Clinafloxacin(PD-127391) is a fluoroquinolone antibiotic.Target: AntibacterialClinafloxacin is a broad-spectrum antibiotic of the quinolone carboxylic acid category currently in development for intravenous and oral therapy of serious infections [1]. Clinafloxacin is a novel fluoroquinolone with potent broad-spectrum in vitro activity against gram-positive, gram-negative, and anaerobic pathogens. Clinafloxacin is highly active against S. pneumoniae 7785 (MIC, 0.125 μg/mL), and neither gyrA nor parC quinolone resistance mutations alone have much effect on this activity [2]. Clinafloxacin is identified as the most active fluoroquinolone against S. pneumoniae when compared with ofloxacin, levofloxacin, sparfloxacin, grepafloxacin, and trovafloxacin and is currently being evaluated as an antipneumococcal agent [3].

References:
[1]. Humphrey, G.H., et al., Pharmacokinetics of clinafloxacin enantiomers in humans. J Clin Pharmacol, 1999. 39(11): p. 1143-50.
[2]. Pan, X.S. and L.M. Fisher, DNA gyrase and topoisomerase IV are dual targets of clinafloxacin action in Streptococcus pneumoniae. Antimicrob Agents Chemother, 1998. 42(11): p. 2810-6.
[3]. Jorgensen, J.H., et al., Activities of clinafloxacin, gatifloxacin, gemifloxacin, and trovafloxacin against recent clinical isolates of levofloxacin-resistant Streptococcus pneumoniae. Antimicrob Agents Chemother, 2000. 44(11): p. 2962-8.