At Memorial Hermann, we continue to make the latest, most innovative treatments available to people across the Greater Houston area in the fight against COVID-19.

Monoclonal antibody therapy is an investigative treatment that can help some of our most at-risk community members who test positive for COVID-19.

  • If administered to high-risk, COVID-positive patients in the early stages of the disease, it may reduce the likelihood of severe illness or hospitalization due to COVID-19.
  • If administered to COVID-negative patients who have immune compromise or are unable to receive a vaccine, it can create long-lasting protection against the virus.

The U.S. Food and Drug Administration (FDA) has issued an Emergency Use Authorization (EUA) for monoclonal antibody therapy to be used in treating certain high-risk or immunocompromised individuals. If you are at a high risk of developing severe symptoms from COVID-19 and recently tested positive, or if you are COVID-negative but are significantly immunocompromised or allergic to a COVID-19 vaccine, please read on to learn more about monoclonal antibody therapy and whether it is right for you.

What is Monoclonal Antibody Therapy?

Monoclonal antibody therapy (also called MCA therapy or mAb treatment) is a procedure for treating certain COVID-19 patients who are at a risk for developing more serious symptoms. The treatment delivers medicines containing antibodies directly into your bloodstream, allowing your body to immediately begin fighting SARS-CoV-2, the virus that causes COVID-19.

MCA therapies for COVID-19 have received an Emergency Use Authorization (EUA) from the FDA. Clinical trial results suggest these treatments may lead to milder cases in high-risk patients.

What Are Monoclonal Antibodies and How Do They Work?

While your body naturally makes antibodies to fight infection, it may not have antibodies designed to recognize a new virus like SARS-CoV-2. And while vaccines provide the information to help your body develop COVID-19 antibodies, the process takes a couple of weeks, making them useful for preventing the disease but not for treating an active case.

Monoclonal antibodies are created in a lab and can begin fighting COVID-19 right away because they are delivered via injection. Early evidence suggests these antibodies can reduce the amount (also called the viral load) of SARS-CoV-2 virus in your body, potentially leading to milder symptoms and a lower chance of hospitalization while you have COVID-19.

Who Can Receive MCA Therapy?

Memorial Hermann is currently administering MCA therapy as a treatment for active cases to certain high-risk COVID-positive individuals, and as a preventative measure to certain COVID-negative individuals who are immunocompromised or allergic to a COVID vaccine.

Please note, potential candidates with active COVID-19 cases will first be considered for treatment via oral antiviral medication (such as paxlovid). If a candidate is not able to receive the oral antiviral medication, they will be considered for MCA therapy.

To receive MCA therapy for an active COVID-19 case, you must:

  • Be 12 years of age or older and weigh more than 88 pounds
  • Have tested positive for COVID-19 with mild to moderate symptoms (not requiring hospital admission or oxygen therapy due to COVID-19)
  • Be at a high risk for developing more serious symptoms from COVID-19

Please note, referrals for this type of MCA therapy must be completed within seven days of symptom onset or a positive test, whichever came first. The drug must be administered within 7 days of symptom onset or positive test, whichever came first.

To receive MCA therapy as a preventative measure, you must:

  • Be 12 years or older and 88 lbs. or more
  • Be COVID-negative with no known recent exposure
  • Have significant immune compromise due to a medical condition or receipt of immunosuppressive medications or treatments OR have a COVID vaccine allergy.

Is MCA Therapy Safe?

While MCA therapy for COVID-19 is still being studied in clinical trials, it has received Emergency Use Authorization (EUA) from the FDA. Hundreds of thousands of people have received the infusions for COVID-19, and researchers continue to study the treatments for their safety and effectiveness.

What is Emergency Use Authorization?

An Emergency Use Authorization (EUA) is issued by the FDA during public health emergencies to allow the use of yet unapproved medical products, such as vaccines or medicines, to diagnose, treat or prevent serious or life-threatening diseases or serious conditions. But even during the pandemic, these EUA medicines must meet certain criteria, including the following:

  • Based on the scientific evidence available, it is reasonable to believe they may be effective for diagnosing, treating or preventing COVID-19 or a related serious or life-threatening disease or condition.
  • The known and potential benefits of these medicines outweigh their known and potential risks.
  • There are no adequate, approved and available alternatives.

