, from 1986 to 2014, at a mean age of eight (1-18) years. The children's medical records were reviewed and 47 had the VZV infection pre-transplant and 38 had been vaccinated pre-transplant. Clinical outcomes were available for 85 children and serology results for 72.

RESULTS

At transplantation, the VZV seropositivity rate was 50% in the vaccination group and 94% in the infection group and the antibody titres were significantly lower in the vaccination group (p = 0.031). During the median follow-up period of five years post-transplant, 28% of the vaccinated children and 97% of the infection group remained seropositive and the varicella infection affected eight children: one in the infection group and seven in the vaccination group. The herpes zoster was observed in two children in the infection group.

CONCLUSION

This study demonstrated that VZV vaccination protected from symptomatic infections to a lesser extent than natural infection, but provided effective protection from life-threatening disease.

Safety and Immunogenicity of Zoster Vaccine Live in Human Immunodeficiency Virus-Infected Adults With CD4+ Cell Counts >200 Cells/mL Virologically Suppressed on Antiretroviral Therapy

Background

Herpes zoster (HZ) risk is increased in human immunodeficiency virus (HIV)-infected persons. Live attenuated zoster vaccine (ZV) reduces HZ incidence and severity in adults; safety and immunogenicity data in HIV-infected adults are limited.

Methods

We conducted a randomized, double-blind, placebo-controlled trial in HIV-infected adults virally suppressed on antiretroviral therapy (ART). Participants, stratified by CD4+ count (200-349 or ≥350 cells/µL), were randomized 3:1 to receive ZV or placebo on day 0 and week 6. The primary endpoint was serious adverse event or grade 3/4 signs/symptoms within 6 weeks after each dose. Immunogenicity (varicella zoster virus [VZV]-specific glycoprotein enzyme-linked immunosorbent assay and interferon-γ enzyme-linked immunospot assay responses) was assessed at 6 and 12 weeks postvaccination.

Results

Of 395 participants (296 ZV vs 99 placebo), 84% were male, 47% white, 29% black, and 22% Hispanic; median age was 49 years. Safety endpoints occurred in 15 ZV and 2 placebo recipients (5.1% [95% confidence interval {CI}, 2.9%-8.2%] vs 2.1% [95% CI, .3%-7.3%]; P = .26). Injection site reactions occurred in 42% of ZV (95% CI, 36.3%-47.9%) vs 12.4% of placebo recipients (95% CI, 6.6%-20.6%) (P < .001). Week 12 median natural log VZV antibody titer was higher for ZV (6.30 [Q1, Q3, 5.64, 6.96]) vs placebo (5.48 [Q1, Q3, 4.63, 6.44]; P < .001) overall and in the high CD4+ stratum (P = .003). VZV antibody titers were similar after 1 or 2 ZV doses. Polymerase chain reaction-confirmed HZ occurred in 2 participants (1 ZV; 1 placebo); none was vaccine strain related.

Conclusions

Two doses of ZV in HIV-infected adults suppressed on ART with CD4+ counts ≥200 cells/µL were safe and immunogenic.

Clinical Trials Registration

NCT00851786.

Assessing the effectiveness of zoster vaccine live: A retrospective cohort study using primary care data in the United Kingdom

BACKGROUND

Herpes zoster (shingles) is a common viral disease increasing in risk and severity with age. Post-herpetic neuralgia (PHN), a complication of shingles, causes severe pain impacting quality of life (QoL). Zoster Vaccine Live (ZVL), a licensed vaccine for the prevention of shingles in the United Kingdom (UK), is part of the national immunisation programme (NIP) for adults aged 70-79. Public Health England (PHE) reports show shingles vaccine coverage varies, but is typically 50-60% across eligible cohorts.

MATERIALS/METHODS

This retrospective, matched cohort study was conducted using The Health Improvement Network (THIN) UK primary care database. Individuals aged 70-79 were classified based on their vaccination status between September 2013 and May 2016. Risk and incidence rates for shingles were calculated for both groups over the duration of the study (mean 1.2 years). Vaccine effectiveness (VE) was calculated using the equation 1-relative risk (RR) for shingles and PHN.

