This is one of two phase 3, double-blind, randomised clinical trials of omadacycline in the New England Journal of Medicine. The other one involved patients with acute bacterial skin and skin-structure infections.
According to an editorial, there are several effective treatment options for community-acquired bacterial pneumonia although omadacycline may offer some advantages, in that addition to having activity against typical bacterial respiratory pathogens, it is active against the atypical organisms Legionella pneumophila, Mycoplasma pneumoniae, and Chlamydia pneumoniae, whereas beta-lactams are not. It suggests that omadacycline is a single-agent alternative, either parenteral or oral, to empirical beta-lactam–macrolide combination therapy or a respiratory fluoroquinolone for community-acquired bacterial pneumonia. It adds however that the use of omadacycline for the treatment of community-acquired bacterial pneumonia is considered, it is important to remember that patients with hemodynamic instability, septic shock, clinically significant immunologic deficiency, or infection with a suspected drug-resistant pathogen (e.g., fluoroquinolone-resistant Klebsiella pneumoniae) were excluded from the trial. In addition, there was an imbalance in mortality: eight deaths in the omadacycline group as compared with four in the moxifloxacin group. The reasons for this imbalance are unclear, but death occurred disproportionately among patients with a Pneumonia Severity Index risk class of IV (classes range from I to IV, with higher classes indicating a higher risk of death).
The editorial also discusses the role of omadacycline for treatment of infections caused by multiple-drug–resistant pathogens. It notes that it does not have cross-resistance with beta-lactam antibiotics, aminoglycosides, polymyxins, and fluoroquinolones and is active against organisms expressing tetracycline efflux and ribosomal protection genes. Also it is many times more active than doxycycline and minocycline against Enterobacteriaceae and Acinetobacter baumannii. It calls for well-designed clinical trials of omadacycline for the treatment of infections caused by multiple-drug–resistant gram-negative pathogens to determine its real value as an antibacterial agent.
Omadacycline was approved in the US for the treatment of adults with acute skin and skin structure infections or community-acquired bacterial pneumonia in 2018. A licensing application was been submitted to the European Medicines Agency in October 2018.