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Behavioral neurology & neuropsychiatry (BNNP) fellowships are accredited by the United Council for Neurologic Subspecialties (UCNS). Programs cover the UCNS-recommended topics differently. A curriculum accessible to all fellowships would standardize education and identify gaps in topics that are less well covered across programs. The purpose of the present needs assessment was to inform the development of the Online Core Curriculum and Mastery: BNNP (OCCAM-BNNP), a website for all UCNS-accredited BNNP programs. Program directors and fellows were surveyed to learn how well topics are covered and identify educational gaps, or specific topics on the UCNS website that are less well represented among programs. Thirty-seven fellowship program directors listed on the UCNS website were invited to take the survey and forward it to both current fellows (graduating in 2021) and recent graduates (graduated from 2015 to 2020). There were 29 responses from 37 programs. Of the 34 topics that respondents rated on a 1-5 Likert scale (from "not covered" to "completely covered"), 15 of 34 (44%) were identified as having >40% of responses as mostly "not covered," "incompletely covered," or "partially covered." Ninety-seven percent of respondents affirmed that it would be useful to have a free web-based resource for BNNP education. Slightly under one-half of all BNNP topics were not well covered. A survey was undertaken to identify and fill the educational gaps indicated by fellowship directors and fellows, and the OCCAM-BNNP website was developed as a repository for relevant content, providing a resource that many BNNP clinicians would find useful.
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Neurologia , Neuropsiquiatria , Humanos , Estados Unidos , Avaliação das Necessidades , Currículo , Bolsas de Estudo , Neurologia/educação , Inquéritos e QuestionáriosRESUMO
Dysexecutive Alzheimer's disease (dAD) manifests as a progressive dysexecutive syndrome without prominent behavioral features, and previous studies suggest clinico-radiological heterogeneity within this syndrome. We uncovered this heterogeneity using unsupervised machine learning in 52 dAD patients with multimodal imaging and cognitive data. A spectral decomposition of covariance between FDG-PET images yielded six latent factors ("eigenbrains") accounting for 48% of variance in patterns of hypometabolism. These eigenbrains differentially related to age at onset, clinical severity, and cognitive performance. A hierarchical clustering on the eigenvalues of these eigenbrains yielded four dAD subtypes, i.e. "left-dominant," "right-dominant," "bi-parietal-dominant," and "heteromodal-diffuse." Patterns of FDG-PET hypometabolism overlapped with those of tau-PET distribution and MRI neurodegeneration for each subtype, whereas patterns of amyloid deposition were similar across subtypes. Subtypes differed in age at onset and clinical severity where the heteromodal-diffuse exhibited a worse clinical picture, and the bi-parietal had a milder clinical presentation. We propose a conceptual framework of executive components based on the clinico-radiological associations observed in dAD. We demonstrate that patients with dAD, despite sharing core clinical features, are diagnosed with variability in their clinical and neuroimaging profiles. Our findings support the use of data-driven approaches to delineate brain-behavior relationships relevant to clinical practice and disease physiology.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Fluordesoxiglucose F18 , Encéfalo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Neuroimagem , Imageamento por Ressonância MagnéticaRESUMO
INTRODUCTION: Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers are promising tools to help identify the underlying pathology of neurocognitive disorders. In this manuscript, we report our experience with AD CSF biomarkers in 262 consecutive patients in a tertiary care memory clinic. METHODS: We retrospectively reviewed 262 consecutive patients who underwent lumbar puncture (LP) and CSF measurement of AD biomarkers (Aß1-42, total tau or t-tau, and p-tau181). We studied the safety of the procedure and its impact on patient's diagnosis and management. RESULTS: The LP allowed to identify underlying AD pathology in 72 of the 121 patients (59%) with early onset amnestic mild cognitive impairment (aMCI) with a high probability of progression to AD; to distinguish the behavioral/dysexecutive variant of AD from the behavioral variant of frontotemporal dementia (bvFTD) in 25 of the 45 patients (55%) with an atypical neurobehavioral profile; to identify AD as the underlying pathology in 15 of the 27 patients (55%) with atypical or unclassifiable primary progressive aphasia (PPA); and to distinguish AD from other disorders in 9 of the 29 patients (31%) with psychiatric differential diagnoses and 19 of the 40 patients (47%) with lesional differential diagnoses (normal pressure hydrocephalus, encephalitis, prion disease, etc.). No major complications occurred following the LP. INTERPRETATION: Our results suggest that CSF analysis is a safe and effective diagnostic tool in select patients with neurocognitive disorders. We advocate for a wider use of this biomarker in tertiary care memory clinics in Canada.
