WARNINGS AND PRECAUTIONS
- Weigh the potential risks and benefits of Gammaplex against those of alternative therapies in all patients for whom Gammaplex is being considered.
- Before prescribing Gammaplex, the physician should discuss the risks and benefits of its use with the patient.
Hypersensitivity
Severe hypersensitivity reactions may occur (see
Contraindications [4]
). In case of hypersensitivity, discontinue Gammaplex infusion immediately and institute appropriate treatment. Medications such as epinephrine should be available for immediate treatment of acute hypersensitivity reactions.
Gammaplex contains trace amounts of IgA (<10 μg/mL) (s ee Description [11]
). Patients with known antibodies to IgA may have a greater risk of developing potentially severe hypersensitivity and anaphylactic reactions. Gammaplex is contraindicated in patients with antibodies against IgA and a history of hypersensitivity reaction (see Contraindications [4]
).
Renal Dysfunction/Failure
Acute renal dysfunction/failure, osmotic nephropathy, and death1 may occur upon use of human IGIV products. Ensure that patients are not volume depleted before administering Gammaplex. In patients who are at risk of developing renal dysfunction, because of pre-existing renal insufficiency or predisposition to acute renal failure (such as diabetes mellitus, hypovolemia, overweight, use of concomitant nephrotoxic medicinal products or age of >65 years), administer Gammaplex at the minimum infusion rate practicable (see Dosage and Administration [2.3]
).
Periodic monitoring of renal function and urine output is particularly important in patients judged to be at increased risk of developing acute renal failure. Assess renal function, including measurement of blood urea nitrogen (BUN) and serum creatinine, before the initial infusion of Gammaplex and at appropriate intervals thereafter. If renal function deteriorates, consider discontinuing Gammaplex.
Hyperproteinemia, Increased Serum Viscosity, and Hyponatremia
Hyperproteinemia, increased serum viscosity, and hyponatremia may occur in patients receiving IGIV therapy. It is critical to clinically distinguish true hyponatremia from a pseudohyponatremia that is associated with or causally related to hyperproteinemia with concomitant decreased calculated serum osmolality or elevated osmolar gap, because treatment aimed at decreasing serum free water in patients with pseudohyponatremia may lead to volume depletion, a further increase in serum viscosity, and a possible predisposition to thrombotic events.2
Thrombotic Events
Thrombotic events may occur following treatment with Gammaplex and other IGIV products.2,3 Patients at risk include those with a history of atherosclerosis, multiple cardiovascular risk factors, advanced age, impaired cardiac output, coagulation disorders, prolonged periods of immobilization, and/or known/suspected hyperviscosity.
Consider baseline assessment of blood viscosity in patients at risk for hyperviscosity, including those with cryoglobulins, fasting chylomicronemia/markedly high triacylglycerols (triglycerides), or monoclonal gammopathies. For patients judged to be at risk of developing thrombotic events, administer Gammaplex at the minimum rate of infusion practicable (see Dosage and Administration [2.3]
).
Aseptic Meningitis Syndrome (AMS)
AMS may occur infrequently with IGIV treatment. AMS usually begins within several hours to 2 days following IGIV treatment. Discontinuation of IGIV treatment has resulted in remission of AMS within several days without sequelae.4
AMS is characterized by the following signs and symptoms: severe headache, nuchal rigidity, drowsiness, fever, photophobia, painful eye movements, nausea, and vomiting (see Patient Counseling Information [17]
). Cerebrospinal fluid (CSF) studies frequently reveal pleocytosis up to several thousand cells per cubic millimeter, predominantly from the granulocytic series, and elevated protein levels up to several hundred mg/dL, but negative culture results. Conduct a thorough neurological examination on patients exhibiting such signs and symptoms, including CSF studies, to rule out other causes of meningitis.
AMS may occur more frequently in association with high doses (2 g/kg) and/or rapid infusion of IGIV.
Hemolysis
IGIV products can contain blood group antibodies that may act as hemolysins and induce in vivo coating of red blood cells (RBCs) with immunoglobulin, causing a positive direct antiglobulin reaction and, rarely, hemolysis5-7. Delayed hemolytic anemia can develop subsequent to IGIV therapy due to enhanced RBC sequestration8, and acute hemolysis, consistent with intravascular hemolysis, has been reported.
