Casirivimab / Imdevimab Dosage

Medically reviewed by Drugs.com. Last updated on Apr 8, 2024.

Usual Adult Dose for COVID-19

For investigational use only

At least 40 kg:

• IV infusion: Casirivimab 600 mg and imdevimab 600 mg administered together as a single IV infusion
• Subcutaneous injection: Casirivimab 600 mg and imdevimab 600 mg subcutaneously

Comments:

• The US FDA issued an Emergency Use Authorization (EUA) to allow the emergency use of the unapproved product, casirivimab and imdevimab (co-formulated product and supplied as individual vials to be administered together), for the treatment of mild to moderate coronavirus disease 2019 (COVID-19) in patients with positive results of direct severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral testing who are at high risk for progression to severe COVID-19, including hospitalization or death; this product is not approved by the US FDA for this use.
• January 24, 2022: Due to the high frequency of the Omicron variant, this product is not currently authorized in any US region; therefore, this product may not be administered for treatment of COVID-19 under the EUA until further notice by the US FDA.
• Limitations of Authorized Use:
• This product is not authorized for treatment of mild to moderate COVID-19 in geographic regions where infection is likely due to nonsusceptible SARS-CoV-2 variant based on available information such as variant susceptibility to this product and regional variant frequency.
• This product is not authorized for use in patients who are hospitalized due to COVID-19, OR who require oxygen therapy due to COVID-19, OR who require an increase in baseline oxygen flow rate due to COVID-19 in those on chronic oxygen therapy due to underlying non-COVID-19 related comorbidity.
• Monoclonal antibodies (such as casirivimab and imdevimab) may be associated with worse clinical outcomes when administered to hospitalized patients with COVID-19 who require high flow oxygen or mechanical ventilation.
• The optimal dosing regimen has not been established for treatment of COVID-19; the recommended dosing regimen may be updated as clinical trial data become available.
• IV infusion is strongly recommended; subcutaneous injection is an alternative administration route when IV infusion is not feasible and would lead to delay in treatment.
• Casirivimab and imdevimab should be administered together as soon as possible after positive SARS-CoV-2 viral test and within 10 days of symptom onset.
• No dose adjustment recommended in pregnant or lactating patients.
• For additional information: https://www.fda.gov/emergency-preparedness-and-response/mcm-legal-regulatory-and-policy-framework/emergency-use-authorization#coviddrugs

Use: For the treatment of mild to moderate COVID-19 in patients with positive results of direct SARS-CoV-2 viral testing who are at high risk for progression to severe COVID-19, including hospitalization or death

Usual Adult Dose for Postexposure Prophylaxis

For investigational use only

At Least 40 kg:
Single Dose:

• IV infusion: Casirivimab 600 mg and imdevimab 600 mg administered together as a single IV infusion
• Subcutaneous injection: Casirivimab 600 mg and imdevimab 600 mg subcutaneously

Repeat Dosing:

• IV infusion:
• Initial dose: Casirivimab 600 mg and imdevimab 600 mg administered together as a single IV infusion
• Subsequent doses: Casirivimab 300 mg and imdevimab 300 mg administered together as a single IV infusion every 4 weeks for the duration of ongoing exposure
• Subcutaneous injection:
• Initial dose: Casirivimab 600 mg and imdevimab 600 mg subcutaneously
• Subsequent doses: Casirivimab 300 mg and imdevimab 300 mg subcutaneously every 4 weeks for the duration of ongoing exposure

Comments:

