After being diagnosed with COVID-19 earlier this week, President Donald Trump is currently on Remdesivir, an antiviral drug made by Gilead Sciences. The drug has not yet been approved by the Food and Drug Administration, but it was authorized for emergency use in May for treating hospitalized patients with COVID-19. The president received his first IV infusion of the drug on Friday night, and doctors say that he will undergo a five-day treatment of the drug. In addition to Remdesivir, President Trump has also been given an infusion of Regeneron Pharmaceutical Inc.’s REGN-COV2 drug, zinc, vitamin D, an acid reducer, melatonin and aspirin to treat his fever, fatigue, cough and other symptoms.

Remdesivir works by making it harder for the virus to replicate. COVID-19 can spread throughout the body so easily because it carries a special “proofreading” protein that catches replication errors, allowing the virus to replicate correctly. Remdesivir works by disrupting this process.

In response to taking the drug, White House physician, Dr. Sean Conley, said Trump is doing “very well.”