Comparative in-vitro activities of A-56268 (TE-031) and erythromycin against 306 clinical isolates.
The inhibitory (MIC) and bactericidal (MBC) activities of a new macrolide A-56268 (TE-031) against 306 clinical aerobic bacterial isolates was compared with that of erythromycin. The MIC90/MBC90 ratios for A-56268 were: Campylobacter jejuni 4/16, Haemophilus influenzae 8/8-16, H. parainfluenzae 8/8-16, Legionella pneumophila 0.06/0.5, methicillin-sensitive isolates of Staphylococcus aureus 0.5/1, and coagulase negative staphylococci 1/8, methicillin resistant isolates of Staph. aureus and coagulase negative staphylococci greater than 16/ greater than 16, Streptococcus pneumoniae 0.06/0.125, streptococcus Group A 0.06/2-4, streptococcus Group B 0.06/8- greater than 16, streptococcus Groups C and G 0.125/8 and Str. faecalis 4/64. Compared with erythromycin, A-56268 had greater inhibitory and bactericidal activity against isolates of L. pneumophila, with an MIC90 16-fold less and an MBC90 eight-fold less than that of erythromycin. Except for enterococci, A-56268 showed inhibitory activity equal to or greater than that of penicillin G against isolates of streptococci and an MIC two-fold less than that of erythromycin. For other strains tested, the inhibitory and bactericidal activities of A-56268 and erythromycin were similar. The clinical importance of the differences between these two macrolides will depend on the pharmacokinetic and tissue penetration properties of the new compound.
Liebers
D M
DM
Department of Medicine, Veterans Administration Medical Center, Albany, New York 12208.
Baltch
A L
AL
Smith
R P
RP
Hammer
M C
MC
Conroy
J V
JV
Shayegani
M
M
D001420:Bacteria, Aerobic / Q000187:drug effects*; D017291:Clarithromycin; D004917:Erythromycin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests
D004917:Erythromycin; D017291:Clarithromycin