ANTIVIRAL PROPERTIES OF THE HIV-1 PROTEINASE-INHIBITOR RO 31-8959

The peptide derivative Ro 31-8959 has been shown to be a potent inhibi tor of HIV proteinase With an IC50 Of 2 x 10(-9) m, against HIV-1RF in acutely infected lymphoblastoid cells. This inhibition was not overco me by increasing the infectious dose or by extending the culture time. Similar antiviral activity was also obtained against HIV-2, SIV and s everal AZT-resistant strains of HIV-1. The time of addition of the inh ibitor could be delayed for 22h without significant loss of activity, supporting its mode of action as taking place late in the replication cycle of HIV-1. Ro 31-8959 also showed activity against chronically in fected cells.