Efficacy of an adjuvanted herpes zoster subunit vaccine in older adults

Economic Evaluation of Vaccination Programmes in Older Adults and the Elderly: Important Issues and Challenges

High-income countries are undergoing demographic transitions towards populations with substantial larger proportions of older adults. Due to the increased susceptibility of older adults to infectious diseases and their consequences, vaccination programmes are an important health intervention to help maintain healthy ageing. While much of the existing literature suggests that current vaccination programmes targeted at older adults and the elderly are likely to be cost effective in high-income countries, we argue that it is important to more fully consider some important issues and challenges. Since the majority of vaccines have been developed for children, economic evaluations of vaccination programmes have consequentially tended to focus on this age group and on how to incorporate herd-immunity effects. While programmes targeted at older adults and the elderly may also induce some herd effects, there are other important challenges to consider in these economic evaluations. For example, age and time effects in relation to vaccine efficacy and duration of immunity, as well as heterogeneity between targeted individuals in terms of risk of infection, severity of disease and response to vaccination. For some pathogens, there is also the potential for interactions with childhood programmes in the form of herd-immunity effects.

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.

Understanding natural herpes simplex virus immunity to inform next-generation vaccine design

Incremental advances in our knowledge of how natural immune control of herpes simplex virus (HSV) develops have yielded insight as to why previous vaccine attempts have only been partially successful, however, our understanding of these pathways, particularly in humans, is still incomplete. Further elucidation of the innate immune events that are responsible for stimulating these effector responses is required to accurately inform vaccine design. An enhanced understanding of the mechanism of action of novel adjuvants will also facilitate the rational choice of adjuvant to optimise such responses. Here we review the reasons for the hitherto partial HSV vaccine success and align these with our current knowledge of how natural HSV immunity develops. In particular, we focus on the innate immune response and the role of dendritic cells in inducing protective T-cell responses and how these pathways might be recapitulated in a vaccine setting.

Potent response of QS-21 as a vaccine adjuvant in the skin when delivered with the Nanopatch, resulted in adjuvant dose sparing

Adjuvants play a key role in boosting immunogenicity of vaccines, particularly for subunit protein vaccines. In this study we investigated the induction of antibody response against trivalent influenza subunit protein antigen and a saponin adjuvant, QS-21. Clinical trials of QS-21 have demonstrated the safety but, also a need of high dose for optimal immunity, which could possibly reduce patient acceptability. Here, we proposed the use of a skin delivery technology - the Nanopatch - to reduce both adjuvant and antigen dose but also retain its immune stimulating effects when compared to the conventional needle and syringe intramuscular (IM) delivery. We have demonstrated that Nanopatch delivery to skin requires only 1/100(th) of the IM antigen dose to induce equivalent humoral response. QS-21 enhanced humoral response in both skin and muscle route. Additionally, Nanopatch has demonstrated 30-fold adjuvant QS-21 dose sparing while retaining immune stimulating effects compared to IM. QS-21 induced localised, controlled cell death in the skin, suggesting that the danger signals released from dead cells contributed to the enhanced immunogenicity. Taken together, these findings demonstrated the suitability of reduced dose of QS-21 and the antigen using the Nanopatch to enhance humoral responses, and the potential to increase patient acceptability of QS-21 adjuvant.

Issues in the Treatment of Neurological Conditions Caused by Reactivation of Varicella Zoster Virus (VZV)

Varicella zoster virus (VZV) is a ubiquitous neurotropic human herpesvirus. Primary infection usually causes varicella (chicken pox), after which virus becomes latent in ganglia along the entire neuraxis. Decades later, virus reactivates to produce herpes zoster (shingles), a painful dermatomally distributed vesicular eruption. Zoster may be further complicated by postherpetic neuralgia, VZV vasculopathy, myelitis, and segmental motor weakness. VZV reactivation has also been associated with giant cell arteritis. This overview discusses treatment of various conditions that often require both corticosteroids and antiviral drugs. Treatment for VZV-associated disease is often based on case reports and small studies rather than large-scale clinical trials. Issues that require resolution include the optimal duration of such combined therapy, more effective treatment for postherpetic neuralgia, whether some treatments should be given orally or intravenously, the widening spectrum of zoster sine herpete, and the role of antiviral therapy in giant cell arteritis.

Increased risk of herpes zoster in children with cancer: A nationwide population-based cohort study

Herpes zoster is rare in healthy children, but immunocompromised persons have an increased risk of herpes zoster and severe diseases. Considering the very limited information on herpes zoster in children with cancer, we performed a nationwide population-based cohort study to estimate the incidence of herpes zoster in children with cancer and to explore the association between the 2 diseases.Data were obtained from the National Health Research Institutes Database in Taiwan. A total of 4432 children with newly diagnosed cancer between 2000 and 2007 were identified as the cancer cohort, and 17,653 children without cancer frequency-matched by sex and age at entry were considered the noncancer cohort. The association between herpes zoster and childhood cancer was determined.Children with cancer had a higher risk of herpes zoster. The incidence rate of herpes zoster was higher in the cancer cohort than in the noncancer cohort (20.7 vs 2.4 per 10,000 person-years; IRR = 8.6; 95% CI = 4.8-15.6). The cumulative incidence was significantly higher in the cancer cohort (P < 0.0001). Leukemia, lymphoma, and solid tumor were all associated with the increased risk, and leukemia had the highest magnitude of strength of association.This nationwide population-based cohort study demonstrated that children with cancer were associated with an increased risk of herpes zoster. In addition to early antiviral treatment, vaccination with heat-treated zoster vaccine or adjuvanted subunit vaccine could be an appropriate policy to decrease the incidence in children with cancer.

The role of MyD88- and TRIF-dependent signaling in monophosphoryl lipid A-induced expansion and recruitment of innate immunocytes

Treatment with the TLR4 agonist MPLA augments innate resistance to common bacterial pathogens. However, the cellular and molecular mechanisms by which MPLA augments innate immunocyte functions are not well characterized. This study examined the importance of MyD88- and TRIF-dependent signaling for leukocyte mobilization, recruitment, and activation following administration of MPLA. MPLA potently induced MyD88- and TRIF-dependent signaling. A single injection of MPLA caused rapid mobilization and recruitment of neutrophils, a response that was largely mediated by the chemokines CXCL1 and -2 and the hemopoietic factor G-CSF. Rapid neutrophil recruitment and chemokine production were regulated by both pathways although the MyD88-dependent pathway showed some predominance. In further studies, multiple injections of MPLA potently induced mobilization and recruitment of neutrophils and monocytes. Neutrophil recruitment after multiple injections of MPLA was reliant on MyD88-dependent signaling, but effective monocyte recruitment required activation of both pathways. MPLA treatment induced expansion of myeloid progenitors in bone marrow and upregulation of CD11b and shedding of L-selectin by neutrophils, all of which were attenuated in MyD88- and TRIF-deficient mice. These results show that MPLA-induced neutrophil and monocyte recruitment, expansion of bone marrow progenitors and augmentation of neutrophil adhesion molecule expression are regulated by both the MyD88- and TRIF-dependent pathways.

