Grepafloxacin is a once-daily fluoroquinolone[2]. Grepafloxacin exhibits potent in vitro antibacterial activity against Gram-positive bacteria such as Streptococcus pneumoniae and high in vivo efficacy on the experimental systemic infections caused by the Gram-positive and -negative bacteria tested[4].

Grepafloxacin (OPC-17116) (200 mg/kg; p.o.; Balb/c mice) displays good safety profile in terms of phototoxicity[2]. Grepafloxacin (p.o.; 25, 50, 100, and 200 mg/kg; 5 days/week for 4 weeks; Female C57BL6/J-Lyst bg-J/ mice/beige mice) has modest activities in both intranasal (IN) infection and intravenous (IV) Mycobacterium avium infection models[3].