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Casirivimab and Imdevimab

Class: Monoclonal Antibodies
- SARS-CoV-2-specific Monoclonal Antibody

Medically reviewed by Drugs.com. Last updated on Dec 3, 2020.

Warning

Special Alerts:

The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are cautioned that a combined regimen of Casirivimab and Imdevimab is not an approved treatment for coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2, but rather, is being investigated for and is currently available under an FDA emergency use authorization (EUA) for the treatment of mild to moderate COVID-19 in certain outpatients. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to the information contained in the accompanying monograph, and specifically disclaims all such warranties. Readers of this information are advised that ASHP is not responsible for the continued currency of the information, for any errors or omissions, and/or for any consequences arising from the use of the information contained in the monograph in any and all practice settings. Readers are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.

Introduction

Antiviral; recombinant human IgG1 neutralizing monoclonal antibodies specific for SARS-CoV-2 virus; used in a combination regimen.1

Uses for Casirivimab and Imdevimab

Coronavirus Disease 2019 (COVID-19)

Being investigated for and has been used for treatment of COVID-19 caused by SARS-CoV-2.7 8 11 One of several SARS-CoV-2-specific monoclonal antibody regimens being evaluated for treatment of COVID-19.9

Although efficacy and safety for treatment of COVID-19 not definitely established, casirivimab and imdevimab are available under an FDA emergency use authorization (EUA) for treatment of mild to moderate COVID-19 in certain outpatients at high risk for progressing to severe COVID-19 and/or hospitalization.1 2

On November 21, 2020, FDA issued an EUA that permits use of casirivimab and imdevimab for treatment of mild to moderate COVID-19 in adults and pediatric patients ≥12 years of age weighing ≥40 kg with positive results of direct SARS-CoV-2 viral testing who are at high risk for progressing to severe COVID-19 and/or hospitalization.2 This EUA requires that the drugs be administered by a health care provider in an outpatient setting and administered together as a single IV infusion using the dosages recommended in the EUA.2 (See Dosage and Administration.)

FDA issued the EUA for casirivimab and imdevimab after concluding that emergency use of the drugs for treatment of COVID-19 met criteria for issuance of an EUA for the following reasons: SARS-CoV-2 can cause a serious or life-threatening disease or condition, including severe respiratory illness; based on the totality of scientific evidence available to FDA, it is reasonable to believe that casirivimab and imdevimab administered together may be effective in treating mild to moderate COVID-19 in adults and pediatric patients ≥12 years of age weighing ≥40 kg who have positive results of direct SARS-CoV-2 viral testing and are at high risk for progressing to severe COVID-19 and/or hospitalization and, when used under the conditions described in the EUA, known and potential benefits of the drugs outweigh known and potential risks; and there are no adequate, approved, and available alternatives to emergency use of casirivimab and imdevimab for treatment of COVID-19 in such patients.2

The EUA for casirivimab and imdevimab defines patients at high risk for progressing to severe COVID-19 and/or hospitalization as those who meet at least one of the following criteria: body mass index (BMI) ≥35, chronic kidney disease, diabetes mellitus, immunosuppressive disease, or immunosuppressive treatment; ≥65 years of age; ≥55 years of age with cardiovascular disease, hypertension, COPD, or other chronic respiratory disease; 12–17 years of age with BMI ≥85th percentile for their age and gender based on CDC growth charts, sickle cell disease, congenital or acquired heart disease, neurodevelopmental disorder such as cerebral palsy, medical-related technological dependence (such as tracheostomy, gastrostomy, or positive-pressure ventilation not related to COVID-19), or asthma, reactive airway disease, or other chronic respiratory disease that requires daily medication for control.1

Casirivimab and imdevimab are not authorized under the EUA for use in patients who are hospitalized due to COVID-19, require oxygen therapy due to COVID-19, or are on chronic oxygen therapy due to an underlying non-COVID-19-related comorbidity and require an increase in baseline oxygen flow rate due to COVID-19.1 2 Benefit not observed when used in patients hospitalized due to COVID-19; SARS-CoV-2-specific monoclonal antibodies, such as casirivimab and imdevimab, may be associated with worse clinical outcomes when administered to hospitalized COVID-19 patients requiring high-flow oxygen or mechanical ventilation.1 2

The EUA for casirivimab and imdevimab authorizes that distribution of the drugs will be controlled by the US government for use consistent with the terms and conditions of the EUA.2 (See Restricted Distribution under Preparations.)