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Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico , Humanos , Fragmentos de Peptídeos/líquido cefalorraquidiano , Estudos Retrospectivos , Atenção Terciária à Saúde , Proteínas tau/líquido cefalorraquidianoRESUMO
PURPOSE: We aimed to investigate: (1) the clinical, diagnostic value of a written discourse task, and (2) the relationship between executive functions and written discourse within the spectrum of individuals with mild cognitive impairment (MCI). METHOD: To determine whether written discourse performance predicts clinical course among individuals with MCI, we retrospectively classified individuals with MCI as converters (N = 26) who were later diagnosed with dementia or as a stable MCI group (N = 45). We quantified core word measures from written discourse samples obtained from the Cookie Theft picture description task. RESULT: Written discourse measures differentiated converters from the stable MCI group. Converters produced a fewer number of core words than the stable MCI group. A measure of executive function significantly predicted performance on the production of core words in written discourse for the converters. In a multivariable regression, production of core words remained the only explanatory variable closely associated with the progression to dementia in MCI. CONCLUSION: Written discourse tasks can predict the likelihood of MCI progressing to dementia, independently of recall and an executive function measure. Correlational results suggest that written discourse performance was associated with executive function as measured by the Trail Making Test. Our findings emphasize the usefulness of including written discourse tasks in language assessment batteries targeting preclinical dementia populations.
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Disfunção Cognitiva , Demência , Redação , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Demência/diagnóstico , Demência/psicologia , Progressão da Doença , Função Executiva , Humanos , Idioma , Testes Neuropsicológicos , Estudos RetrospectivosRESUMO
A patient diagnosed with developmental delay, intellectual disability, and autistic and obsessive-compulsive symptoms was found to have a posterior fossa arachnoid cyst (PFAC) compressing the cerebellum. The patient was referred to our Ataxia Unit for consideration of surgical drainage of the cyst to improve his clinical constellation. This scenario led to an in-depth analysis including a literature review, functional resting-state MRI analysis of our patient compared to a group of controls, and genetic testing. While it is reasonable to consider that there may be a causal relationship between PFAC and neurodevelopmental or psychiatric symptoms in some patients, there is also a nontrivial prevalence of PFAC in the asymptomatic population and a significant possibility that many PFAC are incidental findings in the context of primary cognitive or psychiatric symptoms. Our functional MRI analysis is the first to examine brain function, and to report cerebellar dysfunction, in a patient presenting with cognitive/psychiatric symptoms found to have a structural abnormality compressing the cerebellum. These neuroimaging findings are inherently limited due to their correlational nature but provide unprecedented evidence suggesting that cerebellar compression may be associated with cerebellar dysfunction. Exome gene sequencing revealed additional etiological possibilities, highlighting the complexity of this field of cerebellar clinical and scientific practice. Our findings and discussion may guide future investigations addressing an important knowledge gap-namely, is there a link between cerebellar compression (including arachnoid cysts and possibly other forms of cerebellar compression such as Chiari malformation), cerebellar dysfunction (including fMRI abnormalities reported here), and neuropsychiatric symptoms?
