Conducting Non-COVID-19 Clinical Trials during the Pandemic: Can Today's Learning Impact Framework Efficiency?

The COVID-19 pandemic has severely disrupted non-coronavirus clinical trials. In the case of life-threatening diseases, such as cancer, this is particularly dangerous, as treatment cannot simply be stopped. In the EU, guidelines for the management of ongoing studies were issued; however, national coordination is still lacking. This article aims to raise awareness on the struggle of managing ongoing clinical trials in the EU during the pandemic. The goals are to bring attention, from a legal and regulatory point of view to the difficulties faced by those involved in clinical research, and to critically position the current hurdles against the backdrop of the existing legal and ethical framework. We investigated the EU guidance and the national approaches of all EU/EEA Member States, and critically discussed selected issues. We argue that the crisis may be an opportunity to foresee meaningful changes in the EU clinical trials framework post-COVID-19.

Implementation of Regulation (EU) No 536/2014 as a Non-commercial Sponsor: An Internal Survey and a Descriptive Analysis of Timelines.

INTRODUCTION: To safeguard the safety and interests of subjects participating in clinical trials, their conduct is heavily regulated. The EU Clinical Trials Regulation (CTR) 536/2014 brings fundamental changes that will require sponsors to adapt their current way of working. One major change is the significant shortening of the permitted reply timelines to requests for information (RFI), which may require adaptations to established processes within an organisation. This study aimed to assess these reply timelines at the European Organisation for Research and Treatment of Cancer (EORTC), a non-commercial sponsor. Additionally, it aimed to investigate how the impact of the different CTR requirements is perceived by the organisation's staff. METHODS: A retrospective analysis was performed to assess the length of reply to grounds of non-acceptance (GNA) timelines. Questionnaires were circulated to internal staff to assess their views on the impact of important changes the CTR introduces on the organisation's processes. RESULTS: The average reply time to comments from regulators was 27.5 days, which is longer than the 12-day time limit required by CTR, which indicates that the organisation's processes require re-optimization to allow efficient activation of trials compliant with the new legislation. The majority of the staff that completed the questionnaire assessed the impact the CTR would have on the organisation to be positive. Finally, there was a large consensus about the changes related to the submission timelines, transition period and the user management of the Clinical Trial Information System (CTIS) having a very important impact on the organisation as a whole. Participants referred to the streamlined process of a clinical trial in different countries as foreseen in the CTR, as an aspect that would benefit the organisation. DISCUSSION: For all retrospectively studied timelines, the average timelines to reply combined for competent authorities (CA) and ethics committees (EC) were longer than the 12 days allowed under the CTR. EORTC will have to adapt internal processes to meet the time limit imposed by the CTR without compromising its scientific integrity. The questionnaire respondents had the required expertise to provide an opinion on the CTR's impact on the organisation. There was a large consensus about the changes relating to the submission timelines having a very important impact on the organisation. This observation is in line with the results of the retrospective part of this study. CONCLUSION: Based on the results of the retrospective and prospective parts of the study, it is clear that the shorter reply timelines are the main factor that will affect the organisation. EORTC has spent significant resources in adapting its processes to comply with the CTR's new requirements. Experience with the first studies under the new regulation can be utilized to implement further process adaptations.

Comparative analysis of different peptidyl-prolyl isomerases reveals FK506-binding protein 12 as the most potent enhancer of alpha-synuclein aggregation.

FK506-binding proteins (FKBPs) are members of the immunophilins, enzymes that assist protein folding with their peptidyl-prolyl isomerase (PPIase) activity. Some non-immunosuppressive inhibitors of these enzymes have neuroregenerative and neuroprotective properties with an unknown mechanism of action. We have previously shown that FKBPs accelerate the aggregation of α-synuclein (α-SYN) in vitro and in a neuronal cell culture model for synucleinopathy. In this study we investigated whether acceleration of α-SYN aggregation is specific for the FKBP or even the PPIase family. Therefore, we studied the effect of several physiologically relevant PPIases, namely FKBP12, FKBP38, FKBP52, FKBP65, Pin1, and cyclophilin A, on α-SYN aggregation in vitro and in neuronal cell culture. Among all PPIases tested in vitro, FKBP12 accelerated α-SYN aggregation the most. Furthermore, only FKBP12 accelerated α-SYN fibril formation at subnanomolar concentrations, pointing toward an enzymatic effect. Although stable overexpression of various FKBPs enhanced the aggregation of α-SYN and cell death in cell culture, they were less potent than FKBP12. When FKBP38, FKBP52, and FKBP65 were overexpressed in a stable FKBP12 knockdown cell line, they could not fully restore the number of α-SYN inclusion-positive cells. Both in vitro and cell culture data provide strong evidence that FKBP12 is the most important PPIase modulating α-SYN aggregation and validate the protein as an interesting drug target for Parkinson disease.

