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Development of a Novel Method for Deriving Thresholds of Toxicological Concern (TTCs) for Vaccine ConstituentsWhite, Jennifer Jessica 01 January 2013 (has links)
Abstract
Safety assessment relating to the presence of impurities, residual materials and contaminants in vaccines is a focus area of research at the United States Food and Drug Administration (FDA). Sponsors who submit Investigational New Drug (IND) applications for new vaccine products must report the results of safety assessments to the Division of Vaccines and Related Products Applications (DVRPA). Scientifically defining thresholds of toxicological concern (TTCs) as they apply to vaccine constituents will provide a useful aid to the sponsors and public regarding safety assessments of compounds for which there is little or no toxicity data. TTCs are mathematically modeled and extrapolated levels, below which adverse human health effects are not expected to occur (Kroes, 2004). In this project, we accessed DVRPA's submission databases and open source data to yield an initial chemical test set. Using INCHEM, RepDose, RTECS and TOXNET, we gathered LD50 and TDLo data.
Using a structure-based decision tree, provided in the ToxTree software package, (3) different algorithms (The Cramer extended, the In vivo rodent micronucleus assay, and the Benigni-Bossa rule base for carcinogenicity by ISS) were applied to assign the initial test set (n= 197) of chemicals into structural families based on structural alerts (SAs). This resulted in six (6) potential methods for elucidating TTCs: In vivo rodent micronucleus assay/ LD50, Benigni-Bossa/ LD50, Cramer extended/ LD50, In vivo rodent micronucleus assay/ TDLo, Benigni-Bossa/ TDLo, and the Cramer extended/ TDLo.
After each algorithm designated two structural families each, the distribution of TDLo's and LD50's for each structural family was subjected to a preliminary data analysis using JMP statistical software version 9. Based on an analysis of quantiles, skew, and kurtosis, it was concluded that the TDLo dataset was of poor quality and was dropped from further analysis, and that the In vivo rodent micronucleus assay algorithm failed to partition the initial test set in a meaningful way, so it too was culled from further consideration. This resulted in (2) remaining TTC methods for further consideration: Benigni-Bossa/ LD50 and the Cramer extended/ LD50.
The remaining methods were subjected to internal validation based on Gene-Tox, CCRIS, CPDB, IARC, and EPA classaifications for genotoxic mutagenicity and carcinogenicity. Validation parameters were calculated for both methods and it was determined that the Benigni-Bossa/ LD50 method outperformed the Cramer extended/ LD50 method in terms of specificity (87.2 vs. 48.1%#37;), accuracy (65.2 vs. 52.94%#37;), positive predictivity (66.6 vs. 50%#37;), negative predictivity (64.8 vs. 56.5%#37;), ROC+ (2 vs. 1) and ROC- (1.84 vs. 1.3). These results indicated that the Benigni-Bossa/ LD50 was the most appropriate for calculating TTCs for vaccine constituents.
For each class, the lower 2.5th percentile LD50 was extrapolated to a TTC value using safety estimates derived using uncertainty factors (UF) and adjusting for adult human weight. Final TTCs were designated as 18.06 μg/ person and 20.616 μg/ person for the Benigni-Bossa positive and negative structural families.
