AIDS: Researchers indicate that virologic failure during protease inhibitor (PI) therapy does not equate to clinical failure, and several studies reveal hopeful data on salvage therapy. One study suggests that salvage therapy after nelfinavir failure may be feasible with ritonavir/saquinavir. Other studies are showing that limited efficacy of ritonavir/saquinavir after failure of indinavir may be associated with a delay in switching to salvage therapy. Finally, some studies have shown that 9 of 12 patients who have failed multiple therapies, but were naive to nelfinavir and nevirapine and treated with d4T, ddI, 3TC, nevirapine, nelfinavir, and saquinavir, achieved undetectable viral load at 12 weeks.