[Recent trend for the development of new antibacterial agents].

Multidrug resistant organisms such as MRSA, PRSP, BLNAR, ESBL-producing K. pneumoniae and VRE have in recent years emerged as significant pathogens in hospitals. In this paper, I describe the recent trend for the development of new antibacterial agents that are active against these multidrug resistant organisms. A number of new cephem and carbapenem antibiotics were identified to have attractive potency against MRSA, PRSP and P. aeruginosa. These beta-lactam antibiotics had high affinity for PBP 2a of MRSA. AM-112 is a novel beta-lactamase inhibitor that has potent activity against class A, B, C and D beta-lactamases. Telithromycin, ABT-773, CP-642959 and A-217213, ketolide antimicrobials, possess several distinguishing features that are important for these microbiological profile. New extended-spectrum fluoroquinolones(BMS-284756, DQ-113, DK-570 k) with improved activity against Gram-positive pathogens have recently licensed for treatment of RTIs. Drug efflux pumps inhibitors are now under basic research.