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Contagious bovine pleuropneumonia (CBPP) in the Maasai ecosystem of south-western Kenya : evaluation of seroprevalence, risk factors and vaccine safety and efficacyMtui-Malamsha, Niwael Jesse January 2009 (has links)
Contagious bovine pleuropneumonia (CBPP) is a bovine bacterial disease of major economic importance in sub-Saharan Africa. Vaccination has been recommended to control the disease in endemic areas such as the Maasai ecosystems of Kenya and Tanzania; however, the currently used live attenuated vaccine has been reported to have poor vaccine safety and efficacy. To compare standard (current) and an improved (buffered) version of the live CBPP-vaccine, several epidemiological studies were carried out in Maasai cattle in Kenya between 2006 and 2008. Specifically, the aims were to estimate CBPP seroprevalence at herd and animal level; to identify risk factors for seroprevalence at both levels; to investigate the spatial distribution of seroprevalence; to compare post vaccination adverse events in cattle vaccinated with a standard and a buffered vaccine, and finally to compare efficacy of the two vaccines to induce seroconversion and to prevent development of clinical signs suggestive of CBPP. A cross-sectional study was carried out in 6872 cattle in 175 randomly selected herds from Loita and Mara divisions. A competitive ELISA revealed that 85% of the herds in the area had at least one seropositive animal and that seropositive herds were harbouring 11% seropositive cattle. A complement fixation test revealed that 46% of the herds had at least one seropositive animal and that seropositive herds were harbouring 4% seropositive cattle. A multivariable logistic regression analysis of the seroprevalence indicated that previous vaccination against CBPP, a history of CBPP outbreaks in the herd, animal age and the location of the herd in the division of Mara were positively correlated to seroprevalence. To investigate the observed difference in herd seroprevalence between the two divisions further, a spatial analysis was conducted. A SatScan test revealed clusters in Mara in areas identified by veterinary personnel as CBPP ‘hot spots’. A logistic regression using spatial information identified that location in the midland agro-ecological zone or close to a river and vaccination were positively associated with seroprevalence. To compare safety and efficacy of a standard and a buffered vaccine, two cohorts of approximately 40,000 cattle were used. The study showed that within 100 days post vaccination, 6.2 cattle per 1000 vaccinates developed adverse events, 4.1 of which were specifically attributable to vaccination and ranging from swelling of the tail to the tail sloughing off. This study revealed a slightly higher incidence of adverse events in cattle vaccinated with the buffered vaccine compared to the standard vaccine. A comparison of the efficacy of the two vaccines revealed that cattle vaccinated with the buffered vaccine had higher odds of seroconversion and lower odds of developing symptoms of CBPP, three and twelve months post vaccination respectively. The epidemiological studies conducted clearly show wide spread seroprevalence in the Maasai cattle. Given the (spatial) heterogeneity observed, control measures should probably be targeted in areas of increased risk (clusters). However, positive association of vaccination and seropositivity call for better diagnostics tests that can differentiate vaccinated from infected animals. Vaccination with buffered vaccine resulted in increased seroconversion, decreased clinical signs indicative of CBPP post vaccination and low seroprevalence post ‘outbreak’. Nevertheless, the increase in adverse events related to the buffered vaccine calls for further research into safer CBPP vaccines.
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The Use and Neurological Safety of the Quadrivalent Human Papillomavirus (HPV) Vaccine: The Ontario Grade 8 HPV Vaccine Cohort StudyLim, Wen Ting 28 September 2012 (has links)
The quadrivalent (q-) human papillomavirus (HPV) vaccine is praised for its near perfect efficacy of 98% in the per-protocol population and minimal safety concerns. Adherence to the dosing schedule of 0, 2 and 6 months outside clinical trials has not yet been described. Furthermore, clinical trials were underpowered to detect rare, but serious, adverse events including convulsions, seizures and epilepsy in young girls targeted by American and Canadian national advisory committees.
This retrospective cohort study followed Grade 8 girls eligible for Ontario’s HPV immunization program during the 2007/08 to 2010/11 campaign years. Using Ontario’s immunization and health databases, baseline characteristics, qHPV vaccination, dates of qHPV vaccination and diagnoses of serious neurological events were identified for each cohort member. The proportions of girls who initiated and completed the qHPV vaccine program were determined. Adherence to the recommended dosing intervals and for ‘time-to-series completion’ was calculated as the proportion of eligible girls whose number of days between doses complied with the recommended dosing interval. A self-matched, case only approach was used to estimate the age-adjusted rate ratio (RR) of neurological events in the 0-30 day period following qHPV vaccination. The primary study endpoint was a composite of the first occurrence of a convulsion, seizure or epilepsy. Secondarily, an epileptic seizure only endpoint was assessed, as were the influence of a number of predisposing risk factors.
An overall uptake of 50.24% was observed, of which, 87.02% received at least three doses. Adherence to the recommended dosing interval was most difficult in scheduling of the second dose (70.80%). There was no increased risk observed for the primary endpoint in the 0-30 days following qHPV vaccination (RR 1.01, 95% CI 0.92-1.10). However, this association was modified in girls with predisposing risk factors for epilepsy. There was an increased risk observed for the epileptic seizure only endpoint (RR 1.64, 95% CI 1.28-2.10).