Geriatrics: Year in review

The purpose of this review is to provide an update on topics in general geriatrics that are of interest to the field of geriatric oncology. Based on a review of high-impact journals in geriatrics for the prior two years and reviews of journals in which geriatrics updates are published, updates for hypertension, dementia, vaccination, and frailty are presented here. Recent studies have supported lower, more aggressive blood pressure targets in the management of hypertension, even in older patients. However, controversy remains as to the cognitive and functional effects of aggressive blood pressure targets. Advances in dementia management have been slow, but recent reviews have supported the use of specific screening tools and advocated more widespread screening for mild cognitive impairment and dementia by primary care practitioners. Pharmacologic trials have largely been negative, but a recent multi-component lifestyle intervention showed promise. Significant changes in immunization recommendations have occurred due to two recent large randomized studies of pneumococcal vaccine and a new subunit zoster vaccine. Finally, interventions for frailty syndrome in the geriatric population have been somewhat variable, with some promise in addressing exercise, nutrition, as well as pharmacologic treatment of frailty.

Quantification of risk factors for postherpetic neuralgia in herpes zoster patients: A cohort study

OBJECTIVE

To investigate risk factors for postherpetic neuralgia, the neuropathic pain that commonly follows herpes zoster.

METHODS

Using primary care data from the Clinical Practice Research Datalink, we fitted multivariable logistic regression models to investigate potential risk factors for postherpetic neuralgia (defined as pain ≥90 days after zoster, based on diagnostic or prescription codes), including demographic characteristics, comorbidities, and characteristics of the acute zoster episode. We also assessed whether the effects were modified by antiviral use.

RESULTS

Of 119,413 zoster patients, 6,956 (5.8%) developed postherpetic neuralgia. Postherpetic neuralgia risk rose steeply with age, most sharply between 50 and 79 years (adjusted odds ratio [OR] for a 10-year increase, 1.70, 99% confidence interval 1.63-1.78). Postherpetic neuralgia risk was higher in women (6.3% vs 5.1% in men: OR 1.19, 1.10-1.27) and those with severely immunosuppressive conditions, including leukemia (13.7%: 2.07, 1.08-3.96) and lymphoma (12.7%: 2.45, 1.53-3.92); autoimmune conditions, including rheumatoid arthritis (9.1%: 1.20, 0.99-1.46); and other comorbidities, including asthma and diabetes. Current and ex-smokers, as well as underweight and obese individuals, were at increased risk of postherpetic neuralgia. Antiviral use was not associated with postherpetic neuralgia (OR 1.04, 0.97-1.11). However, the increased risk associated with severe immunosuppression appeared less pronounced in patients given antivirals.

CONCLUSIONS

Postherpetic neuralgia risk was increased for a number of patient characteristics and comorbidities, notably with age and among those with severe immunosuppression. As zoster vaccination is contraindicated for patients with severe immunosuppression, strategies to prevent zoster in these patients, which could include the new subunit zoster vaccine, are an increasing priority.

Varicella-zoster virus susceptibility and primary healthcare consultations in Norway

BACKGROUND

Currently Norway does not recommend universal varicella vaccination for healthy children. This study assessed susceptibility to varicella-zoster virus (VZV) in the Norwegian population for the first time.

METHODS

A national convenience sample of residual sera was tested for anti-VZV IgG by ELISA. We estimated age-specific seropositivity to VZV, controlling for sex and geographical distribution. We assessed differences between the proportions using the chi-square test and multivariable logistic regression. Seroprevalence data were compared to the varicella and herpes zoster-associated consultation rates in patients attending primary healthcare.

RESULTS

Although 73.2 % (n = 1,540) of all samples were positive for VZV, only 11.2 % of samples collected from 1-year-olds were seropositive. There was a sharp increase in the proportion of seropositive in 3- and 5-year-olds (40.2 % and 65.4 %, respectively). By the school entry age of 6 years, 69.8 % of children were seropositive. The age-specific annual consultation rate for varicella in primary healthcare peaked in 1-year-olds, with 2,627 cases per 100,000 population. The profile of varicella-related consultations in primary healthcare mirrored the VZV seropositivity profile. The herpes zoster-related consultations in primary healthcare peaked in people over 70 years of age (702 cases per 100,000 population).

CONCLUSIONS

VZV seroprevalence in Norway was somewhat lower than in some other European countries. The age-specific varicella-related consultation rates in primary healthcare mirrored the age profile of VZV seroprevalence.

Travel vaccination recommendations and endemic infection risks in solid organ transplantation recipients

BACKGROUND

Solid organ transplant (SOT) recipients are often heavily immunosuppressed and consequently at risk of serious illness from vaccine preventable viral and bacterial infections or with endemic fungal and parasitic infections. We review the literature to provide guidance regarding the timing and appropriateness of vaccination and pathogen avoidance related to the immunological status of SOT recipients.

METHODS

A PUBMED search ([Vaccination OR vaccine] AND/OR ["specific vaccine"] AND/OR [immunology OR immune response OR cytokine OR T lymphocyte] AND transplant was performed. A review of the literature was performed in order to develop recommendations on vaccination for SOT recipients travelling to high-risk destinations.

RESULTS

Whilst immunological failure of vaccination in SOT is primarily the result of impaired B-cell responses, the role of T-cells in vaccine failure and success remains unknown. Vaccination should be initiated at least 4 weeks prior to SOT or more than 6 months post-SOT. Avoidance of live vaccination is generally recommended, although some live vaccines may be considered in the specific situations (e.g. yellow fever). The practicing physician requires a detailed understanding of region-specific endemic pathogen risks.

CONCLUSIONS

We provide a vaccination and endemic pathogen guide for physicians and travel clinics involved in the care of SOT recipients. In addition, recommendations based on timing of anticipated immunological recovery and available evidence regarding vaccine immunogenicity in SOT recipients are provided to help guide pre-travel consultations.

