Omadacycline

Omadacycline can be either bacteriostatic or bacteriocidal depending on the organism involved. It disrupts bacterial protein synthesis without affecting DNA, RNA, or peptidoglycan synthesis. Omadacycline represents an improvement over existing tetracycline agents as it has not been found to be subject to tetracycline resistance mediated by tetracycline efflux pumps encoded by the tet(K), tet(L), and tet(B) or to ribosomal protection proteins encoded by tet(O) and tet(M). Omadacycline is susceptible to RNA mutations which confer resistance to tetracyclines.

Omadacycline binds to the primary tetracycline binding site on the bacterial 30s ribosomal subunit with high specificity. There it acts to block protein synthesis, disrupting many facets of cellular function and resulting in either cell death or stasis.

Omadacycline has an mean absolute oral bioavailability of 34.5% and a mean Tmax of2.5 h with oral dosing. With multiple dosing, Omadacycline displays an accumulation factor of 1.5. Official labeling states that food does not significantly impact rate or extent of absorption, however, conflicting data exists suggesting food may lower the bioavailability of omadacycline taken after eating. The exposure in alveolar cells and epithelial lining fluid is 25.8 and 1.5 fold higher than plasma exposure after IV administration, suggesting Omadacycline penetrates the lungs to a significant degree.

After IV dosing 27% of Omadacycline was eliminated by the kidneys. In oral dosing 14.4% was found to be eliminated by the kidneys and 81.1% in the feces. Neither renal nor hepatic impairment appears to produce a clinically relevant effect elimination.