RESULTS

Within the total cohort (n = 295,135), 70,867 (24%) were vaccinated and 224,268 (76%) were unvaccinated. 2435 (0.83%) patients developed shingles: 241 (0.34%) among the vaccinated and 2194 (0.98%) among the unvaccinated. The VE for preventing shingles was 65.3% (95% CI: 60.3-69.6%). The incidence rate in the vaccinated group was 2.95 (95% CI: 2.59-3.34) vs 8.02 (95% CI: 7.68-8.36) per 1000 person years in the unvaccinated group. Risk of PHN was 0.02% and 0.06% in the respective vaccinated and unvaccinated groups. The VE for preventing PHN was 72% (95% CI: 50.0-83.9%). PHN incidence rates were 0.16 (95% CI: 0.08-0.27) and 0.53 (95% CI: 0.44-0.62) per 1000 person years in the vaccinated and unvaccinated groups, respectively.

CONCLUSIONS

ZVL reduced the risk of shingles among an elderly population. Given the negative impact of shingles and PHN on QoL, the benefits of vaccination are clear. Improving uptake in the UK is needed in this population.

Effectiveness of herpes zoster vaccination in an older United Kingdom population

BACKGROUND

Vaccination against herpes zoster was introduced in the United Kingdom in 2013 for individuals aged 70 years, with a phased catch-up campaign for 71-79 year olds. Vaccine introduction has resulted in a marked fall in incident herpes zoster and in post-herpetic neuralgia (PHN), but formal evaluation of vaccine effectiveness is needed.

METHODS

In a population-based cohort study of older individuals born between 1933 and 1946, we used linked UK anonymised primary care health records for the first three years of the vaccination programme (01/09/2013-31/08/2016) and multivariable Poisson regression to obtain incidence rates and vaccine effectiveness (VE) against zoster and PHN.

RESULTS

Among 516,547 individuals, 21% were vaccinated. Incidence of zoster was 3.15/1000 person-years in vaccinees and 8.80/1000 person-years in unvaccinated individuals. After adjustment, VE was 64% (95%CI = 60-68%) against incident zoster and 81% (95%CI = 61-91%) against PHN, with very similar VE estimates in the routine and catch-up cohorts. VE against zoster was lower in those with a previous history of zoster: 47% (95%CI = 31-58%) versus 64% (95%CI = 60-68%) in those without previous zoster. There was evidence of waning VE over time, from 69% (95%CI = 65-74%) in the first year after vaccination to 45% (95%CI = 29-57%) by the third year.

CONCLUSION

This first formal assessment of VE in the UK zoster vaccination programme demonstrates good effectiveness of zoster vaccine, and very good protection against PHN. The findings provide evidence that VE is similar across the age groups targeted for vaccination in the UK, and on duration of protection of the vaccine in public health use. The study provides key information for decision-makers about the future direction of UK zoster vaccination programme, indicating that the live zoster vaccine may be more cost-effective than estimated previously. It also supports efforts to communicate the benefits of zoster vaccination to address the declining coverage observed across the UK.

Varicella Virus Vaccination in the United States

Varicella zoster virus (VZV) is the cause of chickenpox (varicella) and shingles (zoster), and was once responsible for over 4 million infections in the United States annually. The development of a live attenuated VZV vaccine was initially viewed with extreme skepticism. Nonetheless, a VZV vaccine was developed in the 1970s by Takahashi and his colleagues in Japan and was eventually licensed in the US. It is now known to be one of the safest and most effective vaccines available and is administered worldwide. Here are described important factors that contributed to the successful research and licensure of the highly successful VZV vaccine.

Vaccinations in adults with rheumatoid arthritis in an era of new disease-modifying anti-rheumatic drugs

Patients with rheumatoid arthritis are at greater risk of infectious morbidity and mortality due to disease-related abnormalities and use of immunosuppressive medications. Vaccinations are recommended by international guidelines among infection control strategies, but vaccination rates are reported to be still suboptimal in both America and Europe. Furthermore, with the increasing number of immunomodulatory medications used in RA patients, safety and efficacy of vaccinations in RA patients on such therapies have been questioned. This paper reviews current data about the safety of the most relevant vaccinations for RA adult patients and on the extent to which RA treatment can affect vaccine efficacy. Although it is recognised that immunological and pathological reactions can occur following vaccination, especially in genetically susceptible hosts, early data in RA patients under treatment with bDMARDs or tsDMARDs indicate that vaccines might be safer in the setting of immunosuppression than previously thought. Reviewing safety and immunogenicity data about influenza, pneumococcal, HZ, HPV, and HBV vaccines, we here try to summarise updated, practical suggestions for rheumatologists. Improving the knowledge of the vaccination practice both in patients and physicians is of crucial importance. In RA patients, vaccination status should be assessed in the initial patients' work-up and vaccination strategies should be planned and then implemented ideally during stable disease, as recommended by international guidelines.

