Essential Science: Round-up of COVID-19 drug developments
For this week's Essential science column, we delve into the latest research on the quest to develop drugs to help combat COVID-19 symptoms or to eliminate the novel SARS-CoV-2 coronavirus itself.by Tim Sandle
How are scientists seeking to combat the novel coronavirus through new medicines? The process is underway in many research laboratories. Answers will not be immediate and the process is challenging. This is partly due to the clinical spectrum of COVID-19 being wide, encompassing asymptomatic infection, a mild upper respiratory tract illness, and severe viral pneumonia with respiratory failure and even death.
We look at some current research examples.
Trials into hydroxychloroquine and azithromycin as COVID-19 treatment
Why President Trump is seemingly using himself as a human guinea pig, more scientifically thought out research is underway into whether the antimalarial hydroxychloroquine and the antibiotic azithromycin can provide any protective effect. This is taking the form of a double-blind clinical trial where both hydroxychloroquine and azithromycin treatment in patients with COVID-19 will be assessed. The U.S. National Institute of Allergy and Infectious Diseases (NIAID) is running the trial.
By double-blind this means there is an experimental group (who are given the medication) and a control group (who are given a placebo). With the experimental treatment group, members will be given 400mg of hydroxychloroquine twice on the first day and 200mg twice daily for an additional six days. In addition, group members will also take 500mg of azithromycin on the first day and 250mg daily for an additional four days.
Despite the U.S. research, the World Health Organization, WHO halted hydroxychloroquine trials for coronavirus amid safety fears on May 25, 2020. The trial was stopped, according to The Guardian, amid fears that the drug could raise risk of death and heart problems.
Resupposing other drugs
The use of hydroychloroquine, developed as an antimalarial, against the SARS-CoV-2 virus, is what is referred to as 'resupposing' - using a drug developed specifically against one disease to combat another, against a disease that it was not originally designed for. Other similar examinations are underway into broad-spectrum antiviral agents, which are being examined as good drug repurposing candidates. Such drugs generally aim to block viral replicative mechanisms.
Examples of drugs being examined include Umifenovir, which is classed as a membrane fusion inhibitor protecting cells from viral entry; lopinavir/ritonavir which attacks viral protease; and remdesivir, a viral RNA-dependent RNA polymerase inhibitor.
Scientists based at Utrecht University have provided data showing how a fully human monoclonal antibody, which is capable of preventing SARS-CoV-2 infection cells in vitro. This new research has built on previous work targeting SARS-CoV, which emerged in the early 2000s. The antibody binds to a conserved domain and further work is underway.
In related research, University of Texas at Austin successfully combined two copies of a llama antibody, which binds to the spike-S protein on the coronavirus. Llamas were used since they produce two types of antibody one of which is similar to human antibodies.
This article is part of Digital Journal's regular Essential Science columns. Each week Tim Sandle explores a topical and important science subject.
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