In Ontario, the overall uptake of the qHPV vaccine is low. Once initiated, series completion is high, with the majority receiving the vaccine in a timely manner. A risk for epileptic seizures following vaccination may be limited to girls with predisposing risk factors. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2012-09-28 17:56:59.608
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Methodological Approaches to Studying Risk Factors for Adverse Events Following Routine Vaccinations in the General Population and Vulnerable Subgroups of Individuals Using Health Administrative DataHawken, Steven January 2014 (has links)
Objectives: This thesis included 6 manuscripts which focused on the analysis of adverse events following immunization (AEFIs), including general health services utilization (emergency room (ER) visits and hospital admissions) and specific diagnoses (e.g. febrile convulsions). The main objectives of this research were: 1) To demonstrate the utility of the self-controlled case series (SCCS) design coupled with health administrative data for studying the safety of vaccines; 2) Introducing an innovative approach using relative incidence ratios (RIRs) within an SCCS analysis to identify risk factors for AEFIs and to overcome the healthy vaccinee bias; and 3) To demonstrate how SCCS and RIR analyses of health services outcomes in health administrative data can provide important insights into underlying physiological and behavioural mechanisms.
Data Sources: This work utilized Ontario health administrative data housed at the Institute for Clinical Evaluative Sciences (ICES). The study included all children born in Ontario, Canada between 2002 and 2011 (over 1 million children). Vaccinations were identified using OHIP fee for service billing codes for general vaccination. Admissions and ER visits for any reason were identified in the Discharge Abstract Database (DAD) and National Ambulatory Care Reporting System (NACRS). Primary reasons for admissions and ER visits were investigated using ICD-10-CA codes reported in the DAD and NACRS databases.
Statistical Methods: The self-controlled case series design (SCCS) was used to calculate the relative incidence of admissions, ER visits and other AEFIs. To investigate relative incidence for AEFIs across risk groups of interest, as well as addressing the healthy vaccinee effect bias, RIRs were calculated. RIRs are the ratio of incidence ratios in a subgroup of interest relative to a designated reference group.
Results and Conclusions: The combined approach of using the SCCS design and RIRs to identify risk factors and overcome the healthy vaccinee bias proved to be a powerful approach to studying vaccine safety. Future work will be important to characterize the performance and validity of the SCCS + RIR approach in the presence of increasing levels of confounding and differing manifestations of the healthy vaccinee bias, as well as to elucidate the biological and behavioural mechanisms underlying our findings.
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ASSESSING THE RISK FOR AUTOIMMUNE DISORDERS FOLLOWING USE OF THE QUADRIVALENT HUMAN PAPILLOMAVIRUS VACCINE: THE ONTARIO GRADE 8 HPV VACCINE COHORT STUDYLiu, Yiran 24 April 2014 (has links)
Introduction: In 2007 Ontario implemented a grade 8 quadrivalent human papillomavirus (qHPV) vaccination program targeting the virus that causes cervical cancer. Despite being 6 years post-implementation, few post-licensure studies have assessed the safety of the qHPV vaccine in this adolescent population. Since autoimmune disorders are often targeted for post-marketing surveillance by regulatory agencies, it is important to assess the risk of developing an autoimmune disorder post-qHPV vaccination.
Objectives: The objectives of this thesis were to assess the risk for developing an autoimmune disorder following qHPV vaccination, assess for effect modification by the presence of predisposing risk factors, identify the period of highest risk and explore the risk for individual autoimmune disorders.
Methods: A population-based retrospective cohort of girls eligible for Ontario’s qHPV vaccination program was identified using population-based databases. The risk of autoimmune disorders following qHPV vaccination was ascertained using the self-controlled case series method.