Impact of adjuvants on CD4(+) T cell and B cell responses to a protein antigen vaccine: Results from a phase II, randomized, multicenter trial

Immunogenicity and safety of different adjuvants combined with a model antigen (HBsAg) were compared. Healthy HBV-naïve adults were randomized to receive HBs adjuvanted with alum or Adjuvant Systems AS01B, AS01E, AS03A or AS04 at Days 0 and 30. Different frequencies of HBs-specific CD4+ T cells 14days post dose 2 but similar polyfunctionality profiles were induced by the different adjuvants with frequencies significantly higher in the AS01B and AS01E groups than in the other groups. Antibody concentrations 30days post-dose 2 were significantly higher in AS01B, AS01E and AS03A than in other groups. Limited correlations were observed between HBs-specific CD4+ T cell and antibody responses. Injection site pain was the most common solicited local symptom and was more frequent in AS groups than in alum group. Different adjuvants formulated with the same antigen induced different adaptive immune responses and reactogenicity patterns in healthy naïve adults. The results summary for this study (GSK study number 112115 - NCT# NCT00805389) is available on the GSK Clinical Study Register and can be accessed at www.gsk-clinicalstudyregister.com.

Incidence and risk factors of herpes zoster in human immunodeficiency virus-positive patients initiating combination antiretroviral therapy in Taiwan

BACKGROUND/PURPOSE

To obtain current epidemiological data for better vaccination policies, this study aimed to assess the incidence and risk factors of herpes zoster in human immunodeficiency virus (HIV)-positive patients initiating combination antiretroviral therapy (cART) in Taiwan.

METHODS

Between June, 2012 and May, 2015, we prospectively identified zoster cases in HIV-positive patients initiating cART. Clinical information was collected on demographics, prior zoster, plasma HIV-1 RNA load (PVL), and CD4 count at baseline and during follow up. A case-control study by 1:2 matched pairs was used to identify the risk factors for zoster development.

RESULTS

During the 3-year study period, 826 patients with a mean age of 32.9 years were included, and 7.7% had prior zoster. The mean baseline CD4 count and PVL were 286 cells/μL and 4.90 log₁₀ copies/mL, respectively. Fifty-four (6.5%) patients developed zoster after initiation of cART, with 43 episodes (79.6%) occurring within 1 year of cART initiation, which corresponded to an overall incidence rate of 3.61/100 person-years. The multivariate analysis revealed that prior zoster (adjusted odds ratio = 3.143; 95% confidence interval, 1.385-7.133) and baseline CD4 count < 200 cells/μL (adjusted odds ratio = 2.034; 95% confidence interval, 1.020-4.057) were independent risk factors for zoster in HIV-positive patients initiating cART. In case-control study, prior zoster and baseline PVL > 5 log₁₀ copies/mL were risk factors for zoster development after cART initiation in multivariate analysis.

CONCLUSIONS

Herpes zoster occurred in 6.5% of HIV-positive Taiwanese patients after initiation of cART, which was associated with prior zoster and baseline CD4 count < 200 cells/μL or baseline PVL > 5 log₁₀ copies/mL.

Fatal disseminated varicella zoster infection following zoster vaccination in an immunocompromised patient

A 79-year-old man with chronic lymphocytic leukaemia presented with fever and a widespread vesicular rash on 19 November 2014. The patient had not been under immunosuppressive regime for 6 months. He had received a shingles vaccine on 14th October and developed flu-like symptoms after 2 weeks. Intravenous antimicrobial therapy including aciclovir was started. He remained stable with no evidence of systemic involvement. On day 5, he developed respiratory and renal failure that required transfer to intensive care unit. Vesicle fluid, bronchoalveolar lavage and plasma were positive for varicella zoster virus by PCR. Slight clinical improvement allowed extubation on day 16. He subsequently deteriorated and died on day 25. Multiorgan failure was considered the immediate cause of death whereas disseminated varicella zoster infection was stated in the medical certificate as the other condition leading to this outcome. Varicella zoster Oka vaccine strain was detected in vesicle fluid, using PCR.

Varicella Zoster Virus: A Common Cause of Stroke in Children and Adults

BACKGROUND

Varicella zoster virus (VZV) is a neurotropic, exclusively human herpesvirus. Primary infection causes varicella (chickenpox), after which the virus becomes latent in ganglionic neurons along the entire neuraxis. As cell-mediated immunity to VZV declines with advancing age and immunosuppression, VZV reactivates to produce zoster (shingles). One of the most serious complications of zoster is VZV vasculopathy.

METHODS

We reviewed recent studies of stroke associated with varicella and zoster, how VZV vasculopathy is verified virologically, vaccination to prevent varicella and immunization to prevent zoster, and VZV in giant cell arteritis (GCA).

FINDINGS

We report recent epidemiological studies revealing an increased risk of stroke after zoster; the clinical, laboratory, and imaging features of VZV vasculopathy; that VZV vasculopathy is confirmed by the presence of either VZV DNA or anti-VZV IgG antibody in cerebrospinal fluid; special features of VZV vasculopathy in children; vaccination to prevent varicella and immunization to prevent zoster; and the latest evidence linking VZV to GCA.

CONCLUSION

In children and adults, VZV is a common cause of stroke.

Local innate immune responses in the vaccine adjuvant-injected muscle

Inducing a high magnitude of antibodies, possibly in combination with T-cell responses that offer epitope breadth over prolonged periods of time is likely a prerequisite for effective vaccines against severe diseases such as HIV-1 infection, malaria and tuberculosis. A much better understanding of the innate immune mechanisms that are critical for inducing desired responses to vaccination would help in the design of novel vaccines. The majority of human vaccines are administered into the muscle. In this brief review, we focus on the initial innate immune events that occur locally at the site of intramuscular vaccine delivery, and how they are influenced by clinically approved vaccine adjuvants. In particular, the effects on cell mobilization, cell activation and vaccine antigen uptake are reviewed. Understanding how distinct adjuvants enhance and tailor vaccine responses would facilitate the selection of the best-suited adjuvant to improve vaccine efficacy to a given pathogen.

Vaccination with the Secreted Glycoprotein G of Herpes Simplex Virus 2 Induces Protective Immunity after Genital Infection

Herpes simplex virus 2 (HSV-2) infects the genital mucosa and establishes a life-long infection in sensory ganglia. After primary infection HSV-2 may reactivate causing recurrent genital ulcerations. HSV-2 infection is prevalent, and globally more than 400 million individuals are infected. As clinical trials have failed to show protection against HSV-2 infection, new vaccine candidates are warranted. The secreted glycoprotein G (sgG-2) of HSV-2 was evaluated as a prophylactic vaccine in mice using two different immunization and adjuvant protocols. The protocol with three intramuscular immunizations combining sgG-2 with cytosine-phosphate-guanine dinucleotide (CpG) motifs and alum induced almost complete protection from genital and systemic disease after intra-vaginal challenge with HSV-2. Robust immunoglobulin G (IgG) antibody titers were detected with no neutralization activity. Purified splenic CD4+ T cells proliferated and produced interferon-γ (IFN-γ) when re-stimulated with the antigen in vitro. sgG-2 + adjuvant intra-muscularly immunized mice showed a significant reduction of infectious HSV-2 and increased IFN-γ levels in vaginal washes. The HSV-2 DNA copy numbers were significantly reduced in dorsal root ganglia, spinal cord, and in serum at day six or day 21 post challenge. We show that a sgG-2 based vaccine is highly effective and can be considered as a novel candidate in the development of a prophylactic vaccine against HSV-2 infection.