• The US FDA issued an EUA to allow the emergency use of the unapproved product, casirivimab and imdevimab (co-formulated product and supplied as individual vials to be administered together), for postexposure prophylaxis of COVID-19 in individuals who are at high risk for progression to severe COVID-19, including hospitalization or death, and are: not fully vaccinated OR who are not expected to mount an adequate immune response to complete SARS-CoV-2 vaccination AND have been exposed to someone infected with SARS-CoV-2 consistent with close contact criteria per US CDC OR who are at high risk of exposure to someone infected with SARS-CoV-2 due to occurrence of SARS-CoV-2 infection in others in the same institutional setting; this product is not approved by the US FDA for this use.
• January 24, 2022: Due to the high frequency of the Omicron variant, this product is not currently authorized in any US region; therefore, this product may not be administered for postexposure prevention of COVID-19 under the EUA until further notice by the US FDA.
• Limitations of Authorized Use:
• This product is not authorized for postexposure prophylaxis of COVID-19 in geographic regions where exposure is likely to have been to a nonsusceptible SARS-CoV-2 variant, based on available information including variant susceptibility to this product and regional variant frequency.
• Postexposure prophylaxis with this product is not a substitute for vaccination against COVID-19.
• This product is not authorized for preexposure prophylaxis for prevention of COVID-19.
• Either IV infusion or subcutaneous injection can be used.
• Casirivimab and imdevimab should be administered together as soon as possible after exposure to SARS-CoV-2.
• Repeat dosing may be appropriate for individuals with ongoing exposure to SARS-CoV-2 for longer than 4 weeks and who are not expected to mount an adequate immune response to complete SARS-CoV-2 vaccination.
• No dose adjustment recommended in pregnant or lactating patients.
• The optimal dosing regimen has not been established for treatment of COVID-19; the recommended dosing regimen may be updated as clinical trial data become available.
• Individuals are considered fully vaccinated 2 weeks after their second vaccine dose in a 2-dose series, or 2 weeks after a single-dose vaccine. For additional information: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated.html#vaccinated
• For additional information regarding individuals with immunocompromising conditions: https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/fully-vaccinated-people.html
• Close contact with an infected individual is defined as: being within 6 feet for at least 15 minutes (total), providing care at home to someone who is sick, having direct physical contact with the person (e.g., hugging, kissing), sharing eating/drinking utensils, or being exposed to respiratory droplets from an infected person (e.g., sneezing, coughing). For additional information: https://www.cdc.gov/coronavirus/2019-ncov/if-you-are-sick/quarantine.html
• For additional information: https://www.fda.gov/emergency-preparedness-and-response/mcm-legal-regulatory-and-policy-framework/emergency-use-authorization#coviddrugs

Use: For the postexposure prophylaxis of COVID-19 in individuals who are at high risk for progression to severe COVID-19, including hospitalization or death, and are:

• not fully vaccinated OR who are not expected to mount an adequate immune response to complete SARS-CoV-2 vaccination (e.g., individuals with immunocompromising conditions including those taking immunosuppressive agents) AND
• have been exposed to someone infected with SARS-CoV-2 consistent with close contact criteria per US CDC OR
• who are at high risk of exposure to someone infected with SARS-CoV-2 due to occurrence of SARS-CoV-2 infection in others in the same institutional setting (e.g., nursing homes, prisons)

Usual Pediatric Dose for COVID-19

For investigational use only

12 years or older, weighing at least 40 kg:

• IV infusion: Casirivimab 600 mg and imdevimab 600 mg administered together as a single IV infusion
• Subcutaneous injection: Casirivimab 600 mg and imdevimab 600 mg subcutaneously

Comments:

• The US FDA issued an EUA to allow the emergency use of the unapproved product, casirivimab and imdevimab (co-formulated product and supplied as individual vials to be administered together), for the treatment of mild to moderate COVID-19 in patients with positive results of direct SARS-CoV-2 viral testing who are at high risk for progression to severe COVID-19, including hospitalization or death; this product is not approved by the US FDA for this use.
• January 24, 2022: Due to the high frequency of the Omicron variant, this product is not currently authorized in any US region; therefore, this product may not be administered for treatment of COVID-19 under the EUA until further notice by the US FDA.
• Limitations of Authorized Use:
• This product is not authorized for treatment of mild to moderate COVID-19 in geographic regions where infection is likely due to nonsusceptible SARS-CoV-2 variant based on available information such as variant susceptibility to this product and regional variant frequency.
• This product is not authorized for use in patients who are hospitalized due to COVID-19, OR who require oxygen therapy due to COVID-19, OR who require an increase in baseline oxygen flow rate due to COVID-19 in those on chronic oxygen therapy due to underlying non-COVID-19 related comorbidity.
• Monoclonal antibodies (such as casirivimab and imdevimab) may be associated with worse clinical outcomes when administered to hospitalized patients with COVID-19 who require high flow oxygen or mechanical ventilation.
• The optimal dosing regimen has not been established for treatment of COVID-19; the recommended dosing regimen may be updated as clinical trial data become available.
• IV infusion is strongly recommended; subcutaneous injection is an alternative administration route when IV infusion is not feasible and would lead to delay in treatment.
• Casirivimab and imdevimab should be administered together as soon as possible after positive SARS-CoV-2 viral test and within 10 days of symptom onset.
• No dose adjustment recommended in pregnant or lactating patients.
• For additional information: https://www.fda.gov/emergency-preparedness-and-response/mcm-legal-regulatory-and-policy-framework/emergency-use-authorization#coviddrugs

