Dosing and uses of Anthrasil (anthrax immune globulin)
Adult dosage forms and strengths
intravenous solution
- 40-70mg/vial; variable fill volume per vial of total protein concentrate
Anthrax Exposure
Indicated for treatment of inhalational anthrax in combination with appropriate antibacterial drugs
≥17 years: 420 units (7 vials) IV; initiate IV infusion at 0.5 mL/min for 30 min; if tolerated, may increase infusion rate by 0.5 mL/min q30min; not to exceed 2 mL/min
Select initial dose based on clinical severity; severe cases may warrant use of 14 vials (840 units) in adults
Dosage considerations
Effectiveness is based solely on efficacy studies conducted in animal models of inhalational anthrax
Does not cross the blood-brain barrier and does not prevent or treat meningitis
Does not have direct antibacterial activity
Adult dosage of 420 units (7 vials) contains up to 0.368 g protein per kg body weight
Adult dosage of 840 units (14 vials) contains up to 0.736 g protein per kg body weight
Pediatric dosage forms and strengths
intravenous solution
- 40-70mg/vial; variable fill volume per vial of total protein concentrate
Anthrax Exposure
Indicated for treatment of inhalational anthrax in combination with appropriate antibacterial drugs
≤16 years: 60-420 units (1-7 vials) IV; initiate IV infusion at 0.01 mL/kg/min for 30 min; if tolerated, may increase infusion rate by 0.02 mL/kg/min q30min; not to exceed 0.04 mL/kg/min
Do not exceed adult infusion rate when initiating (ie, 0.5 mL/min) or for maximum infusion rate (ie, 2 mL/min)
Select initial dose based on clinical severity; severe cases may warrant use of 2-14 vials (based on weight) in pediatric patients weighing >5 kg
Vials needed by weight
- <10 kg: 1 vial
- 10 to <18 kg: 2 vials
- 18 to <25 kg: 3 vials
- 25 to <35 kg: 4 vials
- 35 to <50 kg: 5 vials
- 50 to <60 kg: 6 vials
- ≥60 kg: 7 vials
Dosing Considerations
Effectiveness is based solely on efficacy studies conducted in animal models of inhalational anthrax
Does not cross the blood-brain barrier and does not prevent or treat meningitis
Does not have direct antibacterial activity
Protein load exposure to pediatric patients may range from 0.32 to 1.26 g per kg of body weight, depending on the weight-based pediatric dose
Anthrasil (anthrax immune globulin) adverse (side) effects
>10%
Headache (20.4%)
1-10%
Nausea (9.3%)
Infusion site pain (9.3%)
Infusion site swelling (7.4%)
Back pain (3.7%)
Warnings
Black box warnings
Falsely high blood glucose levels
- Maltose in immune globulin products, including anthrax immune globulin, may give falsely high blood glucose levels with some blood point-of-care glucose testing systems (eg, those based on the GDH-PQQ or glucose-dye-oxidoreductase methods), possibly resulting in inappropriate administration of insulin and life-threatening hypoglycemia
- To avoid interference by maltose, perform blood glucose measurements with a glucose-specific method (monitor and test strips)
Thrombosis
- May occur with immune globulin products
- Risk factors include advanced age, prolonged immobilization, hypercoagulable conditions, history of venous or arterial thrombosis, use of estrogens, indwelling vascular catheters, hyperviscosity, and cardiovascular risk factors
- Thrombosis may also occur in the absence of known risk factors
- For patients at risk of thrombosis, administer at the minimum infusion rate practicable
- Ensure adequate hydration in patients before administration
- Monitor for signs and symptoms of thrombosis and assess blood viscosity in patients at risk of hyperviscosity
Contraindications
History of anaphylaxis or prior severe systemic reaction associated with the parenteral administration of this or other human immune globulin preparations
IgA deficiency with antibodies against IgA and a history of IgA hypersensitivity, as it contains trace amounts of IgA (≤40 mcg/mL)
Cautions
Hypersensitivity reactions may occur
Contains maltose; may interfere with certain types of blood glucose monitoring systems (see Black box warnings)
Thrombosis may occur following treatment with immune globulin products (see Black box warnings)
Adverse reactions (eg, chills, fever, headache, nausea, vomiting) may be related to the rate of infusion; follow closely the recommended infusion rate
Hemolytic anemia and hemolysis may develop; anthrax immune globulin may contain blood group antibodies that may act as hemolysins and induce in vivo coating of red blood cells with immune globulin, causing a positive direct antiglobulin reaction and hemolysis
Aseptic meningitis syndrome, noncardiogenic pulmonary edema, and blood-borne infections may occur in association with administration of immune globulin products
Renal impairment