Monitor patients for clinical signs and symptoms of hemolysis (see Patient Counseling Information [17]
). If these are present after Gammaplex infusion, perform appropriate confirmatory laboratory testing. If transfusion is indicated for patients who develop hemolysis with clinically compromising anemia after receiving IGIV, perform adequate cross-matching to avoid exacerbating on-going hemolysis.
Transfusion-related Acute Lung Injury (TRALI)
Noncardiogenic pulmonary edema may occur in patients following IGIV treatment9. TRALI is characterized by severe respiratory distress, pulmonary edema, hypoxemia, normal left ventricular function, and fever. Symptoms typically appear within 1 to 6 hours following treatment.
Monitor patients for pulmonary adverse reactions. If TRALI is suspected, perform appropriate tests for the presence of anti-neutrophil antibodies in both the product and the patient's serum.
TRALI may be managed using oxygen therapy with adequate ventilatory support.
Transmissible Infectious Agents
Gammaplex is made from human plasma. Based on effective donor screening and product manufacturing processes (see Description [11]
), Gammaplex carries an extremely remote risk of transmission of viral diseases. A theoretical risk for transmission of Creutzfeldt-Jakob disease (CJD) also is considered to be extremely remote. No cases of transmission of viral diseases or CJD have been associated with the use of Gammaplex. All infections suspected by a physician possibly to have been transmitted by this product should be reported by the physician or other healthcare provider to FFF on behalf of Bio Products Laboratory (800) 843-7477. Before prescribing Gammaplex, the physician should discuss the risks and benefits of its use with the patient (see Patient Counseling Information [17]
).
Monitoring: Laboratory Tests
- Periodic monitoring of renal function and urine output is particularly important in patients judged to be at increased risk of developing acute renal failure. Assess renal function, including measurement of BUN and serum creatinine, before the initial infusion of Gammaplex and at appropriate intervals thereafter.
- Because of the potentially increased risk of thrombosis, consider baseline assessment of blood viscosity in patients at risk for hyperviscosity, including those with cryoglobulins, fasting chylomicronemia/markedly high triacylglycerols (triglycerides), or monoclonal gammopathies.
- If signs and/or symptoms of hemolysis are present after an infusion of Gammaplex, perform appropriate laboratory testing for confirmation.
- If TRALI is suspected, perform appropriate tests for the presence of anti-neutrophil antibodies in both the product and patient's serum.
Interference with Laboratory Tests
- After infusion of immunoglobulin, the transitory rise of the various passively transferred antibodies in the patient's blood may yield positive serological testing results, with the potential for misleading interpretation. Passive transmission of antibodies to erythrocyte antigens (e.g., A, B, and D) may cause a positive direct or indirect antiglobulin (Coombs') test.
USE IN SPECIFIC POPULATIONS
Pregnancy
Pregnancy Category C. Animal reproduction studies have not been conducted with Gammaplex. It is also not known whether Gammaplex can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Gammaplex should be given to a pregnant woman only if clearly needed. Immunoglobulins cross the placenta from maternal circulation increasingly after 30 weeks of gestation13, 14
Nursing Mothers
Use of Gammaplex has not been evaluated in nursing mothers.
Pediatric Use
Six (6) pediatric patients with primary humoral immunodeficiency (2 between ages of 9 and 10, and 4 between ages 12 and 16) were included within the clinical evaluation of Gammaplex. This number of pediatric patients was too small for separate evaluation from the adult patients for safety or efficacy (see Clinical Studies [14]
).
Geriatric Use
Use caution when administering Gammaplex to patients age 65 and over who are judged to be at increased risk of developing renal insufficiency or thrombotic events (see Boxed Warning, Warnings and Precautions [5.2, 5.4]
). Do not exceed recommended doses, and administer Gammaplex at the minimum infusion rate practicable.
Eight (8) patients with primary humoral immunodeficiency at or over the age of 65 were included within the clinical evaluation of Gammaplex. This number of geriatric patients was too small for separate evaluation from the younger patients for safety or efficacy (see Clinical Studies [14]
).
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