Comparative in vitro antimicrobial activities of the newly synthesized quinolone HSR-903, sitafloxacin (DU-6859a), gatifloxacin (AM-1155), and levofloxacin against Mycobacterium tuberculosis and Mycobacterium avium complex

We compared the in vitro antimycobacterial activity of a new fluoroquinolone, HSR-903, with strong activity against gram-positive cocci with those of levofloxacin (LVFX), sitafloxacin (STFX), and gatifloxacin (GFLX). The MICs of the quinolones for Mycobacterium tuberculosis and Mycobacterium avium complex were in the order STFX ≈ GFLX M. tuberculosis , as did LVFX, and exhibited bacteriostatic effects against M. tuberculosis replicating in type II alveolar cells.