Modeling the impact of combined vaccination programs against varicella and herpes zoster in Norway

BACKGROUND

Adoption of varicella immunization in Europe is limited due to a predicted increase in the incidence of herpes zoster (HZ) resulting from a removal of exogenous boosting by varicella vaccination. Most available assessments of immunization strategies only considered universal varicella vaccination (alone or in combination with HZ by the live vaccine). The development of a new subunit recombinant zoster vaccine may provide new perspectives of HZ control.

METHODS

We used a mathematical model for VZV in Norway based on the progressive immunity formulation of exogenous boosting. We evaluated a complete range of alternative immunization options against varicella and HZ including both universal and targeted varicella vaccination, either alone or with zoster immunization, and zoster immunization alone. We considered all values of the boosting intensity consistent with the Norwegian HZ incidence and compared the performance of the currently available live vaccine vs. a new recombinant vaccine.

RESULTS

Universal varicella vaccination alone resulted in a marked increase in the incidence of HZ under all scenarios considered. Even under the most favorable hypotheses on the magnitude of the boosting intensity, this increase could be mitigated only by a parallel HZ immunization with a recombinant vaccine, assuming a long duration of protection. Targeted varicella immunization of adolescents resulted in a modest increase in the HZ incidence which could be counterbalanced by both the live and, especially, the recombinant vaccine.

CONCLUSIONS

Given current knowledge on HZ pathogenesis and exogenous boosting, targeted varicella vaccination of adolescents was the only strategy that was not predicted to impact the epidemiology of HZ, and therefore it may represent a suitable alternative to universal vaccination. These results are aimed to support vaccine policy decisions in Norway and other countries with a similar VZV epidemiology.

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).

The Safety and Immunogenicity of Live Zoster Vaccination in Patients With Rheumatoid Arthritis Before Starting Tofacitinib: A Randomized Phase II Trial

OBJECTIVE

Patients with rheumatoid arthritis (RA) are at increased risk of herpes zoster, and vaccination is recommended for patients ages 50 years and older, prior to starting treatment with biologic agents or tofacitinib. Tofacitinib is an oral JAK inhibitor for the treatment of RA. We evaluated its effect on the immune response and safety of live zoster vaccine (LZV).

METHODS

In this phase II, 14-week, placebo-controlled trial, patients ages 50 years and older who had active RA and were receiving background methotrexate were given LZV and randomized to receive tofacitinib 5 mg twice daily or placebo 2-3 weeks postvaccination. We measured humoral responses (varicella zoster virus [VZV]-specific IgG level as determined by glycoprotein enzyme-linked immunosorbent assay) and cell-mediated responses (VZV-specific T cell enumeration, as determined by enzyme-linked immunospot assay) at baseline and 2 weeks, 6 weeks, and 14 weeks postvaccination. End points included the geometric mean fold rise (GMFR) in VZV-specific IgG levels (primary end point) and T cells (number of spot-forming cells/106 peripheral blood mononuclear cells) at 6 weeks postvaccination.

RESULTS

One hundred twelve patients were randomized to receive tofacitinib (n = 55) or placebo (n = 57). Six weeks postvaccination, the GMFR in VZV-specific IgG levels was 2.11 in the tofacitinib group and 1.74 in the placebo group, and the VZV-specific T cell GMFR was similar in the tofacitinib group and the placebo group (1.50 and 1.29, respectively). Serious adverse events occurred in 3 patients in the tofacitinib group (5.5%) and 0 patients (0.0%) in the placebo group. One patient, who lacked preexisting VZV immunity, developed cutaneous vaccine dissemination 2 days after starting tofacitinib (16 days postvaccination). This resolved after tofacitinib was discontinued and the patient received antiviral treatment.

CONCLUSION

Patients who began treatment with tofacitinib 2-3 weeks after receiving LZV had VZV-specific humoral and cell-mediated immune responses to LZV similar to those in placebo-treated patients. Vaccination appeared to be safe in all of the patients except 1 patient who lacked preexisting VZV immunity.

Protocol of a randomised controlled trial characterising the immune responses induced by varicella-zoster virus (VZV) vaccination in healthy Kenyan women: setting the stage for a potential VZV-based HIV vaccine

INTRODUCTION

A protective HIV vaccine would be expected to induce durable effector immune responses at the mucosa, restricting HIV infection at its portal of entry. We hypothesise that use of varicella-zoster virus (VZV) as an HIV delivery vector could generate sustained and robust tissue-based immunity against HIV antigens to provide long-term protection against HIV. Given that HIV uniquely targets immune-activated T cells, the development of human vaccines against HIV must also involve a specific examination of the safety of the vector. Thus, we aim to evaluate the effects of VZV vaccination on the recipients' immune activation state, and on VZV-specific circulating humoral and cellular responses in addition to those at the cervical and rectal mucosa.

