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1.
J Infect Dis ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38853614

RESUMEN

BACKGROUND: We report data from Stage 1 of an ongoing two-staged, phase I/II randomized clinical trial (NCT05073003) with a 4-component Generalized Modules for Membrane Antigens-based vaccine against Shigella sonnei and S. flexneri 1b, 2a and 3a (altSonflex1-2-3, GSK). METHODS: 18-50-year-old Europeans (N=102) were randomized (2:1) to receive two injections of altSonflex1-2-3 or placebo at 3- or 6-month interval. Safety and immunogenicity were assessed at pre-specified timepoints. RESULTS: The most common solicited administration-site event (until 7 days post-each injection) and unsolicited adverse event (until 28 days post-each injection) were pain (altSonflex1-2-3: 97.1%; Placebo: 58.8%) and headache (32.4%; 23.5%), respectively. All serotype-specific functional IgG antibodies peaked 14-28 days post-injection 1 and remained substantially higher than pre-vaccination at 3 or 6 months post-vaccination; the second injection did not boost but restored the initial immune response. The highest seroresponse rates (≥4-fold increase in titers over baseline) were obtained against S. flexneri 2a (ELISA: post-injection 1: 91.0%; post-injection 2 [Day {D}113; D197]: 100%; 97.0%; serum bactericidal activity (SBA): post-injection 1: 94.4%; post-injection 2: 85.7%; 88.9%) followed by S. sonnei (ELISA: post-injection 1: 77.6%; post-injection 2: 84.6%; 78.8%; SBA: post-injection 1: 83.3%; post-injection 2: 71.4%; 88.9%). Immune responses against S. flexneri 1b and S. flexneri 3a, as measured by both ELISA and SBA, were numerically lower compared to those against S. sonnei and S. flexneri 2a. CONCLUSIONS: No safety signals or concerns were identified. altSonflex1-2-3 induced functional serotype-specific immune responses, allowing further clinical development in the target population.


What is the context? Shigella bacteria cause severe and often bloody diarrhea, called shigellosis, that affects mostly young children and can be life-threatening. Shigellosis is particularly common in low- and middle-income countries due to inadequate sanitation and limited access to healthcare. Since the immune response to Shigella is serotype-specific, an ideal vaccine should include multiple Shigella serotypes to ensure broad protection. What is new? We developed a novel vaccine against Shigella that includes Shigella sonnei and three prevalent Shigella flexneri serotypes. In Stage 1 (phase I) of the study, healthy European adults received two vaccine injections given 3 or 6 months apart. We found that: The vaccine was well tolerated, and no safety signals or concerns were identified.Regardless of the interval between injections, specific antibodies were elicited against all four Shigella serotypes, with highest levels against Shigella flexneri 2a and Shigella sonnei.Functional antibody levels peaked after the first injection, remaining higher than the baseline up to 6 months. A second injection did not boost responses but restored functional antibody levels to those after the first injection. What is the impact? The vaccine can now be tested in Stage 2 (phase II) of the study in Africa, a region highly affected by shigellosis.

2.
N Engl J Med ; 374(17): 1635-46, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-25629663

RESUMEN

BACKGROUND: The West African outbreak of Ebola virus disease that peaked in 2014 has caused more than 11,000 deaths. The development of an effective Ebola vaccine is a priority for control of a future outbreak. METHODS: In this phase 1 study, we administered a single dose of the chimpanzee adenovirus 3 (ChAd3) vaccine encoding the surface glycoprotein of Zaire ebolavirus (ZEBOV) to 60 healthy adult volunteers in Oxford, United Kingdom. The vaccine was administered in three dose levels--1×10(10) viral particles, 2.5×10(10) viral particles, and 5×10(10) viral particles--with 20 participants in each group. We then assessed the effect of adding a booster dose of a modified vaccinia Ankara (MVA) strain, encoding the same Ebola virus glycoprotein, in 30 of the 60 participants and evaluated a reduced prime-boost interval in another 16 participants. We also compared antibody responses to inactivated whole Ebola virus virions and neutralizing antibody activity with those observed in phase 1 studies of a recombinant vesicular stomatitis virus-based vaccine expressing a ZEBOV glycoprotein (rVSV-ZEBOV) to determine relative potency and assess durability. RESULTS: No safety concerns were identified at any of the dose levels studied. Four weeks after immunization with the ChAd3 vaccine, ZEBOV-specific antibody responses were similar to those induced by rVSV-ZEBOV vaccination, with a geometric mean titer of 752 and 921, respectively. ZEBOV neutralization activity was also similar with the two vaccines (geometric mean titer, 14.9 and 22.2, respectively). Boosting with the MVA vector increased virus-specific antibodies by a factor of 12 (geometric mean titer, 9007) and increased glycoprotein-specific CD8+ T cells by a factor of 5. Significant increases in neutralizing antibodies were seen after boosting in all 30 participants (geometric mean titer, 139; P<0.001). Virus-specific antibody responses in participants primed with ChAd3 remained positive 6 months after vaccination (geometric mean titer, 758) but were significantly higher in those who had received the MVA booster (geometric mean titer, 1750; P<0.001). CONCLUSIONS: The ChAd3 vaccine boosted with MVA elicited B-cell and T-cell immune responses to ZEBOV that were superior to those induced by the ChAd3 vaccine alone. (Funded by the Wellcome Trust and others; ClinicalTrials.gov number, NCT02240875.).


