Grepafloxacin is a monofluorinated quinolone with a cyclopropyl group at position 1, a 3-methyl-1piperazinyl group at position 7 and a methyl substitution at the 5 position, that was synthesized by Otsuka in Japan. It exhibited in vitro activity against a wide variety of both Gram-positive and Gram-negative bacteria including anaerobic species. The compound was reported to have a broad spectrum of activity, particularly against pathogens responsible for community-acquired respiratory infections including those caused by beta-lactam and macrolide-resistant strains of Streptococcus pneumoniae and Haemophilus influenzae. Japanese researchers also reported that unlike other quinolones, grepafloxacin reached high levels in the bile and might also be useful in the treatment of biliary tract infection. Grepafloxacin was administered once daily and did not require dosage adjustment for renal insufficiency, but grepafloxacin tablets were contraindicated in patients with hepatic failure. Otsuka Pharmaceutical signed a licensing agreement for grepafloxacin with GlaxoSmithKline. According to this agreement, GlaxoSmithKline had marketing rights to grepafloxacin in Europe, USA, and certain other markets. Otsuka retained rights for Japan and some Asian countries