METHODS AND ANALYSIS

This open-label, randomised, longitudinal crossover study includes healthy Kenyan VZV-seropositive women at low risk for HIV infection. Participants receive a single dose of a commercial live-attenuated VZV_Oka vaccine at either week 0 (n=22) or at week 12 (n=22) of the study and are followed for 48 and 36 weeks postvaccination, respectively. The primary outcome is the change on cervical CD4⁺ T-cell immune activation measured by the coexpression of CD38 and HLA-DR 12 weeks postvaccination compared with the baseline (prevaccination). Secondary analyses include postvaccination changes in VZV-specific mucosal and systemic humoral and cellular immune responses, changes in cytokine and chemokine measures, study acceptability and feasibility of mucosal sampling and a longitudinal assessment of the bacterial community composition of the mucosa.

ETHICS AND DISSEMINATION

The study has ethical approval from Kenyatta National Hospital/University of Nairobi Ethics and Research Committee, the University of Toronto Research Ethics Board and by Kenyan Pharmacy and Poisons Board. Results will be presented at conferences, disseminated to participants and stakeholders as well as published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02514018. Pre-results.

Is chickenpox so bad, what do we know about immunity to varicella zoster virus, and what does it tell us about the future?

Varicella and zoster continue to cause significant morbidity and even mortality in children and adults. Complications include bacterial superinfection, central nervous system manifestations such as meningitis, encephalitis, and cerebellar ataxia, and pain syndromes especially post herpetic neuralgia. Many developed countries but not all, are now administering live attenuated varicella vaccine routinely, with a decrease in the incidence of disease, providing personal and herd immunity. There is some controversy, however, in some countries concerning whether a decrease in the circulation of wild type virus will result in loss of immunity to VZV in persons who have already had varicella. This manuscript reviews the complications of varicella and zoster in detail, the reasons for development of vaccines against these diseases, complications of vaccinations, and mechanisms by which immunity to this virus develops and is maintained. There are strong indications that the best way to control disease and spread of this virus is by vaccination against both.

Prevention of Herpes Zoster and its complications: From clinical evidence to real life experience

Herpes zoster (HZ) is an acute viral illness characterized by a vesicular rash with unilateral distribution, which can also result in severe complications such as post-herpetic neuralgia (PHN), ophthalmic zoster, stroke or other neurological complications. The estimate incidence in Europe ranges between 2.0 and 4.6 cases per 1,000 person-years, with a sharp increase in >50 year-old subjects. Currently, treatment options for HZ are only partially effective in limiting the acute phase, while the management of complications is complex and often unsatisfactory. The total burden of the disease and the high costs related to its diagnostic and therapeutic management led researchers to develop a new preventive approach through a live attenuated virus vaccine. The currently available vaccine, with a high antigen content, is safe, well tolerated and reduces the incidence of HZ, PHN and the burden of illness. Several countries have introduced this vaccination, albeit with different recommendations and methods of financing. Taking into account the barriers to this immunization registered in some areas (difficulty of vaccine distribution, lack of physician recommendations, the cost of vaccine for patients, etc.), this group of Italian experts advocate that a common strategy able to guarantee a good compliance with this vaccination should be implemented. The same group addresses some practical questions concerning the use of zoster vaccine.

Defective T Memory Cell Differentiation after Varicella Zoster Vaccination in Older Individuals

Vaccination with attenuated live varicella zoster virus (VZV) can prevent zoster reactivation, but protection is incomplete especially in an older population. To decipher the molecular mechanisms underlying variable vaccine responses, T- and B-cell responses to VZV vaccination were examined in individuals of different ages including identical twin pairs. Contrary to the induction of VZV-specific antibodies, antigen-specific T cell responses were significantly influenced by inherited factors. Diminished generation of long-lived memory T cells in older individuals was mainly caused by increased T cell loss after the peak response while the expansion of antigen-specific T cells was not affected by age. Gene expression in activated CD4 T cells at the time of the peak response identified gene modules related to cell cycle regulation and DNA repair that correlated with the contraction phase of the T cell response and consequently the generation of long-lived memory cells. These data identify cell cycle regulatory mechanisms as targets to reduce T cell attrition in a vaccine response and to improve the generation of antigen-specific T cell memory, in particular in an older population.