Inhibition of FK506 binding proteins reduces alpha-synuclein aggregation and Parkinson's disease-like pathology.

alpha-Synuclein (alpha-SYN) is a key player in the pathogenesis of Parkinson's disease (PD). In pathological conditions, the protein is present in a fibrillar, aggregated form inside cytoplasmic inclusions called Lewy bodies. Members of the FK506 binding protein (FKBP) family are peptidyl-prolyl isomerases that were shown recently to accelerate the aggregation of alpha-SYN in vitro. We now established a neuronal cell culture model for synucleinopathy based on oxidative stress-induced alpha-SYN aggregation and apoptosis. Using high-content analysis, we examined the role of FKBPs in aggregation and apoptotic cell death. FK506, a specific inhibitor of this family of proteins, inhibited alpha-SYN aggregation and neuronal cell death in this synucleinopathy model dose dependently. Knockdown of FKBP12 or FKBP52 reduced the number of alpha-SYN aggregates and protected against cell death, whereas overexpression of FKBP12 or FKBP52 accelerated both aggregation of alpha-SYN and cell death. Thus, FK506 likely targets FKBP members in the cell culture model. Furthermore, oral administration of FK506 after viral vector-mediated overexpression of alpha-SYN in adult mouse brain significantly reduced alpha-SYN aggregate formation and neuronal cell death. Our data explain previously described neuroregenerative and neuroprotective effects of immunophilin ligands and validate FKBPs as a novel drug target for the causative treatment of PD.

Will molecular target agents enable the multidisciplinary treatment in stage IV gastric cancer?

A detailed molecular characterization of gastric cancer has been revealed by global initiatives and a number of new molecular agents are under investigation. Currently only trastuzumab, a monoclonal antibody for human epidermal growth factor receptor 2 (HER2), is clinically used for HER2 positive advanced gastric cancer patients and ramucirumab, a monoclonal antibody directed against the extracellular ligand-binding domain of vascular endothelial growth factor receptor (VEGFR)2, can be used in second line. However, despite the progress in gastric cancer treatment, the prognosis of stage IV gastric cancer patients remains dismal. To achieve a remarkable improvement in the prognosis of patients, a multidisciplinary treatment approach with the help of effective molecular target agents should be considered. So far the role of multidisciplinary treatment for stage IV gastric cancer is still uncertain due to limited available data and absence of long-lasting tumor control with systemic therapy. Herein, an overview of the latest developments of molecular targeted agents for gastric cancer in advanced stages, in the perioperative setting and in oligometastatic disease is provided. The possibility of a multidisciplinary strategy using molecular target agents and surgery for stage IV gastric cancer is also assessed.

High-content analysis of α-synuclein aggregation and cell death in a cellular model of Parkinson's disease.

BACKGROUND: Alpha-synuclein (α-SYN) aggregates represent a key feature of Parkinson's disease, but the exact relationship between α-SYN aggregation and neurodegeneration remains incompletely understood. Therefore, the availability of a cellular assay that allows medium-throughput analysis of α-SYN-linked pathology will be of great value for studying the aggregation process and for advancing α-SYN-based therapies. NEW METHOD: Here we describe a high-content neuronal cell assay that simultaneously measures oxidative stress-induced α-SYN aggregation and apoptosis. RESULTS: We optimized an automated and reproducible assay to quantify both α-SYN aggregation and cell death in human SH-SY5Y neuroblastoma cells. COMPARISON WITH EXISTING METHODS: Quantification of α-SYN aggregates in cells has typically relied on manual imaging and counting or cell-free assays, which are time consuming and do not allow a concurrent analysis of cell viability. Our high-content analysis method for quantification of α-SYN aggregation allows simultaneous measurements of multiple cell parameters at a single-cell level in a fast, objective and automated manner. CONCLUSIONS: The presented analysis approach offers a rapid, objective and multiparametric approach for the screening of compounds and genes that might alter α-SYN aggregation and/or toxicity.