To mitigate risks of these unapproved drugs, the EUA includes certain mandatory requirements (including providing information to the patient or parent/caregiver and ensuring that all medication errors and serious adverse events potentially attributable to the drugs are reported to FDA).1 2

Consult the casirivimab and imdevimab EUA letter of authorization,2 EUA fact sheet for health care providers,1 and EUA fact sheet for patients, parents, and caregivers3 for additional information.

Based on data available to date, NIH COVID-19 Treatment Guidelines Panel states that data are insufficient to recommend either for or against use of casirivimab and imdevimab for treatment of outpatients with mild to moderate COVID-19.14 The panel states casirivimab and imdevimab should not be considered the standard of care for treatment of COVID-19;14 more data needed to assess impact of casirivimab and imdevimab on course of the disease and identify patients most likely to benefit from the drugs.14

Casirivimab and Imdevimab Dosage and Administration

General

  • Must be administered to outpatients in a setting in which health care providers have immediate access to medications to treat a severe infusion reaction, such as anaphylaxis, and the ability to activate the emergency medical system (EMS) as necessary.1

  • Must clinically monitor patient during IV infusion of casirivimab and imdevimab and observe patient for at least 1 hour after completion of the infusion.1 (See Sensitivity and Infusion-related Reactions under Cautions.)

  • Advise patients treated with casirivimab and imdevimab to continue to self-isolate and use infection control measures (e.g., wear mask, isolate, socially distance, avoid sharing personal items, clean and disinfect “high touch” surfaces, wash hands frequently) according to CDC guidelines.1

  • Information for clinicians and infusion sites of care administering casirivimab and imdevimab to outpatients under the EUA, including recommendations for planning and implementation and considerations involving resources and equipment, may be available from the manufacturer12 or US Health and Human Services (HHS) Office of the Assistant Secretary for Preparedness and Response (ASPR).13

Administration

IV Administration

Administer casirivimab and imdevimab together only by IV infusion.1

For solution and drug compatibility information, see Compatibility under Stability.

After IV infusion is completed, flush infusion line with 0.9% sodium chloride injection.1

Dosage and Administration Precautions

Manufacturer alerted health care providers about risk of medication errors because of variations in casirivimab and imdevimab packaging and labeling.4

Casirivimab and imdevimab are packaged separately but must be combined and administered together after dilution as a single IV infusion.1 4 Consider several strategies to mitigate risk of a possible medication error, including storing casirivimab and imdevimab together in inventory, creating an alert in the electronic health record (EHR) system for health care providers that casirivimab and imdevimab must be used together, and ensuring that EHR systems always use casirivimab and imdevimab and only include an option for single IV infusion of the drugs after dilution.4

Although some cartons and vials of casirivimab and imdevimab may be labeled “for intravenous infusion or subcutaneous injection”,4 the drugs must be administered together only by IV infusion as specified in the EUA.1 4

Some cartons and vials of casirivimab and imdevimab may be labeled REGN10933 and REGN10987, respectively.1 4

Casirivimab and imdevimab may each be supplied as two different vial sizes (i.e., vials containing 1332 mg/11.1 mL or vials containing 300 mg/2.5 mL).1 4 Follow instructions for preparing the casirivimab and imdevimab solution for IV infusion (e.g., number of vials) to ensure correct dose.1 (See Table 1.)

Dilution

Casirivimab and imdevimab are each supplied as solution concentrates in separate vials; must dilute the drugs together in 0.9% sodium chloride injection prior to IV infusion.1

Remove appropriate number of vials of casirivimab solution concentrate (either four vials containing 300 mg/2.5 mL [120 mg/mL] or one vial containing 1332 mg/11.1 mL [120 mg/mL]) and appropriate number of vials of imdevimab solution concentrate (either four vials containing 300 mg/2.5 mL [120 mg/mL] or one vial containing 1332 mg/11.1 mL [120 mg/mL]) from refrigerated storage (see Storage under Stability) and allow to equilibrate to room temperature for approximately 20 minutes before preparing combined dilution for IV infusion.1

Casirivimab and imdevimab solution concentrates should each appear as clear to slightly opalescent and colorless to slightly yellow solutions; discard if solution concentrate contains particulates or is discolored.1