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Cistos Aracnóideos/diagnóstico por imagem , Doenças Cerebelares/diagnóstico por imagem , Cerebelo/diagnóstico por imagem , Transtornos Mentais/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Adulto , Cistos Aracnóideos/complicações , Cistos Aracnóideos/cirurgia , Doenças Cerebelares/complicações , Doenças Cerebelares/cirurgia , Cerebelo/cirurgia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Transtornos Mentais/complicações , Transtornos Mentais/cirurgia , Transtornos do Neurodesenvolvimento/complicações , Transtornos do Neurodesenvolvimento/cirurgiaRESUMO
A 62-year-old male presented to hospital with acute aphasia. His past medical history was significant for a previous left middle cerebral artery stroke, from which he fully recovered, hypertension, dyslipidemia, coronary artery disease, one episode of atrial fibrillation postoperatively, and thalidomide exposure in utero. Although initially he was thought to be aphasic, on further examination, he demonstrated significant abulia. His level of consciousness was normal, and neurological examination was otherwise unremarkable. A CT angiogram of the head and neck was performed. The patient was not a candidate for acute therapy, as he had established stroke on imaging, and the time of onset was unclear.
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Infarto Encefálico/etiologia , Círculo Arterial do Cérebro/anormalidades , Infarto Encefálico/patologia , Núcleo Caudado/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Neurology and psychiatry share common historical origins and rely on similar tools to study brain disorders. Yet the practical integration of medical and scientific approaches across these clinical neurosciences remains elusive. Although much has been written about the need to incorporate emerging systems-level, cellular-molecular, and genetic-epigenetic advances into a science of mind for psychiatric disorders, less attention has been given to applying clinical neuroscience principles to conceptualize neurologic conditions with an integrated neurobio-psycho-social approach. In this perspective article, the authors briefly outline the historically interwoven and complicated relationship between neurology and psychiatry. Through a series of vignettes, the authors then illustrate how some traditional psychiatric conditions are being reconceptualized in part as disorders of neurodevelopment and awareness. They emphasize the intersection of neurology and psychiatry by highlighting conditions that cut across traditional diagnostic boundaries. The authors argue that the divide between neurology and psychiatry can be narrowed by moving from lesion-based toward circuit-based understandings of neuropsychiatric disorders, from unidirectional toward bidirectional models of brain-behavior relationships, from exclusive reliance on categorical diagnoses toward transdiagnostic dimensional perspectives, and from silo-based research and treatments toward interdisciplinary approaches. The time is ripe for neurologists and psychiatrists to implement an integrated clinical neuroscience approach to the assessment and management of brain disorders. The subspecialty of behavioral neurology & neuropsychiatry is poised to lead the next generation of clinicians to merge brain science with psychological and social-cultural factors. These efforts will catalyze translational research, revitalize training programs, and advance the development of impactful patient-centered treatments.
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Encefalopatias/fisiopatologia , Encéfalo/fisiopatologia , Transtornos Mentais/fisiopatologia , Neurologia , Psiquiatria , Adolescente , Adulto , Encéfalo/fisiologia , Encefalopatias/psicologia , Criança , Humanos , Transtornos Mentais/psicologia , Neurociências , Adulto JovemRESUMO
Neuropsychiatry services provide specialist input into the assessment and management of behavioral symptoms associated with a range of neurological conditions, including epilepsy. Despite the centrality of epilepsy to neuropsychiatry and the recent expansion of neuropsychiatry service provision, little is known about the clinical characteristics of patients with epilepsy who are routinely seen by a specialist neuropsychiatry service. This retrospective study filled this gap by retrospectively evaluating a naturalistic series of 60 consecutive patients with epilepsy referred to and assessed within a neuropsychiatry setting. Fifty-two patients (86.7%) had active epilepsy and were under the ongoing care of the referring neurologist for seizure management. The majority of patients (N=42; 70.0%) had a diagnosis of localization-related epilepsy, with temporal lobe epilepsy as the most common epilepsy type (N=37; 61.7%). Following clinical assessment, 39 patients (65.0%) fulfilled formal diagnostic criteria for at least one psychiatric disorder; nonepileptic attack disorder (N=37; 61.7%), major depression (N=23; 38.3%), and generalized anxiety disorder (N=16; 26.7%) were the most commonly diagnosed comorbidities. The clinical characteristics of patients seen in specialist neuropsychiatry settings are in line with the results from previous studies in neurology clinics in terms of both epilepsy and psychiatric comorbidity. Our findings confirm the need for the development and implementation of structured care pathways for the neuropsychiatric aspects of epilepsy, with focus on comorbid nonepileptic attacks and affective and anxiety symptoms. This is of particular importance in consideration of the impact of behavioral symptoms on patients' health-related quality of life.
