Inhibition of the replication of native and 3'-azido-2',3'-dideoxythymidine (AZT)-resistant simian immunodeficiency virus (SIV) by 3-nitrosobenzamide.

The 3-nitrosobenzamide (NOBA) drug abolishes SIV replication sharply at 20 microM concentration when CEM x 174 cells are preincubated for 1 h with the drug prior to viral infection. Treatment of CEM x 174 cells with 20 microM NOBA resulted in the inhibition of the synthesis of the DNA sequence coding for the gag gene, as determined by the PCR technique. Cell viability was directly proportional to the antiviral action of NOBA. Replication of AZT-resistant SIV 23740 in MMU 23740 cells in vitro was suppressed by NOBA in a concentration-dependent manner without significant effects on cell viability. Reverse transcriptase activity of SIVmac239 was unaffected by NOBA up to 800 microM concentration. Preincubation of two SIV strains with NOBA completely abolished their infectivity in human PHA-PBL cells. Replication of two strains of SIV in PHA-PBL cells was also inhibited by NOBA.