DPC-083 and DPC-961 are non-nucleoside reverse transcriptase inhibitors (NNRTIs) under development by DuPont Pharmaceuticals for the potential treatment of HIV infection [312865]. Phase I trials were completed by September 2000 [383661], and by April 2001, DPC-083 was in phase II trials as a once-daily oral dose in combination therapy, with phase III studies expected to begin in the third quarter of 2001 [392761]. NDA filing is anticipated for 2003, for which the company would expect an FDA expedited review [405548]. DPC-083 and DPC-961 possess antiviral activity against mutant variants of HIV-1, including the K103N mutant, and have the same potency as efavirenz against wild-type virus in rhesus monkeys [312865]. DuPont has also described a series of novel tricyclic quinazolinones which were found to possess noteworthy biological activity during investigation of DPC-083 and DPC-961.