Results: The risk of developing a new autoimmune disorder, adjusted for age, seasonality, concurrent vaccines and infections was 1.28 (95% CI: 0.87 – 1.89), and this association was independent of a history of immune-mediated disorders (p=0.39). The risk was not increased during days 7-24 post-vaccination (adjusted RR = 0.87, 95% CI: 0.43 – 1.74), but appeared to increase thereafter (adjusted RR = 1.36, 95% CI: 0.77 – 2.41 and RR = 1.62, 95% CI 0.94 – 2.78 respectively, for days 25 – 42 and days 43 – 60), although these differences were non-significant. The risk may be increased for certain disorders including Bell’s palsy (RR = 2.30, 95% CI: 0.67 – 7.95), systemic autoimmune rheumatic disorders (RR = 1.84, 95% CI: 0.42 – 8.02), Hashimoto’s disease (RR = 1.39, 95% CI: 0.46 – 4.22), and juvenile rheumatoid arthritis (RR = 1.31, 95% CI: 0.83 – 2.08), although none of these associations were statistically significant.
Conclusion: This thesis demonstrated that no statistically significant increased risk for autoimmune disorders following qHPV vaccination was detected. However, there remains some uncertainty about the safety of the qHPV vaccine for a subset of the autoimmune disorders. The results from this analysis need to be pooled with those of other studies to confirm whether these are true safety signals. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2014-04-23 22:30:41.428
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Análise da segurança e da imunogenicidade da vacina influenza sazonal trivalente (fragmentada e inativada) integralmente produzida pelo Instituto Butantan em 2013, 2014 e 2015 / Safety and immunogenicity of a seasonal trivalent inactivated influenza vaccine produced by Butantan Institute in 2013, 2014 e 2015Mondini, Gabriella 17 July 2018 (has links)
INTRODUÇÃO: A vacinação anual é recomendada como a medida mais efetiva contra a influenza sazonal. O Instituto Butantan (IB) realizou, anualmente, estudos clínicos das vacinas influenza sazonais trivalentes (fragmentada e inativada), produzidas em2013, 2014 e 2015. MÉTODO: Estudos de coorte prospectivos para descrever a imunogenicidade e a segurança da vacina influenza produzida pelo IB nos anos de 2013, 2014 e 2015 em participantes adultos saudáveis e idosos. Após assinatura do TCLE os participantes foram submetidos à coleta de sangue e receberam uma dose da vacina. Nos dias 1, 2 e 3 após a vacinação foram contatados para avaliação da segurança (reações adversas solicitadas locais e sistêmicas e não solicitadas). No dia 21(+7) pósvacinação retornaram ao centro de pesquisa para nova checagem da segurança e para a coleta de sangue para a avaliação da imunogenicidade pós-vacinação. As análises de imunogenicidade foram feitas através do método inibição de hemaglutinação (IH). Os desfechos de imunogenicidade foram: porcentagem de soroconversão (SC), porcentagem de soroproteção (SP) e razão da média geométrica dos títulos (RMGT) de anticorpos inibidores da hemaglutinação. O estudo de 2013 foi conduzido no Centro de Referência para Imunobiológicos Especiais (CRIE) e no Centro de Pesquisa Clínica do Instituto da Criança, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, os estudos de 2014 e 2015 foram realizados apenas no CRIE. As composições das vacinas utilizadas nos estudos em 2013, 2014 e 2015 seguiram as recomendações da OMS para vacina influenza sazonal do hemisfério sul. RESULTADOS: No ano de 2013, foram incluídos no estudo 47 adultos e 13 idosos, em 2014, 60 adultos e 60 idosos e em 2015, 62 adultos e 57 idosos. Nos estudos de 2013, 2014 e 2015, dor foi a reação adversa local mais frequente e cefaleia a sistêmica mais relatada. Todas as reações adversas observadas foram classificadas como leves ou moderadas e nenhuma como grave. Porcentagens de SP > 70% e >60% foram demonstradas para adultos e idosos, respectivamente, para os três vírus vacinais, nos estudos de 2013, 2014 e 2015. Porcentagem de SC > 40% foi demonstrada para os adultos, para os três vírus vacinais, apenas no estudo de 2014 e porcentagem de SC >30% foi demonstrada nos idosos, para os três vírus vacinais, apenas nos estudos de 2013 e 2014. RMGT > 2.5 nos adultos para os três vírus vacinais foi demonstrada apenas no estudo de 2013 e RMGT > 2 nos idosos, para os três vírus vacinais, foi demonstrada