title: Potential contribution of mild pepsin treatment at pH4 to the viral safety of human immunoglobulin products.
abstract: Different manufacturers use several different processes for the production of intravenous immunoglobulin. Several manufacturers include a production step where the immunoglobulin is treated with low levels of pepsin at pH 4. A series of experiments were undertaken to assess whether or not pH 4/pepsin treatment could inactivate a range of test viruses. Acid-labile viruses such as vaccinia, herpes simplex, mumps and Semliki Forest virus were found to be susceptible to pH 4/pepsin treatment whereas poliovirus type 2, an acid-stable virus, was completely resistant to this treatment. In immunoglobulin preparations, viral contaminants are likely to be present as antibody/virus complexes and such complexing was found to help protect the test viruses from inactivation by pH 4/pepsin treatment. Despite this protection, at least 99% of the test inoculum of two susceptible viruses (vaccinia and herpes simplex) was found to be inactivated after treatment and the subsequent dissociation of virus/antibody complexes. It is concluded that pH 4/pepsin treatment may contribute to the safety of intravenous IgG by inactivating potential viral contaminants.
mesh_terms: D000914:Antibodies, Viral / Q000276:immunology; D004340:Drug Contamination / Q000517:prevention & control*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007074:Immunoglobulin G / Q000276:immunology; D007136:Immunoglobulins / Q000276:immunology / Q000592:standards*; D010434:Pepsin A / Q000494:pharmacology*; D014780:Viruses / Q000187:drug effects* / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007136:Immunoglobulins; D010434:Pepsin A