Linezolid: A new antibiotic

The U.S. Food and Drug Administration recently approved linezolid for the t reatment of patients with methicillin-resistant staphylococcal and vancomyc in-resistant enterococcal infections. This oxazolidinone antibacterial agen t represents the first approved antibiotic of a new structural class in 35 years. Linezolid is a synthetic compound that acts by inhibiting the initia tion complex formation in bacterial protein synthesis, a mechanism of actio n distinct from other commercially available antibiotics. Thus, cross-resis tance between linezolid and other current antimicrobial agents has not been demonstrated to date. Linezolid has a wide spectrum of in vitro activity a gainst Gram-positive organisms, including methicillin-resistant staphylococ ci, penicillin-resistant pneumococci and vancomycin-resistant enterococci. Some anaerobes, such as Clostridium spp., Peptostreptococcus spp. and Prevo tella spp. are also susceptible to linezolid. In addition, linezolid has ex hibited good efficacy in experimental animal models of acute otitis media, endocarditis and meningitis due to many common aerobic Gram-positive bacter ia. In clinical trials involving hospitalized patients with skin/soft tissu e infections, community-acquired pneumonia and serious Gram-positive bacter ial infections, linezolid appeared to be an effective treatment option, com parable in efficacy to vancomycin. (C) 2000 Prous Science. All rights reser ved.