United States President Donald Trump's physicians are administering one of the most important potential vaccines in the containment of COVID to help get rid of the disease.

He is not only being treated with Regeneron's dual-antibody vaccine, but he's also being given another experimental COVID antiviral called remdesivir – which medical experts have used to treat some cases of the virus – as he remains confined at the Walter Reed military hospital in Bethesda, Maryland.

Dr. Sean Conley, Trump's doctor, said the president is showing symptoms that include a mild fever, fatigue, congestion, and cough. In a memo he released on Friday, Conley said Trump is doing "very well."

Trump was administered with the first dose of remdesivir late Friday and will undergo a five-day course of the intravenous vaccine, Conley disclosed in a media briefing on Saturday. Remdesivir has been given the green light by the U.S. Food and Drug Administration under its emergency use declaration (EUD) to treat COVID.

Remdesivir costs around $520 a vial, based on the price announced by its developer, Gilead Sciences, in June this year, and $390 per shot for patients covered by government health insurance.

Gilead Sciences originally produced the vaccine in 2009 as an antiviral against hepatitis C infections. Since then, health authorities have tried using remdesivir against other diseases like the Ebola and now the novel coronavirus.

Remdesivir works by cutting the volume of the disease in the body. Based on clinical test results released in May, the vaccine lowered patients' hospital stays by around four days, from two weeks to a median of 11 days.

Unlike hydroxychloroquine, the vaccine promoted by Trump earlier in the health crisis as a potential treatment for coronavirus, remdesivir has been less questionable.

Based on research involving 400 hospital patients, it was determined that almost 75 percent who have been given remdesivir had gotten better 14 days after therapy course, compared to 60 percent who were not given the vaccine.

The U.S. Health and Human Services Department disclosed it had secured half million treatment courses of remdesivir two months after the vaccine was approved for COVID-19 treatment.

According to Dr. Irwin Redlener, chief of the Pandemic Resource and Response Initiative at the Columbia University's National Center for Disaster Preparedness, remdesivir is not really a treatment in the sense it will cure patients. The vaccine "will just hopefully minimize the fatality rate" and reduce the course of the virus, NBC News quoted Redlener as saying.