[Antibiotics--TAZ/PIPC, synercid, linezolid, everninomicin]

The increasing resistance among Gram-positive cocci have been accompanied by their increasing frequency as cause of severe infection. Thus new antimicrobial agents, TAZ/PIPC, synercid and linezolid, are in various stages of development. TAZ/PIPC, a combination drug of a new beta-lactamase inhibitor tazobactam and piperacillin at ratio in 1 to 4 has a broad spectrum of antimicrobial activity. Evidence from randomized clinical trials in adults in Japan has shown that TAZ/PIPC is superior to PIPC as a drug for complicated urinary tract infection. Synercid is a streptogramin antibiotic. The spectrum of activity of synercid is similar to vancomycin. Furthermore, most of E. faecium were susceptible. The efficacy of synercid in clinical trials in patients infected with VREF was 65-70%. Linezolid is a member of the oxazolidinones. The antimicrobial spectrum of linezolid is similar to that of vancomycin. In the US, patients with significant infection caused by resistant Gram-positive organisms(mostly VREF) were treated with linezolid. The efficacy of linezolid was about 75%. The clinical trials for everninomicin had been discontinued because of insufficient clinical data supporting its efficacy and safety.