Alpha-synuclein-induced neurodegeneration is exacerbated in PINK1 knockout mice.

Loss-of-function mutations in the PINK1 gene lead to recessive forms of Parkinson's disease. Animal models with depleted PINK1 expression have failed to reproduce significant nigral dopaminergic neurodegeneration and clear alpha-synuclein pathology, main characteristics of the disease. In this study, we investigated whether alpha-synuclein pathology is altered in the absence of PINK1 in cell culture and in vivo. We observed that downregulation of PINK1 enhanced alpha-synuclein aggregation and apoptosis in a neuronal cell culture model for synucleinopathy. Silencing of PINK1 expression in mouse substantia nigra using recombinant adeno-associated viral vectors did not induce dopaminergic neurodegeneration in a long-term study up to 10 months, nor did it enhance or accelerate dopaminergic neurodegeneration after alpha-synuclein overexpression. However, in PINK1 knockout mice, overexpression of alpha-synuclein in the substantia nigra resulted in enhanced dopaminergic neurodegeneration as well as significantly higher levels of alpha-synuclein phosphorylation at serine 129 at 4 weeks postinjection. In conclusion, our results demonstrate that total loss of PINK1 leads to an increased sensitivity to alpha-synuclein-induced neuropathology and cell death in vivo.

The remarkable conformational plasticity of alpha-synuclein: blessing or curse?

The aggregation of the protein alpha-synuclein (α-SYN) is believed to be a critical event in Parkinson's disease (PD). α-SYN is characterized by a remarkable conformational plasticity, adopting different conformations depending on the environment. In vitro, α-SYN lacks a well-defined structure. Therefore, it was classified as an 'intrinsically disordered protein'. A debate has recently begun over how α-SYN behaves in the cell: is it an intrinsically disordered protein or a stable tetramer with a low propensity for aggregation? In this review, we discuss the aggregation of α-SYN and describe factors that influence this process and their potential relevance in PD pathogenesis. We address the ways in which aggregated α-SYN mediates toxicity and might lead to PD, and propose possible therapeutic strategies.

Unraveling the role of peptidyl-prolyl isomerases in neurodegeneration.

Immunophilins are a family of highly conserved proteins with a peptidyl-prolyl isomerase activity that binds immunosuppressive drugs such as FK506, cyclosporin A, and rapamycin. Immunophilins can be divided into two subfamilies, the cyclophilins, and the FK506 binding proteins (FKBPs). Next to the immunophilins, a third group of peptidyl-prolyl isomerases exist, the parvulins, which do not influence the immune system. The beneficial role of immunophilin ligands in neurodegenerative disease models has been known for more than a decade but remains largely unexplained in terms of molecular mechanisms. In this review, we summarize reported effects of parvulins, immunophilins, and their ligands in the context of neurodegeneration. We focus on the role of FKBP12 in Parkinson's disease and propose it as a novel drug target for therapy of Parkinson's disease.

In vitro DNA tethering of HIV-1 integrase by the transcriptional coactivator LEDGF/p75.

Although LEDGF/p75 is believed to act as a cellular cofactor of lentiviral integration by tethering integrase (IN) to chromatin, there is no good in vitro model to analyze this functionality. We designed an AlphaScreen assay to study how LEDGF/p75 modulates the interaction of human immunodeficiency virus type 1 IN with DNA. IN bound with similar affinity to DNA mimicking the long terminal repeat or to random DNA. While LEDGF/p75 bound DNA strongly, a mutant of LEDGF/p75 with compromised nuclear localization signal (NLS)/AT hook interacted weakly, and the LEDGF/p75 PWWP domain did not interact, corroborating previous reports on the role of NLS and AT hooks in charge-dependent DNA binding. LEDGF/p75 stimulated IN binding to DNA 10-fold to 30-fold. Stimulation of IN-DNA binding required a direct interaction between IN and the C-terminus of LEDGF/p75. Addition of either the C-terminus of LEDGF/p75 (amino acids 325-530) or LEDGF/p75 mutated in the NLS/AT hooks interfered with IN binding to DNA. Our results are consistent with an in vitro model of LEDGF/p75-mediated tethering of IN to DNA. The inhibition of IN-DNA interaction by the LEDGF/p75 C-terminus may provide a novel strategy for the inhibition of HIV IN activity and may explain the potent inhibition of HIV replication observed after the overexpression of C-terminal fragments in cell culture.