Herpes Zoster

Herpes zoster causes significant suffering owing to acute and chronic pain or postherpetic neuralgia (PHN). Varicella-zoster virus-induced neuronal destruction and inflammation causes the principal problems of pain, interference with activities of daily living, and reduced quality of life in older adults. The optimal treatment of herpes zoster requires early antiviral therapy and careful pain management. For patients who have PHN, evidence-based pharmacotherapy using topical lidocaine patch, gabapentin, pregabalin, tricyclic antidepressants, or opiates can reduce pain burden. The live attenuated zoster vaccine is effective in reducing pain burden and preventing herpes zoster and PHN in older adults.

Immune response and reactogenicity of intradermal administration versus subcutaneous administration of varicella-zoster virus vaccine: an exploratory, randomised, partly blinded trial

BACKGROUND

The licensed live, attenuated varicella-zoster virus vaccine prevents herpes zoster in adults older than 50 years. We aimed to determine whether intradermal administration of zoster vaccine could enhance vaccine immunogenicity compared with conventional needle subcutaneous administration.

METHODS

In this randomised, dose-ranging study, adults aged 50 years or older who had a history of varicella or who had resided in a country with endemic varicella-zoster virus infection for 30 years or more were eligible. Participants received the approved full or a 1/3 dose of zoster vaccine given subcutaneously or one of four intradermal doses (full, 1/3, 1/10, or 1/27 dose) using the MicronJet600 device. The two subcutaneous doses and the four intradermal doses were randomised (1·5:1:1:1:1:1) by computer generated sequence with randomisation stratified by age (50-59 years or 60 years or older). The primary immunogenicity endpoint was the change from baseline in IgG antibody to varicella-zoster virus-specific glycoproteins (gpELISA) measured at 6 weeks. All patients were included in the primary and safety analyses. This study is registered with ClinicalTrials.gov, number NCT01385566.

FINDINGS

Between Sept 2, 2011, and Jan 13, 2012, 224 participants were enrolled from three clinics in the USA and 223 were randomly assigned: 52 to receive the full dose subcutaneous zoster vaccine, 34 to receive the 1/3 dose subcutaneous zoster vaccine, 34 to receive the full dose intradermal zoster vaccine, 35 to receive the 1/3 dose intradermal zoster vaccine, 34 to receive the 1/10 dose intradermal zoster vaccine, and 34 to receive the 1/27 dose intradermal zoster vaccine. Full dose zoster vaccine given subcutaneously resulted in a gpELISA geometric mean fold-rise (GMFR) of 1·74 (90% CI 1·48-2·04) at 6 weeks post-vaccination compared with intradermal administration which resulted in a significantly higher gpELISA GMFR of 3·25 (2·68-3·94; p<0·0001), which also remained high at 18 months. An apparent dose-response relation was observed with intradermal administration (1/3 dose subcutaneous GMFR 1·64 [90% CI 1·36-1·99], 1/3 dose intradermal 2·58 (2·13-3·13), 1/10 dose intradermal 2·22 [1·83-2·69], and 1/27 dose intradermal 1·64 [1·35-2·00]). Each partial dose of zoster vaccine given intradermaly had a gpELISA GMFR comparable to that of full dose zoster vaccine given subcutaneously. Transient erythema and induration were more common after intradermal administration (31% erythema for full subcutaneous dose and 77% for intradermal dose).

INTERPRETATION

Intradermal zoster vaccine showed a greater increase in varicella-zoster virus gpELISA antibody compared with subcutaneous zoster vaccine at comparable doses. Larger and longer studies of intradermal administration of live, attenuated zoster vaccine are needed to provide convincing evidence of improved cell mediated immunity.

FUNDING

Merck & Co Inc.

Cost of Herpes Zoster in Patients With Selected Immune-Compromised Conditions in the United States

Among patients with common immune-compromised (IC) conditions in the United States, the healthcare cost associated with herpes zoster (HZ) was sizable and occurred mainly during the first quarter after diagnosis. And HZ-associated costs varied by age and underlying IC conditions.

Background. This retrospective study investigates the healthcare costs of herpes zoster (HZ) in patients with selected immune-compromised (IC) conditions in the United States (US).

Methods. Patients with incident HZ diagnosis (index date) were selected from nationwide administrative claims databases from 2005 to 2009. Baseline IC groups, analyzed separately, included adults aged 18–64 years with the following: human immunodeficiency virus infection (HIV), solid organ transplant (SOT), bone marrow or stem cell transplant (BMSCT), or cancer; and older adults (aged ≥65 years) with cancer. Herpes zoster patients (n = 2020, n = 1053, n = 286, n = 13 178, and n = 9089, respectively) were 1-to-1 matched to controls without HZ (with randomly selected index date) in the same baseline group. The healthcare resource utilization and costs (2014 US dollars) during the first 2 postindex quarters were compared between matched cohorts with continuous enrollment during the quarter.

Results. Herpes zoster patients generally had greater use of inpatient, emergency room and outpatient services, and pain medications than matched controls (P < .05). The incremental costs of HZ during the first postindex quarter were $3056, $2649, $13 332, $2549, and $3108 for HIV, SOT, BMSCT, cancer in adults aged 18–64 years, and cancer in older adults, respectively (each P < .05). The incremental costs of HZ during the second quarter were only significant for adults aged 18–64 years with cancer ($1748, P < .05). The national incremental costs of HZ were projected to be $298 million annually across the 5 IC groups.

Conclusions. The healthcare cost associated with HZ among patients with studied IC conditions was sizable and occurred mainly during the first 90 days after diagnosis.

Status of vaccine research and development of vaccines for herpes simplex virus

Herpes simplex virus type-1 (HSV-1) and -2 (HSV-2) are highly prevalent global pathogens which commonly cause recurrent oral and genital ulcerations. Less common but more serious complications include meningitis, encephalitis, neonatal infection, and keratitis. HSV-2 infection is a significant driver of the HIV epidemic, increasing the risk of HIV acquisition 3 fold. As current control strategies for genital HSV-2 infection, including antiviral therapy and condom use, are only partially effective, vaccines will be required to reduce infection. Both preventive and therapeutic vaccines for HSV-2 are being pursued and are in various stages of development. We will provide an overview of efforts to develop HSV-2 vaccines, including a discussion of the clinical need for an HSV vaccine, and status of research and development with an emphasis on recent insights from trials of vaccine candidates in clinical testing. In addition, we will touch upon aspects of HSV vaccine development relevant to low and middle income countries.

