JC virus-induced progressive multifocal leukoencephalopathy in a presumably healthy patient.

BACKGROUND: JC virus (JCV) is common among healthy individuals and remains latent but may be reactivated under immunosuppressive conditions, resulting in progressive multifocal leukoencephalopathy (PML). Here, we present a rare case of PML caused by JC virus infection in a previously healthy and immunocompetent patient. CASE PRESENTATION: A 67-year-old female without any disease history was admitted after presenting with rapidly progressive dementia. The preoperative diagnosis was progressive multifocal leukoencephalopathy, and corticosteroid treatment did not improve the symptoms. Brain lesions were surgically sampled, and JCV infection was confirmed by high-throughput DNA gene detection. This patient received a combined treatment of mirtazapine, mefloquine, and traditional Chinese herbs, and had stabilization of the disease on followed-up. CONCLUSIONS: Although it is a rare, this case demonstrates that JC virus infection within the brain occurs in apparently healthy people. This case may increase our understanding of virus infection when facing the coronavirus epidemic in recent years, considering that similar medications were used.

Unlike Chloroquine, Mefloquine Inhibits SARS-CoV-2 Infection in Physiologically Relevant Cells.

Despite the development of specific therapies against severe acute respiratory coronavirus 2 (SARS-CoV-2), the continuous investigation of the mechanism of action of clinically approved drugs could provide new information on the druggable steps of virus-host interaction. For example, chloroquine (CQ)/hydroxychloroquine (HCQ) lacks in vitro activity against SARS-CoV-2 in TMPRSS2-expressing cells, such as human pneumocyte cell line Calu-3, and likewise, failed to show clinical benefit in the Solidarity and Recovery clinical trials. Another antimalarial drug, mefloquine, which is not a 4-aminoquinoline like CQ/HCQ, has emerged as a potential anti-SARS-CoV-2 antiviral in vitro and has also been previously repurposed for respiratory diseases. Here, we investigated the anti-SARS-CoV-2 mechanism of action of mefloquine in cells relevant for the physiopathology of COVID-19, such as Calu-3 cells (that recapitulate type II pneumocytes) and monocytes. Molecular pathways modulated by mefloquine were assessed by differential expression analysis, and confirmed by biological assays. A PBPK model was developed to assess mefloquine's optimal doses for achieving therapeutic concentrations. Mefloquine inhibited SARS-CoV-2 replication in Calu-3, with an EC50 of 1.2 µM and EC90 of 5.3 µM. It reduced SARS-CoV-2 RNA levels in monocytes and prevented virus-induced enhancement of IL-6 and TNF-α. Mefloquine reduced SARS-CoV-2 entry and synergized with Remdesivir. Mefloquine's pharmacological parameters are consistent with its plasma exposure in humans and its tissue-to-plasma predicted coefficient points suggesting that mefloquine may accumulate in the lungs. Altogether, our data indicate that mefloquine's chemical structure could represent an orally available host-acting agent to inhibit virus entry.

A SARS-CoV-2 cytopathicity dataset generated by high-content screening of a large drug repurposing collection.

SARS-CoV-2 is a novel coronavirus responsible for the COVID-19 pandemic, in which acute respiratory infections are associated with high socio-economic burden. We applied high-content screening to a well-defined collection of 5632 compounds including 3488 that have undergone previous clinical investigations across 600 indications. The compounds were screened by microscopy for their ability to inhibit SARS-CoV-2 cytopathicity in the human epithelial colorectal adenocarcinoma cell line, Caco-2. The primary screen identified 258 hits that inhibited cytopathicity by more than 75%, most of which were not previously known to be active against SARS-CoV-2 in vitro. These compounds were tested in an eight-point dose response screen using the same image-based cytopathicity readout. For the 67 most active molecules, cytotoxicity data were generated to confirm activity against SARS-CoV-2. We verified the ability of known inhibitors camostat, nafamostat, lopinavir, mefloquine, papaverine and cetylpyridinium to reduce the cytopathic effects of SARS-CoV-2, providing confidence in the validity of the assay. The high-content screening data are suitable for reanalysis across numerous drug classes and indications and may yield additional insights into SARS-CoV-2 mechanisms and potential therapeutic strategies.

Antimalarial artemisinin-based combination therapies (ACT) and COVID-19 in Africa: In vitro inhibition of SARS-CoV-2 replication by mefloquine-artesunate.

OBJECTIVES: At the end of November 2019, a novel coronavirus responsible for respiratory tract infections (COVID-19) emerged in China. Despite drastic containment measures, this virus, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spread in Asia and Europe. The pandemic is ongoing with a particular hotspot in Southern Europe and America; many studies predicted a similar epidemic in Africa, as is currently seen in Europe and the United States of America. However, reported data have not confirmed these predictions. One of the hypotheses that could explain the later emergence and spread of COVID-19 pandemic in African countries is the use of antimalarial drugs to treat malaria, and specifically, artemisinin-based combination therapy (ACT). METHODS: The antiviral activity of fixed concentrations of ACT at concentrations consistent with those observed in human plasma when ACT is administered at oral doses for uncomplicated malaria treatment was evaluatedin vitro against a clinically isolated SARS-CoV-2 strain (IHUMI-3) in Vero E6 cells. RESULTS: Mefloquine-artesunate exerted the highest antiviral activity with % inhibition of 72.1 ± 18.3 % at expected maximum blood concentration (Cmax) for each ACT drug at doses commonly administered in malaria treatment. All the other combinations, artesunate-amodiaquine, artemether-lumefantrine, artesunate-pyronaridine, or dihydroartemisinin-piperaquine, showed antiviral inhibition in the same ranges (27.1 to 34.1 %). CONCLUSIONS: Antimalarial drugs for which concentration data in the lungs are available are concentrated from 10 to 160 fold more in the lungs than in blood. Thesein vitro results reinforce the hypothesis that antimalarial drugs could be effective as an anti-COVID-19 treatment.