Dilute solution concentrates in a 250-mL prefilled IV infusion bag containing 0.9% sodium chloride injection.1 Prior to transferring the solution concentrates to the IV bag, withdraw 20 mL of 0.9% sodium chloride from the bag and discard.1 Using a separate syringe for each drug, withdraw a total of 10 mL of casirivimab solution concentrate and a total of 10 mL of imdevimab solution concentrate from their respective vial(s) and transfer into the IV bag containing 0.9% sodium chloride.1 (See Table 1.) Gently invert IV bag by hand approximately 10 times; do not shake.1

Table 1. Instructions for Combining and Diluting Casirivimab and Imdevimab in 0.9% Sodium Chloride for IV Infusion1

Recommended Dose of Casirivimab and Imdevimab

Total Volume to Withdraw from Vial(s) of Casirivimab Solution Concentrate Containing 120 mg/mL

Total Volume to Withdraw from Vial(s) of Imdevimab Solution Concentrate Containing 120 mg/mL

Final Dilution in 250-mL IV Bag Containing 0.9% Sodium Chloride

2.4 g (casirivimab 1.2 g and imdevimab 1.2 g)

Withdraw 10 mL from one vial containing 1332 mg/11.1 mL

Withdraw 10 mL from one vial containing 1332 mg/11.1 mL

Withdraw and discard 20 mL of 0.9% sodium chloride from the IV bag prior to adding 10 mL of casirivimab solution concentrate and 10 mL of imdevimab solution concentrate to provide the final combined dilution for IV infusion

or

or

Withdraw 10 mL total from four vials containing 300 mg/2.5 mL

Withdraw 10 mL total from four vials containing 300 mg/2.5 mL

Administer combined casirivimab and imdevimab solution immediately after dilution.1 If immediate administration not possible, may store combined diluted solution for up to 4 hours at room temperature (up to 25°C) or for up to 36 hours in a refrigerator (2–8°C), including infusion time.1 If combined diluted solution was refrigerated, allow it to equilibrate to room temperature for approximately 30 minutes prior to administration.1

Use a polyvinyl chloride (PVC), polyethylene (PE)-lined PVC, or polyurethane (PU) infusion set and a 0.2-µm polyethersulfone (PES) inline or add-on filter when administering the combined casirivimab and imdevimab solution.1

Casirivimab and imdevimab contain no preservatives;1 discard any unused solution concentrate remaining in vial(s) and discard any unused diluted solution of the drugs.1

Rate of Administration

Administer by IV infusion over at least 60 minutes via pump or gravity.1

Dosage

Optimal dosage regimen of casirivimab and imdevimab for treatment of COVID-19 not established.1 Dosage regimen recommended in the EUA may be updated as data from clinical trials become available.1

Pediatric Patients

Coronavirus Disease 2019† (COVID-19)
Outpatients with Mild to Moderate Disease†
IV

FDA EUA that permits use for treatment of mild to moderate disease (see Coronavirus Disease 2019 [COVID-19] under Uses) states that pediatric patients ≥12 years of age weighing ≥40 kg who are outpatients at high risk for progressing to severe COVID-19 and/or hospitalization should receive 1.2 g of casirivimab and 1.2 g of imdevimab administered together as a single IV infusion.1 Administer as soon as possible after positive viral test for SARS-CoV-2 and within 10 days of symptom onset.1

Adults

Coronavirus Disease 2019† (COVID-19)
Outpatients with Mild to Moderate Disease†
IV

FDA EUA that permits use for treatment of mild to moderate disease (see Coronavirus Disease 2019 [COVID-19] under Uses) states that adults who are outpatients at high risk for progressing to severe COVID-19 and/or hospitalization should receive 1.2 g of casirivimab and 1.2 g of imdevimab administered together as a single IV infusion.1 Administer as soon as possible after positive viral test for SARS-CoV-2 and within 10 days of symptom onset.1