Asunto(s)
Vacunas contra el Virus del Ébola/inmunología , Ebolavirus/inmunología , Fiebre Hemorrágica Ebola/prevención & control , Adenovirus de los Simios/inmunología , Adulto , Animales , Anticuerpos Antivirales/sangre , Linfocitos B/fisiología , Citocinas/sangre , Vacunas contra el Virus del Ébola/administración & dosificación , Femenino , Fiebre Hemorrágica Ebola/inmunología , Humanos , Inmunidad Celular , Inmunización Secundaria , Masculino , Persona de Mediana Edad , Pan troglodytes , Linfocitos T/fisiología , Vaccinia , Adulto Joven
3.
J Neural Eng ; 21(1)2024 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-38266281

RESUMEN

Objective.Spatial auditory attention decoding (Sp-AAD) refers to the task of identifying the direction of the speaker to which a person is attending in a multi-talker setting, based on the listener's neural recordings, e.g. electroencephalography (EEG). The goal of this study is to thoroughly investigate potential biases when training such Sp-AAD decoders on EEG data, particularly eye-gaze biases and latent trial-dependent confounds, which may result in Sp-AAD models that decode eye-gaze or trial-specific fingerprints rather than spatial auditory attention.Approach.We designed a two-speaker audiovisual Sp-AAD protocol in which the spatial auditory and visual attention were enforced to be either congruent or incongruent, and we recorded EEG data from sixteen participants undergoing several trials recorded at distinct timepoints. We trained a simple linear model for Sp-AAD based on common spatial patterns filters in combination with either linear discriminant analysis (LDA) or k-means clustering, and evaluated them both across- and within-trial.Main results.We found that even a simple linear Sp-AAD model is susceptible to overfitting to confounding signal patterns such as eye-gaze and trial fingerprints (e.g. due to feature shifts across trials), resulting in artificially high decoding accuracies. Furthermore, we found that changes in the EEG signal statistics across trials deteriorate the trial generalization of the classifier, even when the latter is retrained on the test trial with an unsupervised algorithm.Significance.Collectively, our findings confirm that there exist subtle biases and confounds that can strongly interfere with the decoding of spatial auditory attention from EEG. It is expected that more complicated non-linear models based on deep neural networks, which are often used for Sp-AAD, are even more vulnerable to such biases. Future work should perform experiments and model evaluations that avoid and/or control for such biases in Sp-AAD tasks.


Asunto(s)
Percepción Auditiva , Percepción del Habla , Humanos , Estimulación Acústica/métodos , Electroencefalografía/métodos , Sesgo
4.
Drugs R D ; 24(1): 1-12, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38494581

RESUMEN

Superficial infections with Streptococcus pyogenes (Strep A), pharyngitis and impetigo can induce acute rheumatic fever, an autoimmune sequela manifesting mostly with arthritis and rheumatic carditis. Valvular heart damage can persist or advance following repeated episodes of acute rheumatic fever, causing rheumatic heart disease. Acute rheumatic fever and rheumatic heart disease disproportionately affect children and young adults in developing countries and disadvantaged communities in developed countries. People living with rheumatic heart disease are at risk of experiencing potentially fatal complications such as heart failure, bacterial endocarditis or stroke. Transthoracic echocardiography plays a central role in diagnosing both rheumatic carditis and rheumatic heart disease. Despite the obvious medical need, no licensed Strep A vaccines are currently available, as their clinical development process faces several challenges, including concerns for cardiac safety. However, the development of Strep A vaccines has been recently relaunched by many vaccine developers. In this context, a reliable and consistent safety evaluation of Strep A vaccine candidates, including the use of transthoracic echocardiography for detecting cardiac adverse events, could greatly contribute to developing a safe and efficacious product in the near future. Here, we propose a framework for the consistent use of transthoracic echocardiography to proactively detect cardiac safety events in clinical trials of Strep A vaccine candidates.


Throat and skin infections caused by certain types of bacteria, named Streptococcus pyogenes, are frequent worldwide; however, in many children from less developed countries and disadvantaged communities, infections with S. pyogenes lead to a condition called acute rheumatic fever, which usually affects the joints and the heart. Damage to the heart valves may evolve to rheumatic heart disease, a permanent condition with often life-threatening complications. Rheumatic heart disease is an important health problem in places and communities where S. pyogenes infections occur frequently. A vaccine against these bacteria would help lower the number of people with valvular heart disease; however, no such vaccine exists yet. Research on vaccines against S. pyogenes was on hold for almost 30 years because of initial concerns that vaccinated children might develop acute rheumatic fever more frequently. Recently, researchers started working again on vaccines against S. pyogenes, but concerns about the safety of such vaccines persist. Doctors can reliably use echocardiography to diagnose cases of rheumatic carditis (as a sign of acute rheumatic fever) and rheumatic heart disease. Here, we propose a simple approach for the consistent use of echocardiography in clinical research of vaccines against S. pyogenes that will allow the detection of any potential heart-related side effects of the vaccine.


