The main objective of this study was to compare in vitro activities of a novel fluoroquinolone (FQ), UB-8902, with ofloxacin (OFX), levofloxacin (LFX), and moxifloxacin (MOX) against Mycobacterium tuberculosis isolates. Eleven OFX-resistant and 11 drug-susceptible clinical isolates were studied. Individual minimum inhibitory concentrations of OFX, LFX, MOX, and UB-8902 were determined using Middlebrook 7H11 agar. The concentrations studied ranged from 0.125 to 128 μg/mL in twofold dilutions. UB-8902 was more active than LFX and similar to MOX for OFX-resistant M. tuberculosis isolates. In addition, UB-8902 and MOX showed equal activity against drug-susceptible isolates, both being more active than OFX and LFX. In conclusion, the new FQ, UB-8902, showed good activity against OFX-resistant isolates. Moreover, it showed better activity than OFX and LFX and was equivalent to MOX against FQ-susceptible clinical isolates. UB-8902 can be considered as a drug with potential antituberculous activity, similar to MOX.

中文翻译：

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新型喹诺酮UB-8902对耐氧氟沙星的结核分枝杆菌分离株的体外活性。

这项研究的主要目的是比较新型氟喹诺酮（FQ），UB-8902与氧氟沙星（OFX），左氧氟沙星（LFX）和莫西沙星（MOX）对结核分枝杆菌分离株的体外活性。研究了11株对OFX有耐药性和11株对药物敏感的临床分离株。使用Middlebrook 7H11琼脂确定OFX，LFX，MOX和UB-8902的个体最低抑菌浓度。两倍稀释的浓度范围为0.125至128μg/ mL。UB-8902比LFX更具活性，并且对耐OFX的结核分枝杆菌与MOX相似隔离株。此外，UB-8902和MOX对药物敏感的分离物具有相同的活性，两者均比OFX和LFX更具活性。总之，新的FQ UB-8902对抵抗OFX的分离株表现出良好的活性。而且，它显示出比OFX和LFX更好的活性，并且相当于对FQ敏感的临床分离株的MOX。UB-8902可以被认为是具有潜在抗结核活性的药物，类似于MOX。