Efficacy of the Herpes Zoster Subunit Vaccine in Adults 70 Years of Age or Older

BACKGROUND

A trial involving adults 50 years of age or older (ZOE-50) showed that the herpes zoster subunit vaccine (HZ/su) containing recombinant varicella-zoster virus glycoprotein E and the AS01B adjuvant system was associated with a risk of herpes zoster that was 97.2% lower than that associated with placebo. A second trial was performed concurrently at the same sites and examined the safety and efficacy of HZ/su in adults 70 years of age or older (ZOE-70).

METHODS

This randomized, placebo-controlled, phase 3 trial was conducted in 18 countries and involved adults 70 years of age or older. Participants received two doses of HZ/su or placebo (assigned in a 1:1 ratio) administered intramuscularly 2 months apart. Vaccine efficacy against herpes zoster and postherpetic neuralgia was assessed in participants from ZOE-70 and in participants pooled from ZOE-70 and ZOE-50.

RESULTS

In ZOE-70, 13,900 participants who could be evaluated (mean age, 75.6 years) received either HZ/su (6950 participants) or placebo (6950 participants). During a mean follow-up period of 3.7 years, herpes zoster occurred in 23 HZ/su recipients and in 223 placebo recipients (0.9 vs. 9.2 per 1000 person-years). Vaccine efficacy against herpes zoster was 89.8% (95% confidence interval [CI], 84.2 to 93.7; P<0.001) and was similar in participants 70 to 79 years of age (90.0%) and participants 80 years of age or older (89.1%). In pooled analyses of data from participants 70 years of age or older in ZOE-50 and ZOE-70 (16,596 participants), vaccine efficacy against herpes zoster was 91.3% (95% CI, 86.8 to 94.5; P<0.001), and vaccine efficacy against postherpetic neuralgia was 88.8% (95% CI, 68.7 to 97.1; P<0.001). Solicited reports of injection-site and systemic reactions within 7 days after injection were more frequent among HZ/su recipients than among placebo recipients (79.0% vs. 29.5%). Serious adverse events, potential immune-mediated diseases, and deaths occurred with similar frequencies in the two study groups.

CONCLUSIONS

In our trial, HZ/su was found to reduce the risks of herpes zoster and postherpetic neuralgia among adults 70 years of age or older. (Funded by GlaxoSmithKline Biologicals; ZOE-50 and ZOE-70 ClinicalTrials.gov numbers, NCT01165177 and NCT01165229 .).

Efficacy and safety of live varicella zoster vaccine in diabetes: a randomized, double-blind, placebo-controlled trial

AIMS

To elucidate varicella zoster virus (VZV)-specific cell-mediated immunity and humoral immunogenicity against live attenuated Oka varicella zoster vaccine concurrently vaccinated with 23-valent pneumococcal polysaccharide vaccine (PPSV23) in elderly people with diabetes mellitus.

METHODS

This double-blind randomized controlled single-centre study of 60-70-year-old people with diabetes compared immunity and safety profiles 3 months after one dose of varicella zoster vaccine or placebo. PPSV23 was immunized simultaneously. Primary analysis evaluated cell-mediated immunity using the VZV skin test. Secondary analyses were a VZV interferon-γ enzyme-linked immunospot (ELISPOT) assay and immunoadherence haemagglutination test. Adverse experiences were recorded using diary questionnaires.

RESULTS

By intent-to-treat analysis, 27 participants with diabetes who had been administered the vaccine were compared with 27 participants who were given a placebo. Changes in skin test scores were 0.41 ± 0.80 and 0.11 ± 0.93 (P = 0.2155), and geometric mean fold rises of the ELISPOT counts were 1.2 [95% confidence interval (CI) 0.2, 7.9] and 1.2 (95% CI 0.2, 7.3) (P = 0.989) in the vaccine and placebo groups, respectively. The geometric mean titre did not increase 3 months after vaccination in either group. No vaccination-related severe adverse experience was reported and no participant developed herpes zoster.

DISCUSSION

Our previous results demonstrated that varicella zoster vaccine safely enhanced VZV-specific immunity in elderly people with or without diabetes. The results of this study showed that varicella zoster vaccine can be used safely, but it cannot boost virus-specific immunity in elderly people with diabetes when administered with concurrent PPSV23. Alternative strategies are needed to prevent VZV-associated diseases in this population.

