Gemifloxacin is a novel antibiotic and the first fluoroquinolone with a pyrrolidine derivative at the C-7 position. Because of the added pyrrolidine substitute, gemifloxacin has an enhanced spectrum of activity against Gram-positive bacteria such as Streptococcus pneumoniae and Staphylococcus aureus, in addition to its activity against Gram-negative bacteria. Like other fluoroquinolones, gemifloxacin's mechanism of action focuses on inhibiting DNA gyrase and topoisomerase, thus preventing cellular replication. In addition, in vitro and in vivo data have shown that the compound exhibits excellent activity against Enterobacteriaceae and other respiratory pathogens. Furthermore, it has been demonstrated that gemifloxacin has potential activity in vitro against anaerobic bacteria. With a broad spectrum of activity, convenient once-daily administration, good bio-availability and tolerability, gemifloxacin will be an important addition to our armamentarium against a wide range of infections, from urinary tract infections to community-acquired pneumonia. (c) 2001 Prous Science. All rights reserved.