Monoclonal Antibody Treatment: What is It & How Does it Work?

If you (or someone you know) has tested positive for COVID-19, one of the first questions you may have is, "What can be done to reduce the risk of getting sicker?"

Fortunately, there is good news: treatments are now available that can reduce that risk. Depending on your age, health history, and how long you've had symptoms of COVID-19, you may qualify for a promising form of treatment for the disease called monoclonal antibody (mAb) treatment.

mAb treatment may help people who:

  • Have a positive COVID-19 test, and had symptoms for 10 days or less
  • Are at high risk of getting more serious symptoms


What Are Monoclonal Antibodies?

Antibodies are proteins made by your body's immune system that fight off infections, including infections caused by viruses. Your body can remember how to make antibodies if you are exposed to the same germ again.

Mononclonal antibodies are just like your body's antibodies but are selected for their strong ability to resist the virus. They are produced like a medication and help your body fight illness. In 2020, the Food and Drug Administration authorized several different monoclonal antibodies to treat COVID-19.

To date, monoclonal antibodies are among the most promising treatments for mild to moderate symptoms of COVID-19.


What is the difference between monoclonal antibodies and a vaccine?

There are several differences. Vaccines train your immune system to protect you from specific germs by creating germ-fighting antibodies, while monoclonal antibodies provide your body with ready-made, germ-fighting antibodies if your immune system has not made enough of its own antibodies yet. They differ in what they do, how long they take to work, and how long they provide protection.

Vaccines can:

  • prevent new infections
  • provide long-term protection

Vaccines cannot:

  • treat existing infections
  • provide immediate protection to a person exposed to COVID-19

Monoclonal antibodies can:

  • treat existing infections
  • provide immediate protection to a person exposed to COVID-19


How does monoclonal antibody treatment work?

After entering your body, monoclonal antibodies look for and attach to the spike protein that sticks out of the coronavirus that causes COVID-19. When monoclonal antibodies attach to the spike protein, they can block the virus's ability to enter cells — and slow down the infection.


How effective are monoclonal antibodies?

According to a study from the New England Journal of Medicine, early clinical data show that monoclonal antibodies can successfully reduce COVID-19 hospitalization rates. Clinical trials have shown that these treatments can dramatically decrease hospitalizations and emergency department visits. They can also reduce the amount of virus found in an infected person's blood.

Health officials continue to monitor the safety and effectiveness of the treatments, and clinical trials are ongoing. It isn't yet known if monoclonal antibodies protect against future COVID-19 infections.


Who is eligible for monoclonal antibody treatment?

Anyone who tested positive for COVID-19, has had symptoms for 10 days or less, and one of the following:

  • At least 12 years old
  • Being overweight (having a BMI of more than 25 kg/m2, or if age 12-17, have BMI above the 85th percentile for their age and gender) based on Centers for Disease Control and Prevention clinical growth charts
  • Currently pregnant
  • Have a medical condition, including:
    • Chronic kidney disease
    • Cardiovascular disease (congenital heart disease, hypertension)
    • Diabetes
    • Down syndrome
    • Dementia
    • Liver disease
    • Chronic lung disease
    • Sickle cell disease
    • Immunosuppressive disease or immunosuppressive treatment
    • Current or former smoker
    • History of stroke or cerebrovascular disease
    • Current or history of substance abuse
    • Neurodevelopmental disorders or other conditions
    • hat confer medical complexity
    • Medical-related technological dependence (e.g., tracheostomy, gastrostomy)

    They are also intended for those who are required to quarantine due to a COVID-19 exposure. Patients may be eligible if not fully vaccinated and fit the "high risk" criteria listed above.

    Note: Monoclonal antibody treatment needs to be given within 10 days of the start of symptoms.


    What to Expect During Monoclonal Antibody Treatment

    Initially, health care workers within a hospital setting administered monoclonal antibodies with a one-time intravenous (IV) infusion, which takes anywhere from 30 minutes to an hour. After receiving the IV, patients must wait at least one more hour so health care workers can watch for side effects or negative reactions.

    Earlier this month, the guidelines were updated to include treatment by subcutaneous injection (using a short needle to administer the antibodies just under the skin). This new treatment method can be performed in a non-hospital, outpatient medical setting, increasing the ease of access to patients and significantly decreasing the amount of time it takes to complete the treatment.


    Monoclonal Antibody Treatment: Frequently Asked Questions


    What are the side effects of monoclonal antibodies?

    As with any medication, side effects can vary. The most common reported side effects shown to date include:

    • Allergic reactions - standard symptoms which vary by individual (very rare)
    • Fever within 12 hours of the treatment lasting less than 12 hours (4% incidence)
    • Redness at the injection site (4% incidence)
    • Worsening symptoms after treatment


    Can I get a COVID-19 vaccine if I have had antibody treatment?

    People who have received a monoclonal antibody infusion for COVID-19 should not be vaccinated within 90 days of their infusion. These people are eligible when the monoclonal antibodies no longer affect the vaccine.


    Can I receive monoclonal antibodies treatment if I already received the COVID-19 vaccine?

    Yes. If you already received one or both doses of the vaccine and you are eligible, you can receive this treatment.


    What is the cost of monoclonal antibody treatment?

    Because the federal government has purchased a supply of monoclonal antibody treatments, there is no cost to the patient for the antibody product itself. However, it is possible there may be administration costs related to providing the infusion. Most patients will bear no costs for the administration of the antibody treatment. Additionally, Medicare fully covers the administration costs.

    Summit Medical Group now provides monoclonal antibody treatment at many of our clinics. To see if this treatment is available or right for you, call your provider's office today. For additional information regarding monoclonal antibody treatments, visit the National Institutes of Health website.