Use: For the treatment of mild to moderate COVID-19 in patients with positive results of direct SARS-CoV-2 viral testing who are at high risk for progression to severe COVID-19, including hospitalization or death

Usual Pediatric Dose for Postexposure Prophylaxis

For investigational use only

12 Years or Older, Weighing At Least 40 kg:
Single Dose:

• IV infusion: Casirivimab 600 mg and imdevimab 600 mg administered together as a single IV infusion
• Subcutaneous injection: Casirivimab 600 mg and imdevimab 600 mg subcutaneously

Repeat Dosing:

• IV infusion:
• Initial dose: Casirivimab 600 mg and imdevimab 600 mg administered together as a single IV infusion
• Subsequent doses: Casirivimab 300 mg and imdevimab 300 mg administered together as a single IV infusion every 4 weeks for the duration of ongoing exposure
• Subcutaneous injection:
• Initial dose: Casirivimab 600 mg and imdevimab 600 mg subcutaneously
• Subsequent doses: Casirivimab 300 mg and imdevimab 300 mg subcutaneously every 4 weeks for the duration of ongoing exposure

Comments:

• The US FDA issued an EUA to allow the emergency use of the unapproved product, casirivimab and imdevimab (co-formulated product and supplied as individual vials to be administered together), for postexposure prophylaxis of COVID-19 in individuals who are at high risk for progression to severe COVID-19, including hospitalization or death, and are: not fully vaccinated OR who are not expected to mount an adequate immune response to complete SARS-CoV-2 vaccination AND have been exposed to someone infected with SARS-CoV-2 consistent with close contact criteria per US CDC OR who are at high risk of exposure to someone infected with SARS-CoV-2 due to occurrence of SARS-CoV-2 infection in others in the same institutional setting; this product is not approved by the US FDA for this use.
• January 24, 2022: Due to the high frequency of the Omicron variant, this product is not currently authorized in any US region; therefore, this product may not be administered for postexposure prevention of COVID-19 under the EUA until further notice by the US FDA.
• Limitations of Authorized Use:
• This product is not authorized for postexposure prophylaxis of COVID-19 in geographic regions where exposure is likely to have been to a nonsusceptible SARS-CoV-2 variant, based on available information including variant susceptibility to this product and regional variant frequency.
• Postexposure prophylaxis with this product is not a substitute for vaccination against COVID-19.
• This product is not authorized for preexposure prophylaxis for prevention of COVID-19.
• Either IV infusion or subcutaneous injection can be used.
• Casirivimab and imdevimab should be administered together as soon as possible after exposure to SARS-CoV-2.
• Repeat dosing may be appropriate for individuals with ongoing exposure to SARS-CoV-2 for longer than 4 weeks and who are not expected to mount an adequate immune response to complete SARS-CoV-2 vaccination.
• No dose adjustment recommended in pregnant or lactating patients.
• The optimal dosing regimen has not been established for treatment of COVID-19; the recommended dosing regimen may be updated as clinical trial data become available.
• Individuals are considered fully vaccinated 2 weeks after their second vaccine dose in a 2-dose series, or 2 weeks after a single-dose vaccine. For additional information: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/fully-vaccinated.html#vaccinated
• For additional information regarding individuals with immunocompromising conditions: https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/fully-vaccinated-people.html
• Close contact with an infected individual is defined as: being within 6 feet for at least 15 minutes (total), providing care at home to someone who is sick, having direct physical contact with the person (e.g., hugging, kissing), sharing eating/drinking utensils, or being exposed to respiratory droplets from an infected person (e.g., sneezing, coughing). For additional information: https://www.cdc.gov/coronavirus/2019-ncov/if-you-are-sick/quarantine.html
• For additional information: https://www.fda.gov/emergency-preparedness-and-response/mcm-legal-regulatory-and-policy-framework/emergency-use-authorization#coviddrugs

