How does Remdesivir work? | How it Works

The most common symptoms of COVID-19 are fever, dry cough, and general fatigue. However, some people are also asymptomatic. Serious symptoms of COVID-19 include shortness of breath, persistent chest pain, and a high fever. Patients with severe symptoms can be hospitalized and need oxygen to help them breathe. Due to the high number of cases of COVID-19 worldwide, human clinical trials have urgently tested potential treatments for this infectious disease. One such treatment is the drug Remdesivir (brand name Veklury), which has been approved or approved as a temporary COVID-19 treatment in about 50 countries around the world. How does remdesivir work?

How does remdesivir work?

Nucleic acids are a category of macromolecules that include single-stranded RNA and double-stranded DNA. RNA and DNA consist of repeating nucleotides – the building blocks of nucleic acids. RNA acts as a messenger by converting information stored in DNA into proteins that perform cellular functions in the body. Other responsibilities of RNA include coding, decoding, and regulating genes found in DNA. Coronaviruses, including SARS-CoV-2, which causes COVID-19, contain RNA as the only genetic material.

Remdesivir is an antiviral drug, which means that it disrupts virus replication. The viral replication process for the genetic material of SARS-CoV-2 requires an enzyme called RNA-dependent RNA polymerase (RdRp). Remdesivir converts in the body to a nucleoside analog called NTP, which replaces the naturally present nucleotide ATP in the new strand of RNA. This means that remdesivir interferes with the ability of the viral polymerase to produce new strands of viral RNA, thereby blocking the ability of the virus to multiply in an infected person's body.

Remdesivir is typically given intravenously to patients. The United States Food and Drug Administration (FDA) has stated that their use must be in a hospital or health care facility that can provide comparable care to a hospital for close monitoring.

Remdesivir clinical trials

Prior to the current novel coronavirus pandemic affecting numerous countries around the world, most studies have assessed the effectiveness of remdesivir against coronavirus strains such as MERS (Middle East Respiratory Syndrome) and SARS (Heavy Acute Respiratory Syndrome) examines animal models. Until the emergence of COVID-19 there was a lack of extensive research with human participants. Due to the lack of treatment options for severe symptoms requiring hospitalization, human clinical trials have been rapidly initiated to allow countries to investigate the safety, effectiveness, and quality of potential drug treatments for their citizens who have experienced severe symptoms of COVID-19 .

One such clinical study was recently published in the New England Journal of Medicine. It was a double-blind, randomized, placebo-controlled study – the gold standard – of intravenous administration of remdesivir for 10 days in 532 adults who were hospitalized with symptoms of lower respiratory infection due to COVID-19. Patients who received remdesivir had faster recoveries than those in the placebo group – defined as being discharged or not needing additional oxygen or medical care – and greater chances of improving their own condition.

According to the National Institutes of Health (NIH), it could not be concluded that the reduced overall mortality rate in the remdesivir group compared to the placebo group was not accidental. These results are similar to those of other studies that suggest that remdesivir administration may be beneficial in hospitalized patients. The benefits may be limited, however, and remdesivir may not be the only treatment, especially in severe cases.

In contrast, a study published by the World Health Organization concluded that remdesivir did not definitely reduce hospital mortality, the start of ventilation, or the length of hospital stay. The study included 405 hospitals in 30 countries where four antiviral drugs were tested on hospitalized COVID-19 patients. 2750 patients received remdesivir for 10 days.

Are there any risks?

As with most medications, people receiving remdesivir for treatment can experience side effects. The Food and Drug Administration outlined possible symptoms such as fever, elevated liver enzymes that indicate liver damage, and changes in blood pressure and heart rate.

Who can access remdesivir?

Many countries approve or approve the use of remdesivir to treat COVID-19 patients in hospital. Health Canada has issued an emergency clearance for Remdesivir, with a requirement that Gilead Science Canada – the drug manufacturing company – maintain the drug's safety, quality and effectiveness, as indicated by the initial government review of the drug. The drug can only be used in COVID-19 patients 12 years of age and older who weigh at least 40 kg and have been hospitalized and who have severe symptoms of COVID-19, including pneumonia. Recently, the Food and Drug Administration approved Remdesivir for use in hospitalized COVID-19 patients who meet the same age and weight requirements as Health Canada (see above). This makes Remdesivir the first drug approved for COVID-19 treatment in the United States. The approval of Remdesivir as a COVID-19 treatment is based on the results of three randomized, controlled clinical trials with a sample of hospitalized COVID-19 patients who experience mild to severe symptoms. One of these is the New England Journal of Medicine clinical study described above, according to the NIH.

References:

Amirian, E. S. & Levy, J. K. (2020). Up-to-date knowledge of the antiviral remdesivir (GS-5734) and GS-441524 as therapeutic options for coronaviruses. One Health, 100128.

Beigel, J.H., Tomashek, K.M., Dodd, L.E., Mehta, A.K., Zingman, B.S., Kalil, A.C., … & Finberg, R.W. (2020). Remdesivir for the treatment of Covid-19 – final report. The New England Journal of Medicine. doi: 10.1056 / NEJMoa2007764

Gilead. (2020). About Veklury. Retrieved from https://www.gilead.com/purpose/advancing-global-health/covid-19/about-veklury

Government of Canada. (2020). Remdesivir with Conditions Approved for the Treatment of Patients in Canada with Severe COVID-19 Symptoms. Retrieved from https://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2020/73621a-eng.php

National Health Institute. (2020). The final report confirms the benefits of remdesivir for COVID-19. Retrieved from https://www.nih.gov/news-events/nih-research-matters/final-report-confirms-remdesivir-benefits-covid-19

U.S. Food and Drug Administration. (2020). The FDA approves the first treatment for COVID-19. Retrieved from https://www.fda.gov/news-events/press-announcements/fda-approves-first-treatment-covid-19

Wang, Y., Zhang, D., Du, G., Du, R., Zhao, J., Jin, Y., … & Hu, Y. (2020). Remdesivir in Adults With Severe COVID-19: A Randomized, Double-Blind, Placebo-Controlled, Multi-Center Study. The Lancet, 395 (10236), 1569-1578. doi: 10.1016 / S0140-6736 (20) 31022-9

World health organization. (2020). Coronavirus disease (COVID-19). Retrieved from https://www.who.int/emergencies/diseases/novel-coronavirus-2019/question-and-answers-hub/q-a-detail/coronavirus-disease-covid-19

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