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Ansiedade/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Epilepsia/diagnóstico , Qualidade de Vida , Convulsões/diagnóstico , Adulto , Ansiedade/complicações , Ansiedade/psicologia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/psicologia , Epilepsia/complicações , Epilepsia/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuropsiquiatria , Estudos Retrospectivos , Convulsões/complicações , Convulsões/psicologia , Avaliação de Sintomas , Adulto JovemRESUMO
On the 50th anniversary of Norman Geschwind's seminal paper entitled 'Disconnexion syndrome in animal and man', we pay tribute to his ideas by applying contemporary tractography methods to understand white matter disconnection in 3 classic cases that made history in behavioral neurology. We first documented the locus and extent of the brain lesion from the computerized tomography of Phineas Gage's skull and the magnetic resonance images of Louis Victor Leborgne's brain, Broca's first patient, and Henry Gustave Molaison. We then applied the reconstructed lesions to an atlas of white matter connections obtained from diffusion tractography of 129 healthy adults. Our results showed that in all 3 patients, disruption extended to connections projecting to areas distant from the lesion. We confirmed that the damaged tracts link areas that in contemporary neuroscience are considered functionally engaged for tasks related to emotion and decision-making (Gage), language production (Leborgne), and declarative memory (Molaison). Our findings suggest that even historic cases should be reappraised within a disconnection framework whose principles were plainly established by the associationist schools in the last 2 centuries.
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Encéfalo/patologia , Neurologia/história , Crânio/patologia , Substância Branca/patologia , Tomada de Decisões/fisiologia , Emoções/fisiologia , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Idioma , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , SíndromeRESUMO
Edward Muybridge was an Anglo-American photographer, well known for his pioneering contributions in photography and his invention of the "zoopraxiscope," a forerunner of motion pictures. However, this 19th-century genius, with two original patents in photographic technology, made outstanding contributions in art and neurology alike, the latter being seldom acknowledged. A head injury that he sustained changed his behavior and artistic expression. The shift of his interests from animal motion photography to human locomotion and gait remains a pivotal milestone in our understanding of patterns in biomechanics and clinical neurology, while his own behavioral patterns, owing to an injury to the orbitofrontal cortex, remain a mystery even for cognitive neurologists. The behavioral changes he exhibited and the legal conundrum that followed, including a murder of which he was acquitted, all depict the complexities of his personality and impact of frontal lobe injuries. This article highlights the life journey of Muybridge, drawing parallels with Phineas Gage, whose penetrating head injury has been studied widely. The wide sojourn of Muybridge also illustrates the strong connections that he maintained with Stanford and Pennsylvania universities, which were later considered pinnacles of higher education on the two coasts of the United States.
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Traumatismos Craniocerebrais , Cultura , Pessoas Famosas , Transtornos Mentais/etiologia , Transtornos Mentais/história , Idoso , América , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/história , Traumatismos Craniocerebrais/psicologia , História do Século XIX , História do Século XX , Humanos , Masculino , Fotografação/história , Gravação de Videodisco/históriaRESUMO
We report a fascinating case of a patient with a hyper empathy that appeared after resective epilepsy surgery. This behavioral modification has remained unchanged since the surgery took place 13 years ago. Recent neuropsychological objective assessments confirmed hyper empathy in a self-report questionnaire, and revealed higher affective theory of mind than controls in a "Reading the Mind in the Eyes Task." Temporal lobe epilepsy is the most common form of epilepsy and the investigation of emotional processes after surgery in these patients deserves to be related.
