USE OF QUINOXALINES COMBINED WITH PROTEASE INHIBITOR AS DRUG FOR TREATMENT OF AIDS AND/OR HIV INFECTIOUS DISEASE

PROBLEM TO BE SOLVED: To obtain a medicine effective for treating AIDS and/or HIV infection composed of a protease inhibitor and a specific quinoxaline (a tautomer). SOLUTION: This medicine contains (A) a protease inhibitor and (B) a quinoxaline of formula I or formula II [(n)=0-4; R is a halogen, trifluoromethyl, etc.; R and R are each H, OH, a 1-6C alkoxy, etc.; R and R are each H, a (substituted) 1-8C alkyl, etc.] and/or a tautomer of formula II. Further, as a preferable combination of the component A and the component B, the combination of (S)-N-[(α-S)-α-[(1R)-2- [(3S,4aS,8aS)-3-(t-butylcarbamoyl)octahydro-2(1H)- isoquinolinyl-1-hydroxyethyl]phenylethyl-2-quinaldamide}succinimide of formula III and S-4-isopropoxycarbonyl-6-methoxy-3-(methylthiomethyl)-3,4- dihydroquinoxazoline-2(1H)-thione of formula IV is cited.