Accelerating Medicines Partnership® Schizophrenia (AMP® SCZ): Rationale and Study Design of the Largest Global Prospective Cohort Study of Clinical High Risk for Psychosis

This article describes the rationale, aims, and methodology of the Accelerating Medicines Partnership® Schizophrenia (AMP® SCZ). This is the largest international collaboration to date that will develop algorithms to predict trajectories and outcomes of individuals at clinical high risk (CHR) for psychosis and to advance the development and use of novel pharmacological interventions for CHR individuals. We present a description of the participating research networks and the data processing analysis and coordination center, their processes for data harmonization across 43 sites from 13 participating countries (recruitment across North America, Australia, Europe, Asia, and South America), data flow and quality assessment processes, data analyses, and the transfer of data to the National Institute of Mental Health (NIMH) Data Archive (NDA) for use by the research community. In an expected sample of approximately 2000 CHR individuals and 640 matched healthy controls, AMP SCZ will collect clinical, environmental, and cognitive data along with multimodal biomarkers, including neuroimaging, electrophysiology, fluid biospecimens, speech and facial expression samples, novel measures derived from digital health technologies including smartphone-based daily surveys, and passive sensing as well as actigraphy. The study will investigate a range of clinical outcomes over a 2-year period, including transition to psychosis, remission or persistence of CHR status, attenuated positive symptoms, persistent negative symptoms, mood and anxiety symptoms, and psychosocial functioning. The global reach of AMP SCZ and its harmonized innovative methods promise to catalyze the development of new treatments to address critical unmet clinical and public health needs in CHR individuals.

Drug development for Autism Spectrum Disorder (ASD): Progress, challenges, and future directions

In 2017, facing lack of progress and failures encountered in targeted drug development for Autism Spectrum Disorder (ASD) and related neurodevelopmental disorders, the ISCTM with the ECNP created the ASD Working Group charged to identify barriers to progress and recommending research strategies for the field to gain traction. Working Group international academic, regulatory and industry representatives held multiple in-person meetings, teleconferences, and subgroup communications to gather a wide range of perspectives on lessons learned from extant studies, current challenges, and paths for fundamental advances in ASD therapeutics. This overview delineates the barriers identified, and outlines major goals for next generation biomedical intervention development in ASD. Current challenges for ASD research are many: heterogeneity, lack of validated biomarkers, need for improved endpoints, prioritizing molecular targets, comorbidities, and more. The Working Group emphasized cautious but unwavering optimism for therapeutic progress for ASD core features given advances in the basic neuroscience of ASD and related disorders. Leveraging genetic data, intermediate phenotypes, digital phenotyping, big database discovery, refined endpoints, and earlier intervention, the prospects for breakthrough treatments are substantial. Recommendations include new priorities for expanded research funding to overcome challenges in translational clinical ASD therapeutic research.

Sex and gender differences in Alzheimer's disease: current challenges and implications for clinical practice: Position paper of the Dementia and Cognitive Disorders Panel of the European Academy of Neurology

Alzheimer's disease (AD) is characterized by high heterogeneity in disease manifestation, progression and risk factors. High phenotypic variability is currently regarded as one of the largest hurdles in early diagnosis and in the design of clinical trials; there is therefore great interest in identifying factors driving variability that can be used for patient stratification. In addition to genetic and lifestyle factors, the individual's sex and gender are emerging as crucial drivers of phenotypic variability. Evidence exists on sex and gender differences in the rate of cognitive deterioration and brain atrophy, and in the effect of risk factors as well as in the patterns of diagnostic biomarkers. Such evidence might be of high relevance and requires attention in clinical practice and clinical trials. However, sex and gender differences are currently seldom appreciated; importantly, consideration of sex and gender differences is not currently a focus in the design and analysis of clinical trials for AD. The objective of this position paper is (i) to provide an overview of known sex and gender differences that might have implications for clinical practice, (ii) to identify the most important knowledge gaps in the field (with a special regard to clinical trials) and (iii) to provide conclusions for future studies. This scientific statement is endorsed by the European Academy of Neurology.

Clinical trials and late-stage drug development for Alzheimer's disease: an appraisal from 1984 to 2014

The modern era of drug development for Alzheimer's disease began with the proposal of the cholinergic hypothesis of memory impairment and the 1984 research criteria for Alzheimer's disease. Since then, despite the evaluation of numerous potential treatments in clinical trials, only four cholinesterase inhibitors and memantine have shown sufficient safety and efficacy to allow marketing approval at an international level. Although this is probably because the other drugs tested were ineffective, inadequate clinical development methods have also been blamed for the failures. Here, we review the development of treatments for Alzheimer's disease during the past 30 years, considering the drugs, potential targets, late-stage clinical trials, development methods, emerging use of biomarkers and evolution of regulatory considerations in order to summarize advances and anticipate future developments. We have considered late-stage Alzheimer's disease drug development from 1984 to 2013, including individual clinical trials, systematic and qualitative reviews, meta-analyses, methods, commentaries, position papers and guidelines. We then review the evolution of drugs in late clinical development, methods, biomarkers and regulatory issues. Although a range of small molecules and biological products against many targets have been investigated in clinical trials, the predominant drug targets have been the cholinergic system and the amyloid cascade. Trial methods have evolved incrementally: inclusion criteria have largely remained focused on mild-to-moderate Alzheimer's disease criteria, recently extending to early or prodromal Alzheimer disease or 'mild cognitive impairment due to Alzheimer's disease', for drugs considered to be disease modifying. The duration of trials has remained at 6-12 months for drugs intended to improve symptoms; 18- to 24-month trials have been established for drugs expected to attenuate clinical course. Cognitive performance, activities of daily living, global change and severity ratings have persisted as the primary clinically relevant outcomes. Regulatory guidance and oversight have evolved to allow for enrichment of early-stage Alzheimer's disease trial samples using biomarkers and phase-specific outcomes. In conclusion, validated drug targets for Alzheimer's disease remain to be developed. Only drugs that affect an aspect of cholinergic function have shown consistent, but modest, clinical effects in late-phase trials. There is opportunity for substantial improvements in drug discovery and clinical development methods.

