Currently, the most effective treatments available for Covid in the U.S. are monoclonal antibody drugs, which bind to the virus and stop it from infecting cells. But these treatments are typically administered intravenously by health care workers. This can pose logistical challenges both for hospitals, many of which are overburdened and short-staffed, and for patients, who may not be able to get to clinics or infusion sites.
The new antivirals are different. “You could potentially pick up your prescription and go home,” said Dr. Michelle Barron, the senior medical director of infection prevention and control for UCHealth, a health care system in Colorado.
The Merck and Pfizer treatments, which involve taking 30 or 40 pills over the course of five days, should be given early in the course of infection, while the virus is replicating quickly.
In clinical trials, which enrolled only unvaccinated people at high risk for serious disease, Merck’s regimen reduced the risk of hospitalization and death by about 30 percent when given within the first five days of symptoms, while Pfizer’s cut those risks by 89 percent when given within the first three days of symptoms.
Replicating these results in the real world will require people to act swiftly, perhaps at the first sign of the sniffle.
“It starts with the public education such that when people start to have mild symptoms, early in the course of their illness, they think, ‘This might be Covid-19, and I should get a test,’” said Alyssa Bilinski, an expert on public health policy at Brown University. “Then, of course, we have to have access to tests that have to ideally be affordable. Then people need to get their test results back and they need to get them back quickly.”
She added, “All of this needs to happen within three to five days.”
It is not yet clear whether officials will require patients to take a certain kind of Covid test before the drugs are prescribed. In Britain, which already authorized the Merck pill, regulators specified only “a positive SARS-COV-2 diagnostic test.”