Besifloxacin: a novel anti-infective for the treatment of bacterial conjunctivitis

Abstract

Bacterial conjunctivitis, commonly known as pink eye, is demographically unbiased in its prevalence and can be caused by a variety of aerobic and anaerobic bacteria. Timely empiric treatment with a broad-spectrum anti-infective, such as a topical fluoroquinolone, is critical in preventing potentially irreversible ocular damage. However, the rise in ocular methicillin- resistant Staphylococcus aureus isolates and the patterns of fluoroquinolone resistance for patients with other ocular bacterial infections mandate the need for new agents targeted for ocular use. Besifloxacin, a novel broad-spectrum fluoroquinolone, is approved for the treatment of bacterial conjunctivitis. It has a uniquely balanced dual-targeting activity that inhibits both DNA gyrase and topoisomerase IV and is associated with a lower incidence of resistance development. Besifloxacin is not marketed in other formulations, ensuring that its exposure is limited to bacterial populations in and around the eye. This specifically precludes any bacterial exposure to besifloxacin resulting from systemic use, which further reduces the likelihood of emergence of bacterial resistance. In vitro, besifloxacin has demonstrated equivalent or superior activity compared with other commonly used topical antibiotics. In clinical trials, besifloxacin has consistently demonstrated efficacy and safety in the treatment of patients with bacterial conjunctivitis. Besifloxacin is considered safe and is well tolerated with no observed contraindications.

Keywords: bacterial conjunctivitis; besifloxacin; besivance; conjunctivitis; fluoroquinolones.

Figure 1

Structure of besifloxacin hydrochloride.

Figure 2

Dual-targeted mechanism of action for besifloxacin. Besifloxacin binds to and inhibits 2 enzymes that are essential for maintaining bacterial DNA in the proper conformation required for DNA transcription into RNA, DNA replication, and bacterial cell division.