Immunogenicity and Safety of a Live Attenuated Zoster Vaccine (ZOSTAVAX™) in Korean Adults

A live attenuated zoster vaccine (ZOSTAVAX™, Merck & Co., Inc.) was approved by the Korea Ministry of Food and Drug Safety in 2009. However, the immunogenicity and safety of the vaccine has not been assessed in Korean population. This is multi-center, open-label, single-arm study performed with 180 healthy Korean adults ≥ 50 yr of age. The geometric mean titer (GMT) and geometric mean fold rise (GMFR) of varicella zoster virus (VZV) antibodies were measured by glycoprotein enzyme-linked immunosorbent assay (gpELISA) at 4 weeks post-vaccination. Subjects were followed for exposure to varicella or herpes zoster (HZ), the development of any varicella/varicella-like or HZ/HZ-like rashes, and any other clinical adverse experiences (AEs) for 42 days post-vaccination. For the 166 subjects included in the per-protocol population, the GMT at Day 1 was 66.9. At 4 weeks post-vaccination, the GMT for this population was 185.4, with a GMFR of 2.8 (95% CI, 2.5-3.1). Of the 180 subjects vaccinated, 62.8% experienced ≥ 1 AE, with 53.3% of subjects reporting injection-site AEs. The most frequently reported injection-site AEs were erythema (45.0%) with the majority being mild in intensity. Overall, 44 (24.4%) subjects experienced ≥ 1 systemic AE, 10 (5.5%) subjects experienced a systemic vaccine-related AE, and 3 (1.7%) subjects experienced ≥ 1 serious AE not related to vaccine. No subjects reported a VZV-like rash. There was no subject of death and no subject discontinued due to an adverse event. A single dose of zoster vaccine induced VZV-specific gpELISA antibody response and was generally well-tolerated in healthy Korean adults ≥50 yr of age (registry at www.clinicaltrial.gov No. NCT01556451).

Herpes Zoster Vaccine in the Long-Term Care Setting: A Clinical and Logistical Conundrum

Advancing age is associated with an increased risk of herpes zoster (shingles) infection and latent effects such as postherpetic neuralgia. The herpes zoster vaccine is recommended in those 60 years of age and older and has been shown to prevent both the primary disease and associated complications. While this recommendation applies to those living in long-term care facilities, there is little clinical evidence to support use in this population. Additionally, there are logistical barriers that may complicate the use of the vaccine. The article examines the evidence for vaccinating residents in long-term care facilities and discusses logistical barriers to vaccination. Pharmacists and providers may consider life expectancy and other factors when evaluating which patients should receive the vaccination.

Long-term immunogenicity and safety of an investigational herpes zoster subunit vaccine in older adults

BACKGROUND

An investigational subunit vaccine containing the varicella-zoster virus (VZV) glycoprotein E (gE) and the AS01B adjuvant system is being evaluated for the prevention of herpes zoster (HZ) in older adults. A phase II trial evaluating different formulations of this vaccine (containing 25μg, 50μg, or 100μg gE) was conducted in adults ≥60 years of age and showed that all formulations elicited robust cellular and humoral immune responses for up to 3 years after vaccination. In this follow-up study in subjects who received two doses of the 50μg gE/AS01B formulation (HZ/su), we assessed the persistence of the immune responses for up to 6 years after vaccination.

METHODS

This phase II, open-label, multicenter, single-group trial conducted in the Czech Republic, Germany, Sweden, and the Netherlands followed 129 subjects who had received two doses (2 months apart) of HZ/su during the initial trial. Vaccine-induced immune responses (frequencies of gE-specific CD4(+) T cells expressing ≥2 activation markers and serum anti-gE antibody concentrations) were evaluated at 48, 60, and 72 months after the first HZ/su dose.

RESULTS

Six years after vaccination with HZ/su, gE-specific cell-mediated immune responses and anti-gE antibody concentrations had decreased by 20-25% from month 36, but remained higher than the prevaccination values. At month 72, the gE-specific cell-mediated immune response was 3.8 times higher than the prevaccination value (477.3 vs. 119.4 activated gE-specific CD4(+) T cells per 10(6) cells), and the anti-gE antibody concentration was 7.3 times higher than the prevaccination value (8159.0 vs. 1121.3mIU/mL). No vaccine-related serious adverse events were reported between months 36 and 72.

CONCLUSIONS

gE-specific cellular and humoral immune responses persisted for 6 years after two-dose vaccination with HZ/su in healthy older adults. No safety concerns were identified.