Asunto(s)
Ecocardiografía , Infecciones Estreptocócicas , Vacunas Estreptocócicas , Streptococcus pyogenes , Humanos , Streptococcus pyogenes/inmunología , Ecocardiografía/métodos , Vacunas Estreptocócicas/administración & dosificación , Vacunas Estreptocócicas/efectos adversos , Vacunas Estreptocócicas/inmunología , Infecciones Estreptocócicas/prevención & control , Cardiopatía Reumática/diagnóstico por imagen
5.
J Sex Med ; 10(7): 1816-22, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23651241

RESUMEN

INTRODUCTION: Erectile dysfunction (ED) is more prevalent in men living with HIV (MLHIV) when compared with age-matched HIV-negative men. This may be related to a premature decline in testosterone levels. In the general population, ED has been associated with an increased risk for coronary heart disease (CHD). AIM: The aim of this study is to determine the prevalence of ED, testosterone deficiency, and risk of CHD in a cohort of young to middle-aged MLHIV in Belgium. METHODS: A cross-sectional, observational study among 244 MLHIV attending the outpatient clinic of the Institute of Tropical Medicine in Antwerp. MAIN OUTCOME MEASURES: The short version of the international index of erectile function (IIEF-5) questionnaire diagnosed ED (cutoff score ≤ 21). The 10-year risk score for CHD was calculated. In a subset of men reporting ED, the calculated free testosterone (CFT) was determined using Vermeulen's formula. Testosterone deficiency was defined as CFT <0.22 nmol/L. RESULTS: One hundred fifty-one men (61.9%) self-reported ED (median IIEF-5 score: 16 [interquartile range (IQR) 12-19]). In multivariate analysis, only increasing age, but none of the HIV-related parameters, nor any of the individual cardiovascular-risk related parameters, was statistically significantly associated with ED. Eighteen out of the 49 (36.7%) men with ED who received a blood test to assess testosterone levels were diagnosed with testosterone deficiency. The 10-year risk of CHD in the cohort was 4.3% (IQR 3.6-5.7) and was significantly higher in men with ED (5.1%, IQR 4.4-6.6) compared with men without ED (3.1%, IQR 2.5-4.2). CONCLUSIONS: This study showed that ED and testosterone deficiency are highly prevalent in young to middle-aged MLHIV and that ED might be associated with an increased risk of CHD. Therefore, healthcare professionals should screen for clinical ED and should consider testing for underlying testosterone deficiency. A clinical diagnosis of ED should trigger a full evaluation of the patient's cardiovascular risk factors, even at younger age.


Asunto(s)
Enfermedad de la Arteria Coronaria/epidemiología , Disfunción Eréctil/epidemiología , Infecciones por VIH/epidemiología , Testosterona/deficiencia , Adulto , Bélgica/epidemiología , Estudios Transversales , Disfunción Eréctil/sangre , Seropositividad para VIH/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Testosterona/sangre
6.
AIDS Care ; 25(8): 1062-6, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23244618

RESUMEN

Studies have shown more erectile dysfunction (ED) in men living with HIV (MLHIV), relative to age matched HIV-negative men. Erection enhancing medication (EEM) is more frequently used by HIV-positive men than in the general male population. Increased sexually transmitted infection has been described in HIV-positive men with ED using EEM. This study investigated the use of EEM and party drugs (methyleendioxymethamfetamine (XTC), gammahydroxybutyrate (GHB) "fluid XTC" and alkyl nitrites "poppers") among MLHIV. Self-administered questionnaires were distributed consecutively to all patients attending 17 European HIV treatment centers. The sample included 1118 HIV-positive men, among whom 74.5% men having sex with men (MSM). The use of EEM was more frequent in MSM than in heterosexual men (odds ratio (OR) 3.33, p<0.001) and was associated with increased sexual risk behavior (OR 3.27, p<0.001). Nonmedically indicated use of EEM was linked to increased use of party drugs (OR 2.30, p=0.01). Physicians taking care of MLHIV need to be aware of the high prevalence of (nonmedical) use of EEM and party drugs. Medical provision of EEM should be combined with a discussion on safer sex behavior and the risk related to concomitant use of party drugs and illegal EEM.


Asunto(s)
Disfunción Eréctil/tratamiento farmacológico , Infecciones por VIH/epidemiología , Drogas Ilícitas , N-Metil-3,4-metilenodioxianfetamina , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Conducta Sexual/estadística & datos numéricos , Estudios de Cohortes , Estudios Transversales , Europa (Continente) , Humanos , Masculino , Oportunidad Relativa , Estudios Retrospectivos , Asunción de Riesgos , Encuestas y Cuestionarios , Sexo Inseguro/estadística & datos numéricos
7.
Drugs R D ; 22(1): 1-8, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34921644

RESUMEN

Hematological and clinical chemistry measurements are an integral part of vaccine safety monitoring. While adopting a conservative approach is important to exclude potential risks for patients, the rationale and methodology underlying the assessment of given adverse events have to be well grounded to avoid raising unfounded concerns. Using asymptomatic transient neutropenia as an example, this paper aims to address the complexity of interpreting abnormal hematological values in vaccine clinical trials and to evaluate the validity of using neutrophil count cut-off points to assess neutropenia in the context of safety monitoring. The validity of the neutrophil count cut-off point methodology was assessed in terms of content validity (i.e., the extent to which a single neutrophil count below the cut-off point corresponds to a clinically significant adverse event), criterion validity (i.e., the extent to which a neutrophil count below a given cut-off point correlates with another manifestation of neutropenia, namely bacteremia), and construct validity (i.e., the exactness of the assumption that a neutrophil count below a given cut-off point corresponds to a reactogenic event caused by the vaccination). We argue that, because of within-individual physiological fluctuations, variations according to population demographics, and poor predictive potential with regard to neutropenia-associated infection, the application of the cut-off point methodology to neutropenia safety monitoring presents major limitations. Based on this assessment, we conclude that hematological laboratory values must be evaluated on a case-by-case basis by investigators to determine their clinical significance.