- Acute renal dysfunction, acute renal failure, osmotic nephropathy, acute tubular necrosis, proximal tubular nephropathy, and death may occur upon use of immune globulin intravenous products
- Caution with any degree of preexisting renal insufficiency and in patients at risk of developing renal insufficiency (including, but not limited to, those with diabetes mellitus, aged >65 yr, volume depletion, paraproteinemia, sepsis, and concurrent nephrotoxic drugs)
- Administer at the minimum rate of infusion if practicable and ensure that patients are not volume depleted before infusion; do not exceed the recommended infusion rate
- Assess renal function, including BUN and serum creatinine, before initiating and at appropriate intervals thereafter If renal function deteriorates, consider discontinuing
- Most cases of renal insufficiency following administration of immune globulin products have occurred in patients receiving total doses containing ≥400 mg/kg of sucrose; anthrax immune globulin does not contain sucrose
Pregnancy and lactation
There are no human data to establish the presence or absence of associated risk during pregnancy or while breastfeeding
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Anthrasil (anthrax immune globulin)
Mechanism of action
Purified human intravenous immune globulin G (IgG) containing polyclonal antibodies that provides passive immunization that neutralizes anthrax toxin
Binds to protective antigen (PA) to prevent PA-mediated cellular entry of anthrax edema factor and lethal factor
Administered in combination with appropriate antibiotic therapy as the immune globulin by itself is not known to have direct antibacterial activity against anthrax bacteria, which otherwise may continue to grow and produce anthrax toxins
It is prepared using plasma collected from healthy, screened donors who have been immunized with anthrax vaccine adsorbed (BioThrax)
Pharmacokinetics
The following parameters were measured at 3 different dosage levels (ie, 210 units, 420 units, and 840 units), respectively
AUC 0-4: 1031.8, 2176.7, and 4271 mU•d/mL
AUC 0-∞: 1277.5, 2536.7, 4788.8 mU•d/mL
Peak plasma concentration: 83, 156.4, and 316.7 mU/mL
Peak plasma time: 0.116, 0.12, and 0.169 days
Half-life: 24.3, 28.3, and 28 days
Vd: 5714.8, 6837.2, and 7238.2 mL
Clearance: 174.2, 169.7, and 188.6 mL/day
Administration
IV Preparation
Each vial has a minimum potency of ≥60 units/viaL
Bring vials to room temperature
- Thaw frozen vials rapidly for immediate use by placing at room temperature for 1 hr followed by a water bath at 37°C (98.6°F) until thawed
- Alternatively, thaw vials by placing the required number of vials in a refrigerator at 2-8°C (36-46°F) until the vials are thawed (approximately 14 hr)
- Do not thaw in a microwave oven
- Do not refreeze vials
- Bring thawed vials to room temperature by letting sit on a bench for a few minutes prior to infusion
Inspect vials
- Inspect vials to ensure the product is fully thawed and free from discoloration and particulate matter
- Solution should be clear or slightly opalescent
- Do not use solutions that are cloudy, turbid, or have particulates
- Inspect vials to ensure there is no damage to the seal or vial
- If damaged, do not use and contact the manufacturer
- Gently swirl upright vials by hand to ensure uniformity
- Do not shake the vial during preparation to avoid foaming
IV infusion bag preparation
- Remove the protective caps from the product vials
- Wipe the exposed central portion of the rubber stopper with an isopropyl alcohol swab
- Withdraw the vial contents into a syringe, aseptically transfer into an appropriately sized IV bag, and label with the volume to be infused
- No further dilution is required
- Once punctured, use the vial contents to prepare the infusion bag and administer as soon as possible
- Contains no preservative
IV Administration
Administer in an IV line with constant infusion pump
Use of an in-line filter is optionaL
If adverse reactions occur (eg, flushing, headache, nausea, changes in pulse rate, or blood pressure), slow the rate of infusion or temporarily stop the infusion
Vials are for single use only
Discard any unused portion
Adult infusion rate
- Initial: 0.5 mL/min for 30 min
- If tolerated, may increase infusion rate by 0.5 mL/min q30min; not to exceed 2 mL/min
Pediatric infusion rate
- Initial: 0.01 mL/kg/min for 30 min
- If tolerated, may increase infusion rate by 0.02 mL/kg/min q30min; not to exceed 0.04 mL/kg/min
- Do not exceed adult infusion rate when initiating (ie, 0.5 mL/min) or for maximum infusion rate (ie, 2 mL/min)
Storage
Store frozen at or below -15°C (≤5°F) until required for use
Do not use after expiration date
Once punctured, use the vial contents to prepare the infusion bag and infuse as soon as possible
Contains no preservative
Do not refreeze, reuse, or save for future use
Discard any partially used vials