Risk of herpes zoster in children with asthma

BACKGROUND

There is literature that indicates the association of asthma with an increased risk of common and serious microbial infections. We recently reported an increased risk of vaccine-preventable diseases, e.g., herpes zoster (HZ) among children with asthma, defined by predetermined asthma criteria. Little is known about whether this association is persistent if the asthma status is defined by different asthma criteria, e.g., the Asthma Predictive Index, given the heterogeneity of asthma.

OBJECTIVE

To assess the consistency of the association between asthma and the risk of HZ in children.

METHODS

This is a population-based case-control study based on all pediatric patients with HZ between 1996 and 2001 in Olmsted County, Minnesota, and 1:1 age- and sex-matched controls without a history of HZ who were enrolled in our previous study. The original Asthma Predictive Index criteria was operationalized by two or more wheezing episodes in a year for the first 3 years of life plus one of the major (physician-diagnosed asthma for a parent or physician-diagnosed eczema for a patient) or two of the minor criteria (physician-diagnosed allergic rhinitis for a patient, wheezing apart from cold, or eosinophilia [≥4%]). Data were fit to traditional logistic regression models to calculate odds ratios and 95% confident intervals.

RESULTS

Of the original cohort (n = 554), 95 (17%) did not meet the enrollment criteria for this study, which left 459. Of the 221 patients, 53% were female, with a mean (standard deviation) age of 9.7 ± 4.2 years. The risk of HZ was increased in children with asthma defined by the API controlling for a varicella vaccine history and atopic status (adjusted odds ratio 2.56 [95% confidence interval, 1.08-6.56]).

CONCLUSIONS

The association between asthma and increased risk of HZ in children and adolescents is consistent, independent of asthma definitions. Asthma might be an important clinical condition to be considered in HZ vaccine studies.

Efficacy of an adjuvanted herpes zoster subunit vaccine in older adults

BACKGROUND

In previous phase 1-2 clinical trials involving older adults, a subunit vaccine containing varicella-zoster virus glycoprotein E and the AS01B adjuvant system (called HZ/su) had a clinically acceptable safety profile and elicited a robust immune response.

METHODS

We conducted a randomized, placebo-controlled, phase 3 study in 18 countries to evaluate the efficacy and safety of HZ/su in older adults (≥50 years of age), stratified according to age group (50 to 59, 60 to 69, and ≥70 years). Participants received two intramuscular doses of the vaccine or placebo 2 months apart. The primary objective was to assess the efficacy of the vaccine, as compared with placebo, in reducing the risk of herpes zoster in older adults.

RESULTS

A total of 15,411 participants who could be evaluated received either the vaccine (7698 participants) or placebo (7713 participants). During a mean follow-up of 3.2 years, herpes zoster was confirmed in 6 participants in the vaccine group and in 210 participants in the placebo group (incidence rate, 0.3 vs. 9.1 per 1000 person-years) in the modified vaccinated cohort. Overall vaccine efficacy against herpes zoster was 97.2% (95% confidence interval [CI], 93.7 to 99.0; P<0.001). Vaccine efficacy was between 96.6% and 97.9% for all age groups. Solicited reports of injection-site and systemic reactions within 7 days after vaccination were more frequent in the vaccine group. There were solicited or unsolicited reports of grade 3 symptoms in 17.0% of vaccine recipients and 3.2% of placebo recipients. The proportions of participants who had serious adverse events or potential immune-mediated diseases or who died were similar in the two groups.

CONCLUSIONS

The HZ/su vaccine significantly reduced the risk of herpes zoster in adults who were 50 years of age or older. Vaccine efficacy in adults who were 70 years of age or older was similar to that in the other two age groups. (Funded by GlaxoSmithKline Biologicals; ZOE-50 ClinicalTrials.gov number, NCT01165177.).

Varicella zoster immune status in children treated for acute leukemia

Children treated for acute leukemia are at increased risk of severe infection with varicella zoster virus (VZV). We studied the VZV sero-status of children with acute leukemia prior to starting chemotherapy and after completion of chemotherapy. VZV sero-status was assessed using time resolved fluorescence immunoassay (TRFIA) before starting treatment and 6 months after completion of treatment. Prior to starting treatment for acute leukemia, a significant proportion of children (35%) are VZV seronegative. On completion of treatment most patients maintained protective VZV antibody levels; however, 35% had reduced/loss VZV antibody to a level considered non-protective and susceptible to VZV infection.

