Ceftaroline, a 5th-generation cephalosporin approved for MRSA, differs from earlier cephalosporins in which key property?

• A It inhibits beta-lactamase enzymes in addition to binding PBPs
• B It is orally bioavailable, unlike older injectable cephalosporins
• C It acts as a bacteriostatic agent in contrast to bactericidal older cephalosporins
• D It has a unique side chain enabling binding to PBP2a (MRSA PBP), unlike older cephalosporins ✓

Explanation

Ceftaroline's unique pyrrolidine substituent at the 3-position and aminothiazolyl group at C-7 enable it to bind PBP2a (the MRSA resistance target) with sufficient affinity to inhibit peptidoglycan cross-linking even in mecA-positive MRSA. Older cephalosporins cannot fit the active site of PBP2a. It does not inhibit beta-lactamases (it requires beta-lactamase inhibitor avibactam for ESBL coverage), is not orally available, and is bactericidal like all beta-lactams.

Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.