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Sintomas Afetivos/etiologia , Tonsila do Cerebelo/cirurgia , Lobectomia Temporal Anterior/efeitos adversos , Empatia/fisiologia , Hipocampo/cirurgia , Adulto , Feminino , Humanos , Testes Neuropsicológicos , Teoria da Mente/fisiologiaRESUMO
There is a clear need for experts with the requisite knowledge and experience to offer medicolegal opinions pertaining to various neuropsychiatric conditions. There is also an important distinction between clinical and medicolegal roles, and the need for training and expertise applicable to forensic assessment. But there remain few available experts with credentials spanning neuropsychiatry and forensic assessment. This creates a dilemma whereby parties involved in litigation featuring neuropsychiatric illness or injury are frequently forced to choose between experts with either knowledge and skills applicable to neuropsychiatric conditions or experts with skills and experience applicable to forensic assessment. Either choice introduces risk. Whether flawed medicolegal opinions are a consequence of deficient medical knowledge or an inadequate forensic evaluation process, the result remains the same, with triers of fact potentially being exposed to problematic testimony. There is, however, a more fundamental problem that implicates patient care more broadly: spurious dichotomies created by the historical segregation of psychiatry and neurology. Optimizing clinical care for patients with neuropsychiatric conditions, improving medical education in support of such care, and enabling forensic neuropsychiatric assessment must then start with more proactive efforts to reintegrate psychiatry and neurology.
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Prova Pericial , Neurologistas , Humanos , Neurologistas/legislação & jurisprudência , Prova Pericial/legislação & jurisprudência , Psiquiatria Legal , Neurologia , Papel do Médico , Medicina Legal , Transtornos Mentais/diagnósticoRESUMO
This study investigates audiogenic epilepsy in Krushinsky-Molodkina (KM) rats, questioning the efficacy of conventional EEG techniques in capturing seizures during animal restraint. Using a wireless EEG system that allows unrestricted movement, our aim was to gather ecologically valid data. Nine male KM rats, prone to audiogenic seizures, received implants of wireless EEG transmitters that target specific seizure-related brain regions. These regions included the inferior colliculus (IC), pontine reticular nucleus, oral part (PnO), ventrolateral periaqueductal gray (VLPAG), dorsal area of the secondary auditory cortex (AuD), and motor cortex (M1), facilitating seizure observation without movement constraints. Our findings indicate that targeted neural intervention via electrode implantation significantly reduced convulsive seizures in approximately half of the subjects, suggesting therapeutic potential. Furthermore, the amplitude of brain activity in the IC, PnO, and AuD upon audiogenic stimulus onset significantly influenced seizure severity and nature, highlighting these areas as pivotal for epileptic propagation. Severe cases exhibited dual waves of seizure generalization, indicative of intricate neural network interactions. Distinctive interplay between specific brain regions, disrupted during convulsive activity, suggests neural circuit reconfiguration in response to escalating seizure intensity. These discoveries challenge conventional methodologies, opening avenues for novel approaches in epilepsy research and therapeutic interventions.
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The Neurodevelopmental Effects of Antiepileptic Drugs (NEAD) study is a prospective observational multicenter study in the USA and UK, which enrolled pregnant women with epilepsy on antiepileptic drug (AED) monotherapy from 1999 to 2004. The study aimed to determine if differential long-term neurodevelopmental effects exist across four commonly used AEDs (carbamazepine, lamotrigine, phenytoin, and valproate). In this report, we examine fetal AED exposure effects on adaptive and emotional/behavioral functioning at 6years of age in 195 children (including three sets of twins) whose parent (in most cases, the mother) completed at least one of the rating scales. Adjusted mean scores for the four AED groups were in the low average to average range for parent ratings of adaptive functioning on the Adaptive Behavior Assessment System-Second Edition (ABAS-II) and for parent and teacher ratings of emotional/behavioral functioning on the Behavior Assessment System for Children (BASC). However, children whose mothers took valproate during pregnancy had significantly lower General Adaptive Composite scores than the lamotrigine and phenytoin groups. Further, a significant dose-related performance decline in parental ratings of adaptive functioning was seen for both valproate and phenytoin. Children whose mothers took valproate were also rated by their parents as exhibiting significantly more atypical behaviors and inattention than those in the lamotrigine and phenytoin groups. Based upon BASC parent and teacher ratings of attention span and hyperactivity, children of mothers who took valproate during their pregnancy were at a significantly greater risk for a diagnosis of ADHD. The increased likelihood of difficulty with adaptive functioning and ADHD with fetal valproate exposure should be communicated to women with epilepsy who require antiepileptic medication. Finally, additional research is needed to confirm these findings in larger prospective study samples, examine potential risks associated with other AEDs, better define the risks to the neonate that are associated with AEDs for treatment of seizures, and understand the underlying mechanisms of adverse AED effects on the immature brain.
