A research conducted by the University of Alberta scientists has discovered that the drug remdesivir likely targets the replication of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
This virus causes the coronavirus disease 2019 or COVID-19. Replication of SARS-CoV-2 depends on the viral RdRp or RNA-dependent RNA polymerase, which in turn, is attacked by the investigational nucleotide analog remdesivir.
The research is related to the study conducted by the same laboratory in February about how remdesivir works against the Middle East Respiratory Syndrome or MERS, which is another type of coronavirus.
The chairperson of medical microbiology and immunology at the University of Alberta, Matthias Götte, says the team was optimistic about seeing the same results of the drug against SARS-CoV-2. He also said that they had obtained almost identical results as they have achieved with MERS, which shows that remdesivir is an extremely potent inhibitor for polymerases of coronaviruses.
Götte and his team's research discusses in detail how this drug, which was developed in 2014 to fight the Ebola virus, works. He also compares the polymerase of the virus as the engine which is responsible for synthesizing its genome. Remdesivir targets the polymerase, which is the logical target to stop the virus from spreading, according to Götte.
The laboratory's work demonstrates how the drug tricks the virus by mimicking its building blocks. Götte explained that the polymerases of the coronaviruses are sloppy and easily fooled. The inhibitor from the medicine gets incorporated several times, and the virus loses its capacity to replicate.
Götte also said that the evidence garnered from his group, along with other published studies, means that the drug can be categorized as a "direct-acting antiviral" against SARS-CoV-2. This discovery of remdesivir's direct action reinforces the potential of clinical trials for the drug in COVID-19 positive patients.
These ongoing clinical trials involve analysis of data from 53 patients. Twenty-two patients were in the United States, 22 in Europe or Canada, and 9 in Japan. The compassionate administration of the drug to severe COVID-19 patients has resulted in clinical improvement in 36 of 53 patients or 68 percent. The researchers recommend ongoing randomized placebo-controlled clinical trials to measure the efficacy of remdesivir therapy.
Götte expressed that the next step for his lab is to use their tools to evaluate other promising antivirals. He is also very hopeful that with the exceptional amount of research and high-level of cooperation worldwide among researchers, one or more effective treatments for COVID-19 will be discovered.
Remdesivir is also one of the drugs being accelerated by the World Health Organization (WHO) into clinical trials, comparing multiple potential treatments for hospitalized patients with COVID-19 in several countries. Results from pivotal clinical trials are expected the earliest from April to May.
Götte has also expressed that antivirals discovered during the height of the SARS outbreak in 2003, which might have had the potential to fight COVID-19, were never realized into widely available treatments, mainly because of the massive cost of developing new drugs.