Prescribing Limits

Pediatric Patients

Coronavirus Disease 2019† (COVID-19)
IV

Single dose.1

Adults

Coronavirus Disease 2019† (COVID-19)
IV

Single dose.1

Special Populations

Hepatic Impairment

Effect of hepatic impairment unknown.1

Renal Impairment

Dosage adjustment not needed.1

Cautions for Casirivimab and Imdevimab

Contraindications

  • None.1

Warnings/Precautions

Sensitivity and Infusion-related Reactions

Potential for serious hypersensitivity reactions, including anaphylaxis.1 At least one anaphylactic reaction reported in clinical trials; reaction began within 1 hour after completion of the IV infusion, required treatment with epinephrine, and resolved.1

Infusion-related reactions reported.1 Signs and symptoms of infusion-related reactions may include fever, chills, nausea, headache, bronchospasm, hypotension, angioedema, throat irritation, rash (including urticaria), pruritus, myalgia, or dizziness.1

If signs and symptoms of anaphylaxis or other clinically important hypersensitivity reaction occur, immediately discontinue casirivimab and imdevimab IV infusion and initiate appropriate medications and/or supportive care.1

If an infusion-related reaction occurs, slow or stop casirivimab and imdevimab IV infusion and initiate appropriate medications and/or supportive care.1

Limitations of Benefit and Potential for Risk in Patients with Severe COVID-19

Not authorized for use under the EUA in patients who are hospitalized due to COVID-19, require oxygen therapy due to COVID-19, or are on chronic oxygen therapy due to an underlying non-COVID-19-related comorbidity and require an increase in baseline oxygen flow rate due to COVID-19.1

Benefit not observed when used in patients hospitalized due to COVID-19.1 SARS-CoV-2-specific monoclonal antibodies, such as casirivimab and imdevimab, may be associated with worse clinical outcomes when administered to hospitalized COVID-19 patients requiring high-flow oxygen or mechanical ventilation.1

EUA Requirements for Patient Monitoring and Mandatory FDA MedWatch Reporting

Safety and efficacy not established.1 FDA issued an EUA that permits use of casirivimab and imdevimab for treatment of coronavirus disease 2019 (COVID-19) in certain adults and pediatric patients with mild to moderate COVID-19 in an outpatient setting via IV infusion using the dosages recommended in the EUA.1 (See Coronavirus Disease 2019 [COVID-19] under Uses.)

Only limited data available to date regarding adverse effects associated with use of casirivimab and imdevimab.1 Serious and unexpected adverse events may occur that have not been previously reported with the drugs.1

Completion of FDA MedWatch forms to report all medication errors and all serious adverse events potentially related to casirivimab and imdevimab is mandatory.1 Consult fact sheet for health care providers that is provided with the drugs and available at FDA website for requirements and instructions regarding reporting of adverse reactions and medication errors.1

Specific Populations

Pregnancy

Data insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes.1 Estimated background risk of major birth defects and miscarriage related to COVID-19 unknown.1

Use during pregnancy only if potential benefit outweighs potential risk for the woman and fetus.1 If used in pregnant women, dosage adjustment not recommended.1

NIH panel states do not withhold casirivimab and imdevimab from a pregnant woman who has a condition that poses a high risk of progression to severe COVID-19 if clinician thinks potential benefit of the drugs outweighs potential risk.14

Nonclinical reproductive toxicity studies not performed.1 In a tissue cross-reactivity study with casirivimab and imdevimab using human fetal tissues, no binding of clinical concern detected.1 Human IgG1 antibodies are known to cross the placenta; therefore, casirivimab and imdevimab have potential to be transferred from the pregnant woman to the developing fetus.1 Not known whether such potential placental transfer provides any treatment benefit or risk to the developing fetus.1

Lactation

Not known whether casirivimab and imdevimab distribute into human or animal milk, have effects on breast-fed infant, or affect milk production.1 Maternal IgG is known to be present in human milk.1

Consider the developmental and health benefits of breast-feeding along with the mother’s clinical need for casirivimab and imdevimab and any potential adverse effects on the breast-fed child from the drugs or from the underlying maternal condition.1 If used in lactating women, dosage adjustment not recommended.1 Women with COVID-19 who are breast-feeding should follow clinical guidelines to avoid exposing the infant to the virus.1

Pediatric Use

Safety and efficacy not assessed in pediatric patients.1

The EUA permits use for treatment of mild to moderate COVID-19 in certain pediatric patients ≥12 years of age weighing ≥40 kg (see Coronavirus Disease 2019 [COVID-19] under Uses).1 Not recommended in pediatric patients <12 years of age or weighing <40 kg.1