Asunto(s)
Neutropenia , Vacunas , Humanos , Laboratorios , Neutropenia/inducido químicamente , Neutropenia/complicaciones , Neutrófilos , Vacunas/efectos adversos
8.
Infect Dis Ther ; 11(2): 757-770, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35118580

RESUMEN

INTRODUCTION: Shigellosis is a major health concern among children < 5 years of age from developing countries, and there are no widely available vaccines to prevent it. The GMMA-based 1790GAHB investigational vaccine against Shigella sonnei was well tolerated and immunogenic in phase 1 and 2 studies conducted in healthy adults from Shigella endemic and non-endemic populations. Based on pooled data of five individual trials, we assessed the association between vaccine administration and the risk of neutropenia as well as the overall safety profile of 1790GAHB. METHODS: The risk ratio (RR) of neutropenia was evaluated between participants receiving 1790GAHB (vaccinees) and active comparator/placebo (controls) using different ethnicity-specific absolute neutrophil count (ANC) thresholds established to define neutropenia. Safety was assessed in terms of solicited, unsolicited, and serious adverse events (AEs). RESULTS: Of the 279 participants, 11 (5.5%) vaccinees and 4 (5.0%) controls had ANC below the appropriate threshold within 7 days post-vaccination. RR was 0.96 [95% confidence interval (CI) 0.54-1.70]. When neutrophil counts of participants of African descent were measured against an ethnicity non-specific threshold, they resulted in neutropenia episodes in 30 (37.0%) vaccinees and 16 (30.2%) controls, while only 2 (2.5%) vaccinees and 1 (1.9%) control had neutropenia when the ethnicity-specific threshold was applied. RRs were 0.98 (95% CI 0.75-1.28) and 1.30 (95% CI 0.1-17.6), respectively. Solicited and unsolicited AEs were slightly more frequent among vaccinees than controls. No serious AEs, other than neutropenia cases, were recorded in the vaccine group. CONCLUSION: By applying the appropriate threshold, no increased risk of neutropenia was identified in vaccinees compared with the controls. The frequency of neutropenia events varied drastically when ethnicity-appropriate thresholds were applied. This observation highlights the importance of selecting appropriate cut-off values according to the correct population reference. Overall, the 1790GAHB vaccine demonstrated an acceptable safety profile.

9.
EClinicalMedicine ; 39: 101076, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34430837

RESUMEN

BACKGROUND: Shigellosis accounts for substantial morbidity and mortality worldwide and is the second most common cause of moderate and severe diarrhoea in children. METHODS: This phase 2b study (NCT03527173), conducted between August 2018 and November 2019, evaluated vaccine efficacy (VE), safety, and immunogenicity of a Shigella sonnei GMMA candidate vaccine (1790GAHB) in adults, using a S. sonnei 53 G controlled human infection model. Participants (randomized 1:1) received two doses of 1790GAHB or placebo (GAHB-Placebo), at day (D) 1 and D29, and an oral challenge of S. sonnei 53 G at D57. VE was evaluated using several endpoints, reflecting different case definitions of shigellosis. For the primary endpoint, the success criterion was a lower limit of the 90% confidence interval >0. FINDINGS: Thirty-six and 35 participants received 1790GAHB or placebo, respectively; 33 and 29 were challenged, 15 and 12 developed shigellosis. VE was not demonstrated for any endpoint. Adverse events were more frequent in 1790GAHB versus placebo recipients post-vaccination. Anti-S. sonnei lipopolysaccharide (LPS) IgG responses increased at D29 and remained stable through D57 in group 1790GAHB; no increase was shown in placebo recipients. INTERPRETATION: 1790GAHB had an acceptable safety profile and induced anti-LPS IgG responses but did not demonstrate clinical efficacy against shigellosis. Baseline/pre-challenge antibody levels were higher in participants who did not develop shigellosis post-challenge, suggesting a role of anti-LPS IgG antibodies in clinical protection, although not fully elucidated in this study. For further vaccine development an increased S. sonnei O-antigen content is likely needed to enhance anti-LPS immune responses. FUNDING: GlaxoSmithKline Biologicals SA, Bill and Melinda Gates Foundation.

10.
J Patient Saf ; 16(4): e292-e298, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32897039

RESUMEN

OBJECTIVE: The aim of the study was to design an objective, transparent, pragmatic, and flexible workflow to assist with patient selection during the initial phase of return to elective orthopedic surgery during the COVID-19 pandemic with the main purpose of enhancing patient safety. METHODS: A multidisciplinary working group was formed consisting of representatives for orthopedics, epidemiology, ethics, infectious diseases, cardiovascular diseases, and intensive care medicine. Preparation for upcoming meetings consisted of reading up on literature and testing of proposed methodologies on our own waiting lists. RESULTS: A workflow based on 3 domains, that is, required resources, patient fitness, and time sensitivity of the procedure, was considered most useful. All domains function as standalones, in a specific order, and no sum score is used. The domain of required resources demands input from the surgical team, results in a categorical (yes or no) outcome, and generates a list of potential patients who can be scheduled for surgery under these particular circumstances. The (weighted) items for the domain of patient fitness are the same for every patient, are scored on a numerical scale, but are likely to change during the pandemic as more data become available. Time sensitivity of the procedure is again scored on a numerical scale and becomes increasingly important when returning to elective surgery proves to be acceptably safe. After patient selection, an augmented informed consent, screening, and testing according to local guidelines will take place. CONCLUSIONS: A workflow is proposed for patient selection aiming for the safest possible return to elective orthopedic surgery during the COVID-19 pandemic.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Procedimientos Quirúrgicos Electivos/métodos , Procedimientos Ortopédicos/métodos , Selección de Paciente , Neumonía Viral/epidemiología , Betacoronavirus/aislamiento & purificación , COVID-19 , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/prevención & control , Humanos , Comunicación Interdisciplinaria , Pandemias/prevención & control , Neumonía Viral/diagnóstico , Neumonía Viral/prevención & control , SARS-CoV-2
11.
Lancet Infect Dis ; 20(6): 719-730, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32199492