Vaccine responsiveness in the elderly: best practice for the clinic

The success of vaccines developed since the beginning of the 20th century, has enabled the conquest of several childhood diseases preventing death and or disability for millions of children. But, globally, the number of children will soon be surpassed by the number of adults over the age of 65. The active lifestyle of these older individuals, coupled with a degree of immune deficiency recognised within this population will lead to a change in the profile of diseases affecting the elderly. The challenge for policy makers and also those involved in primary healthcare is how to protect this population from communicable diseases and keep them healthy, autonomous and independent when vaccines in the main have been developed for use on children and young adults.

Broadly reactive human CD8 T cells that recognize an epitope conserved between VZV, HSV and EBV

Human herpesviruses are important causes of potentially severe chronic infections for which T cells are believed to be necessary for control. In order to examine the role of virus-specific CD8 T cells against Varicella Zoster Virus (VZV), we generated a comprehensive panel of potential epitopes predicted in silico and screened for T cell responses in healthy VZV seropositive donors. We identified a dominant HLA-A*0201-restricted epitope in the VZV ribonucleotide reductase subunit 2 and used a tetramer to analyze the phenotype and function of epitope-specific CD8 T cells. Interestingly, CD8 T cells responding to this VZV epitope also recognized homologous epitopes, not only in the other α-herpesviruses, HSV-1 and HSV-2, but also the γ-herpesvirus, EBV. Responses against these epitopes did not depend on previous infection with the originating virus, thus indicating the cross-reactive nature of this T cell population. Between individuals, the cells demonstrated marked phenotypic heterogeneity. This was associated with differences in functional capacity related to increased inhibitory receptor expression (including PD-1) along with decreased expression of co-stimulatory molecules that potentially reflected their stimulation history. Vaccination with the live attenuated Zostavax vaccine did not efficiently stimulate a proliferative response in this epitope-specific population. Thus, we identified a human CD8 T cell epitope that is conserved in four clinically important herpesviruses but that was poorly boosted by the current adult VZV vaccine. We discuss the concept of a “pan-herpesvirus” vaccine that this discovery raises and the hurdles that may need to be overcome in order to achieve this.

Human herpesviruses can cause a wide range of serious infections. They are extremely common and individuals remain latently infected lifelong, with reactivations often causing recurrent or severe disease. T-cells are important in controlling herpesvirus infections and preventing their reactivation, so vaccines that induce T-cells are likely to improve control. Here, we examined human T-cells against VZV that might allow focused vaccine development. We identified a dominant target against which the majority of subjects had mounted a CD8 T-cell response. We found that very similar targets also exist in three other important herpesviruses, HSV-1, HSV-2 and EBV. We showed that CD8 T-cells recognizing the VZV target could also recognize the others and we hypothesized that recurrent encounter with these viruses could boost this common response. In some individuals, immunization with a VZV vaccine did cause activation of these cells, but in most it did not. This reflects the variable efficacy of the currently available VZV vaccine. Our findings suggest that T-cell targets may be shared between herpesvirus species and may therefore contribute to a novel “pan-herpesvirus” vaccine. However, current VZV vaccines cannot reliably stimulate these T-cells and new strategies will be necessary to achieve this goal.

Cost-effectiveness of vaccination against herpes zoster

Herpes zoster (HZ) is a common disease among elderly, which may develop into a severe pain syndrome labeled postherpetic neuralgia (PHN). A live-attenuated varicella zoster virus vaccine has been shown to be effective in reducing the incidence and burden of illness of HZ and PHN, providing the opportunity to prevent significant health-related and financial consequences of HZ. In this review, we summarize the available literature on cost-effectiveness of HZ vaccination and discuss critical parameters for cost-effectiveness results. A search in PubMed and EMBASE was performed to identify full cost-effectiveness studies published before April 2013. Fourteen cost-effectiveness studies were included, all performed in western countries. All studies evaluated cost-effectiveness among elderly above 50 years and used costs per quality-adjusted life year (QALY) gained as primary outcome. The vast majority of studies showed vaccination of 60- to 75-year-old individuals to be cost-effective, when duration of vaccine efficacy was longer than 10 years. Duration of vaccine efficacy, vaccine price, HZ incidence, HZ incidence and discount rates were influential to the incremental cost-effectiveness ratio (ICER). HZ vaccination may be a worthwhile intervention from a cost-effectiveness point of view. More extensive reporting on methodology and more detailed results of sensitivity analyses would be desirable to address uncertainty and to guarantee optimal comparability between studies, for example regarding model structure, discounting, vaccine characteristics and loss of quality of life due to HZ and PHN.