modithromycin

Modithromycin is a novel 6,11-bridged bicyclolide antibiotic, a member of the macrolide-lincosamide-streptogramin (MLS) class, developed by Enanta Pharmaceuticals. It was specifically engineered to overcome common mechanisms of macrolide resistance, such as those found in *Streptococcus pneumoniae* (e.g., erm-mediated methylation and mef-mediated efflux). Modithromycin exerts its antibacterial effect by binding to the 23S rRNA of the 50S ribosomal subunit, thereby inhibiting bacterial protein synthesis. Clinical development focused on respiratory tract infections, including community-acquired pneumonia (CAP), acute bacterial exacerbation of chronic bronchitis, and acute bacterial sinusitis. Although it reached Phase 2 clinical trials and demonstrated a favorable safety profile, development was ultimately discontinued by Enanta and its partner Shionogi.

Other names

modithromycin