Use: For the postexposure prophylaxis of COVID-19 in individuals who are at high risk for progression to severe COVID-19, including hospitalization or death, and are:

• not fully vaccinated OR who are not expected to mount an adequate immune response to complete SARS-CoV-2 vaccination (e.g., individuals with immunocompromising conditions including those taking immunosuppressive agents) AND
• have been exposed to someone infected with SARS-CoV-2 consistent with close contact criteria per US CDC OR
• who are at high risk of exposure to someone infected with SARS-CoV-2 due to occurrence of SARS-CoV-2 infection in others in the same institutional setting

Renal Dose Adjustments

Renal dysfunction: No adjustment recommended.

Liver Dose Adjustments

Data not available

Precautions

US BOXED WARNINGS:

• Treatment: This EUA is for the use of the unapproved product, casirivimab and imdevimab (co-formulated product and supplied as individual vials to be administered together), to treat mild to moderate COVID-19 in patients with positive results of direct SARS-CoV-2 viral testing who are at high risk for progression to severe COVID-19, including hospitalization or death.
• Postexposure Prophylaxis: This EUA is for the use of the unapproved product, casirivimab and imdevimab (co-formulated product and supplied as individual vials to be administered together), for postexposure prophylaxis of COVID-19 in individuals who are at high risk for progression to severe COVID-19, including hospitalization or death, and are: not fully vaccinated OR who are not expected to mount an adequate immune response to complete SARS-CoV-2 vaccination AND have been exposed to someone infected with SARS-CoV-2 consistent with close contact criteria per US CDC OR who are at high risk of exposure to someone infected with SARS-CoV-2 due to occurrence of SARS-CoV-2 infection in others in the same institutional setting.
• Available Dosage Forms: This product is available as (1) a single vial which contains 2 antibodies co-formulated in a 1:1 ratio of casirivimab and imdevimab OR (2) individual antibody solutions in separate vials, which may be supplied in separate cartons, or together in a single carton (a co-packaged carton), or in a dose pack.
• Routes of Administration: This product may be administered by IV infusion or subcutaneous injection.
• For treatment: IV infusion is strongly recommended; subcutaneous injection is an alternative administration route when IV infusion is not feasible and would lead to delay in treatment.
• For postexposure prophylaxis: Either IV infusion or subcutaneous injection can be used.
• This product may only be administered in settings in which health care providers have immediate access to medications to treat a severe infusion or hypersensitivity reaction (e.g., anaphylaxis) and the ability to activate the emergency medical system, as needed.
• Health care providers must submit a report on all medication errors and ALL SERIOUS ADVERSE EVENTS potentially related to this regimen; the Fact Sheet for Health Care Providers should be consulted regarding reporting requirements.
• The authorized dosage may be updated as additional clinical trial data become available.
• ClinicalTrials.gov should be consulted for information on clinical trials testing this product in COVID-19.

CONTRAINDICATIONS:
Previous severe hypersensitivity reactions (including anaphylaxis) to either active component or to any of the ingredients

Safety and efficacy have not been established in patients younger than 18 years; this product (casirivimab and imdevimab) is not recommended for use in pediatric patients weighing less than 40 kg or those younger than 12 years.