Vaccines for preventing herpes zoster in older adults

BACKGROUND

Herpes zoster, also known as 'shingles', is a neurocutaneous disease characterised by the reactivation of the latent varicella zoster virus (VZV), the virus that causes chickenpox when immunity to VZV declines. It is an extremely painful condition that can last many weeks or months and it can significantly compromise the quality of life of affected individuals. The natural process of aging is associated with a reduction in cellular immunity and this predisposes older people to herpes zoster. Vaccination with an attenuated form of VZV activates specific T cell production avoiding viral reactivation. The Food and Drug Administration has approved a herpes zoster vaccine with an attenuated active virus for clinical use among older adults, which has been tested in large populations. A new adjuvanted recombinant VZV subunit zoster vaccine has also been tested. It consists of recombinant VZV glycoprotein E and a liposome-based AS01B adjuvant system. This new vaccine is not yet available for clinical use.

OBJECTIVES

To evaluate the effectiveness and safety of vaccination for preventing herpes zoster in older adults.

SEARCH METHODS

For this 2015 update, we searched the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 9), MEDLINE (1948 to the 3rd week of October 2015), EMBASE (2010 to October 2015), CINAHL (1981 to October 2015) and LILACS (1982 to October 2015).

SELECTION CRITERIA

Randomised controlled trials (RCTs) or quasi-RCTs comparing zoster vaccine with placebo or no vaccine, to prevent herpes zoster in older adults (mean age > 60 years).

DATA COLLECTION AND ANALYSIS

Two review authors independently collected and analysed data using a data extraction form. They also performed 'Risk of bias' assessment.

MAIN RESULTS

We identified 13 studies involving 69,916 participants. The largest study included 38,546 participants. All studies were conducted in high-income countries and included only healthy Caucasian individuals ≥ 60 years of age without immunosuppressive comorbidities. Ten studies used live attenuated varicella zoster virus (VZV) vaccines. Three studies tested a new type of vaccine not yet available for clinical use. We judged five of the included studies to be at low risk of bias.The incidence of herpes zoster, at up to three years of follow-up, was lower in participants who received the vaccine than in those who received a placebo: risk ratio (RR) 0.49; 95% confidence interval (CI) 0.43 to 0.56, risk difference (RD) 2%, number needed to treat to benefit (NNTB) 50; GRADE: moderate quality evidence. The vaccinated group had a higher incidence of mild to moderate intensity adverse events. These date came from one large study that included 38,546 people aged 60 years or older.A study including 8122 participants compared the new vaccine (not yet available) to the placebo; the group that received the new vaccine had a lower incidence of herpes zoster at 3.2 years of follow-up: RR 0.04, 95% CI 0.02 to 0.10, RD 3%, NNTB 33; GRADE: moderate quality evidence. The vaccinated group had a higher incidence of adverse events but most them were of mild to moderate intensity.All studies received funding from the pharmaceutical industry.

AUTHORS' CONCLUSIONS

Herpes zoster vaccine is effective in preventing herpes zoster disease and this protection can last three years. In general, zoster vaccine is well tolerated; it produces few systemic adverse events and injection site adverse events of mild to moderate intensity.There are studies of a new vaccine (with a VZV glycoproteic fraction plus adjuvant), which is currently not yet available for clinical use.

Comparative preclinical evaluation of AS01 versus other Adjuvant Systems in a candidate herpes zoster glycoprotein E subunit vaccine

The candidate vaccine HZ/su is being developed to prevent herpes-zoster disease (HZ). HZ occurrence is attributed to declines in varicella-zoster virus (VZV) specific T-cell immunity. HZ/su contains VZV antigen, gE, and Adjuvant System AS01_B (liposome-based formulation of MPL and QS-21). In clinical trials, AS01_B enhances CD4⁺ T-cell responses to gE. In clinical trials of other vaccines, Adjuvant Systems AS03 and AS04 also enhance antigen-specific CD4⁺ T-cell responses. Hence the purpose of this study was to evaluate gE formulated with AS01_B, AS01_E (50% less MPL and QS-21 than AS01_B), AS03 or AS04 in C57BL6 mice primed with live-attenuated VZV. Four-weeks post-vaccination, the gE-specific CD4⁺ T-cell response to gE/AS01_B was 5.4, 2.8 and 2.2-fold greater than those to gE/AS03, gE/AS04 and gE/AS03, respectively (p<0.001). Therefore in the VZV-primed mouse model, CD4⁺ T-cell responses to gE appeared most enhanced by AS01_B, and adds further support for the use of AS01_B in the HZ/su formulation.

Liposomal adjuvants for human vaccines

INTRODUCTION

Liposomes are well-known as drug carriers, and are now critical components of two of six types of adjuvants present in licensed vaccines. The liposomal vaccine adjuvant field has long been dynamic and innovative, and research in this area is further examined as new commercial products appear in parallel with new vaccines. In an arena where successful products exist the potential for new types of vaccines with liposomal adjuvants, and alternative liposomal adjuvants that could emerge for new types of vaccines, are discussed.

AREAS COVERED

Major areas include: virosomes, constructed from phospholipids and proteins from influenza virus particles; liposomes containing natural and synthetic neutral or anionic phospholipids, cholesterol, natural or synthetic monophosphoryl lipid A, and QS21 saponin; non-phospholipid cationic liposomes; and combinations and mixtures of liposomes and immunostimulating ingredients as adjuvants for experimental vaccines.

EXPERT OPINION

Liposomes containing monophosphoryl lipid A and QS21 have considerable momentum that will result soon in emergence of prophylactic vaccines to malaria and shingles, and possible novel cancer vaccines. The licensed virosome vaccines to influenza and hepatitis A will be replaced with virosome vaccines to other infectious diseases. Alternative liposomal formulations are likely to emerge for difficult diseases such as tuberculosis or HIV-1 infection.

Is herpes zoster an additional complication in old age alongside comorbidity and multiple medications? Results of the post hoc analysis of the 12-month longitudinal prospective observational ARIZONA cohort study

OBJECTIVES

To examine the burden of comorbidity, polypharmacy and herpes zoster (HZ), an infectious disease, and its main complication post-herpetic neuralgia (PHN) in young (50-70 years of age: 70-) and old (≥ 70 years of age: 70+) patients.

DESIGN

Post hoc analysis of the results of the 12-month longitudinal prospective multicentre observational ARIZONA cohort study.

