In the global fight against coronavirus, a powerful tool for protecting people against COVID-19 infection is the use of monoclonal antibodies. In February 2021, the U.S. Food and Drug Administration (FDA) issued an emergency use authorization (EUA) for monoclonal antibodies to treat mild to moderate COVID-19 in high-risk patients; in August 2021, the FDA issued an EUA for use for post-exposure prophylaxis (prevention) in high-risk patients
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But what are monoclonal antibodies, anyway? Infectious disease specialist Adarsh Bhimraj, MD, breaks down this very scientific-sounding term and explains how it’s helping prevent severe COVID-19 infections in high-risk patients.
What are monoclonal antibodies?
Monoclonal antibodies to fight COVID-19 are artificially manufactured antibodies designed to mimic your body’s natural antibodies.
To understand what this means, though, you first need to understand what antibodies are, generally.
Understanding natural antibodies
In the simplest of terms, Dr. Bhimraj says, “Antibodies are basically proteins that your body makes to fight a specific infection.”
When the human body is exposed to an infection, it begins to make certain proteins to fight that infection. Within 10 days of contracting COVID-19, your body starts to produce antibodies to fight the infection and to help you recover from it.
Once your body has experienced a particular infection, it keeps some antibodies in reserve so that if you’re exposed to the same infection again in the future, your body can start to fight it immediately.
“It’s very specific ammunition to fight particular infectious organisms,” Dr. Bhimraj says.
How monoclonal antibodies can help
Again, monoclonal antibodies are laboratory-made antibodies that do what your body’s natural antibodies do: fight off infection. There are several antibody combinations or “cocktails,” but the one that’s most commonly used right now is a combination of two drugs called bamlanivimab and etesevimab.
They work quickly and more powerfully, lending your body a hand in binding to what’s called the “spike protein” of the SARS-CoV-2 virus. That can prevent the virus from taking hold and causing serious infection.
“If somebody who does not have immunity to the SARS-CoV2 virus is exposed to a virus, monoclonal antibodies can block the virus and may prevent that person from actually having an infection,” Dr. Bhimraj says. “Or if somebody is already infected, the monoclonal antibodies can help keep the infection from worsening — as long as you get them early enough.”
So what’s the time frame? When it comes to receiving monoclonal antibodies to fight COVID-19, sooner is better. Once you’ve been exposed to the virus, you should receive monoclonal antibodies within 10 days for them to have the most impact.
Who is eligible for monoclonal antibodies?
Monoclonal antibody treatments are only available to certain patients.
“The FDA’s emergency use authorization doesn’t authorize the use of anti-SAR S CoV-2 monoclonal antibodies in everyone,” Dr. Bhimraj says. “Right now, it’s for people who have mild to moderate COVID-19 — not severe enough that they have to be admitted to the hospital for that reason or receive oxygen — and who also have high-risk factors.”
In order to be eligible to receive monoclonal antibodies for the treatment of COVID-19, you must meet the following criteria:
- Have tested positive for COVID-19, but have not been hospitalized for it.
- Are considered high-risk for developing severe COVID-19.
- Are age 12 or older and weigh at least 88 pounds.
You’re considered high-risk for developing severe COVID-19 if you have any of the following conditions:
- Age 65 or older.
- Chronic kidney disease.
- Cardiovascular disease.
- Chronic lung disease.
- Diabetes (Type 1 and Type 2).
- Neurodevelopmental disorders.
- Overweight (BMI higher than 25).
- Sickle cell disease.
- Weakened immune system.
“For many of these patients, receiving monoclonal antibodies early enough may prevent them from being admitted to the hospital,” Dr. Bhimraj says, “and studies show they’re effective.”
How monoclonal antibodies are administered
Monoclonal antibodies are only given intravenously (through an IV) or as a subcutaneous injection (as a shot). That means that in order to receive them, you need to be seen in a medical setting — which limits the overall availability of the treatment.
“It requires logistical support, in terms of nurses or other healthcare personnel, to administer it,” Dr. Bhimraj says. “In a pandemic setting, when infections are surging, that can consume scarce resources.”
How monoclonal antibodies compare to vaccination
If you’re not yet fully vaccinated when you receive monoclonal antibodies, you’ll have to wait 90 days to get the vaccine. Otherwise, the antibodies may impact the vaccine’s effectiveness.
But don’t think of monoclonal antibodies as an alternative to the COVID-19 vaccine. Getting vaccinated, Dr. Bhimraj reiterates, is still your body’s single best protection against contracting severe COVID-19.
“I can’t emphasize enough the importance of vaccines,” Dr. Bhimraj says. “They offer a much better kind of protection and a much more lasting protection that you can get with monoclonal antibodies. And there is actually much more efficacy and safety information on vaccines than we have on monoclonal antibodies, at this point. There’s more research to prove that vaccines are safe and effective.”