Omadacycline
In Summer 2020, the Pharmacy and Therapeutics Committee voted to add IV and oral omadacycline to the formulary at Nebraska Medicine. Its use is currently restricted to prescribers from Infectious Diseases services only.
Efficacy
Omadacycline is a tetracycline with a unique chemical structure that allows it to overcome resistance mechanisms used against doxycycline and minocycline, including drug efflux and ribosomal protection. It has activity against vancomycin-resistant Enterococcus (VRE), carbapenem-resistant Acinetobacter baumannii (CRAB) and extended-spectrum beta-lactamase-producing organisms (ESBL’s). It also has in vitro activity against rapidly-growing Mycobacterium spp. Clinical trials have found omadacycline to be noninferior to ertapenem and meropenem in the treatment of community-acquired bacterial pneumonia and noninferior to linezolid in the treatment of acute bacterial skin and skin structure infections, leading to its FDA-approved indications for these infections.
Safety
Clinical trials have shown omadacycline to be well-tolerated, with rates of nausea and vomiting much lower than tigecycline. The majority of adverse effects reported in clinical trials were classified as mild to moderate and did not result in drug discontinuation. Another potential adverse effect associated with omadacycline is hepatotoxicity in the form of increased transaminases, alkaline phosphatase, and total bilirubin; however, these effects are rare with an incidence typically <5%.
Uniqueness
Omadacycline’s enhanced antibacterial spectrum, lack of significant resistance, decreased adverse effects, and availability in an oral dosage form give it a niche role in the treatment of community-acquired infections, especially those caused by multidrug-resistant organisms. It also provides an additional oral option for the treatment of rapidly-growing mycobacterial infections.