Researchers at the University of Southern California have developed the first protease inhibitor that requires only once-a-day dosing. All six currently available protease inhibitors are dosed either twice or three times daily. Unveiled at the 8th Annual Conference on Retroviruses and Opportunistic Infections, the experimental drug, called BMS-232632, has proved in initial tests to be safe, well tolerated, and effective in preventing HIV replication. Data from 480 Phase I and Phase II test subjects showed comparable effectiveness of BMS-232632 to nelfinavir (Viracept), even at doses five to 10 times lower than nelfinavir. The experimental medication has shown no signs of increasing cholesterol and triglycerides levels, which are a common side effect of existing protease inhibitors. Reported side effects were significantly lower than with other protease inhibitors, particularly in regard to drug-related diarrhea. Investigators will soon begin Phase III testing of the medication in cooperation with pharmaceutical company Bristol-Myers Squibb.