Treatments effective, costly
Like the COVID vaccines given to nearly 214 million Americans, the antibody treatments taken by more than 1 million in the United States are highly effective and cause only rare (and usually minor) side effects.
Federal health officials say the infusions have helped keep the U.S. death toll -- now about 2,000 per day-- from soaring even higher, even as vaccine hesitancy persists, particularly in Southern states.
The FDA first authorized monoclonal antibody drugs in November 2020 -- just weeks before the vaccines were approved. But their popularity has soared as the Delta variant of the virus that causes COVID-19 has surged in recent months.
Clinical trials show that the drugs can cut COVID-related hospitalization or death in high-risk patients by as much as 70%-80%. They also can prevent infection in healthy people who have been exposed to an infected person, according to research published this month in The New England Journal of Medicine.
Monoclonal antibodies have been used for decades to treat cancer, autoimmune disorders, and other diseases, with the FDA approving nearly 100 such treatments since 1994.
The FDA has granted EUA approvals to four antibody treatments for COVID-19.
A two-antibody drug combination from Regeneron -- containing casirivimab and imdevimab -- has been shown to reduce the risk of hospitalization and death by 70% in people infected with COVID. Sotrovimab, made by GlaxoSmithKline and Vir, has had similar results.
The FDA approved a third treatment -- Eli Lilly’s combination of bamlanivimab and etesevimab -- in 2020, but the agency recommended against its use earlier this year after it proved ineffective against the Delta variant. The combination came back on the market in late August, but only in states where fewer than 5% of COVID infections are from strains, such as Delta, that are resistant to the treatment.
In June, the FDA authorized a fourth drug combination, Genentech’s tocilizumab, for people already hospitalized with COVID. But it is only moderately effective against the disease.
Lab-made monoclonal antibodies mimic the antibodies the body makes to fight viruses and illnesses. They work by targeting the spike protein on the surface of the virus. COVID vaccines work by priming the body’s immune system to recognize this very same spike protein and block it from entering your body’s cells, preventing infection.
Antibody treatments are given as an IV to treat an infection but can also be given as shots into the belly for people who have been exposed to the virus but have not yet been sickened by it, Dr. Huang says.
Timing is critical, he says, noting antibodies are most effective when given in the first few days after symptoms emerge.
Demands, concerns on the rise
Orders for monoclonal antibodies have skyrocketed in recent weeks -- to 168,000 doses per week in late August, up from 27,000 in July. The Biden administration, which has been covering the cost of the treatment for most patients, took over its distribution as well this week.
But experts foresee potential problems as patient demand increases.
Federal officials have already warned states of potential shortages ahead. Only about 2.4 million monoclonal antibody doses have been shipped nationally so far, less than half of which have been administered.
More supplies are on the way, with the federal government recently buying another 1.8 million doses for delivery in the months ahead. But for now, some hospitals are uncertain of supplies and are already struggling to meet the demand for the treatments.
Seven Southern states account for 70% of orders: Texas, Alabama, Florida, Mississippi, Tennessee, Georgia, and Louisiana. Those states have among the nation’s lowest vaccine rates and highest infection numbers.
Florida officials said the state’s latest weekly allotment left clinics 41,000 doses short of what they need. Tennessee has begun limiting treatments for unvaccinated patients to give priority to those most at risk of dying from COVID. And in Texas, elective surgeries have been postponed to make room for COVID-19 patients at some hospitals, as operating room nurses have been enlisted to give IVs.
Some strong proponents of monoclonal antibody treatments have been frustrated by Republican governors who are scrambling to push and deliver them, while opposing vaccine and mask mandates.
Raising vaccination rates, scientists say, would make the antibody treatments unnecessary in many cases.
Experts also note the drugs are far more costly than the vaccines -- with a price tag of about $2,100 for each IV, compared to $20-$40 for the shot.
“When you’re talking about just the cost to society as a whole -- turning down a [vaccine] that costs a couple dozen dollars for therapies that cost thousands of dollars -- it just doesn’t make any sense,” says Dr. Huang.
“And the tragedy is that a lot of these infections right now are preventable. It’s not like the pre-vaccine days, when we didn’t have anything better. And for these people, it’s just hard to justify that line of thinking. And so, the challenge is changing people’s minds. And that’s really been the difficult thing.”
In addition, the treatments take 90 minutes to administer, taxing health care workers in hard-hit states that have been slammed by the influx of patients.
Beyond these issues, Dr. Huang cites other public health costs of people choosing treatment over vaccination. The vaccine protects others because it limits transmission of the virus. By contrast, a single antibody IV helps only that patient and does not keep people from infecting others or becoming reinfected, requiring another IV.
“Getting the vaccine helps people beyond yourself; it helps the community, too,” he notes. “There’s just a strong argument for getting the vaccine. I obviously have a very biased opinion, but I would hope I have more of a scientific or expert opinion, but that doesn’t seem to matter these days.”