The two authorized Covid-19 antibody treatments that may help keep high-risk patients out of the hospital are in such short supply that doctors are facing a daunting question as cases surge in the United States: Which patients should be first in line?
The antibody treatments must be given shortly after a patient tests positive, before severe symptoms begin. The hourlong IV infusions are considered to be among the more promising treatments for the disease.
But doses of the drugs, one made by Regeneron and the other by Eli Lilly, are extremely limited. Both companies received emergency use authorization from the Food and Drug Administration in recent weeks.
As many as 30,000 doses of Regeneron's treatment are expected to start being distributed Tuesday, Health and Human Services Secretary Alex Azar told reporters Monday, with an additional 50,000 doses available within one week. Eli Lilly has distributed about 120,000 doses.
That barely covers the number of new cases diagnosed in the U.S. each day — the seven-day average is 170,000 new cases a day.
"It is very challenging," Dr. Raymund Razonable, an infectious disease specialist with the Mayo Clinic in Rochester, Minnesota, said. "What we're doing is assessing who among our patients are most likely going to be at highest risk, and then considering them a priority."
The antibody treatments are not a cure for Covid-19; instead, they work to reduce the amount of virus in a person's body. If given early enough in the course of the disease, that could prevent patients from progressing to the point of hospitalization.
While doctors will be making difficult decisions about which patients will receive the antibody infusions, several high-profile patients have already touted the drugs in glowing terms. President Donald Trump received the Regeneron drug when he was hospitalized with Covid-19 in October and later praised it as a "cure." Dr. Ben Carson, secretary of the Department of Housing and Urban Development, received the treatment as well, and wrote on Facebook that he is "convinced" it saved his life. And former New Jersey Gov. Chris Christie received the Eli Lilly drug.
But Trump, Christie and Carson were all hospitalized with Covid-19, and therefore would not meet the criteria for the drugs' use as listed in their emergency authorizations from the FDA.
In fact, the FDA says the Regeneron and the Eli Lilly treatments should not be given to already hospitalized patients, or those on oxygen.
With some doses already available and more on the way, hospital systems nationwide are developing protocols for which patients will get the treatments.
Northwell Health in New York is focusing on the high risk of hospitalization component. High-risk patients are anyone considered obese — which, according to the Centers for Disease Control and Prevention, is more than 40 percent of U.S. adults — as well as those with chronic kidney disease, diabetes or any condition that compromises their immune system.
Another factor for health care systems is equitable distribution.
Razonable of the Mayo Clinic said his team of infectious disease experts determining which patients should be given the drug includes a group of lawyers "to make sure that we're allocating the drugs without any bias."
Dr. Tara Vijayan, an infectious disease expert at UCLA Health, is developing the medical center's distribution plan for the monoclonal antibodies.
"We absolutely have to do our part to make sure that it's delivered equitably and reach out to high-risk populations," Vijayan said.
"From an ethical distribution point, first come, first served, would be the way to go," said Dr. Cameron Wolfe, an infectious diseases expert and an associate professor of medicine at the Duke University School of Medicine.
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Beyond the question of "who" is "where."
Complicating matters is that the Eli Lilly and the Regeneron treatments are given by IV infusion, soon after patients test positive. That means patients must go to a specially equipped facility to receive the drug at a time when they're still infectious — eliminating the option of outpatient chemotherapy centers, for example, because cancer patients are highly immunocompromised.
While urgent care clinics and emergency departments are typically where a patient would be able to receive such treatment, "you don't want to gum them up at the busiest time of the year," Wolfe said.
And each infusion of the monoclonal antibodies takes one hour, with more time needed to screen patients upon arrival and then monitor them afterward in cases of any adverse reactions.
"The minimum amount of time for the entire process is going to be about three or four hours," Vijayan said.
"You can't just use any old clinic to run this. It has to be done in a place that can handle Covid," Wolfe said. "Those places are actually not as common as you might think."