Cefoselis sulfate is a widely used beta-lactam antibiotic. Target: Antibacterial Cefoselis sulfate, a new parenteral cephalosporin, was active against clinical isolates of both gram-positive and gram-negative aerobic bacteria. The activity of Cefoselis (sulfate) was similar to that of cefpirome and cefepime and generally superior to that of ceftazidime. Cefoselis sulfate showed potent antibacterial activity against Hemophilus influenzae and Moraxella catarrhalis. Cefoselis sulfate was highly active against MSSA and MSCNS. Cefoselis sulfate was poor in the activity against MRSA,MRCNS,PRSP and Enterococcus faecalis,and no activity for Enterococcus faecium.