Vitreous penetration of topical moxifloxacin and gatifloxacin in humans.
OBJECTIVE
To determine the vitreous penetration of the new fourth-generation topical fluoroquinolones moxifloxacin 0.5% and gatifloxacin 0.3%.


METHODS
A prospective randomized clinical trial comprising 12 eyes of 12 patients scheduled for pars plana vitrectomy between August 2003 and September 2003 was performed in a clinical practice. The patients were randomly assigned to receive topical moxifloxacin 0.5% (n = 6) or gatifloxacin 0.3% (n = 6). One half the patients in each antibiotic group received 1 drop every 15 minutes for a total of 3 doses starting 1 hour before surgery, and the other one half self-administered the antibiotic drop 4 times daily for 3 days before surgery and at 7 am on the day of surgery. Undiluted vitreous samples were obtained and analyzed using high-performance liquid chromatography.


RESULTS
Either moxifloxacin 0.5% or gatifloxacin 0.3% was detected in the vitreous in all 12 patients in the study. There was no significant difference between the mean vitreous concentration of moxifloxacin 0.5% given over 1 hour preoperatively (0.012 +/- 0.011 microg/mL) and that given in the 3-day regimen (0.011 +/- 0.008 microg/mL) (P = 0.93). There was also no significant difference between the mean vitreous concentration of gatifloxacin 0.3% given over 1 hour preoperatively (0.001 +/- 0.0003 microg/mL) and that given over 3 days (0.008 +/- 0.006 microg/mL) (P = 0.11). Vitreous concentrations of moxifloxacin 0.5% and gatifloxacin 0.3% in each eye were all lower than the 90% minimum inhibitory concentration for the commonest bacterial isolates causing endophthalmitis. With both dosing regimens, the mean vitreous concentration of moxifloxacin 0.5% was higher than that of gatifloxacin 0.3% administered at the same regimen, but this was not statistically significant.


CONCLUSIONS
Both topical moxifloxacin 0.5% and gatifloxacin 0.3% penetrated the vitreous in the uninflamed eye, but the vitreous concentrations attained were all lower than the 90% minimum inhibitory concentration for the commonest bacterial pathogens causing acute postoperative endophthalmitis.
Lions Eye Institute, Albany Medical College, 35 Hackett Boulevard, Albany, NY 12208, USA.
Patrick
P
Costello
Sophie J
SJ
Bakri
Paul M
PM
Beer
Ravinder J
RJ
Singh
Naomi S
NS
Falk
George B
GB
Peters
J Andre
JA
Melendez
D000287:Administration, Topical; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001372:Aza Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D024841:Fluoroquinolones / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000077734:Gatifloxacin; D006801:Humans; D007908:Lens, Crystalline / Q000502:physiology; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D000077266:Moxifloxacin; D009883:Ophthalmic Solutions / Q000008:administration & dosage / Q000493:pharmacokinetics; D011446:Prospective Studies; D019591:Pseudophakia / Q000378:metabolism; D011804:Quinolines / Q000008:administration & dosage / Q000493:pharmacokinetics*; D012164:Retinal Diseases / Q000601:surgery; D014821:Vitrectomy; D014822:Vitreous Body / Q000378:metabolism*; D014823:Vitreous Hemorrhage / Q000601:surgery
D000900:Anti-Bacterial Agents; D001372:Aza Compounds; D024841:Fluoroquinolones; D009883:Ophthalmic Solutions; D011804:Quinolines; D000077734:Gatifloxacin; D000077266:Moxifloxacin