Remdesivir:
Formally known as GS-5734, Remdesivir is a prodrug. It is a monophosphate that, through metabolism, forms an active analog (C-adenosine nucleoside triphosphate). Remdesivir is a broad-spectrum anti-viral. The agent was discovered during the trials that screened antimicrobials to find the drug with activity against RNA viruses. It is primarily used to treat Ebola patients in 2015. Now, it is in Phase -II trials to find out its activity against the hemorrhagic fever-induced by the Ebola virus.[41] Remdesivir is an antiviral known to decrease viral replication and hence reduce the viral load. It enters the nascent viral load and causes premature termination. The animal studies on MERS-CoV infected mice showed that the Remdesivir improved the pathological damage and decrease the viral load in the lungs and restore lung functions[41]. Remdesivir is under laboratory trials on cultured cells, animals, and non-human primate models. These trials demonstrated its value as an effective antiviral drug against coronaviruses. An intravenous loading dose of 200mg of remdesivir followed by 100mg for 5 to 10 days proved very useful in current clinical studies[41] Remdesivir is a potent drug for SARS-CoV-2 due to its broad-spectrum activity. It showed its potency in-vitro against several novel coronaviruses, including SARS-CoV-2 with EC50 values of 0.77 μM and an EC90 value of 1.76 μM.[20] Another recent study has shown that Remidesivir blocked viral infection with a half-maximal concentration of 0.77 μM against COVID-19[51].