nos estudos de 2013, 2014 e 2015. CONCLUSÃO: As vacinas influenza sazonal de 2013, 2014 e 2015, produzidas integralmente pelo Instituto Butantan, foram seguras e imunogênicas segundo os parâmetros de imunogenicidade definidos pela EMA / INTRODUCTION: Annual vaccination is most effective way to prevent seasonal influenza illness. Instituto Butantan (IB) performed clinical studies with its 2013, 2014 and 2015 seasonal trivalent influenza vaccines (split-virion and inactivated) METHODS: Prospective cohort studies to describe the safety and immunogenicity of Instituto Butantan influenza vaccine, in healthy adults and elderly, from 2013 to 2015. Soon after the informed consent was signed, participants underwent blood collection followed by vaccination. On study days 1, 2 and 3 post vaccination participants were contacted by the stuffy to evaluate the occurrence of solicited (local and systemic) and non-solicited adverse reactions. On study day 21(+7) subjects returned to the clinical site for final safety assessments and blood collection for the immunogenicity evaluation post vaccination. The immunogenicity analyses were performed by means of haemagglutination inhibition assay (HI). The immunogenicity endpoints were: seroprotection (SPR) and seroconversion (SCR) rates and the geometric mean HI antibody titer ratio (GMTR). The 2013 study The Centro de Referência para Imunobiológicos Especiais (CRIE) and at the Centro de Pesquisa Clínica do Instituto da Criança, Hospital das Clínicas of Medical School of University of São Paulo and the 2014 and 2015 studies were conducted at CRIE. The vaccine composition followed the WHO recommendation for the southern hemisphere seasonal influenza vaccine RESULTS: 47 healthy adults and 13 elderly participated in the 2013 study, 60 healthy adults and 60 elderly in the 2014 study, and 62 healthy adults and 57 elderly in the 2015 study. In the 2013, 2014 and 2015 studies, pain was the most frequent local adverse reaction and headache the most frequent systemic adverse reaction. All observed adverse reactions were classified as mild or moderate and none as severe. SPR > 70% and SPR > 60% were observed in adults and elderly, respectively, for the three vaccine viruses, in the 2013, 2014 and 2015 studies. SCR > 40% was observed in adults, for the three vaccine viruses, only in the 2014 study and SCR > 30% was observed in elderly, for the three vaccine viruses, only in the 2013 and 2014 studies. GMTR >2.5 among adults, for the three vaccine viruses was only observed in the 2013 study and GMTR > 2.0 was observed among elderly, for the three vaccine viruses, in the 2013, 2014 and 2015 studies. CONCLUSION: The 2013, 2014 and 2015 seasonal influenza vaccines produced by Instituto Butantan were safe and immunogenic according to the immunogenicity criteria defined by EMA
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Análise da segurança e da imunogenicidade da vacina influenza sazonal trivalente (fragmentada e inativada) integralmente produzida pelo Instituto Butantan em 2013, 2014 e 2015 / Safety and immunogenicity of a seasonal trivalent inactivated influenza vaccine produced by Butantan Institute in 2013, 2014 e 2015Gabriella Mondini 17 July 2018 (has links)
INTRODUÇÃO: A vacinação anual é recomendada como a medida mais efetiva contra a influenza sazonal. O Instituto Butantan (IB) realizou, anualmente, estudos clínicos das vacinas influenza sazonais trivalentes (fragmentada e inativada), produzidas em2013, 2014 e 2015. MÉTODO: Estudos de coorte prospectivos para descrever a imunogenicidade e a segurança da vacina influenza produzida pelo IB nos anos de 2013, 2014 e 2015 em participantes adultos saudáveis e idosos. Após assinatura do TCLE os participantes foram submetidos à coleta de sangue e receberam uma dose da vacina. Nos dias 1, 2 e 3 após a vacinação foram contatados para avaliação da segurança (reações adversas solicitadas locais e sistêmicas e não solicitadas). No dia 21(+7) pósvacinação retornaram ao centro de pesquisa para nova checagem da segurança e para a coleta de sangue para a avaliação da imunogenicidade pós-vacinação. As análises de imunogenicidade foram feitas através do método inibição de hemaglutinação (IH). Os desfechos de imunogenicidade foram: porcentagem de soroconversão (SC), porcentagem de