SETTINGS AND PARTICIPANTS

The study took place in primary care in France from 20 November 2006 to 12 September 2008. Overall, 644 general practitioners (GPs) collected data from 1358 patients aged 50 years or more with acute eruptive HZ.

OUTCOME MEASURES

Presence of HZ-related pain or PHN (pain persisting >3 months) was documented at day 0 and at months 3, 6, and 12. To investigate HZ and PHN burden, pain, quality of life (QoL) and mood were self-assessed using validated questionnaires (Zoster Brief Pain Inventory, 12-item Short-Form health survey and Hospital Anxiety and Depression Scale, respectively).

RESULTS

As compared with younger patients, older patients more frequently presented with comorbidities, more frequently took analgesics and had poorer response on all questionnaires, indicating greater burden, at inclusion. Analgesics were more frequently prescribed to relieve acute pain or PHN in 70+ than 70- patients. Despite higher levels of medication prescription, poorer pain relief and poorer response to all questionnaires were reported in 70+ than 70- patients.

CONCLUSIONS

Occurrence of HZ and progression to PHN adds extra burden on top of pharmacological treatment and impaired quality of life, especially in older patients who already have health problems to cope with in everyday life.

A highly conserved epitope-vaccine candidate against varicella-zoster virus induces neutralizing antibodies in mice

Varicella-zoster virus (VZV) is a highly infectious agent of varicella and herpes zoster (HZ). Vaccination is by far the most effective way to prevent these diseases. More safe, stable and efficient vaccines, such as epitope-based vaccines, now have been increasingly investigated by many researchers. However, only a few VZV neutralizing epitopes have been identified to date. We have previously identified a linear epitope between amino acid residues 121 and 135 of gE. In this study, we validated that this epitope is highly conserved amongst different VZV strains that covered five existing phylogenetic clades with an identity of 100%. We evaluated the immunogenicity of the recombinant hepatitis B virus core (HBc) virus-like particles (VLPs) which included amino acids (121-135). VZV-gE-specific antibodies were detected in immunized mouse serum using ELISA. The anti-peptide antiserum positively detected VZV via Western blot and immunofluorescent staining assays. More importantly, these peptides could neutralize VZV, indicating that these peptides represented neutralizing epitopes. These findings have important implications for the development of epitope-based protective VZV vaccines.

Current and future effects of varicella and herpes zoster vaccination in Germany - Insights from a mathematical model in a country with universal varicella vaccination

Varicella zoster virus (VZV) is primarily known for causing varicella in childhood, but can reactivate again as herpes zoster (HZ) after a period of latency, mainly in persons older than 50 years. Universal varicella vaccination was introduced in Germany in 2004, while HZ vaccination has not been recommended yet. We aimed to quantify the potential long-term effects of universal childhood varicella vaccination and HZ vaccination of the elderly on varicella and HZ incidence in Germany over a time horizon of 100 years, using a transmission model calibrated to pre-vaccination data and validated against early post-vaccination data. Using current vaccination coverage rates of 87% (64%) with one (two) varicella vaccine dose(s), the model predicts a decrease in varicella cases by 89% for the year 2015. In the long run, the incidence reduction will stabilize at about 70%. Under the assumption of the boosting hypothesis of improved HZ protection caused by exposure to VZV, the model predicts a temporary increase in HZ incidence of up to 20% for around 50 years. HZ vaccination of the elderly with an assumed coverage of 20% has only limited effects in counteracting this temporary increase in HZ incidence. However, HZ incidence is shown to decrease in the long-term by 58% as vaccinated individuals get older and finally reach age-classes with originally high HZ incidence. Despite substantial uncertainties around several key variables, the model's results provide valuable insights that support decision-making regarding national VZV vaccination strategies.

Extensive CD4 and CD8 T Cell Cross-Reactivity between Alphaherpesviruses

The Alphaherpesvirinae subfamily includes HSV types 1 and 2 and the sequence-divergent pathogen varicella zoster virus (VZV). T cells, controlled by TCR and HLA molecules that tolerate limited epitope amino acid variation, might cross-react between these microbes. We show that memory PBMC expansion with either HSV or VZV enriches for CD4 T cell lines that recognize the other agent at the whole-virus, protein, and peptide levels, consistent with bidirectional cross-reactivity. HSV-specific CD4 T cells recovered from HSV-seronegative persons can be explained, in part, by such VZV cross-reactivity. HSV-1-reactive CD8 T cells also cross-react with VZV-infected cells, full-length VZV proteins, and VZV peptides, as well as kill VZV-infected dermal fibroblasts. Mono- and cross-reactive CD8 T cells use distinct TCRB CDR3 sequences. Cross-reactivity to VZV is reconstituted by cloning and expressing TCRA/TCRB receptors from T cells that are initially isolated using HSV reagents. Overall, we define 13 novel CD4 and CD8 HSV-VZV cross-reactive epitopes and strongly imply additional cross-reactive peptide sets. Viral proteins can harbor both CD4 and CD8 HSV/VZV cross-reactive epitopes. Quantitative estimates of HSV/VZV cross-reactivity for both CD4 and CD8 T cells vary from 10 to 50%. Based on these findings, we hypothesize that host herpesvirus immune history may influence the pathogenesis and clinical outcome of subsequent infections or vaccinations for related pathogens and that cross-reactive epitopes and TCRs may be useful for multi-alphaherpesvirus vaccine design and adoptive cellular therapy.

Adjuvanted herpes zoster subunit vaccine

This review highlights the characteristics of a candidate herpes zoster (HZ) vaccine (HZ/su, GlaxoSmithKline Vaccines) that consists of 50 μg recombinant glycoprotein E (gE) of varicella zoster virus adjuvanted with AS01B. It is well tolerated and shows a clinically acceptable tolerability profile. It strongly enhances pre-existing gE-specific CD4+ T-cell and anti-gE antibody responses in older adults and immunocompromised persons. Administration of two doses 2 months apart reduces the risk of HZ by 97.2% in adults ≥50 years. This effect does not diminish with increasing age. Long-term persistence of its efficacy still needs to be determined. This candidate HZ vaccine may become an alternative for the high-dose live-attenuated varicella zoster virus vaccine for the prevention of HZ in older persons and in immunocompromised patients in whom the use of live-attenuated vaccines is contraindicated.