Because the medicines used in COVID-19 MCA therapy meet these requirements, the FDA has issued a EUA for their use in treating mild to moderate cases in certain high-risk patients.

What Should I Tell My Health Care Provider Before I Receive the Infusions?

Be sure to tell your health care provider about all medical conditions, including the following:

  • Allergies
  • Severe allergic reactions to monoclonal antibody therapy in the past
  • COVID-19 vaccination status
  • Serious illnesses
  • Pregnancy or plans to become pregnant
  • Breastfeeding or plans to breastfeed
  • Medications, including prescription, over-the-counter, vitamins and herbal products

What if I Am Pregnant or Breastfeeding?

Because MCA therapy is a new procedure, there is little data on its effects on women who are pregnant or breastfeeding. If you are pregnant or breastfeeding, you should discuss your options and specific situation with your health care provider.

Are There Any Side Effects?

As MCA therapy is still being studied, there is not a complete list of side effects. However, it is known that some patients experience side effects after receiving monoclonal antibody treatment, such as allergic reactions during or after the infusion.

Immediately contact your health care provider or seek medical attention right away if you experience symptoms after therapy including fever, chills, muscle aches or sweating; nausea; headache; shortness of breath or wheezing; low or high blood pressure; rapid or slow heart rate; chest discomfort or pain; swelling in your throat and face; rashes, hives or itching; and feeling confused, faint, fatigued, dizzy or weak.

How Do I Sign Up for MCA Therapy?

To receive MCA therapy, you must have a referral from your health care provider. If you are eligible to receive the treatment, your health care provider will review information with you regarding the therapy and medicines used in it. If you agree to receive monoclonal antibody therapy after this review, your health care provider will note your consent and send your information to Memorial Hermann’s pharmacy department. For outpatient treatment, a pharmacy representative will contact you to schedule your MCA therapy.

To speak with a doctor about monoclonal antibody therapy and whether you are eligible, please contact your health care provider or schedule a Virtual Urgent Care visit.

How Is MCA Therapy Administered?

Infusions are given by injecting one or two medicines into a vein (intravenous injections) or into the tissue under your skin (subcutaneous injections). Your health care provider will determine the best way for you to receive the treatment.

What Should I Expect When I Have My Infusion?

Depending on the type of MCA therapy you receive, the infusion process may take up to 2 to 3 hours. Our medical staff will conduct a screening and then begin to administer the therapy, which can take up to an hour. Following your therapy, our medical staff will have you stay for an additional period of time to ensure you do not have any allergic reactions or other side effects immediately after the infusion.

What if I Experience Side Effects or Medical Issues?

After completing treatment, Memorial Hermann medical staff will monitor you for an additional period of time and will treat you for any side effects that you may experience during that time. If you experience side effects or medical issues at any time after leaving the hospital or urgent care clinic where you received the treatment, seek medical attention immediately or contact your health care provider right away. Click here to schedule a Virtual Urgent Care visit.

What Other Treatment Options Exist?

In addition to those used in MCA therapy, the FDA has allowed for the emergency use of other medicines used to treat COVID-19 that are not yet FDA-approved. Visit for information on these medicines, or you can ask your health care provider about clinical trials that might be right for you.

If your doctor determines you are eligible for MCA therapy, whether or not you receive it is up to you. If you decide not to undergo the therapy or stop it at any time, your standard medical care will not change.

If I Get MCA Therapy for an Active Case of COVID-19, Do I Still Have To Self-Isolate?

Yes. In the days immediately following your therapy, even if you begin to feel better, you still have COVID-19 and can transmit it to others. Please protect yourself and others by following isolation requirements after receiving monoclonal antibodies.

Can I Get the COVID-19 Vaccine After Being Treated?

If you are not prevented by vaccine allergies from doing so, you can get the COVID-19 vaccine after MCA treatment, but you should wait 90 days after your infusion to do so.

Where Can I Get More Information?

To learn more, ask your health care provider, contact your local or state public health department.


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