The EUA-recommended dosage regimen is expected to result in serum exposures of the drugs in patients ≥12 years of age weighing ≥40 kg that are comparable to those observed in adults since adults with similar body weight have been included in a clinical trial (NCT04425629; R10933-10987-COV-2067).1

Geriatric Use

Data from an ongoing trial evaluating casirivimab and imdevimab for treatment of mild to moderate COVID-19 in outpatients (NCT04425629; R10933-10987-COV-2067) indicated that 7% of the 799 randomized patients were ≥65 years of age and 2% were ≥75 years of age.1

Difference in pharmacokinetics of casirivimab and imdevimab in geriatric patients compared with younger patients unknown.1

Hepatic Impairment

Effect of hepatic impairment on pharmacokinetics of casirivimab and imdevimab unknown.1

Renal Impairment

Not expected to affect casirivimab and imdevimab exposures; drugs not eliminated by renal excretion.1

Common Adverse Effects

Data from an ongoing trial in outpatients with mild to moderate COVID-19 (NCT04425629; R10933-10987-COV-2067) indicate serious adverse events reported in 1.6% of patients treated with casirivimab and imdevimab 2.4 g (1.2 g of each drug), 0.8% of patients treated with casirivimab and imdevimab 8 g (4 g of each drug), and 2.3% of patients in placebo group.1 Grade 3 or 4 adverse events reported in those who received the 2.4-g dose included pneumonia, hyperglycemia, nausea, and vomiting; none of these events were considered related to the drugs.1

Interactions for Casirivimab and Imdevimab

Not metabolized by CYP isoenzymes and not renally excreted; interactions unlikely if used concomitantly with drugs that are substrates, inducers, or inhibitors of CYP isoenzymes or with drugs that are renally excreted.1

Casirivimab and Imdevimab Pharmacokinetics

Absorption

Pharmacokinetic profiles of casirivimab and imdevimab expected to be consistent with that of other IgG1 monoclonal antibodies.1

Flat dose-response relationship for efficacy identified based on viral load and clinical outcomes in a clinical trial evaluating casirivimab and imdevimab administered together at doses equal to or 3.33 times higher than the recommended doses in outpatients with mild to moderate COVID-19 (NCT04425629; R10933-10987-COV-2067).1

Distribution

Not known whether casirivimab and imdevimab distribute into human or animal milk.1

Elimination

Metabolism

Casirivimab and imdevimab not metabolized by CYP isoenzymes.1

Elimination Route

Casirivimab and imdevimab not eliminated by renal excretion.1

Dialysis not expected to affect pharmacokinetics of either drug.1

Special Populations

Renal impairment: Not expected to affect casirivimab and imdevimab exposures since monoclonal antibodies with molecular mass >69 kDa do not undergo renal elimination.1

Effects of hepatic impairment, sex, race, body weight, or disease severity on pharmacokinetics of the drugs unknown.1

Stability

Storage

Parenteral

Solution Concentrates for Injection, for IV Infusion

Casirivimab and imdevimab are each supplied as solution concentrates in separate vials.1

Vials containing casirivimab solution concentrate and vials containing imdevimab solution concentrate: Refrigerate (2–8°C); store in original cartons to protect from light.1 Do not freeze, shake, or expose to direct heat.1

Diluted solution containing casirivimab and imdevimab: If immediate administration not possible, may store in a refrigerator (2–8°C) for up to 36 hours or at room temperature (up to 25°C) for up to 7 hours, including infusion time.1

Compatibility

For information on systemic interactions resulting from concomitant use, see Interactions.

Parenteral

Solution Compatibility1

Compatible

Sodium chloride 0.9%

Actions and Spectrum

  • Casirivimab (IgG1κ) and imdevimab (IgG1λ) are SARS-CoV-2-specific recombinant human monoclonal antibodies;1 produced using recombinant DNA technology in Chinese hamster ovary (CHO) cell suspension cultures.1

  • The drugs bind to non-overlapping epitopes of the spike protein receptor-binding domain (RBD) of SARS-CoV-2 and block the spike protein from attaching to the human angiotensin-converting enzyme 2 (ACE2) receptor, thereby preventing the virus from entering cells and inhibiting viral replication.1

