ABSTRACT
Cethromycin (formerly ABT-773; Restanza) is a ketolide antibiotic whose development was initiated by Abbott in 1997 but abandoned in 2002. Since 2004 Advanced Life Sciences has promoted the development of cethromycin. The ketolides are structurally derived from erythromycin A and designed to overcome bacterial resistance to macrolides. One of the main features of the ketolide antibiotics is the absence of the neutral sugar L-cladinose at position 3 of the erythonolide ring, which is replaced by a keto group (thus giving rise to the antibiotic class name) (Zhanel et al., 2002). The absence of the L-cladinose moiety also results in better drug absorption and less gastric irritation through improved acid stability.
