Acute otitis externa: efficacy and tolerability of N-chlorotaurine, a novel endogenous antiseptic agent.
OBJECTIVE
The study's objective was to test the tolerability and efficacy of the endogenous antiseptic N-chlorotaurine (NCT) in comparison with a standard clinical treatment according to a phase IIb clinical trial protocol.


METHODS
The antimicrobial agent NCT was compared with the antibiotic component drops Otosporin (containing neomycin, polymyxin B, and hydrocortisone) for topical treatment of acute otitis externa in a randomized and rater-blinded clinical study.


METHODS
Fifty patients suffering from acute otitis externa were divided into two groups according to a randomized list. The test group was treated with 1 mL of 1% aqueous NCT solution, the reference group with 1 mL of Otosporin. The substances were applied to the external ear canal at one daily session until the signs of infection disappeared. Efficacy and tolerability were evaluated daily by visual analogue scale and a six-step infection score. In addition, smears were analyzed to identify the causative pathogens.


RESULTS
Both medications were equally well tolerated by the patients. The treatment was successful for all patients of the NCT group, whereas in one patient from the reference group, the infection did not disappear. The inflammation score improved more rapidly in the NCT group, which resulted in an earlier termination of the therapy. This difference became highly significant on days 4 to 7 (P <.01 each). Time needed for disappearance of inflammation (score 0) was 5.6 +/- 1.6 (mean +/- SD, range 3-9) days in the NCT group and 7.4 +/- 1.6 (range 4-10) days in the Otosporin group (P <.001). As expected, microbiologic cultures from ear swabs revealed Pseudomonas aeruginosa (58%) followed by Staphylococcus aureus (18%) as the main causative pathogens.


CONCLUSIONS
NCT appears to be well tolerated and more effective than the therapy using antibiotic component drops. Because of its endogenous nature and its higher efficacy, NCT appears to be a good choice for topical treatment of acute otitis externa.
Neher
Andreas
A
Department of Otorhinolaryngology, University Hospital of Innsbruck, Innsbruck, Austria. Andreas.Neher@uibk.ac.at
Nagl
Markus
M
Appenroth
Elisabeth
E
Gstöttner
Michaela
M
Wischatta
Martin
M
Reisigl
Franz
F
Schindler
Martin
M
Ulmer
Hanno
H
Stephan
Kurt
K
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002648:Child; D004311:Double-Blind Method; D004338:Drug Combinations; D004359:Drug Therapy, Combination / Q000627:therapeutic use; D004361:Drug Tolerance; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009355:Neomycin / Q000627:therapeutic use; D010033:Otitis Media / Q000188:drug therapy*; D011112:Polymyxin B / Q000627:therapeutic use; D013654:Taurine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use*
D000890:Anti-Infective Agents; D004338:Drug Combinations; C033225:hydrocortisone, neomycin, polymyxin B drug combination; D013654:Taurine; C043410:N-chlorotaurine; D009355:Neomycin; D011112:Polymyxin B; D006854:Hydrocortisone