  • In an in vitro SARS-CoV-2 virus neutralization assay in Vero E6 cells, casirivimab, imdevimab, and the combination of casirivimab and imdevimab neutralized SARS-CoV-2 (USA-WA1/2020 isolate) with estimated 50% effective concentrations (EC50s) of 0.006, 0.006, and 0.005 mcg/mL, respectively.1

  • In rhesus macaques, casirivimab and imdevimab given 1 day after infection resulted in approximately a 1- to 2-log10 reduction in genomic and sub-genomic viral RNA in nasopharyngeal and oral swabs obtained at day 4 in most animals, and reduced lung pathology relative to placebo-treated animals.1 In hamsters, casirivimab and imdevimab given 1 day after infection resulted in reduced weight loss relative to placebo-treated animals, but had no clear effects on viral load in lung tissue.1 Clinical relevance of these findings from animal models not known.1

  • There is a potential risk of treatment failure due to development of viral variants resistant to casirivimab and imdevimab.1

  • Escape variants were identified following passage in cell culture of recombinant vesicular stomatitis virus (VSV) pseudoparticles encoding SARS-CoV-2 spike protein in the presence of either casirivimab or imdevimab alone, but not following passage in the presence of the combination of casirivimab and imdevimab.1 Variants with reduced susceptibility to casirivimab included spike protein amino acid substitutions K417E, Y453F, L455F, F486V, and Q493K; variants with reduced susceptibility to imdevimab included amino acid substitutions K444Q and V445A.1 Each variant showing reduced susceptibility to one of the drugs retained susceptibility to the other drug, and all variants retained susceptibility to the combination of casirivimab and imdevimab.1

  • Interim data from a clinical trial evaluating casirivimab and imdevimab for treatment of mild to moderate COVID-19 in outpatients (NCT04425629; R10933-10987-COV-2067) indicated only one variant (G446V) occurring at an allele fraction at least 15%, which was detected in 3 of 66 patients who had nucleotide sequencing data available.1 In a VSV pseudoparticle neutralization assay, the G446V variant had reduced susceptibility (135-fold) to imdevimab compared with wild type, but retained susceptibility to casirivimab and the combination of casirivimab and imdevimab.1

  • Although clinical impact not known, casirivimab and imdevimab resistance-associated variants could have cross-resistance to other SARS-COV-2-specific monoclonal antibodies that target the RBD of the virus.1

Advice to Patients

  • The Fact Sheet for Patients, Parents, and Caregivers: Emergency Use Authorization (EUA) of Casirivimab and Imdevimab for Coronavirus Disease 2019 (COVID-19) must be provided to patients or parent/caregivers prior to administration of casirivimab and imdevimab.1 2 3

  • Inform patients or parent/caregivers that FDA authorized the emergency use of casirivimab and imdevimab, which is an investigational drug regimen that has not received FDA approval, for use in certain adults and pediatric patients with mild to moderate COVID-19 who are outpatients at high risk for progressing to severe COVID-19 and/or hospitalization.1 3

  • Inform patients or parent/caregivers that they have the option to accept or refuse casirivimab and imdevimab.1

  • Provide patients or parent/caregivers with information on available alternative treatments and the risks and benefits of those alternatives, including clinical trials.1

  • Inform patients or parent/caregivers about the significant known and potential risks and benefits of casirivimab and imdevimab, and the extent to which such risks and benefits are unknown.1

  • Advise patients treated with casirivimab and imdevimab that they should continue to self-isolate and use infection control measures (e.g., wear mask, isolate, socially distance, avoid sharing personal items, clean and disinfect “high touch” surfaces, wash hands frequently) according to CDC guidelines.1

  • Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs and herbal supplements, as well as any concomitant illnesses.3

  • Importance of women informing clinicians if they are or plan to become pregnant or plan to breast-feed.3

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Casirivimab and imdevimab are not commercially available.2 FDA issued an EUA for casirivimab and imdevimab that allows combined use of the drugs for treatment of mild to moderate coronavirus disease 2019 (COVID-19) in certain adults and pediatric patients who are outpatients at high risk for progressing to severe COVID-19 and/or hospitalization.2 Allocation of casirivimab and imdevimab for use under the EUA is being directed by the HHS Office of the Assistant Secretary for Preparedness and Response (ASPR) in collaboration with state and territorial health departments.6 The drugs will be shipped directly from an authorized US distributor (AmerisourceBergen).6 To request casirivimab and imdevimab for use under the EUA, health care providers should contact their state health departments.6 12