soroproteção (SP) e razão da média geométrica dos títulos (RMGT) de anticorpos inibidores da hemaglutinação. O estudo de 2013 foi conduzido no Centro de Referência para Imunobiológicos Especiais (CRIE) e no Centro de Pesquisa Clínica do Instituto da Criança, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, os estudos de 2014 e 2015 foram realizados apenas no CRIE. As composições das vacinas utilizadas nos estudos em 2013, 2014 e 2015 seguiram as recomendações da OMS para vacina influenza sazonal do hemisfério sul. RESULTADOS: No ano de 2013, foram incluídos no estudo 47 adultos e 13 idosos, em 2014, 60 adultos e 60 idosos e em 2015, 62 adultos e 57 idosos. Nos estudos de 2013, 2014 e 2015, dor foi a reação adversa local mais frequente e cefaleia a sistêmica mais relatada. Todas as reações adversas observadas foram classificadas como leves ou moderadas e nenhuma como grave. Porcentagens de SP > 70% e >60% foram demonstradas para adultos e idosos, respectivamente, para os três vírus vacinais, nos estudos de 2013, 2014 e 2015. Porcentagem de SC > 40% foi demonstrada para os adultos, para os três vírus vacinais, apenas no estudo de 2014 e porcentagem de SC >30% foi demonstrada nos idosos, para os três vírus vacinais, apenas nos estudos de 2013 e 2014. RMGT > 2.5 nos adultos para os três vírus vacinais foi demonstrada apenas no estudo de 2013 e RMGT > 2 nos idosos, para os três vírus vacinais, foi demonstrada nos estudos de 2013, 2014 e 2015. CONCLUSÃO: As vacinas influenza sazonal de 2013, 2014 e 2015, produzidas integralmente pelo Instituto Butantan, foram seguras e imunogênicas segundo os parâmetros de imunogenicidade definidos pela EMA / INTRODUCTION: Annual vaccination is most effective way to prevent seasonal influenza illness. Instituto Butantan (IB) performed clinical studies with its 2013, 2014 and 2015 seasonal trivalent influenza vaccines (split-virion and inactivated) METHODS: Prospective cohort studies to describe the safety and immunogenicity of Instituto Butantan influenza vaccine, in healthy adults and elderly, from 2013 to 2015. Soon after the informed consent was signed, participants underwent blood collection followed by vaccination. On study days 1, 2 and 3 post vaccination participants were contacted by the stuffy to evaluate the occurrence of solicited (local and systemic) and non-solicited adverse reactions. On study day 21(+7) subjects returned to the clinical site for final safety assessments and blood collection for the immunogenicity evaluation post vaccination. The immunogenicity analyses were performed by means of haemagglutination inhibition assay (HI). The immunogenicity endpoints were: seroprotection (SPR) and seroconversion (SCR) rates and the geometric mean HI antibody titer ratio (GMTR). The 2013 study The Centro de Referência para Imunobiológicos Especiais (CRIE) and at the Centro de Pesquisa Clínica do Instituto da Criança, Hospital das Clínicas of Medical School of University of São Paulo and the 2014 and 2015 studies were conducted at CRIE. The vaccine composition followed the WHO recommendation for the southern hemisphere seasonal influenza vaccine RESULTS: 47 healthy adults and 13 elderly participated in the 2013 study, 60 healthy adults and 60 elderly in the 2014 study, and 62 healthy adults and 57 elderly in the 2015 study. In the 2013, 2014 and 2015 studies, pain was the most frequent local adverse reaction and headache the most frequent systemic adverse reaction. All observed adverse reactions were classified as mild or moderate and none as severe. SPR > 70% and SPR > 60% were observed in adults and elderly, respectively, for the three vaccine viruses, in the 2013, 2014 and 2015 studies. SCR > 40% was observed in adults, for the three vaccine viruses, only in the 2014 study and SCR > 30% was observed in elderly, for the three vaccine viruses, only in the 2013 and 2014 studies. GMTR >2.5 among adults, for the three vaccine viruses was only observed in the 2013 study and GMTR > 2.0 was observed among elderly, for the three vaccine viruses, in the 2013, 2014 and 2015 studies. CONCLUSION: The 2013, 2014 and 2015 seasonal influenza vaccines produced by Instituto Butantan were safe and immunogenic according to the immunogenicity criteria defined by EMA
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