Isoprinosine and Imuthiol, two potentially active compounds in patients with AIDS-related complex symptoms.

Isoprinosine and Imuthiol are immunomodulators with a unique effect on T-cells. The possibility of using them in treating patients with acquired immunodeficiency syndrome related complex (ARC) was initially examined regarding their in vitro effects on peripheral blood mononuclear cells. In six ARC patients Isoprinosine (100 micrograms/ml) and Imuthiol (10 pg/ml) induced in vitro an early chromatin activation as measured by nuclear refringency test and potentiated phytohemagglutinin (5 micrograms/ml) in the same 20-min assay in the absence of fetal calf serum. In all patients an early phytohemagglutinin induced chromatin dispersion was observed with a dose related response before interleukin 2 production can occur. Isoprinosine and Imuthiol increased significantly both the percentage and the absolute number of T4+ cells when peripheral blood mononuclear cells were incubated for 4 days in RPMI supplemented with 10% fetal calf serum. No changes in T8+ cells were noted. Three homosexual ARC patients were then treated p.o. with Imuthiol (5-10 mg/kg/week) for 4 to 6 months. Without any deleterious effect a clinical improvement (in terms of adenopathy and opportunistic infection regression) and restoration of the response to recall antigens were observed in all three patients. One patient with less than 500 T4+ lymphocytes/mm3 exhibited a complete restoration of OKT profiles. In such patients clinical and immunological effects of Isoprinosine have already been reported by others. Altogether these preliminary results indicate that more data should be obtained on the effects of these two agents in ARC patients.