RESUMEN

BACKGROUND: During the large 2013-16 Ebola virus outbreak caused by the Zaire Ebola virus, about 20% of cases were reported in children. This study is the first, to our knowledge, to evaluate an Ebola vaccine in children younger than 6 years. We aimed to evaluate the safety, reactogenicity, and immunogenicity of a monovalent, recombinant, chimpanzee adenovirus type-3 vectored Zaire Ebola glycoprotein vaccine (ChAd3-EBO-Z) in a paediatric population. METHODS: This phase 2, randomised, observer-blind, controlled trial was done in a vaccine centre in Mali and a university hospital centre in Senegal. Healthy children were randomly assigned through a web-based system (1:1; stratified by age group, gender, and centre) to receive ChAd3-EBO-Z (day 0) and meningococcal serogroups A,C,W-135,Y tetanus toxoid conjugate vaccine (MenACWY-TT; month 6), or MenACWY-TT (day 0) and ChAd3-EBO-Z (month 6). The study was observer-blind from study start until interim day 30 analysis and became single-blind as of interim analysis. Primary outcomes assessed were serious adverse events (up to study end, month 12), solicited local or general adverse events (7 days post-vaccination), unsolicited adverse events (30 days post-vaccination), haematological or biochemical abnormalities, and clinical symptoms of thrombocytopenia (day 0-6). As secondary endpoints, we evaluated anti-glycoprotein Zaire Ebola virus antibody titres (ELISA) pre-vaccination and 30 days post-vaccination. This study is registered with ClinicalTrials.gov, NCT02548078. FINDINGS: From Nov 11, 2015, to May 9, 2016, of 776 children screened for eligibility, 600 were randomly assigned (200 [33%] in each age strata: 1-5, 6-12, 13-17 years), 300 (50%) to the ChAd3-EBO-Z/MenACWY-TT group and 300 (50%) to the MenACWY-TT/ChAd3-EBO-Z group; all were included in the total vaccinated cohort. Post-day 0 vaccination, the most common solicited injection site symptom was pain (127 [42%] of 300 in the ChAd3-EBO-Z/MenACWY-TT group vs 60 [20%] of 300 in the MenACWY-TT/ChAd3-EBO-Z group); the most common solicited general adverse event was fever (95 [32%] of 300 in the ChAd3-EBO-Z/MenACWY-TT group vs 28 [9%] of 300 in the MenACWY-TT/ChAd3-EBO-Z group). Unsolicited adverse events post-day 0 vaccination were reported by 41 (14%) of 300 participants in the ChAd3-EBO-Z/MenACWY-TT group and 24 (8%) of 300 MenACWY-TT/ChAd3-EBO-Z recipients. Serious adverse events were reported for two (1%) of 300 children in each group; none were considered vaccination related. No clinical symptoms of thrombocytopenia were reported. At day 30, anti-glycoprotein Ebola virus antibody geometric mean concentrations (GMC) in the ChAd3-EBO-Z/MenACWY-TT group were 1564 (95% CI 1340-1826) for those aged 13-17 years, 1395 (1175-1655) for 6-12 years, and 2406 (1942-2979) for 1-5 years. Anti-glycoprotein Ebola virus IgG antibody responses persisted up to 12 months post-vaccination, with a GMC of 716 (95% CI 619-828) for those aged 13-17 years, 752 (645-876) for 6-12 years, and 1424 (1119-1814) for 1-5 years. INTERPRETATION: ChAd3-EBO-Z was immunogenic and well tolerated in children aged 1-17 years. This study provides the first ChAd3-EBO-Z data in a paediatric population. Further development should focus on multivalent approaches including Sudan and Marburg strains, and heterologous prime-boost strategies, for instance using modified vaccinia Ankara-based vaccine to boost the immune response. FUNDING: EU's Horizon 2020 research and innovation programme and GlaxoSmithKline Biologicals SA.


Asunto(s)
Adenovirus de los Simios , Vacunas contra el Virus del Ébola/efectos adversos , Vacunas contra el Virus del Ébola/inmunología , Fiebre Hemorrágica Ebola/prevención & control , Adolescente , Animales , Anticuerpos Antivirales/sangre , Niño , Preescolar , Femenino , Vectores Genéticos , Humanos , Lactante , Masculino , Pan troglodytes , Método Simple Ciego , Vacunas Sintéticas/inmunología
12.
Lancet Infect Dis ; 20(6): 707-718, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32199491

