IN-VITRO ACTIVITY OF AN ORALLY-ADMINISTERED STREPTOGRAMIN (RPR-106,972) COMPARED TO QUINUPRISTIN DALFOPRISTIN AND ERYTHROMYCIN/

The antibacterial activities of RPR 106,972 and quinupristin/dalfopris tin (RP 59,500) were determined by the broth microdilution susceptibil ity test method. No major differences were seen among MICs for 863 iso lates representing 22 species, However, there were minor twofold diffe rences in MICs for some species. On a weight-to-weight basis, the acti vities of the oral and parenteral streptogramins were essentially the same. Because the route of administration and the pharmacokinetics dif fer, it is not necessarily appropriate to extrapolate such in vitro ob servations to predict identical clinical and bacteriological response rates for the two drugs.