Efficacy of ofloxacin otic solution once daily for 7 days in the treatment of otitis externa: a multicenter, open-label, phase III trial.

BACKGROUND

Otitis externa (OE) is an infection of the external auditory canal that is typically treated with topically applied broad-spectrum antibiotics. Twice-daily topical treatment with ofloxacin otic 0.3% solution for 10 days has been reported to be as effective and well tolerated as the standard of care, neomycin sulfate/polymyxin B sulfate/hydrocortisone solution administered 4 times daily for 10 days.

OBJECTIVE

This study evaluated the efficacy and safety profile of 7 days of a once-daily regimen of ofloxacin otic 0.3% solution in the treatment of OE.

METHODS

This multicenter, open-label, Phase III study was conducted from June 12, 2002, to October 14, 2002. Eligible patients were aged > or = 6 months and had OE of <2 weeks' duration with moderate to severe edema and tenderness involving 1 or both ears and sufficient exudate for microbiologic culture. Ofloxacin otic solution was instilled once daily for 7 days (5 drops for children aged 6 months to <13 years, 10 drops for adolescents/adults aged > or = 13 years). Assessments were conducted at the end-of-treatment visit and 7 to 10 days later (the test-of-cure visit). Medication was supplied free of charge to study participants who incurred no costs for physician visits.

RESULTS

Of 489 patients enrolled at 58 sites in 3 countries, 439 were clinically evaluable (173 children, 266 adolescents/adults; 52 % males, 48% females; 47% Hispanic, 45% white; 5% black, and 3% other). The cure rate among clinically evaluable patients was 91% (95% of children, 88% of adolescents/adults); 68% of patients were cured within 7 days. Forty-three potentially pathogenic strains were isolated from 253 microbiologically evaluable patients. Pseudomonas aeruginosa was isolated from 158 (62%) microbiologically evaluable patients and Staphylococcus aureus from 32 (13%). Eradication rates were 96% overall. No serious adverse events were observed. Minor adverse events were experienced by 15 (3%) of 489 patients included in the safety population. The most common adverse events were pruritus (5 patients), increased earache (4 patients), and application-site reactions (3 patients). Overall mean (SD) adherence to therapy was 98% (11.9).

CONCLUSIONS

Ofloxacin otic 0.3% solution administered once daily for 7 days was well tolerated and effective in achieving clinical and microbiologic cure of OE. The compliance rates in this study suggests that this regimen may be better accepted by patients than longer, more repetitive regimens.