Properties

Safety Information

Description

Besifloxacin is a new fluoroquinolone antibacterial for ophthalmic use. It is indicated for the treatment of bacterial conjunctivitis, one of the most common ocular infections encountered in the primary care setting. Although the previously marketed fluoroquinolones ciprofloxacin, levofloxacin, ofloxacin, gatifloxacin, and moxifloxacin have been widely used to treat bacterial conjunctivitis, their continued utility is hampered by the emergence of resistance among key ocular isolates such as Staphylococcus aureus. Besifloxacin is the first fluoroquinolone developed exclusively for topical ophthalmic use. Unlike the previously marketed fluoroquinolones, besifloxacin has not been used systemically and is not in development as a systemic agent. Its exclusive indication as a topical agent is expected to reduce the overall environmental exposure of bacteria to besifloxacin, which may contribute to a lower risk for the emergence of bacterial resistance. Fluoroquinolones derive their antibacterial activity via inhibition of two essential bacterial enzymes, DNA gyrase and topoisomerase IV, which regulate processes of DNA replication. Besifloxacin inhibits DNA gyrase and topoisomerase IV from Streptococcus pneumoniae (IC50 = 1 and 0.4 mg/ L, respectively) and Escherichia coli (IC50 = 1 and 10 mg/L, respectively).