omadacycline and Neutropenia

Topics: Animals; Anti-Bacterial Agents; Disease Models, Animal; Methicillin-Resistant Staphylococcus aureus; Mice; Microbial Sensitivity Tests; Neutropenia; Staphylococcal Infections; Tetracyclines; Thigh

Utilizing a fully synthetic route to tetracycline analogues, the C-9 side-chain of the fluorocyclines was optimized for both antibacterial activity and oral efficacy. Compounds were identified that overcome both efflux (tet(K), tet(A)) and ribosomal protection (tet(M)) tetracycline-resistance mechanisms and are active against Gram-positive and Gram-negative organisms. A murine systemic infection model was used as an oral efficacy screen to rapidly identify compounds with oral bioavailability. Two compounds were identified that exhibit both oral bioavailability in rat and clinically relevant bacterial susceptibility profiles against major respiratory pathogens. One compound demonstrated oral efficacy in rodent lung infection models that was comparable to marketed antibacterial agents.

Topics: Administration, Oral; Animals; Anti-Bacterial Agents; Biological Availability; Cyclophosphamide; Drug Resistance, Multiple, Bacterial; Female; Gram-Negative Bacteria; Gram-Positive Bacteria; Lung; Male; Mice; Mice, Inbred BALB C; Microbial Sensitivity Tests; Neutropenia; Rats; Rats, Sprague-Dawley; Respiratory Tract Infections; Ribosomes; Sepsis; Stereoisomerism; Structure-Activity Relationship; Tetracycline Resistance; Tetracyclines