Hydroxychloroquine as Prophylaxis for COVID-19: A Review

Long COVID in autoimmune rheumatic diseases

Consequences of Corona Virus Disease-19 (COVID-19) in patients with rheumatic diseases (RDs) are clinically diverse. SARS-CoV-2 infection has been associated with various autoimmune and rheumatic manifestations over the past three years. Emerging evidence points to the possibility of Long COVID predisposition in rheumatic patients due to the changes in immune regulatory response. The aim of this article was to overview data on the pathobiology of Long COVID in patients with RDs. Related risk factors, clinical characteristics, and prognosis of Long COVID in RDs were analyzed. Relevant articles were retrieved from Medline/PubMed, Scopus, and Directory of Open Access Journals (DOAJ). Diverse mechanisms of viral persistence, chronic low-grade inflammation, lasting production of autoantibodies, endotheliopathy, vascular complications, and permanent tissue damage have been described in association with Long COVID. Patients with RDs who survive COVID-19 often experience severe complications due to the immune disbalance resulting in multiple organ damage. Regular monitoring and treatment are warranted in view of the accumulating evidence.

Population Pharmacokinetics of Hydroxychloroquine Sulfate in Healthcare Workers, Given for Prophylaxis Against Coronavirus Disease 2019 (COVID-19) in India

Healthcare workers (HCWs) and frontline workers were recommended hydroxychloroquine (HCQ) 400 mg twice a day on day 1, followed by 400 mg once weekly for the next 7 weeks, as prophylaxis against COVID-19. There was limited information on the population pharmacokinetics (popPK) of HCQ in an Indian setting when administered for prophylaxis against COVID-19, and hence this study was proposed. It was a multicentric prospective study conducted at 3 sites in India wherein HCWs who were already on HCQ prophylaxis, who were about to start prophylaxis or who had stopped the prophylaxis for any reason were enrolled. Each participant gave 2 to 6 blood samples at different time points and whole-blood HCQ concentrations were assayed using liquid chromatography with tandem mass spectrometry (LC MS/MS). popPK analysis was performed using PUMAS 1.1.0. A total of N = 338 blood samples from N = 121 participants were included in the popPK analysis. A 2-compartment structural model with linear elimination was able to explain the observed data. Body weight was found to be a significant covariate influencing drug clearance. The final model was assessed using goodness-of-fit plots, a visual predictive check and a bootstrap, all of which confirmed that the model was appropriate. Simulations based on the current regimen showed that trough values were below the half-maximal effective concentration (EC50) of 0.7 μmol against COVID-19. A new weight-based dosage regimen was proposed to maintain the trough concentration above the EC50 threshold.

A validated UHPLC-MS/MS method for simultaneous quantification of some repurposed COVID-19 drugs in rat plasma: Application to a pharmacokinetic study

Since the emergence of Corona virus disease (COVID-19) in 2019, a number of medications have been developed and tried to combat the pandemic. In the present study, we develop a LC-MS/MS approach to detect and quantify certain COVID-19 candidate drugs in rat plasma, including Hydroxychloroquine, Favipiravir, Oseltamivir, and Remdesivir. The analytes were separated using Ultra High-Pressure Liquid Chromatography (UHPLC) over a 13-minute run on a C₁₈ column. The extraction solvent for the (QuEChERS) quick, easy, cheap, effective, rugged and safe method was methanol, while the clean-up phase was primary secondary amine (PSA). Satisfactory recoveries were achieved for all compounds ranging from 82.39 to 105.87 %, with standard deviations smaller than 15.7. In terms of precision, accuracy, linearity, matrix effect, and stability, the method was validated according to US FDA criteria. The Limit of Detection (LOD) was determined to be between 0.11 and 10 ppb. The approach was further developed for a modest pharmacokinetic research in laboratory rats, and thus can be suitable for therapeutic drug monitoring in clinical cases under the same treatment.

Safety and Tolerability of Hydroxychloroquine in healthcare workers and first responders for the prevention of COVID-19: WHIP COVID-19 Study

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Hydroxychloroquine chemoprophylaxis is safe in high-risk populations for COVID-19.

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No increased cardiovascular risks were observed with hydroxychloroquine chemoprophylaxis.

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Adverse events were similar between placebo and hydroxychloroquine treatment arms.

Background

Health care workers (HCW) are among the highest risk groups for acquisition of COVID-19 because of occupational exposures. The WHIP COVID-19 Study aimed to evaluate the safety and efficacy of hydroxychloroquine (HCQ) as chemoprophylaxis for SARS-CoV-2 infection in this population.

