Prophylaxis of CMV infection in bone marrow transplant recipients by hyperimmune CMV gamma-globulin.

Prophylactic administration of an intravenous hyperimmune CMV IgG in bone marrow transplant recipients resulted in the complete protection against development of CMV infections and interstitial pneumonia. Incidence of severe graft versus host disease was markedly reduced and there was no mortality in the CMV IgG group. Mortality in those receiving standard supportive therapy was 27%. The source of hyperimmune plasma, method of fractionation and properties of the IgG are described. The effectiveness of this hyperimmune CMV IgG is related to the high content of antiviral antibodies, the dosage, the fact that it is intact, 99% monomeric, and essentially devoid of the IgG3 subclass. The timing of administration together with its effectiveness suggests this preparation might be effective in the treatment of established disseminated CMV infections.