Besifloxacin ophthalmic suspension 0.6% in the treatment of bacterial conjunctivitis patients with Pseudomonas aeruginosa infections

BACKGROUND The purpose of this study was to determine the efficacy of besifloxacin ophthalmic suspension 0.6% when used in the treatment of bacterial conjunctivitis infections due to Pseudomonas aeruginosa. METHODS We undertook a post hoc analysis of clinical outcomes in patients with bacterial conjunctivitis due to P. aeruginosa across four prospective, multicenter, double-masked, randomized, controlled, clinical studies of besifloxacin ophthalmic suspension 0.6%. Efficacy outcomes included bacterial eradication and clinical resolution of the baseline infection at follow-up visits. Bacterial eradication was defined as the absence of ocular bacterial species present at or above threshold at baseline, while clinical resolution was defined as grade 0 ocular discharge and bulbar conjunctival injection. Safety outcomes included the incidence of adverse events, changes in visual acuity, and biomicroscopy and ophthalmoscopy findings. Patient outcomes were summarized and bacterial eradication and clinical resolution rates integrated. RESULTS Of 1317 patients with culture-confirmed bacterial conjunctivitis across four clinical studies, nine (0.7%) were infected with P. aeruginosa at baseline, and of these, five were randomized to treatment with besifloxacin ophthalmic suspension 0.6%. Bacterial eradication of the baseline infection was observed at both follow-up visits in all five patients. Clinical resolution was achieved in two of five patients by the first follow-up visit and four of five patients by the second follow-up visit. There were no adverse events reported in these patients. There were no clinically meaningful biomicroscopy findings or changes in ophthalmoscopy or visual acuity. CONCLUSION The incidence of bacterial conjunctivitis due to P. aeruginosa was low. Treatment of patients with P. aeruginosa infections with besifloxacin ophthalmic suspension 0.6% led to bacterial eradication of P. aeruginosa by the first follow-up visit and high rates of clinical resolution.