RESUMEN

BACKGROUND: The 2014 Zaire Ebola virus disease epidemic accelerated vaccine development for the virus. We aimed to assess the safety, reactogenicity, and immunogenicity of one dose of monovalent, recombinant, chimpanzee adenovirus type-3 vectored Zaire Ebola glycoprotein vaccine (ChAd3-EBO-Z) in adults. METHODS: This phase 2, randomised, observer-blind, controlled trial was done in study centres in Cameroon, Mali, Nigeria, and Senegal. Healthy adults (≥18 years) were randomly assigned with a web-based system (1:1; minimisation procedure accounting for age, gender, centre) to receive ChAd3-EBO-Z (day 0), or saline placebo (day 0) and ChAd3-EBO-Z (month 6). The study was observer-blind until planned interim day 30 analysis, single-blind until month 6, and open-label after month 6 vaccination. Primary outcomes assessed in the total vaccinated cohort, which comprised all participants with at least one study dose administration documented, were serious adverse events (up to study end, month 12); and for a subcohort were solicited local or general adverse events (7 days post-vaccination), unsolicited adverse events (30 days post-vaccination), haematological or biochemical abnormalities, and clinical symptoms of thrombocytopenia (day 0-6). Secondary endpoints (subcohort; per-protocol cohort) evaluated anti-glycoprotein Ebola virus antibody titres (ELISA) pre-vaccination and 30 days post-vaccination. This study is registered with ClinicalTrials.gov, NCT02485301. FINDINGS: Between July 22, 2015, and Dec 10, 2015, 3030 adults were randomly assigned; 3013 were included in the total vaccinated cohort (1509 [50·1%] in the ChAd3-EBO-Z group and 1504 [49·9%] in the placebo/ChAd3-EBO-Z group), 17 were excluded because no vaccine was administered. The most common solicited injection site symptom was pain (356 [48%] of 748 in the ChAd3-EBO-Z group vs 57 [8%] of 751 in the placebo/ChAd3-EBO-Z group); the most common solicited general adverse event was headache (345 [46%] in the ChAd3-EBO-Z group vs 136 [18%] in the placebo/ChAd3-EBO-Z group). Unsolicited adverse events were reported by 123 (16%) of 749 in the ChAd3-EBO-Z group and 119 (16%) of 751 in the placebo/ChAd3-EBO-Z group. Serious adverse events were reported for 11 (1%) of 1509 adults in the ChAd3-EBO-Z group, and 18 (1%) of 1504 in the placebo/ChAd3-EBO-Z group; none were considered vaccination-related. No clinically meaningful thrombocytopenia was reported. At day 30, anti-glycoprotein Ebola virus antibody geometric mean concentration was 900 (95% CI 824-983) in the ChAd3-EBO-Z group. There were no treatment-related deaths. INTERPRETATION: ChAd3-EBO-Z was immunogenic and well tolerated in adults. Our findings provide a strong basis for future development steps, which should concentrate on multivalent approaches (including Sudan and Marburg strains). Additionally, prime-boost approaches should be a focus with a ChAd3-based vaccine for priming and boosted by a modified vaccinia Ankara-based vaccine. FUNDING: EU's Horizon 2020 research and innovation programme and GlaxoSmithKline Biologicals SA.


Asunto(s)
Adenovirus de los Simios , Vacunas contra el Virus del Ébola/efectos adversos , Vacunas contra el Virus del Ébola/inmunología , Fiebre Hemorrágica Ebola/prevención & control , Adolescente , Adulto , Animales , Anticuerpos Antivirales/sangre , Femenino , Vectores Genéticos , Humanos , Masculino , Persona de Mediana Edad , Pan troglodytes , Método Simple Ciego , Vacunas Sintéticas/inmunología
13.
Vaccine ; 37(23): 3113-3122, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31029515

RESUMEN

Non-typeable Haemophilus influenzae (NTHi) and Moraxella catarrhalis (Mcat) are frequent pathogens in acute exacerbations of COPD. We assessed the safety, reactogenicity and immunogenicity of different investigational vaccine formulations containing surface proteins of NTHi (PD and PE-PilA) and Mcat (UspA2) in adults with smoking history ≥10 pack-years, to immunologically represent the COPD population. Participants received two doses 60 days apart in a randomised, observer-blind, placebo-controlled study (NCT02547974). In step 1, 30 healthy adults aged 18-40 years were randomised (1:1) to receive a non-adjuvanted formulation (10-10-PLAIN) or placebo. In step 2, 90 smokers/ex-smokers aged 50-70 years randomly (1:1:1) received an AS01-adjuvanted formulation containing either 10 µg of each antigen (10-10-AS01) or 10 µg of each NTHi antigen and 3.3 µg of Mcat antigen (10-3-AS01), or placebo. Incidences of solicited local adverse events (AEs) tended to be highest in the AS01-adjuvanted vaccine groups. Most solicited AEs had mild/moderate intensity. No vaccine-related serious AEs were reported. The 10-3-AS01 formulation induced the best humoral immune response against the NTHi antigens. Responses against the Mcat antigen were similar across groups, with waning immunogenicity after 30 days post-dose 2. The investigational NTHi-Mcat vaccine had an acceptable safety and reactogenicity profile and good immunogenicity in older adults with a smoking history.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Vacunas Bacterianas/inmunología , Esquemas de Inmunización , Inmunogenicidad Vacunal , Enfermedad Pulmonar Obstructiva Crónica/prevención & control , Adyuvantes Inmunológicos/administración & dosificación , Adulto , Anciano , Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/administración & dosificación , Vacunas Bacterianas/efectos adversos , Método Doble Ciego , Femenino , Haemophilus influenzae , Humanos , Inmunidad Humoral , Masculino , Persona de Mediana Edad , Moraxella catarrhalis , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Fumadores , Adulto Joven
14.
Vaccine ; 37(41): 6102-6111, 2019 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-31447126

