Safety and immunogenicity of Px563L,a recombinant anthrax vaccine candidate,in a two-dose regimen for post-exposure prophylaxis in healthy adults

Px563L is a next-generation anthrax vaccine candidate consisting of a protein subunit, mutant recombinant protective antigen SNKE167-ΔFF-315-E308D (mrPA), and liposome-embedded monophosphoryl lipid A (MPLA) adjuvant. Px563L has the potential to deliver an improved safety and immunogenicity profile relative to the currently licensed vaccine, which is produced from filtered B. anthracis culture supernatants.We conducted a Phase 1, double–blind, placebo–controlled, dose–escalation study in 54 healthy subjects to evaluate Px563L at 3 dose levels of mrPA (10, 50, and 80 mcg). For each dose level, 18 subjects were randomized in an 8:8:2 ratio to Px563L (mrPA with adjuvant), RPA563 (mrPA only) or placebo (saline). Each subject received an intramuscular (IM) injection on Day 0 and Day 28. Primary safety and immunogenicity analysis was conducted after all subjects completed the Day 70 visit, a duration deemed clinically relevant for post-exposure prophylaxis. Long-term safety was assessed through Day 393.Vaccinations with Px563L at all dose levels were well-tolerated. There were no serious adverse events or adverse events (AE) leading to early withdrawal. In all treatment groups, most AEs were due to injection site reactions, and all AEs at the 10 and 50 mcg dose levels were mild. For the primary immunogenicity endpoint (protective toxin neutralizing antibody 50% neutralization factor [TNA NF₅₀]), titers started to increase significantly after the second administration of Px563L, from Day 35 through Day 70, with the geometric mean and lower bound of the 95% confidence interval exceeding 0.56, a threshold correlating with significant survival in animal models of anthrax exposure.In conclusion, Px563L, administered as two IM doses 28 days apart, was well-tolerated and elicited a protective antibody response starting at seven days after the second vaccination. These findings support the continued development of Px563L in a two-dose regimen for anthrax post-exposure prophylaxis. ClinicalTrials.gov identifier NCT02655549.     

Variability in non-core vaccination rates of dogs and cats in veterinary clinics across the United States

Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases.     

Uptake and timeliness of rotavirus vaccination in Norway: The first year post-introduction

BackgroundTo minimise vaccine-associated risk of intussusception following rotavirus vaccination, Norway adopted very strict age limits for initiating and completing the vaccine series at the time rotavirus vaccination was included in the national immunisation programme, October 2014. Although Norway has a high coverage for routine childhood vaccines, these stringent age limits could negatively affect rotavirus coverage. We documented the status and impact of rotavirus vaccination on other infant vaccines during the first year after its introduction.MethodsWe used individual vaccination data from the national immunisation register to calculate coverage for rotavirus and other vaccines and examine adherence with the recommended schedules. We identified factors associated with completing the full rotavirus series by performing multiple logistic regression analyses. We also evaluated potential changes in uptake and timeliness of other routine vaccines after the introduction of rotavirus vaccine using the Kaplan-Meier method.ResultsThe national coverage for rotavirus vaccine achieved a year after the introduction was 89% for one dose and 82% for two doses, respectively. Among fully rotavirus-vaccinated children, 98% received both doses within the upper age limit and 90% received both doses according to the recommended schedule. The child’s age at the initiation of rotavirus series and being vaccinated with diphtheria, tetanus, pertussis, polio and Haemophilus influenzae type b (DTaP/IPV/Hib) and pneumococcal vaccines were the strongest predictors of completing the full rotavirus series. No major changes in uptake and timeliness of other paediatric vaccines were observed after introduction of rotavirus vaccine.ConclusionsNorway achieved a high national coverage and excellent adherence with the strict age limits for rotavirus vaccine administration during the first year of introduction, indicating robustness of the national immunisation programme. Rotavirus vaccination did not impact coverage or timeliness of other infant vaccines.     

Reference set for performance testing of pediatric vaccine safety signal detection methods and systems

BackgroundSafety signal detection in spontaneous reporting system databases and electronic healthcare records is key to detection of previously unknown adverse events following immunization. Various statistical methods for signal detection in these different datasources have been developed, however none are geared to the pediatric population and none specifically to vaccines. A reference set comprising pediatric vaccine-adverse event pairs is required for reliable performance testing of statistical methods within and across data sources.MethodsThe study was conducted within the context of the Global Research in Paediatrics (GRiP) project, as part of the seventh framework programme (FP7) of the European Commission. Criteria for the selection of vaccines considered in the reference set were routine and global use in the pediatric population. Adverse events were primarily selected based on importance. Outcome based systematic literature searches were performed for all identified vaccine-adverse event pairs and complemented by expert committee reports, evidence based decision support systems (e.g. Micromedex), and summaries of product characteristics. Classification into positive (PC) and negative control (NC) pairs was performed by two independent reviewers according to a pre-defined algorithm and discussed for consensus in case of disagreement.ResultsWe selected 13 vaccines and 14 adverse events to be included in the reference set. From a total of 182 vaccine-adverse event pairs, we classified 18 as PC, 113 as NC and 51 as unclassifiable. Most classifications (91) were based on literature review, 45 were based on expert committee reports, and for 46 vaccine-adverse event pairs, an underlying pathomechanism was not plausible classifying the association as NC.ConclusionA reference set of vaccine-adverse event pairs was developed. We propose its use for comparing signal detection methods and systems in the pediatric population.     

