In vitro activity of eravacycline compared to other antibiotics commonly used for treatment of infections involving anaerobic bacteria: a review of the literature and our own data.

Eravacycline is a third-generation tetracycline, a fluorocycline agent with two modifications that distinguish it from tigecycline. Eravacycline demonstrated effectiveness against various gram-positive and gram-negative facultatively anaerobic bacteria, including multidrug resistant Enterobacterales, Acinetobacter baumannii, staphylococci, enterococci, and pneumococci. However, whereas numerous studies focused on the impact of eravacycline on facultative anaerobic microbes, there is limited data regarding its efficacy against anaerobes. The aim of the present review was to compare eravacycline activity to that of other antibiotics used against anaerobic/microaerophilic bacteria and to assess potential benefits of the newer agent in anaerobic or mixed aerobic-anaerobic infections. We encompassed information from the literature published in English and included our own pilot study. Compared to most comparator antibiotics, eravacycline was more effective against anaerobes, including Bacteroides/Parabacteroides, Prevotella, Fusobacterium, Clostridioides difficile and other clostridial species, as well as gram-positive anaerobic cocci, and Cutibacterium acnes. Most frequently, eravacycline MICs were ≥4 to ≥8-fold lower than those of most comparator antibiotics. In addition, eravacycline did not trigger an infection with C. difficile and is considered a tolerable medication. So far, only the injectable eravacycline administration for complicated intraabdominal infections has been approved. However, more studies in more countries are needed to assess its usefulness for combination treatment and still not labeled indications.