Dialysis

Data not available

Other Comments

January 24, 2022: Due to the high frequency of the Omicron variant, this product is not currently authorized in any US region; therefore, this product may not be administered for treatment or postexposure prevention of COVID-19 under the EUA until further notice by the US FDA.

Administration advice:

• For Treatment: The preferred route of administration is by IV infusion after dilution.
• IV infusion is strongly recommended; subcutaneous injection is an alternative administration route when IV infusion is not feasible and would lead to delay in treatment.
• For Postexposure Prophylaxis: Either IV infusion or subcutaneous injection can be used.

ADMINISTRATION BY IV INFUSION:

• Casirivimab and imdevimab infusion solution should be administered by a qualified health care professional.
• Administer casirivimab and imdevimab together (after dilution); administer the entire infusion solution in the bag via pump or gravity (infusion time according to the size of infusion bag used).
• Use a polyvinyl chloride (PVC), polyethylene (PE)-lined PVC, or polyurethane (PU) infusion set with an in-line or add-on 0.2-micron polyethersulfone (PES) filter.
• For casirivimab 600 mg and imdevimab 600 mg, minimum infusion time per size of prefilled 0.9% Sodium Chloride or 5% Dextrose infusion bag: at least 20 minutes for 50 mL infusion bag to ensure safe use (maximum infusion rate: 180 mL/hour); 21 minutes for 100 mL infusion bag (maximum infusion rate: 310 mL/hour); 31 minutes for 150 mL infusion bag (maximum infusion rate: 310 mL/hour); 50 minutes for 250 mL infusion bag (maximum infusion rate: 310 mL/hour)
• For casirivimab 300 mg and imdevimab 300 mg, minimum infusion time per size of prefilled 0.9% Sodium Chloride or 5% Dextrose infusion bag: at least 20 minutes for 50 mL infusion bag to ensure safe use (maximum infusion rate: 165 mL/hour); 20 minutes for 100 mL infusion bag (maximum infusion rate: 310 mL/hour); 30 minutes for 150 mL infusion bag (maximum infusion rate: 310 mL/hour); 49 minutes for 250 mL infusion bag (maximum infusion rate: 310 mL/hour)
• Due to potential overfill of prefilled saline bags, administer the entire infusion solution in the bag to avoid underdosage.
• Do not administer the prepared (diluted) infusion solution simultaneously with any other medication.
• After infusion is complete, flush the tubing with either 0.9% Sodium Chloride Injection, USP or 5% Dextrose Injection, USP to ensure the required dose has been delivered.
• Clinically monitor patients during administration and observe patients for at least 1 hour after infusion is complete.

ADMINISTRATION BY SUBCUTANEOUS INJECTION:

• Administer subcutaneous injections consecutively, each at a different injection site, into the thigh, back of the upper arm, or abdomen (except for 2 inches [5 cm] around the navel); avoid the waistline.
• Use different quadrants of the abdomen/upper thighs/back of the upper arms to space apart each subcutaneous injection; do not inject into tender, damaged, bruised, or scarred skin.
• Clinically monitor patients after injections and observe patients for at least 1 hour.

Storage requirements:

• Unopened vials: Store in refrigerator at 2C to 8C (36F to 46F) in original carton to protect from light; may store at room temperature (up to 25C [77F]) in original carton up to 30 days (discard if not used within 30 days); do not freeze, shake, or expose to direct light.
• Remove casirivimab and imdevimab vial(s) from refrigerated storage and allow to equilibrate to room temperature for about 20 minutes before preparation; do not expose to direct heat; do not shake the vials.
• Prepared (i.e., diluted) infusion solution (for IV infusion): Should administer immediately; if immediate administration is not possible, store in refrigerator between 2C to 8C (36F to 46F) for no more than 36 hours or at room temperature up to 25C (77F) for no more than 4 hours. If refrigerated, allow to equilibrate to room temperature for about 30 minutes before administration.
• Prepared syringes (for subcutaneous administration): Should administer immediately; if immediate administration is not possible, store in refrigerator between 2C to 8C (36F to 46F) for no more than 24 hours or at room temperature up to 25C (77F) for no more than 8 hours. If refrigerated, allow to equilibrate to room temperature for about 20 minutes before administration.