RESUMEN

Loss of airway microbial diversity is associated with non-typeable Haemophilus influenzae (NTHi) infection and increased risk of exacerbation in chronic obstructive pulmonary disease (COPD). We assessed the safety and immunogenicity of an investigational vaccine containing NTHi antigens, recombinant protein D (PD) and combined protein E and Pilin A (PE-PilA), and AS01 adjuvant in adults with moderate/severe COPD and prior exacerbations. In this phase 2, observer-blind, controlled trial (NCT02075541), 145 COPD patients aged 40-80 years randomly (1:1) received two doses of NTHi vaccine or placebo 60 days apart, on top of standard care. Reactogenicity in the 7-day post-vaccination period was higher following NTHi vaccine than placebo. Most solicited adverse events (AEs) were mild/moderate. At least one unsolicited AE was reported during the 30-day post-vaccination period by 54.8% of NTHi vaccine and 51.4% of placebo recipients. One serious AE (placebo group) was assessed by the investigator as vaccine-related. Anti-PD, anti-PE and anti-PilA geometric mean antibody concentrations increased up to 30 days after each NTHi vaccine dose, waned thereafter, but remained higher than baseline (non-overlapping confidence intervals) up to 13 months post-dose 2. The frequency of specific CD4+ T cells increased following two doses of NTHi vaccine and remained higher than baseline. Exploratory analysis showed a statistically non-significant lower yearly rate of moderate/severe exacerbations in the NTHi vaccine group than following placebo (1.49 versus 1.73) in the one-year period post-dose 2, with estimated vaccine efficacy of 13.3% (95% confidence interval -24.2 to 39.5; p = 0.44). The NTHi vaccine had an acceptable safety and reactogenicity profile and good immunogenicity in adults with COPD.


Asunto(s)
Vacunas contra Haemophilus/inmunología , Vacunas contra Haemophilus/uso terapéutico , Haemophilus influenzae/inmunología , Haemophilus influenzae/patogenicidad , Enfermedad Pulmonar Obstructiva Crónica/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunidad Celular/inmunología , Inmunidad Humoral/inmunología , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/inmunología
17.
Lancet Infect Dis ; 16(3): 311-20, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26725450

RESUMEN

BACKGROUND: The ongoing Ebola outbreak led to accelerated efforts to test vaccine candidates. On the basis of a request by WHO, we aimed to assess the safety and immunogenicity of the monovalent, recombinant, chimpanzee adenovirus type-3 vector-based Ebola Zaire vaccine (ChAd3-EBO-Z). METHODS: We did this randomised, double-blind, placebo-controlled, dose-finding, phase 1/2a trial at the Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. Participants (aged 18-65 years) were randomly assigned (2:2:1), via two computer-generated randomisation lists for individuals potentially deployed in endemic areas and those not deployed, to receive a single intramuscular dose of high-dose vaccine (5 × 10(10) viral particles), low-dose vaccine (2·5 × 10(10) viral particles), or placebo. Deployed participants were allocated to only the vaccine groups. Group allocation was concealed from non-deployed participants, investigators, and outcome assessors. The safety evaluation was not masked for potentially deployed participants, who were therefore not included in the safety analysis for comparison between the vaccine doses and placebo, but were pooled with the non-deployed group to compare immunogenicity. The main objectives were safety and immunogenicity of ChAd3-EBO-Z. We did analysis by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT02289027. FINDINGS: Between Oct 24, 2014, and June 22, 2015, we randomly assigned 120 participants, of whom 18 (15%) were potentially deployed and 102 (85%) were non-deployed, to receive high-dose vaccine (n=49), low-dose vaccine (n=51), or placebo (n=20). Participants were followed up for 6 months. No vaccine-related serious adverse events were reported. We recorded local adverse events in 30 (75%) of 40 participants in the high-dose group, 33 (79%) of 42 participants in the low-dose group, and five (25%) of 20 participants in the placebo group. Fatigue or malaise was the most common systemic adverse event, reported in 25 (62%) participants in the high-dose group, 25 (60%) participants in the low-dose group, and five (25%) participants in the placebo group, followed by headache, reported in 23 (57%), 25 (60%), and three (15%) participants, respectively. Fever occurred 24 h after injection in 12 (30%) participants in the high-dose group and 11 (26%) participants in the low-dose group versus one (5%) participant in the placebo group. Geometric mean concentrations of IgG antibodies against Ebola glycoprotein peaked on day 28 at 51 µg/mL (95% CI 41·1-63·3) in the high-dose group, 44·9 µg/mL (25·8-56·3) in the low-dose group, and 5·2 µg/mL (3·5-7·6) in the placebo group, with respective response rates of 96% (95% CI 85·7-99·5), 96% (86·5-99·5), and 5% (0·1-24·9). Geometric mean concentrations decreased by day 180 to 25·5 µg/mL (95% CI 20·6-31·5) in the high-dose group, 22·1 µg/mL (19·3-28·6) in the low-dose group, and 3·2 µg/mL (2·4-4·9) in the placebo group. 28 (57%) participants given high-dose vaccine and 31 (61%) participants given low-dose vaccine developed glycoprotein-specific CD4 cell responses, and 33 (67%) and 35 (69%), respectively, developed CD8 responses. INTERPRETATION: ChAd3-EBO-Z was safe and well tolerated, although mild to moderate systemic adverse events were common. A single dose was immunogenic in almost all vaccine recipients. Antibody responses were still significantly present at 6 months. There was no significant difference between doses for safety and immunogenicity outcomes. This acceptable safety profile provides a reliable basis to proceed with phase 2 and phase 3 efficacy trials in Africa. FUNDING: Swiss State Secretariat for Education, Research and Innovation (SERI), through the EU Horizon 2020 Research and Innovation Programme.