[Relation between disease modifying anti-rheumatic drugs and herpes zoster in rheumatoid arthritis]

Biologics have revolutionized the treatment of rheumatoid arthritis (RA). However certain amount of the patients cannot achieve goal of therapy. Recently, compounds targeting the intracellular kinase, Janus kinase (JAK) have demonstrated therapeutic effects resembling biologics. Tofacitinib is the only JAK inhibitor approved for RA and during the clinical trial, increased events of herpes zoster (HZ) was observed. Incidence rate was twice as much as patients treated with conventional anti-rheumatic drug and was especially increased in Japan that was four times as much. The risk factors were age and glucocorticoid that is identical to that of common RA patients and there was nothing specific for tofacitinib. Mechanism of increased incidence of HZ and the difference in ethnicity remains unknown. Analysis of clinical trials have identified that HZ do not correlate with further adverse events. Therefore, it is extremely important to accumulate clinical data with considerable amount of patients with long term follow up including the post marketing surveillance in Japan to reveal the significance of increased HZ in RA patients.

Vaccination against Viruses

Most vaccines in use today are the result of empirical development. The mechanism of action of many vaccines in common use remains incompletely understood. Understanding how such vaccines protect is an ongoing subject of study using increasingly sophisticated immunological tools, such as B cell and T cell repertoire and transcriptome analysis. Such tools are also being applied to the design of vaccines against those viral targets that have evaded vaccine-mediated protection thus far. As basic immunological science intersects with the practicalities of assuring vaccine safety, tolerability, efficacy, and consistency in the clinic, the practical utility of more sophisticated immunological measures for vaccine development may be determined by whether they can be reduced to simply executed, highly standardized, reproducible assays with outcomes that have clear interpretations for vaccine development and use. Basic immunology, empirical vaccine testing, and regulatory science are all necessary contributors to developing the next generation of vaccines, including vaccines effective against the pathogens for which vaccines are not currently available.

Efficacy of varicella (VZV) vaccination: an update for the clinician

Varicella-zoster virus (VZV) infection causes two distinct clinical conditions. Primary varicella infection results in chickenpox, a contagious rash illness typically seen among children. VZV can reactivate years after the initial infection to cause herpes zoster (HZ) and lead to post-herpetic neuralgia, a common complication resulting in persistent pain that may last for years after the zoster rash resolves. A person's risk of having longer lasting and more severe pain associated with HZ increases with age. Since the introduction of VZV vaccines, the rates of infection, hospitalizations, and mortality have declined. In this review, we discuss in detail current VZV vaccines available for the prevention of VZV and HZ infections. Varilrix (GSK Biologicals, UK), Varivax (Merck, USA) and the combined measles, mumps, rubella, and varicella (MMRV) vaccine contain the live attenuated Oka strain of VZV for routine varicella vaccination. While Zostavax is the only HZ vaccine currently approved for use in the United States and the European Union [EMEA, 2011], a subunit vaccine candidate called HZ/su has recently shown improved efficacy for zoster prevention in two clinical trial phase III studies. VariZIG, a post-exposure prophylactic, uses zoster immune globulin to prevent VZV infection in those who have recently been in contact with VZV but lack evidence of varicella immunity and are contraindicated to receive the varicella vaccine. Further, we discuss the skin tropic and neurotropic factor VZV ORF7 gene and its involvement in varicella infection, reactivation and latency in ganglia. Ultimately, these studies can contribute to the development of a neuroattenuated vaccine candidate against varicella or a vector for delivery of other virus antigens.

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.

[Vaccines against Herpes zoster: Effectiveness, safety, and cost/benefit ratio]

CONTEXT

A vaccination against herpes zoster and its complication is available in France since June 2015. Its exact benefit for public health is still controversial and its level of protection is not optimal. All those reasons seem to suggest a low acceptation rate from general practitioners.

OBJECTIVE

To evaluate the effectiveness, the safety, and the cost/benefit ratio of the vaccination against herpes zoster in people aged 50 year or over.

DOCUMENTARY SOURCE

Systematic review in Medline and PubMed with research by key words: "herpes zoster vaccine", "zoster vaccine" and "post herpetic neuralgia vaccine".

SELECTION OF STUDIES

Randomized and observational studies published in English and French language have been selected by two readers.

RESULTS

On 1886 articles identified, 62 studies were included in this systematic review of which 21 randomized trials, 21 observational studies, and 17 medico-economic studies concerned the unadjuvanted vaccine. Considered studies showed an effectiveness of 50% against herpes zoster and 60% on post-herpetic neuralgia incidence of the unadjuvanted vaccine. Five randomized controlled studies were identified for the adjuvanted vaccine. The overall effectiveness of this vaccine was > 90% whatever the age of subjects including those over age 70 and 80. The medico-economic studies conducted in many countries have shown that vaccine policies were beneficial in individuals aged 60 years or over.

LIMITATION OF THE WORK

Most of data of effectiveness, and tolerance result from 2 large controlled studies only (SPS and ZEST) for the unadjuvanted vaccine and only one for the adjuvanted vaccine.

CONCLUSION

Despite controversy and few uncertainties, the vaccine significantly reduces herpes zoster and its complication incidence. In terms of public health objectives, it reduces the burden of the disease and has a positive medico-economic impact. Preliminary data concerning the adjuvanted vaccine, whilst very promising, are still too limited. Up to now, no group of people with particularly high risk of herpes zoster-related complication who will beneficiate the most of the vaccination has been identified yet and only an age criteria has been considered for the recommendation.

Meeting the Challenges of Immunizing Adults

The overall burden of illness from diseases for which vaccines are available disproportionately falls on adults. Adults are recommended to receive vaccinations based on their age, underlying medical conditions, lifestyle, prior vaccinations, and other considerations. Updated vaccine recommendations from CDC are published annually in the U.S. Adult Immunization Schedule. Vaccine use among U.S. adults is low. Although receipt of a provider (physician or other vaccinating healthcare provider) recommendation is a key predictor of vaccination, more often consumers report not receiving vaccine recommendations at healthcare provider visits. Although providers support the benefits of vaccination, they also report several barriers to vaccinating adults, including the cost of providing vaccination services, inadequate or inconsistent payment for vaccines and vaccine administration, and acute medical care taking precedence over preventive services. Despite these challenges, a number of strategies have been demonstrated to substantially improve adult vaccine coverage, including patient and provider reminders and standing orders for vaccination. Providers are encouraged to incorporate routine assessment of their adult patients' vaccination needs during all clinical encounters to ensure patients receive recommendations for needed vaccines and are either offered needed vaccines or referred for vaccination.

