In vitro and in vivo effects of quinupristin-dalfopristin against Pneumocystis carinii.
Quinupristin-dalfopristin (Q-D), which is active against bacteria and Toxoplasma gondii, was examined for its activity against Pneumocystis carinii. After 72 h of incubation with rat P. carinii in an ATP cytotoxicity assay, the 50% inhibitory concentration of Q-D was 10.6 microg/ml, a level that can be achieved in serum with high-dose administration. Q-D administered intraperitoneally at doses of 50 to 200 mg per kg of body weight per day in the treatment and 100 mg/kg/day three times per week in the prophylaxis of pneumocystosis in immunosuppressed mice reduced the organism burden up to 15- and 302-fold, respectively. We conclude that Q-D has activity against P. carinii in vitro and in vivo.
Walzer
P D
PD
Research Service, Veterans Affairs Medical Center, Cincinnati, Ohio 45220, USA. peter.walzer@med.va.gov
Ashbaugh
A
A
Collins
M
M
Cushion
M T
MT
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D007274:Injections, Intraperitoneal; D051379:Mice; D008809:Mice, Inbred C3H; D008826:Microbial Sensitivity Tests; D011010:Pneumocystis / Q000187:drug effects*; D016720:Pneumocystis Infections / Q000188:drug therapy* / Q000382:microbiology; D014769:Virginiamycin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use*
D000900:Anti-Bacterial Agents; D014769:Virginiamycin; C113825:quinupristin; D000255:Adenosine Triphosphate