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Anticonvulsivantes/efeitos adversos , Síndrome de Adaptação Geral/induzido quimicamente , Transtornos do Humor/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Adaptação Psicológica/efeitos dos fármacos , Análise de Variância , Criança , Epilepsia/tratamento farmacológico , Feminino , Humanos , Masculino , Análise Multivariada , Gravidez , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Escalas de Graduação PsiquiátricaRESUMO
Mindfulness is a state of awareness characterized by open and non-judgmental recognition of thoughts and sensations and an ability to resist the usual wandering of an individual's attention. Usually achieved by meditation, mindfulness is recognized as a treatment for chronic pain. Evidence, thus far, has been characterized by poor quality trials and mixed results, but a growing body of research is further investigating its effectiveness. Despite inconclusive evidence, the inherent difficulties of mindfulness research, and problems of accessibility in rural settings, mindfulness meditation is an emerging treatment strategy for many chronic pain patients. This report presents the case of a patient admitted to a rural hospital in New South Wales, whose quality of life was severely impacted by chronic pain.
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Neurobehavioral and neuropsychiatric symptoms are highly prevalent among individuals diagnosed with cognitive impairment or dementia and impact the quality of life for patients and caregivers alike. Diagnosis and management of these conditions (including primarily depression, anxiety, apathy, psychosis, agitation, and aggression) is crucial to optimal patient care outcomes in clinical practice. The present article provides a practical review of diagnostic approaches and management strategies for behavioral and neuropsychiatric disorders arising in patients with cognitive impairment, up to and including dementia.
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Disfunção Cognitiva , Demência , Comportamento Problema , Transtornos Psicóticos , Humanos , Qualidade de Vida , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Transtornos Psicóticos/complicações , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/terapia , Demência/complicações , Demência/diagnóstico , Demência/terapiaRESUMO
In this systematic review, we evaluate the safety, tolerability, and immunogenicity of vaccination efforts against Alzheimer's disease (AD) in human subjects from both ongoing and completed vaccination trials. Databases like PubMed, Embase, and Scopus were used to identify relevant articles on completed vaccination trials whereas the clinicaltrials.gov database was used for identifying ongoing clinical trials for vaccination against AD in humans until January 2022. Only interventional randomized or non-randomized clinical trials which reported on the safety and immunogenicity of vaccine against AD in humans were included. Cochrane risk of bias tool-2 (RoB-2) or risk of bias in non-randomized studies- of intervention (ROBINS-I) was used for risk of bias assessment as appropriate. A narrative descriptive synthesis of the findings was done. Sixteen randomized/non-randomized clinical trials (phase I: six and phase II: 10) for seven different types of vaccines against AD were identified comprising a total of 2080 participants. Apart from the development of meningoencephalitis in 6% of patients receiving AN1792 in an interrupted phase II trial, the rest of the trial reported promising results on the safety and immunogenicity of vaccines. While only a subset of reported adverse events was treatment related, none of the fatalities reported during the trial were considered related to vaccine administration. The serological response rate ranged from 100% (4/16 trials) to 19.7% in an interrupted trial. Although current trials show promising results, adequately powered phase III studies are needed to conclusively establish the safety, immunogenicity and therapeutic efficacy of vaccines.