Methods

HCW, first responders, and other occupationally high-risk participants were enrolled in a randomized, placebo-controlled clinical study of HCQ from April to October 2020. The trial compared daily versus weekly HCQ with placebo and with a prospective cohort on HCQ for autoimmune diseases. Participants were followed for 8 weeks. Serology or a positive polymerase chain reaction test was used to determine laboratory confirmed clinical cases.

Results

A total of 624 participants were randomized to placebo (n = 200), weekly HCQ (n = 201), daily HCQ (n = 197). For the primary safety end point, 279 (44.7%) participants experienced adverse event (AE) level II or lower (total AEs n = 589), similar rates in all randomized groups (P = .188) with no hospitalizations or interventions required. Only 4 laboratory confirmed COVID-19 cases occurred, with 2 in the placebo arm and one in each HCQ randomized arm.

Conclusions

This randomized placebo-controlled trial was able to demonstrate the safety of HCQ outpatient chemoprophylaxis in high-risk groups against COVID-19. Future studies of chemoprophylaxis for SARS-CoV-2 are needed as the epidemic continues worldwide.

Science's Response to CoVID-19

CoVID-19 is a multi-symptomatic disease which has made a global impact due to its ability to spread rapidly, and its relatively high mortality rate. Beyond the heroic efforts to develop vaccines, which we do not discuss herein, the response of scientists and clinicians to this complex problem has reflected the need to detect CoVID-19 rapidly, to diagnose patients likely to show adverse symptoms, and to treat severe and critical CoVID-19. Here we aim to encapsulate these varied and sometimes conflicting approaches and the resulting data in terms of chemistry and biology. In the process we highlight emerging concepts, and potential future applications that may arise out of this immense effort.

COVID-19 infection and rheumatoid arthritis: mutual outburst cytokines and remedies

In March 2020, COVID-19 infection caused by SARS-CoV-2 has been declared to be a global pandemic, where its complications, severity and mortality are reported to be due to the released inflammatory cytokines or the so-called cytokine storm. This is quite similar to that observed in the autoimmune and chronic inflammatory rheumatic disease, rheumatoid arthritis (RA). It was hypothesized that RA patients are at a higher risk of acquiring COVID-19; however, recent studies reported that they are not when compared to the rest of the population. In this review, we aim to highlight the mutual pathological features, cytokine profiles and risk factors between COVID-19 and RA. Also, many researchers are currently working to explore therapeutic agents that could aid in the eradication of COVID-19 infection. Due to the similarity between the inflammation status in COVID-19 and RA, many anti-rheumatic drugs such as hydroxychloroquine, tocilizumab, baricitinib and anakinra were proposed to be therapeutic modalities for COVID-19 infection.

COVID-19 Drugs Chloroquine and Hydroxychloroquine, but Not Azithromycin and Remdesivir, Block hERG Potassium Channels

Drug-induced long QT syndrome (LQTS) is an established cardiac side effect of a wide range of medications and represents a significant concern for drug safety. The rapidly and slowly activating delayed rectifier K⁺ currents, mediated by channels encoded by the human ether-a-go-go-related gene (hERG) and KCNQ1 + KCNE1, respectively, are two main currents responsible for ventricular repolarization. The common cause for drugs to induce LQTS is through impairing the hERG channel. For the recent emergence of COVID-19, caused by severe acute respiratory syndrome coronavirus 2, several drugs have been investigated as potential therapies; however, there are concerns about their QT prolongation risk. Here, we studied the effects of chloroquine, hydroxychloroquine, azithromycin, and remdesivir on hERG channels. Our results showed that although chloroquine acutely blocked hERG current (I_hERG), with an IC₅₀ of 3.0 µM, hydroxychloroquine acutely blocked I_hERG 8-fold less potently, with an IC₅₀ of 23.4 µM. Azithromycin and remdesivir did not acutely affect I_hERG When these drugs were added at 10 µM to the cell culture medium for 24 hours, remdesivir increased I_hERG by 2-fold, which was associated with an increased mature hERG channel expression. In addition, these four drugs did not acutely or chronically affect KCNQ1 + KCNE1 channels. Our data provide insight into COVID-19 drug-associated LQTS and cardiac safety concerns. SIGNIFICANCE STATEMENT: This work demonstrates that, among off-label potential COVID-19 treatment drugs chloroquine, hydroxychloroquine, azithromycin, and remdesivir, the former two drugs block hERG potassium channels, whereas the latter two drugs do not. All four drugs do not affect KCNQ1 + KCNE1. As hERG and KCNQ1 + KCNE1 are two main K⁺ channels responsible for ventricular repolarization, and most drugs that induce long QT syndrome (LQTS) do so by impairing hERG channels, these data provide insight into COVID-19 drug-associated LQTS and cardiac safety concerns.