Dr. Michael Saag cannot get enough monoclonal antibodies to treat Covid-19.
They're not for him, personally; he still has natural antibodies to the coronavirus since recovering from the illness this past March.
But Saag, an infectious disease physician at the University of Alabama at Birmingham, said he would take the monoclonal antibodies — made in a lab to mirror the body's natural immune response to the virus — "in a heartbeat" if he were to be infected a second time.
"Monoclonal antibody products are a godsend to those patients who are eligible and are seen by us early in the course of illness," Saag said. "The earlier, the better."
Unlike the antiviral drug remdesivir and the steroid dexamethasone — both of which are given to patients hospitalized with Covid-19 — monoclonal antibodies are the only therapy authorized by the Food and Drug Administration so far that is meant to prevent patients from being hospitalized in the first place. The FDA has granted emergency use authorization to two drugmakers — Eli Lilly and Regeneron — for their monoclonal antibody products.
But many doses sit untouched at health care facilities across the country, with providers reluctant to them.
"A lot of us in infectious disease aren't sure that the monoclonal antibodies are worth the effort," said Dr. Christopher Ohl, a professor of infectious diseases at Wake Forest School of Medicine in Winston-Salem, North Carolina.
Some doctors on the front lines of treating Covid-19 patients have actually declined their allotments of the treatment, citing lack of evidence it really works.
"This is not something that's ready for prime time," said Dr. Pieter Cohen, an associate professor at Harvard Medical School and physician with the Cambridge Health Alliance Respiratory Clinic near Boston.
In fact, the Infectious Diseases Society of America, which helps guide clinicians, recommends against routine use of monoclonal antibodies, citing insufficient proof they work. The National Institutes of Health treatment guidelines also indicate there is not enough data to recommend their use.
There is some early evidence that monoclonal antibodies can reduce the amount of virus in a person's system, referred to as viral load. Last week, drugmaker Regeneron published in the New England Journal of Medicine preliminary findings on 275 patients showing such a reduction, "with a greater effect in patients whose immune response had not yet been initiated or who had a high viral load at baseline."
Cohen acknowledged the findings, but added, "We have no idea what viral load means in terms of outcomes for patients with Covid." That is, will reducing the amount of virus in a person's body change the course of their illness?
President Donald Trump received the monoclonal antibodies made by Regeneron when he was hospitalized with Covid-19 and later claimed they were a "cure" — though it's impossible to pinpoint precisely how much they helped amid the variety of treatments he received.
Meanwhile, Operation Warp Speed officials have all but begged physicians to use available doses of the monoclonal antibodies.
Moncef Slaoui, chief scientific adviser for Operation Warp Speed, said last week that the usage of monoclonal antibodies thus far is "disappointing." His data showed that between 5 and 20 percent of the nation's supply had been used.
"Many states do have product available," said Health and Human Services Secretary Alex Azar. "The best time to get those antibodies is not when you show up in the emergency room, but soon after being diagnosed with Covid."
Both Eli Lilly's and Regeneron's monoclonal antibodies are meant to treat Covid-19 patients who are also at high risk of developing complications that might lead to hospitalization. But they must be given in the first four to seven days of their illness.
Eli Lilly said its preliminary analysis of its monoclonal antibody appeared to show a reduction in hospitalizations or visits to an emergency department. Those Phase 2 results were published in the New England Journal of Medicine in late October.
The idea of keeping hospitalizations to a minimum is tantalizing, particularly as the nation continues to log astronomical numbers of cases. As of Dec. 18, more than 114,000 people were currently hospitalized with Covid-19, according to the Covid Tracking Project. That's the largest number of hospitalizations reported in the U.S. since the pandemic began.
But administering the drugs can be costly and complicated for providers. Monoclonal antibodies are given intravenously, in an hourlong infusion, with an entire appointment lasting about three to four hours.
And because eligible Covid-19 patients are highly contagious, they must be kept separated from other vulnerable patients in need of outpatient infusions, such as those receiving chemotherapy for cancer.
"You have to have a dedicated infusion center for a dedicated amount of time," Ohl, of Wake Forest, said. "There's not a lot of us rushing out to give this stuff."
We're swamped just trying to figure out how to make sure there's enough room for everyone who's sick with Covid to get proper care.
The treatments, Cohen said, "are not a good use of our health care resources right now. We're swamped just trying to figure out how to make sure there's enough room for everyone who's sick with Covid to get proper care."
"To carve out those kinds of resources for an experimental treatment is not what I would recommend," he added.
Other facilities, too, have cited logistical complications for the infusions, redirecting their monoclonal antibody supplies to larger institutions, such as Vanderbilt University Medical Center in Nashville, Tennessee.
Dr. Karen Bloch, an infectious disease physician at Vanderbilt, said her team has about 500 doses available. "We are actively reaching out to patients who meet high-risk criteria and trying to get them treated within the first seven days after onset of illness," she said.
Anecdotally, Bloch said patients who've received the monoclonal antibodies have had "fantastic responses."
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Saag, of the University of Alabama at Birmingham, said in his experience, the treatment "has performed very well, much better by far than anything else we have used."
Saag said a main problem hindering his use of the monoclonal antibodies is that most patients are either referred to him too late, after seven days of illness, or they don't meet criteria outlined in the FDA's emergency use authorization for the treatment: over age 65 or have significant underlying health problems.
Medicines authorized for emergency use must follow strict guidelines outlined in the EUA, as it's called, so doctors do not have the flexibility to try them in other groups.
All agree: Larger, more robust studies of monoclonal antibodies are needed. Some are already in full swing.
Dr. Raymund Razonable, a professor of medicine and principal investigator of monoclonal antibody studies at the Mayo Clinic in Rochester, Minnesota, has overseen more than 900 antibody infusions spread across Mayo's centers nationwide.
Razonable's research is not yet completed, but anecdotally, he and his colleagues have found that about 2.6 percent of high-risk patients who have received the monoclonal antibodies end up hospitalized, versus about 10 percent of such patients who don't receive the treatment.
"This is really important for us as an institution," Razonable said, "because we're seeing increasing numbers of hospitalizations, to the point that we are expanding several units in the hospital to accommodate Covid patients."
One key may be effective communication and education in the public. If people who test positive for Covid-19 are unaware they could qualify for monoclonal antibodies, they will not seek treatment until it's too late.
"You want to catch them before they are not really feeling that sick yet," Razonable said, acknowledging doctors have a narrow window of opportunity to use the treatment.
"If you catch them early, the hope is that it will not lead to hospitalization," he said. "If we can prevent that from happening, it's going to be useful."