Properties and Mechanism of Human Immunoglobulin (pH4) for Intravenous Injection
Introduction
Human immunoglobulins (HIs) are concentrated antibody preparations that are purified from pooled human plasma donated by healthy donors. These immunoglobulins play an important role in modulating and enhancing the immune system. One such preparation is Human Immunoglobulin (pH4) for Intravenous Injection.
Composition and Source
Human Immunoglobulin (pH4) for Intravenous Injection is a sterile, nonpyrogenic preparation of concentrates of purified human serum immunoglobulin G (IgG). It is isolated from pooled adult donor plasma using a process that results in a product that has been treated to remove and/or inactivate potential viral and/or other pathogens. The product contains predominantly IgG, with IgA levels less than 35 mg/dL and IgM levels less than 50 mg/dL. IgG subclasses are also present in the product. The protein content is determined by weighing amino acids after hydrolysis.
Mechanism of Action
HIs act through several mechanisms to help support antibody-mediated immunity. IgG antibodies present in the HI product can help neutralize bacterial toxins and viruses by binding to them. This prevents the pathogens from attaching to and entering host cells. IgG molecules can also opsonize (coat) antigenic substances present in the circulation, which promotes their interaction with phagocytes and subsequent destruction.
In addition, HIs can modulate immune response by providing functional IgG antibodies that interact with effector cells through their Fc receptors. For example, monocytes, natural killer cells, and macrophages use Fc receptors to identify and clear antibody-coated pathogens and immune complexes. By supplying functional antibodies, HIs may help restore the immune system’s ability to clear pathogens.
Indications
The primary indication for Human Immunoglobulin (pH4) for Intravenous Injection is replacement therapy in patients with certain immunodeficiencies, including:
– Primary humoral immunodeficiency (PI) – Patients with recurrent bacterial infections and impaired antibody production. Deficiency involves one or more components of the immune system such as IgG subclasses, IgA, or IgM.
– Chronic lymphocytic leukemia (CLL) – Suppression of immunoglobulin levels seen with this form of leukemia puts patients at risk of infection.
– Multiple myeloma (MM) – Characterized by overproduction of abnormal proteins which can damage antibody-producing cells.
– HIV infection – Exposure to and replication of HIV can damage B lymphocytes over time, reducing antibody levels.
Other potential off-label uses of IVIG include Kawasaki disease, immune thrombocytopenia purpura (ITP), Guillain-Barré syndrome (GBS), and transplant rejection prevention in bone marrow transplantation.
Administration and Dosing
Human Immunoglobulin (pH4) for Intravenous Injection is administered intravenously (IV). It must be administered slowly, starting at 1-2 mg/kg/min and increasing gradually if well tolerated, to reduce the risk of adverse reactions. Infusions are typically given every 3-4 weeks depending on the indication. A few guidelines on dosing include:
– Primary humoral immunodeficiency: 300-600 mg/kg every 3-4 weeks to achieve a trough level of at least 5 g/L.
– Kawasaki disease: 2 g/kg administered as a single dose over 10-12 hours along with aspirin.
– ITP or GBS: 0.4 g/kg/day for 5 days or 400 mg/kg/day for 2-5 days, respectively.
The dose may need adjusting based on the clinical response, tolerance, and maintenance of adequate antibody levels in the patient’s blood.
Precautions and Warnings
IVIG therapy requires screening of patients for adverse reactions risk factors. Those with renal impairment, cardiac conditions, or prior thrombosis may be at higher risk. Vital signs, including temperature, should be monitored during and after infusion. Some potential side effects include headache, fever, chills, nausea, and changes in blood pressure or pulse.
Severe reactions like renal impairment, aseptic meningitis, thromboembolism, and hemolysis have also been reported, especially at higher doses or rapid infusion rates. A trial dose may be recommended initially in higher risk patients. Precautions must also be taken to minimize the potential for transmitting infectious agents.
Conclusion
Human Immunoglobulin (pH4) for Intravenous Injection is a concentrated IgG preparation purified from pooled donor plasma that provides a replacement therapy option for certain immunodeficiency states and inflammatory conditions. Through its antibody-mediated functions and immunomodulatory properties, it helps restore humoral immunity and support the patient’s ability to fight infection. Careful administration and monitoring are required due to potential risks from IVIG therapy.
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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile
