Besifloxacin, a new ophthalmic fluoroquinolone for the treatment of bacterial conjunctivitis.

Besifloxacin is a new fluoroquinolone anti-infective developed for ophthalmic use. Besifloxacin ophthalmic suspension 0.6% (Besivance) was recently approved for the treatment of bacterial conjunctivitis. The objective of this article is to provide a comprehensive overview of microbiological, pharmacokinetic/pharmacodynamic and clinical studies with besifloxacin. Microbiological studies have demonstrated that besifloxacin has wide-spectrum and potent activity against common ocular pathogens, including Gram-negative and Gram-positive pathogens associated with bacterial conjunctivitis, and retained activity against fluoroquinolone-resistant staphylococci and multidrug-resistant strains. In preclinical and human studies, topically applied besifloxacin had a prolonged ocular concentration and minimal systemic exposure. In clinical studies, patients randomized to besifloxacin ophthalmic suspension 0.6% experienced significantly higher rates of clinical resolution and microbial eradication than patients randomized to vehicle. Besifloxacin ophthalmic suspension 0.6% was also found to be as effective and well tolerated as moxifloxacin ophthalmic solution 0.5%. The low minimum inhibitory concentrations and high attainment of pharmacodynamic targets with besifloxacin may contribute to a lower risk for the emergence of bacterial resistance, although further studies are needed. These data indicate that besifloxacin ophthalmic suspension 0.6% is an important new option for the treatment of bacterial conjunctivitis.