Reconstitution/preparation techniques:

• There are differences in the way the 2 formulations are prepared; the Fact Sheet for Health Care Providers should be consulted.
• Casirivimab and imdevimab co-formulated solution in a vial or casirivimab and imdevimab as individual antibody solutions in separate vials may be used to prepare more than 1 dose simultaneously as appropriate, either in IV bags or in syringes for subcutaneous injection.
• Under the EUA, a single-dose vial may be used to prepare more than 1 dose.

PREPARATION FOR IV INFUSION:

• Casirivimab and imdevimab solution for IV infusion should be prepared by a qualified health care professional.
• Casirivimab and imdevimab solution co-formulated in a vial and in individual vials (including co-packaged carton and dose pack) must be diluted with either 0.9% Sodium Chloride Injection, USP or 5% Dextrose Injection, USP (in the same infusion bag) before IV administration.
• If using 1 vial to prepare more than 1 infusion bag, then all infusion bags should be prepared at the same time.

PREPARATION FOR SUBCUTANEOUS INJECTION:

• Casirivimab and imdevimab should be prepared using the appropriate number of syringes; all syringes should be prepared at the same time using the co-formulated vial or the individual vials.

IV compatibility:

• Compatible: 0.9% Sodium Chloride Injection, USP; 5% Dextrose Injection, USP
• Compatibility with other IV solutions and medications is not known.

General:

• There are 2 different formulations of this product:
• Casirivimab and imdevimab co-formulated solution containing 2 antibodies in a 1:1 ratio in a vial.
• Casirivimab and imdevimab are available as individual antibody solutions in separate vials supplied as follows: individual vials in individual cartons, or together in a single carton (a co-packaged carton), or in a dose pack (which contains individual vials of casirivimab and imdevimab, configurations that may vary in vial size, strength, and appearance, and in configurations that include different number of cartons).
• The Fact Sheet for Health Care Providers should be consulted.
• The US FDA will monitor conditions to determine whether use in a geographic region is consistent with this scope of authorization, referring to available information, including information on variant susceptibility, and US CDC regional variant frequency data (https://covid.cdc.gov/covid-data-tracker/#variant-proportions).
• Criteria for Identifying High-Risk Individuals: The following medical conditions or other factors may place adults and pediatric patients (12 to 17 years of age and weighing at least 40 kg) at higher risk for progression to severe COVID-19:
• Older age (e.g., at least 65 years of age)
• Obesity or being overweight (e.g., adults with BMI greater than 25 kg/m2, or if 12 to 17 years of age, have BMI greater than or equal to the 85th percentile for their age and gender based on US CDC growth charts)
• Pregnancy
• Chronic kidney disease
• Diabetes
• Immunosuppressive disease or immunosuppressive therapy
• Cardiovascular disease (including congenital heart disease) or hypertension
• Chronic lung diseases (e.g., chronic obstructive pulmonary disease, asthma [moderate-to-severe], interstitial lung disease, cystic fibrosis, pulmonary hypertension)
• Sickle cell disease
• Neurodevelopmental disorders (e.g., cerebral palsy) or other conditions that confer medical complexity (e.g., genetic/metabolic syndromes, severe congenital anomalies)
• Having a medical-related technological dependence (e.g., tracheostomy, gastrostomy, positive pressure ventilation [not related to COVID-19])
• Other medical conditions or factors (e.g., race, ethnicity) may also place individual patients at high risk for progression to severe COVID-19 and authorization of this product under the EUA is not limited to the medical conditions or factors listed above; the US CDC website (https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html) should be consulted for additional information. The benefit-risk should be considered for each patient.
• The Fact Sheet for Health Care Providers should be consulted regarding approved available alternatives.

Patient advice:

• Read the Fact Sheet for Patients, Parents, and Caregivers.
• Continue to self-isolate and use infection control measures (e.g., wear mask, isolate, social distance, avoid sharing personal items, clean and disinfect "high touch" surfaces, frequent handwashing) according to US CDC guidelines.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer