3-Quinolinecarboxylic acid, 8-cyano-1-cyclopropyl-6-fluoro-7-[(4aS,7aS)-hexahydropyrrolo[3,4-b]-1,4-oxazin-6(2H)-yl]-1,4-dihydro-4-oxo-

Finafloxacin, an antimicrobial agent of the 8-cyano subclass of fluoroquinolones, was approved by the US FDA in December 2014 for treatment of acute otitis externa, commonly known as swimmer’s ear, caused by susceptible strains of Pseudomonas aeruginosa and Staphylococcus aureus. Finafloxacin was developed by MerLion Pharmaceuticals in partnership with Bayer Health Care Pharmaceuticals, and the drug was licensed by Mer- Lion to Alcon (a division of Novartis) for development and commercialization for ear infections in North America. In contrast to other marketed fluoroquinolones, which display reduced activity in slightly acidic environments, finafloxacin exhibits increased antibacterial activity at pH 5–6, with minimum inhibitory concentration values that are 4- to 8-fold lower than at neutral pH. It is highly selective for bacterial type II topoisomerases, which are involved in bacterial DNA replication, transcription, repair, and recombination, and has broad spectrum antibacterial activity against Gram-positive and Gram-negative strains, including ciprofloxacin-resistant strains.