Clearance of intravitreal moxifloxacin.
OBJECTIVE
To study the clearance of moxifloxacin after intravitreal injection in rabbits.


METHODS
Intravitreal injections of 200 microg/0.1 mL of moxifloxacin were administered to rabbits. Four eyes per time point after injection (1 hour and 6, 12, 24, and 36 hours) and three eyes at 48 hours, respectively, were enucleated and immediately frozen and stored at -80 degrees C. Ocular dissection and isolation of frozen vitreous was performed. Vitreous samples were acquired at the various time intervals after injection. Antibiotic assays were performed with high performance liquid chromatography.


RESULTS
The concentration of intravitreal moxifloxacin showed an exponential decay with a half-life of 1.72 hours. The mean vitreous concentration was 120.49 +/- 49.23 microg/mL 1 hour after injection, and declined to 20.23 +/- 5.85 microg/mL at 6 hours and 1.06 +/- 0.81 microg/mL at 12 hours, respectively.


CONCLUSIONS
The vitreous concentrations achieved were several orders of magnitude greater than the MIC90 of organisms commonly involved in bacterial endophthalmitis, and therapeutic levels were maintained at 12 hours in uninflamed, phakic rabbit eyes. The pharmacokinetic data suggest that intravitreal moxifloxacin may have a role in the treatment of bacterial endophthalmitis.
Iyer
Mohan N
MN
Department of Ophthalmology, Baylor College of Medicine, Houston, Texas 77030, USA.
He
Feng
F
Wensel
Theodore G
TG
Mieler
William F
WF
Benz
Matthew S
MS
Holz
Eric R
ER
D000818:Animals; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001082:Aqueous Humor / Q000378:metabolism; D001372:Aza Compounds / Q000493:pharmacokinetics*; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D024841:Fluoroquinolones; D006207:Half-Life; D007267:Injections; D008826:Microbial Sensitivity Tests; D000077266:Moxifloxacin; D011804:Quinolines / Q000493:pharmacokinetics*; D011817:Rabbits; D014822:Vitreous Body / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D001372:Aza Compounds; D024841:Fluoroquinolones; D011804:Quinolines; D000077266:Moxifloxacin