Varicella Zoster Virus in the Nervous System

Varicella zoster virus (VZV) is a ubiquitous, exclusively human alphaherpesvirus. Primary infection usually results in varicella (chickenpox), after which VZV becomes latent in ganglionic neurons along the entire neuraxis. As VZV-specific cell-mediated immunity declines in elderly and immunocompromised individuals, VZV reactivates and causes herpes zoster (shingles), frequently complicated by postherpetic neuralgia. VZV reactivation also produces multiple serious neurological and ocular diseases, such as cranial nerve palsies, meningoencephalitis, myelopathy, and VZV vasculopathy, including giant cell arteritis, with or without associated rash. Herein, we review the clinical, laboratory, imaging, and pathological features of neurological complications of VZV reactivation as well as diagnostic tests to verify VZV infection of the nervous system. Updates on the physical state of VZV DNA and viral gene expression in latently infected ganglia, neuronal, and primate models to study varicella pathogenesis and immunity are presented along with innovations in the immunization of elderly individuals to prevent VZV reactivation.

Anti-Infectious Human Vaccination in Historical Perspective

A brief history of vaccination is presented since the Jenner's observation, through the first golden age of vaccinology (from Pasteur's era to 1938), the second golden age (from 1940 to 1970), until the current period. In the first golden age, live, such as Bacille Calmette Guérin (BCG), and yellow fever, inactivated, such as typhoid, cholera, plague, and influenza, and subunit vaccines, such as tetanus and diphtheria toxoids, have been developed. In the second golden age, the cell culture technology enabled polio, measles, mumps, and rubella vaccines be developed. In the era of modern vaccines, in addition to the conjugate polysaccharide, hepatitis A, oral typhoid, and varicella vaccines, the advent of molecular biology enabled to develop hepatitis B, acellular pertussis, papillomavirus, and rotavirus recombinant vaccines. Great successes have been achieved in the fight against infectious diseases, including the smallpox global eradication, the nearly disappearance of polio, the control of tetanus, diphtheria, measles, rubella, yellow fever, and rabies. However, much work should still be done for improving old vaccines, such as BCG, anthrax, smallpox, plague, or for developing effective vaccines against old or emerging infectious threats, such as human-immunodeficiency-virus, malaria, hepatitis C, dengue, respiratory-syncytial-virus, cytomegalovirus, multiresistant bacteria, Clostridium difficile, Ebola virus. In addition to search for innovative and effective vaccines and global infant coverage, even risk categories should adequately be protected. Despite patients under immunosuppressive therapy are globally increasing, their vaccine coverage is lower than recommended, even in developed and affluent countries.

Zeroing in on zoster: A tale of many disorders produced by one virus

While herpes zoster infection has been recognized since antiquity, chickenpox (varicella) was confused with smallpox until the 1800s, when both illnesses became better understood. In the 20th century, varicella zoster virus (VZV) was shown to cause varicella upon primary (first-time) infection and herpes zoster (shingles) after reactivation of latent VZV. Scientific progress over the past 50 years has rapidly advanced the understanding and prevention of disease produced by VZV. Combined imaging and virological studies continue to reveal the protean neurological, ocular and visceral disorders produced by VZV.

A novel HSV-2 subunit vaccine induces GLA-dependent CD4 and CD8 T cell responses and protective immunity in mice and guinea pigs

BACKGROUND/OBJECTIVES

There is currently no licensed prophylactic or therapeutic vaccine for HSV-2 infection.

METHODS

We developed a novel preclinical vaccine candidate, G103, consisting of three recombinantly expressed HSV-2 proteins (gD and the UL19 and UL25 gene products) adjuvanted with the potent synthetic TLR4 agonist glucopyranosyl lipid A (GLA) formulated in stable emulsion. The vaccine was tested for immunogenicity and efficacy in pre-clinical models for preventative and therapeutic vaccination.

RESULTS

Vaccination of mice with G103 elicited antigen-specific binding and neutralizing antibody responses, as well as robust CD4 and CD8 effector and memory T cells. The T cell responses were further boosted by subsequent challenge with live virus. Prophylactic immunization completely protected against lethal intravaginal HSV-2 infection in mice, with only transient replication of virus in the genital mucosa and sterilizing immunity in dorsal root ganglia. Supporting the use of G103 therapeutically, the vaccine expanded both CD4 and CD8 T cells induced in mice by previous infection with HSV-2. In the guinea pig model of recurrent HSV-2 infection, therapeutic immunization with G103 was approximately 50% effective in reducing the number of lesions per animal as well as the overall lesions score.

CONCLUSIONS

Taken together, the data show that G103 is a viable candidate for development of a novel prophylactic and therapeutic HSV-2 vaccine.

Vaccinations in patients with hematological malignancies

Patients with hematological malignancies are at risk for a number of infections that are potentially preventable by vaccinations such as pneumococcal infections and influenza. Treatment, especially with anti-B-cell antibodies and hematopoietic stem cell transplantation (HSCT), negatively impacts the response to vaccination for several months. It is therefore recommended that patients be vaccinated before initiating immunosuppressive therapy if possible. The risk of side-effects with inactivated vaccines is low, but care has to be taken with live vaccines, such as varicella-zoster virus vaccine, since severe and fatal complications have been reported. HSCT patients require repeated doses of most vaccines to achieve long-lasting immune responses. New therapeutic options for patients with hematological malignancies that are rapidly being introduced into clinical practice will require additional research regarding the efficacy of vaccinations. New vaccines are also in development that will require well-designed studies to ascertain efficacy and safety.

Viral O-GalNAc peptide epitopes: a novel potential target in viral envelope glycoproteins

Viral envelope glycoproteins are major targets for antibodies that bind to and inactivate viral particles. The capacity of a viral vaccine to induce virus-neutralizing antibodies is often used as a marker for vaccine efficacy. Yet the number of known neutralization target epitopes is restricted owing to various viral escape mechanisms. We expand the range of possible viral glycoprotein targets, by presenting a previously unknown type of viral glycoprotein epitope based on a short peptide stretch modified with small O-linked glycans. Besides being immunologically active, these epitopes have a high potential for antigenic variation. Thus, sera from patients infected with EBV develop individual IgG responses addressing the different possible glycopeptide glycoforms of one short peptide backbone that reflect individual variations in the course of virus infection. In contrast, in HSV type 2 meningitis patients, CSF antibodies are focussed to only one single glycoform peptide of a major viral glycoprotein. Thus, dependent on the viral disease, the serological response may be variable or constant with respect to the number of targeted peptide glycoforms. Mapping of these epitopes relies on a novel three-step procedure that identifies any reactive viral O-glycosyl peptide epitope with respect to (i) relevant peptide sequence, (ii) the reactive glycoform out of several possible glycopeptide isomers of that peptide sequence, and (iii) possibly tolerated carbohydrate or peptide structural variations at glycosylation sites. In conclusion, the viral O-glycosyl peptide epitopes may be of relevance for development of subunit vaccines and for improved serodiagnosis of viral diseases. Copyright © 2015 John Wiley & Sons, Ltd.