Asunto(s)
Adenoviridae/clasificación , Anticuerpos Antivirales/sangre , Vacunas contra el Virus del Ébola/inmunología , Fiebre Hemorrágica Ebola/prevención & control , Adulto , Relación Dosis-Respuesta Inmunológica , Vacunas contra el Virus del Ébola/administración & dosificación , Vacunas contra el Virus del Ébola/efectos adversos , Ebolavirus/inmunología , Femenino , Fiebre/inducido químicamente , Fiebre Hemorrágica Ebola/virología , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Personal Militar , Vacunas de ADN/inmunología , Adulto Joven
18.
Lancet Infect Dis ; 16(1): 31-42, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26546548

RESUMEN

BACKGROUND: The 2014 west African Zaire Ebola virus epidemic prompted worldwide partners to accelerate clinical development of replication-defective chimpanzee adenovirus 3 vector vaccine expressing Zaire Ebola virus glycoprotein (ChAd3-EBO-Z). We aimed to investigate the safety, tolerability, and immunogenicity of ChAd3-EBO-Z in Malian and US adults, and assess the effect of boosting of Malians with modified vaccinia Ankara expressing Zaire Ebola virus glycoprotein and other filovirus antigens (MVA-BN-Filo). METHODS: In the phase 1, single-blind, randomised trial of ChAd3-EBO-Z in the USA, we recruited adults aged 18-65 years from the University of Maryland medical community and the Baltimore community. In the phase 1b, open-label and double-blind, dose-escalation trial of ChAd3-EBO-Z in Mali, we recruited adults 18-50 years of age from six hospitals and health centres in Bamako (Mali), some of whom were also eligible for a nested, randomised, double-blind, placebo-controlled trial of MVA-BN-Filo. For randomised segments of the Malian trial and for the US trial, we randomly allocated participants (1:1; block size of six [Malian] or four [US]; ARB produced computer-generated randomisation lists; clinical staff did randomisation) to different single doses of intramuscular immunisation with ChAd3-EBO-Z: Malians received 1 × 10(10) viral particle units (pu), 2·5 × 10(10) pu, 5 × 10(10) pu, or 1 × 10(11) pu; US participants received 1 × 10(10) pu or 1 × 10(11) pu. We randomly allocated Malians in the nested trial (1:1) to receive a single dose of 2 × 10(8) plaque-forming units of MVA-BN-Filo or saline placebo. In the double-blind segments of the Malian trial, investigators, clinical staff, participants, and immunology laboratory staff were masked, but the study pharmacist (MK), vaccine administrator, and study statistician (ARB) were unmasked. In the US trial, investigators were not masked, but participants were. Analyses were per protocol. The primary outcome was safety, measured with occurrence of adverse events for 7 days after vaccination. Both trials are registered with ClinicalTrials.gov, numbers NCT02231866 (US) and NCT02267109 (Malian). FINDINGS: Between Oct 8, 2014, and Feb 16, 2015, we randomly allocated 91 participants in Mali (ten [11%] to 1 × 10(10) pu, 35 [38%] to 2·5 × 10(10) pu, 35 [38%] to 5 × 10(10) pu, and 11 [12%] to 1 × 10(11) pu) and 20 in the USA (ten [50%] to 1 × 10(10) pu and ten [50%] to 1 × 10(11) pu), and boosted 52 Malians with MVA-BN-Filo (27 [52%]) or saline (25 [48%]). We identified no safety concerns with either vaccine: seven (8%) of 91 participants in Mali (five [5%] received 5 × 10(10) and two [2%] received 1 × 10(11) pu) and four (20%) of 20 in the USA (all received 1 × 10(11) pu) given ChAd3-EBO-Z had fever lasting for less than 24 h, and 15 (56%) of 27 Malians boosted with MVA-BN-Filo had injection-site pain or tenderness. INTERPRETATION: 1 × 10(11) pu single-dose ChAd3-EBO-Z could suffice for phase 3 efficacy trials of ring-vaccination containment needing short-term, high-level protection to interrupt transmission. MVA-BN-Filo boosting, although a complex regimen, could confer long-lived protection if needed (eg, for health-care workers). FUNDING: Wellcome Trust, Medical Research Council UK, Department for International Development UK, National Cancer Institute, Frederick National Laboratory for Cancer Research, Federal Funds from National Institute of Allergy and Infectious Diseases.


Asunto(s)
Vacunas contra el Virus del Ébola/administración & dosificación , Fiebre Hemorrágica Ebola/prevención & control , Inmunización Secundaria , Adolescente , Adulto , Anciano , Animales , Antígenos Virales/inmunología , Relación Dosis-Respuesta Inmunológica , Método Doble Ciego , Femenino , Glicoproteínas/inmunología , Fiebre Hemorrágica Ebola/inmunología , Fiebre Hemorrágica Ebola/virología , Humanos , Masculino , Malí , Persona de Mediana Edad , Método Simple Ciego , Estados Unidos , Adulto Joven
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