RPR 109413 is a highly purified, liquid intravenous immunoglobulin (IVIG) product. Its primary difference from currently marketed IVIG products is that it includes a wet heat treatment (pasteurization) as an additional safeguard against virus particles. The study was a double-blind randomized Phase II comparison of the safty, tolerance, efficacy, and bioligical half-life of RPR 109413 and Gamimune N( (10% solutions) administered intravenously at a dose ranging from 200 mg/kg to 600 mg/kg to more than 80 patients with primary or secondary immune deficiency characterized by defective antibody synthesis. The patients were treated as outpatient.