Abstract
Purpose: :
Emerging bacterial resistance is an important consideration in the treatment of bacterial infections of the eye. The purpose of this study was to assess the clinical efficacy of besifloxacin ophthalmic suspension, 0.6% against ocular infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) across four clinical studies of besifloxacin in the treatment of bacterial conjunctivitis.
Methods: :
Cases of bacterial conjunctivitis caused by MRSA and MRSE were pooled from three bacterial conjunctivitis clinical trials evaluating besifloxacin ophthalmic suspension 0.6% administered TID for 5 days (two vehicle-controlled and one active-controlled) and one bacterial conjunctivitis trial evaluating besifloxacin administered BID for 3 days. Rates for bacterial eradication in the pooled sample were summarized for each follow-up visit with the first follow-up visit occurring at or near the end of treatment and the second follow-up visit occurring on Day 7 through 9.
Results: :
There were a total of 12 patients with MRSA and 37 patients with MRSE cultures at baseline that were randomized to treatment with besifloxacin ophthalmic suspension across the 4 studies. Concurrent ciprofloxacin resistance was observed in 83% (10/12) of MRSA infections and 43% (16/37) of the MRSE infections. The rate of bacterial eradication at the first and second follow-up visit was 75% (9/12) and 83% (10/12) in patients with MRSA infections at baseline and 70% (7/10) and 80% (8/10) in the subset of patients with MRSA infections at baseline that were also ciprofloxacin resistant. The rate of bacterial eradication in patients with MRSE infections at baseline was 84% (31/37) and 89% (33/37) by the first and second follow-up visit, respectively; while it was 100% (16/16) by first follow-up visit in the subset of patients with MRSE infections that were also ciprofloxacin resistant.
Conclusions: :
Treatment of patients with MRSA and MRSE infections with besifloxacin ophthalmic suspension, 0.6% led to high rates of bacterial eradication by first follow up visit (end of 3 to 5 days of treatment).
Keywords: antibiotics/antifungals/antiparasitics • bacterial disease • conjunctivitis