Search for peripheral biomarkers in patients affected by acutely psychotic bipolar disorder: a proteomic approach

Data on neurobiological mechanisms underlying mood disorders are elusive; the aetiology of such states is multifactorial, including genetic predisposition and environmental factors. Diagnosis is currently being made only on an interview-based methodology. Biological markers, which could improve the current classification, and in perspective, stratify patients on a biological basis into more homogeneous clinically distinct subgroups, are highly needed. We describe here a comparative proteomic analysis of peripheral lymphocytes from patients affected by acute psychotic bipolar disorder (PBD) (n = 15), major depressive episode (MDE) with no personal or family history of psychosis (n = 11), and a group of demographically matched healthy controls (HC) (n = 15). All patients were evaluated by means of Structured Clinical Interview for DSM-IV-Patient version (SCID-I-P), Positive and Negative Symptoms Scale (PANSS), Young Mania Rating Scale (YMRS), Hamilton Anxiety Rating Scale (HAM-A) and Hamilton Depression Rating Scale (HAM-D-17) questionnaires. Blood lymphocytes were obtained by gradient separation, and 2-DE was carried out on protein extracts. Significant differences in protein patterns among the three groups were observed. Thirty-six protein spots were found to be differentially expressed in patients compared to controls, which collapsed into 25 different proteins after mass spectrometry identification. Twenty-one of these proteins failed to discriminate between PBD and MDE, suggesting common signatures for these disorders. Nevertheless, after the western blot validation only two of the remaining proteins, namely LIM and SH3 domain protein1, and short-chain specific acyl-CoA dehydrogenase mitochondrial protein, resulted in being significantly upregulated in PBD samples suggesting additional mechanisms that could be associated with the psychotic features of bipolar disorder.

Microvessel length density, total length, and length per neuron in five subcortical regions in schizophrenia

Recent studies (Prabakaran et al. in Mol Psychiat 9:684-697, 2004; Hanson and Gottesman in BMC Med Genet 6:7, 2005; Harris et al. in PLoS ONE 3:e3964, 2008) have suggested that microvascular abnormalities occur in the brains of patients with schizophrenia. To assess the integrity of the microvasculature in subcortical brain regions in schizophrenia, we investigated the microvessel length density, total microvessel length, and microvessel length per neuron using design-based stereologic methods in the caudate nucleus, putamen, nucleus accumbens, mediodorsal nucleus of the thalamus, and lateral nucleus of the amygdala in both hemispheres of 13 postmortem brains from male patients with schizophrenia and 13 age-matched male controls. A general linear model multivariate analysis of variance with diagnosis and hemisphere as fixed factors and illness duration (patients with schizophrenia) or age (controls), postmortem interval and fixation time as covariates showed no statistically significant differences in the brains from the patients with schizophrenia compared to the controls. These data extend our earlier findings in prefrontal cortex area 9 and anterior cingulate cortex area 24 from the same brains (Kreczmanski et al. in Acta Neuropathol 109:510-518, 2005), that alterations in microvessel length density, total length, and particularly length per neuron cannot be considered characteristic features of schizophrenia. As such, compromised brain metabolism and occurrence of oxidative stress in the brains of patients with schizophrenia are likely caused by other mechanisms such as functional disruption in the coupling of cerebral blood flow to neuronal metabolic needs.

Volume, neuron density and total neuron number in five subcortical regions in schizophrenia

Several studies have pointed to alterations in mean volumes, neuron densities and total neuron numbers in the caudate nucleus (CN), putamen, nucleus accumbens (NA), mediodorsal nucleus of the thalamus (MDNT) and lateral nucleus of the amygdala (LNA) in schizophrenia. However, the results of these studies are conflicting and no clear pattern of alterations has yet been established in these subcortical regions, possibly due to differences in quantitative histological methods used as well as differences in the investigated case series. The present study investigates these subcortical regions in both hemispheres of the same post-mortem brains for volume, neuron density and total neuron number with high-precision design-based stereology. The analysed case series consisted of 13 post-mortem brains from male schizophrenic patients [age range: 22-64 years; mean age 51.5 +/- 3.3 years (mean +/- SEM)] and 13 age-matched male controls (age range: 25-65 years; mean age 51.9 +/- 3.1 years). A general linear model multivariate analysis of variance with diagnosis and hemisphere as fixed factors and illness duration (schizophrenic patients) or age (controls), post-mortem interval and fixation time as covariates showed a number of statistically significant alterations in the brains from schizophrenic patients compared with the controls. There was a reduced mean volume of the putamen [-5.0% on the left side (l) and -4.1% on the right side (r)] and the LNA (l: -12.1%, r: -17.6%), and a reduced mean total neuron number in the CN (l: -10.4%, r: -10.2%), putamen (l: -8.1%, r: -11.6%) and the LNA (l: -15.9%, r: -16.2%). These data show a previously unreported, distinct pattern of alterations in mean total neuron numbers in identified subcortical brain regions in a carefully selected sample of brains from schizophrenic patients. The rigorous quantitative analysis of several regions in brains from schizophrenic patients and matched controls is crucial to provide reliable information on the neuropathology of schizophrenia as well as insights about its pathogenesis.