Casirivimab

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Parenteral

Concentrate for injection, for IV infusion only

300 mg/2.5 mL (120 mg/mL) or 1332 mg/11.1 mL (120 mg/mL)

Casirivimab

Regeneron

Imdevimab

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Parenteral

Concentrate for injection, for IV infusion only

300 mg/2.5 mL (120 mg/mL) or 1332 mg/11.1 mL (120 mg/mL)

Imdevimab

Regeneron

AHFS DI Essentials™. © Copyright 2021, Selected Revisions December 3, 2020. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.

† Use is not currently included in the labeling approved by the US Food and Drug Administration.

References

1. Regeneron. Fact sheet for health care providers: Emergency use authorization (EUA) of casirivimab and imdevimab. 2020 Nov. From FDA website. https://www.fda.gov/media/143892/download

2. US Food and Drug Administration. Letter of authorization: Emergency use authorization for use of casirivimab and imdevimab for the treatment of mild to moderate coronavirus disease 2019 (COVID-19). 2020 Nov 21. From FDA website. https://www.fda.gov/media/143891/download

3. Regeneron. Fact sheet for patients, parents, and caregivers: Emergency use authorization (EUA) of casirivimab and imdevimab for coronavirus disease 2019 (COVID-19). 2020 Nov. From FDA website. https://www.fda.gov/media/143893/download

4. Regeneron. Dear healthcare provider letter: Preventing medication errors with casirivimab and imdevimab. From Regeneron website. https://www.regeneron.com/sites/default/files/treatment-covid19-eua-preventing-medication-errors.pdf

5. US Food and Drug Administration. Frequently asked questions on the emergency use authorization of casirivimab + imdevimab. 2020 Nov 21. From FDA website. https://www.fda.gov/media/143894/download

6. US Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response (HHS/ASPR). ASPR’s portfolio of monoclonal antibody treatments for COVID-19: medical countermeasures under investigation and casirivimab and imdevimab allocation and distribution process. Accessed 2020 Nov 24. https://www.phe.gov/emergency/events/COVID19/investigation-MCM/cas_imd/Pages/default.aspx

7. Safety, Tolerability, and Efficacy of Anti-Spike (S) SARS-CoV-2 Monoclonal Antibodies for the Treatment of Ambulatory Adult Patients With COVID-19. NCT04425629. Update posted 2020 Nov 10. https://www.clinicaltrials.gov/ct2/show/study/NCT04425629

8. Safety, Tolerability, and Efficacy of Anti-Spike (S) SARS-CoV-2 Monoclonal Antibodies for Hospitalized Adult Patients With COVID-19. NCT04426695. Update posted 2020 Nov 10. https://www.clinicaltrials.gov/ct2/show/study/NCT04426695

9. US National Library of Medicine. ClinicalTrials.gov. Accessed 2020 Nov 13. https://clinicaltrials.gov

10. Regeneron. REGN-COV2 independent data monitoring committee recommends holding enrollment in hospitalized patients with high oxygen requirements and continuing enrollment in patients with low or no oxygen requirements. Press release. 2020 Oct 30. https://investor.regeneron.com/news-releases/news-release-details/regn-cov2-independent-data-monitoring-committee-recommends

11. Randomised Evaluation of COVID-19 Therapy (RECOVERY). NCT04381936. Update posted 2020 Nov 12. https://www.clinicaltrials.gov/ct2/show/study/NCT04381936

12. Regeneron. Casirivimab and imdevimab emergency use authorization EUA guidebook. 2020 Nov. From Regeneron website. https://www.regeneroneua.com/Content/pdf/treatment-covid19-eua-guide-book.pdf

13. US Department of Health and Human Services. OWS therapeutics: Monoclonal antibody and outpatient administration playbook. From HHS website. Accessed 2020 Nov 16. https://www.phe.gov/emergency/events/COVID19/investigation-MCM/Bamlanivimab/Documents/OWS_MAB_%20playbook_10Nov20-508.pdf

14. National Institutes of Health. Coronavirus disease 2019 (COVID-19) treatment guidelines. Updated 2020 Dec 2. From NIH website. Accessed 2020 Dec 2 https://www.covid19treatmentguidelines.nih.gov/

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