Information about monoclonal antibody therapy for health care providers

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COVID-19 monoclonal antibodies can help prevent severe illness for some people who get infected with COVID-19. The FDA has authorized these antibody treatments for emergency use. The treatments are available to people who have tested positive for COVID-19, have mild to moderate symptoms, and are at high risk of developing severe illness. Monoclonal antibodies are also available as post-exposure prophylaxis for COVID-19 for people who are not fully vaccinated (or who may not be fully protected after vaccination, such as people with immunocompromising conditions) and have been exposed to someone with COVID-19 and are at high risk of developing severe illness. They may also be used as a post-exposure prophylaxis for people who are at high risk of exposure to COVID-19, such as an unvaccinated resident in a nursing home where there is a COVID-19 outbreak.

Scientific studies show that high-risk COVID-19 patients treated with monoclonal antibodies were significantly less likely to get very sick and/or need to be hospitalized compared to patients who did not receive the treatment. Studies have also shown that being treated with monoclonal antibodies reduces the risk of getting COVID-19 if the patient has been exposed to a person with COVID-19.

Eligibility for monoclonal antibody treatment

Monoclonal antibody treatments are available for people who test positive for COVID-19 with an onset of symptoms within 10 days and are not hospitalized, but who are at high risk of developing severe COVID-19. 

The following medical conditions or other factors may place adults and pediatric patients (age 12-17 years and weighing at least 40 kg) at higher risk for severe COVID-19:

  • Older age (≥65 years of age). 
  • Obesity or being overweight (adults with BMI >25 kg/m2, or if age 12-17, have BMI ≥85th percentile for their age and gender based on CDC growth charts).
  • Pregnancy. 
  • Chronic kidney disease. 
  • Diabetes. 
  • Immunosuppressive disease or immunosuppressive treatment. 
  • Cardiovascular disease (including congenital heart disease) or hypertension. 
  • Chronic lung diseases (for example, chronic obstructive pulmonary disease, asthma [moderate-to-severe], interstitial lung disease, cystic fibrosis and pulmonary hypertension). 
  • Sickle cell disease. 
  • Neurodevelopmental disorders (for example, cerebral palsy) or other conditions that confer medical complexity (for example, genetic or metabolic syndromes and severe congenital anomalies). 
  • Having a medical-related technological dependence (for example, tracheostomy, gastrostomy, or positive pressure ventilation [not related to COVID-19]).

Other medical conditions or factors (for example, race or ethnicity) may place individual patients at high risk for severe COVID-19. Authorization of monoclonal antibody treatments under the EUAs is not limited to the medical conditions or factors listed above. For more information on medical conditions and factors associated with increased risk, see the CDC’s website. Health care providers should consider the benefit-risk ratio for individual patients.

Monoclonal antibody treatments are not indicated for use on patients who are hospitalized, on oxygen for COVID-19 treatment, or require an increase in baseline oxygen flow rate due to COVID-19.

Eligibility for post-exposure prophylaxis monoclonal antibody therapy

Bamlanivimab/etesevimab and REGEN-COV are approved to prevent COVID-19 after exposure in adults and pediatric patients (age 12-17 years and weighing at least 40 kg) who:

  • Are at high risk of developing severe illness; AND
  • Are not fully vaccinated OR are not expected to adequately respond to a COVID-19 vaccination (for example, people with immunocompromising conditions and those taking immunosuppressive medications); AND
  • Have been exposed to an individual infected with COVID-19 consistent with close contact criteria per the CDC (someone who has been within six feet of an infected person for a total of 15 minutes or more over a 24-hour period) OR are at high risk of exposure to an individual infected with COVID-19 because of occurrence of COVID-19 infection in other individuals in the same institutional setting.

CDPHE recommends that providers prioritize patients who have tested positive for COVID-19 and are at high risk for progression to severe illness. However, mAb therapies may also be used prophylactically for high-risk patients who have been exposed to COVID-19 or are at high risk of having been exposed.

Types of monoclonal antibody therapy

Monoclonal antibody therapy involves the use of one or a combination of monoclonal antibody products. The currently authorized treatments are bamlanivimab/etesevimab, REGEN-COV (casirivimab in combination with imdevimab), and sotrovimab. Bamlanivimab/etesevimab and REGEN-COV are also authorized to be used for post-exposure prophylaxis in people exposed to COVID-19. Due to resistance demonstrated by certain variants, bamlanivimab/etesevimab will remain available as long as variants resistant to it (B.1.351/Beta, P.1/Gamma, AY.1, AY.2, and B.1.621) comprise less than 5% of circulating variants. There is currently no concern for resistance to REGEN-COV or sotrovimab. Find Colorado variant data on the COVID-19 data dashboard.

These outpatient treatments are administered intravenously (IV) or subcutaneously (SQ). IV administration requires a single infusion administered over an hour or less. SQ administration involves four injections. Currently, only REGEN-COV is available for SQ administration. IV and SQ administration are followed by one hour of monitoring.

Offering monoclonal antibody therapy

CDPHE encourages medical providers to offer monoclonal antibody therapy in their offices. 
Health care providers interested in offering monoclonal antibody therapy can contact CDPHE ( for assistance registering as a monoclonal antibody site.

Once an enrolled provider, monoclonal antibody doses can be ordered and shipped to your office for administration either through IV infusion or through subcutaneous injection. If you are already offering COVID-19 testing, a positive antigen test in your clinic can be followed immediately with monoclonal antibody therapy.

Bamlanivimab/etesevimab, REGEN-COV, and sotrovimab are free of charge to requesting sites. Each week, CDPHE receives an allotment of these three products to distribute to administering sites in Colorado. To request these products, sites must fill out this Status of Supply REDCap form by 11:59 p.m. on Wednesday each week for delivery the following week.

Prescribing monoclonal antibody therapy for your patients

Consider providing this therapy in your office. Once an enrolled provider, monoclonal antibody doses can be ordered and shipped directly to your office for administration either through IV infusion or through subcutaneous injection. We encourage medical providers to offer this treatment in their offices; a positive antigen test in the clinician be followed immediately with monoclonal antibody therapy. Providers can also use the COVID-19 Monoclonal Antibody Connector tool to find a site for their patients to receive monoclonal antibodies. 
Use of the Connector Tool is not required for sites or referring providers (no provider referral is required for treatment); a limited number of sites have opted in to receive referrals through the system. The Connector Tool is meant to provide a list of nearby sites for treatment and to send these sites a notification of the patient’s eligibility for therapy. Every medical provider should learn of the treatment centers available nearby, their processes for scheduling patients for treatment, and if they prefer to have patient referrals entered in the Connector Tool.
The final page of the monoclonal antibody Connector Tool includes a list and map of current monoclonal antibody treatment administration sites that have asked to be listed in the connector tool. You and your patient can select the preferred location to receive treatment. The site will be notified of the selection and the patient can then contact the site to schedule treatment.
If the site selected is unable to accommodate your patient, you will need to select another location. When you have done so, you must notify the original site in order for the patient’s record to be transferred to the new treatment location.

Information on monoclonal antibody therapy and access to administration for all Coloradans can be found through the University of Colorado.