Fear,mistrust, and vaccine hesitancy: Narratives of the dengue vaccine controversy in the Philippines

This article applies a qualitative approach to the 2017 dengue vaccine controversy involving Sanofi Pasteur’s Dengvaxia to understand vaccine hesitancy and related anxieties in contemporary Philippines. Through a multisited project that investigated the health aspirations and lived experiences of low- and middle-income Filipinos across urban and rural Philippines, this article distills the perspectives of both ordinary community members and health workers in local and national capacities regarding the controversy—and how it altered their perceptions toward vaccines, health care, and government. Our study reveals widespread mistrust and fear in the communities toward both the state and health institutions following the controversy, with frontline health workers bearing the brunt of the communities’ apprehensions, and the media partly responsible in fomenting these fears. Given the repetitive nature of health and vaccine controversies, this article suggests the importance of responsible journalism, well-calibrated crisis communications, and a people-centered health paradigm that involves exploring local contexts of vaccine hesitancy and mining people’s lived experiences in tackling present and future health crises—especially now in the advent of COVID-19 vaccinations.     

The role of National Immunization Technical Advisory Groups (NITAG) in strengthening health system governance: Lessons from three middle-income countries—Argentina,Jordan, and South Africa (2017–2018)

IntroductionToward the Global Vaccine Action Plan 2020 goal, almost 90% of countries have established a National Immunization Technical Advisory Group (NITAG). However, little is known about NITAG's contributions to governance.MethodsIn 2017–2018, a two-step, qualitative retrospective study was conducted. Jordan (JO), Argentina (AR), and South Africa (SA) were selected owing to government-financed NITAGs from middle-income countries (MICs), geographic diversity, and a vaccine introduction with NITAG support. Country case studies were developed, collecting data through desk review and face-to-face key informant interviews (KIIs) from Ministry of Health (MoH) and NITAG. Case studies were analyzed together, to assess governance applying the European Observatory on Health Systems and Policies framework focusing on transparency, accountability, participation, integrity, and policy capacity (TAPIC).ResultsDocument review and 53 KII (22 AR, 20 SA, 11 JO) showed NITAGs played a pivotal role as advisors promoting a culture of evidence-informed policies. NITAGs strengthened governance, although practices varied among countries. Meetings were conducted behind-closed-doors, participation restricted to members, only in one country agendas, and recommendations were public (AR). To increase participation, policy capacity, and transparency, countries considered adding experts in communications, advocacy, and economics. AR and SA contemplated including community members. NITAGs functioned autonomously from the government, with no established internal or external monitoring or supervision. NITAG meeting minutes allowed the review of integrity, adherence to terms of reference, standard operating procedures, and conflict of interest (CoI). For the most part, NITAGs abided by their mandates. Significant issues were related to the level of MoH support and oversight of CoI declaration and documentation.ConclusionsSystematically implementing governance approaches could improve processes, better tailor policies, and implementation. The long-term survival and resilience of NITAGs in these countries showed they play a significant role in strengthening governance. Lessons learned could be useful to those promoting country-driven evidence-informed decision-making.     

Increase in Streptococcus pneumoniae serotype 3 associated parapneumonic pleural effusion/empyema after the introduction of PCV13 in Germany

IntroductionPediatric pneumococcal pneumonia complicated by parapneumonic pleural effusion/empyema (PPE/PE) remains a major concern despite general immunization with pneumococcal conjugate vaccines (PCVs).MethodsIn a nationwide pediatric hospital surveillance study in Germany we identified 584 children <18 years of age with bacteriologically confirmed PPE/PE from October 2010 to June 2018. Streptococcus pneumoniae was identified by culture and/or PCR of blood samples and/or pleural fluid and serotyped.ResultsS. pneumoniae was identified in 256 of 584 (43.8%) children by culture (n = 122) and/or PCR (n = 207). The following pneumococcal serotypes were detected in 114 children: serotype 3 (42.1%), 1 (25.4%), 7F (12.3%), 19A (7.9%), other PCV13 serotypes (4.4%) and non-PCV13 serotypes (7.9%). Between October 2010 and June 2014 serotype 1 (38.1%) and serotype 3 (25.4%) were most prevalent, whereas between July 2014 and June 2018 serotype 3 (62.7%) and non-PCV13 serotypes (15.7%) were dominant. Compared to children with other pneumococcal serotypes, children with serotype 3 associated PPE/PE were younger (median 3.2 years [IQR 2.1–4.3 years] vs. median 5.6 years [IQR 3.8–8.2 years]; p < 0.001) and more frequently admitted to intensive care (43 [89.6%] vs. 48 [73.8%]; p = 0.04). Seventy-six of 114 (66.7%) children with pneumococcal PPE/PE had been vaccinated with pneumococcal vaccines. Thirty-nine of 76 (51.3%) had received a vaccine covering the serotype detected. Thirty of these 39 breakthrough cases were age-appropriately vaccinated with PCV13 and considered vaccine failures, including 26 children with serotype 3, three children with serotype 19A and one child with serotype 1.ConclusionFollowing the introduction of PCV13 in general childhood vaccination we observed a strong emergence of serotype 3 associated PPE/PE in the German pediatric population, including a considerable number of younger children with serotype 3 vaccine breakthrough cases and failures. Future PCVs should not only cover newly emerging serotypes, but also include a more effective component against serotype 3.     

