Abstract

PIP: Laboratory tests by Food and Drug Administration (FDA) scientists and epidemiologic data evaluated by the Centers for Disease Control (CDC) show that therapeutic immune globulin preparations carry no discernible risk of transmitting HTLV-III infection and that their clinical use should not be changed because of concerns about the transmission of acquired immunodeficiency syndrome (AIDS). FDA scientists have conducted laboratory tests to evaluate the basic fractionation process used for production of immune globulin (IG), hepatitis B immune globulin (HBIG), and intravenous immune globulin (IVIG). FDA and CDC scientists have cultured 38 lots of HBIG, IVIG, and IG, most of which contained HTLV-III antibody. HTLV-III was not recovered from any lot tested. Epidemiologic data concur with the results of the laboratory tests. Several studies have shown that recipients of HBIG and IG, including recipients of lots known to be positive for antibody to HTLV-III, did not show either serologic evidence or signs and symptoms of AIDS or other illnesses indicative of HTLV-III infection. These studies include data on 16 subjects who received HBIG that was strongly positive for HTLV-III antibody. In this group, low levels of passively acquired HTLV-III antibody were detected shortly after injection, but reactivity did not persist. 6 months after the last HBIG injection, none of the 16 patients had antibody to HTLV-III and thus were not infected with the virus. Based on the estimated half-life of globulins in plasma, it can be calculated that passively acquired antibodies might be detected in sera of recipients for as long as 6 months after administration of immune globulins. This possibility should be recognized when attempting to determine the significance of HTLV-III antibody in a patient who has recently received immune globulins, especially HBIG.