A pilot study to compare tobramycin 80 mg injectable preparation with 300 mg solution for inhalation in cystic fibrosis patients.
BACKGROUND
Inhaled tobramycin has been shown to improve lung function in cystic fibrosis (CF) patients chronically infected with Pseudomonas aeruginosa. However, to date no comparative data are available for different dose regimens used in clinical practice.


OBJECTIVE
To compare the clinical efficacy of the two most commonly used treatment regimens of inhaled tobramycin in patients with CF.


METHODS
In an open crossover study of CF patients, subjects were randomly allocated to receive either 80 mg tobramycin twice-daily continuous treatment or 300 mg tobramycin twice daily in cycles of 28 days on and 28 days off treatment. After three months, patients were switched to the alternative treatment regimen.


RESULTS
A total of 32 patients with a mean (+/- SD) age of 18.5+/-8.6 years were included in the study. Compared with the treatment period using colistin, forced expiratory volume in 1 s decreased by -2.1+/-13.8% in the 80 mg tobramycin group and increased by +2.3+/-13.0% in the 300 mg group. Similar changes were observed in forced vital capacity (-2.5+/-12.9% in the 80 mg tobramycin group versus +2.5+/-9.6% in the 300 mg tobramycin group). Variability in responses was large but the differences were not statistically significant. Personal preference indicated that the majority of patients preferred the high-dose cycle compared with the lower dose continuous inhalation, but this was not linked to objective data on efficacy.


CONCLUSIONS
The present trial fails to provide convincing evidence for superiority in efficacy of either of the two treatment regimens of inhaled tobramycin in CF patients.
Nikolaizik
Wilfried H
WH
Department of Pediatrics, University Hospital Essen, Essen, Germany.
Vietzke
Delia
D
Ratjen
Felix
F
D000280:Administration, Inhalation; D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D018592:Cross-Over Studies; D003550:Cystic Fibrosis / Q000188:drug therapy* / Q000503:physiopathology; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D010865:Pilot Projects; D014031:Tobramycin / Q000008:administration & dosage*; D016896:Treatment Outcome; D014797:Vital Capacity / Q000502:physiology; D055815:Young Adult
D000900:Anti-Bacterial Agents; D014031:Tobramycin