Fourth-generation cephalosporins The 4th-generation cephalosporin cefepime has activity against Gram-positive cocci (similar to cefotaxime) Gram-negative bacilli (enhanced activity), including P aeruginosa (similar to ceftazidime), and some AmpC beta-lactamase-producing Enterobacterales, such as Enterobacter species Table Fifth-generation cephalosporins The 5th-generation cephalosporins ceftaroline and ceftobiprole are active against Methicillin-resistant S aureus (MRSA) Penicillin-resistant streptococci Ampicillin - susceptible and beta-lactamase-producing Enterococcus faecalis Their activity against other gram-positive cocci and gram-negative bacilli is similar to that of 3rd-generation cephalosporins.