Immunisation with the BCG and DTPw vaccines induces different programs of trained immunity in mice

In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.     

Investigating the association of receipt of seasonal influenza vaccine with occurrence of anesthesia/paresthesia and severe headaches,Canada 2012/13–2016/17, the Canadian Vaccine Safety Network

BackgroundConcern about adverse events following immunization is frequently cited by both those who receive or decline vaccines. Neurological adverse events are especially concerning.ObjectivesOur aim was to detect associations between seasonal influenza vaccination and the occurrence of severe anesthesia/paresthesia or severe headaches.MethodsData were analyzed from the Canadian National Vaccine Safety network. Events occuring on days 0–7 were self-reported and prevented daily activity, led to school or work absenteeism, or required medical attention. Controls were the previous year’s vaccinees; events in controls were collected prior to the start of the influenza vaccination program of each year (2012/13 through 2016/17). Multivariable logistic regression was used to determine the association between seasonal influenza vaccination and the occurrence of anesthesia/paresthesia or severe headaches.ResultsThe total sample was 107,565 for investigating anesthesia/paresthesia and 97,420 for investigating severe headaches. Anesthesia/paresthesia was reported by 104/107,565 (0.10%) participants; 63/69,129 (0.09%) vaccinees and 41/38,436 (0.11%) controls (adjusted odds ratio (aOR) = 0.89; 95% CI = 0.60, 1.32). Severe headaches were reported by 1361/97,420 (1.40%) participants; 907/61,463 (1.48%) vaccinees and 454/35,957 (1.26%) controls (aOR = 1.21; 95% CI = 1.08, 1.36). No specific vaccine product was associated with severe headaches.ConclusionsOur study found no association between severe anesthesia/paresthesia and seasonal influenza vaccination. While there was an association with severe headaches as an adverse event following influenza vaccination, the rates of these events are similar to rates reported from clinical trials and are not a cause for additional concern.     

High dose trivalent influenza vaccine compared to standard dose vaccine in patients with rheumatoid arthritis receiving TNF-alpha inhibitor therapy and healthy controls: Results of the DMID 10-0076 randomized clinical trial

IntroductionSubjects with rheumatoid arthritis (RA) receiving tumor necrosis factor-inhibiting (TNFi) therapies are at risk for severe influenza, and may respond less well to influenza vaccine. We examined the safety and immunogenicity of high dose influenza vaccine (HD) compared to standard dose vaccine (SD) in participants with RA receiving stable TNFi.MethodsA randomized, double-blinded, Phase II study was conducted in adults with RA receiving TNFi, and healthy, gender and age-matched control subjects. Participants were immunized with HD (Sanofi Pasteur Fluzone High Dose [60 mcg × 3 strains]) or SD (Sanofi Pasteur Fluzone® [15 mcg × 3 strains]) intramuscularly (IM). A self-administered memory aid recorded temperature and systemic and local adverse events (AEs) for 8 days, and safety was evaluated and serum obtained to measure HAI activity on days 7, 21 and 180 days following vaccination.ResultsA greater proportion of RA subjects who received HD seroconverted at day 21 compared to SD, although this was not statistically significant. GMT antibody responses in RA subjects who received HD compared to SD were greater for all strains on day 21, and this was significant for H1N1. Seroconversion rates and GMT values were not different between RA subjects and control subjects. There were no safety concerns for HD or SD in RA subjects, and RA-related symptoms did not differ between SD and HD recipients by a RA-symptom questionnaire (RAPID 3).ConclusionsTNF-inhibitor therapy in people with RA did not appear to influence the immunogenicity of either SD or HD. Influenza seroconversion and GMT values were higher among RA subjects receiving HD compared to SD; however, differences were small and a larger study is needed to validate these findings. Given the apparent risk of increased influenza-related morbidity and mortality among immune compromised subjects, the higher GMT values generated by HD may be beneficial.