Acquired immune deficiency syndrome (AIDS) is a difficult disease to treat because of the complex pathogenesis of the disease. Biological response modifiers (BRM), specifically immunomodulators, have been the subject of considerable research and effort as an approach for enhancing current antiviral therapies.

Prophylactic treatment, using the BRM imexon (4-imino-1,3-diazobicyclo-(3.1.0)-hexan-2-one), has been shown in a very limited study to be effective in reducing Friends virus complex (FV)-induced splenomegaly in mice. In this report, we have used a murine model recently described for evaluating BRMs for the treatment of retroviral infection. A mouse strain, (B10.A X A/WySn)F1, was used that is capable of eliciting a specific retroviral immune response analogous to that seen in AIDS, that is, viral-specific antibodies are produced soon after viral challenge despite the occurrence of immunosuppression. The production and persistence of the antibodies are correlated with a reduction of the infected cells and viremia. Regardless of the virus-specific immune response, the disease is fatal.