(CNN) President Donald Trump is now "in a race" against the coronavirus, the CEO of biotechnology company Regeneron said Friday after the drug maker provided a dose of its experimental antibody treatment to the President.
"He's in a race where his immune system is racing against the virus, and if the virus wins you can have dire consequences, obviously, and what our antibodies do is we make it a fair fight," Dr. Leonard Schleifer told CNN's Wolf Blitzer.
"He's in a higher risk group for a variety of reasons such as being older, and if we give our antibodies, we hope that we will give his immune system enough of a boost so that he can win this and make a complete recovery," Schleifer said.
Regeneron's experimental monoclonal antibody treatment is still in large-scale clinical trials, but is available for compassionate use, something the US Food and Drug and Administration has to approve on an individual basis.
"We've got a lot of data but we're still in the experimental phase, but when you're in the midst of a pandemic and you have people at risk, we think it makes sense to try these," Schleifer said.
Trump received a single 8 gram dose of Regeneron's dual antibody cocktail Friday and completed the infusion without incident, the President's physician, Dr. Sean Conley, said in a statement.
"In addition to the polyclonal antibodies, the President has been taking zinc, vitamin D, famotidine, melatonin and a daily aspirin," Conley said.
A single high-dose of Regeneron's antibody treatment should do the trick, Schleifer said.
"It's a large enough dose, so that it'll last for quite a long time, hopefully even beyond when he's made a complete recovery," he said. "We have evidence ready that these are long lasting in the body, as you'd expect with this type of therapy."
The cocktail includes two monoclonal antibodies—lab-engineered versions of immune system proteins targeted specifically against coronavirus.
"It's not all that complicated. We're just trying to mimic the natural immune system, which really isn't ready to go when the virus is already going," Schleifer said.
But an emergency medicine doctor at Brigham and Women's Hospital in Boston, Dr. Jeremy Faust, has been outspoken about giving the President an unapproved treatment.
"We don't give this medication out, not because you're not special enough to get it, (but) because we don't yet know," he said.
"We do a risk and benefit analysis of everything and if I can't tell my patient what the benefit is, there's no conversation to be had," Faust told CNN.
He also said giving the unproven treatment to Trump just doesn't look good.
"This is not ready for prime time and, quite frankly, it sends a message that they're scrambling," Faust said.
Other patients may seek the same treatment, he said.
"I can't look them in the eye and tell them that I know anything about it, in terms of its risks and benefits. That's a pretty bad precedent," Faust said.
But Schleifer says Regeneron is seeing promising results in its clinical trials.
And the former director of the US Centers for Disease Control and Prevention, Dr. Thomas Frieden, agreed.
Regeneron's experimental monoclonal antibody therapy to treat the coronavirus, although it's unproven, is "a promising treatment," said Frieden, the CEO of the health initiative Resolve to Save Lives.
"We don't know if it'll be helpful, but it's something that is not unreasonable to try," he said.
"There's a report that only fewer than 300 patients have received it. It seems to be most effective early in the disease, especially before patients make antibodies of their own."
Trump, who was admitted to Walter Reed National Military Hospital Friday evening, received the monoclonal antibody therapy earlier in the day, but Schleifer would not confirm whether first lady Melania Trump had also received the treatment.