Eravacycline Exhibits 'Excellent' In Vitro Activity Against Enterobacteriaceae, Study Reports

In August of 2018 the US Food and Drug Administration approved eravacycline (XERAVA) for the treatment of complicated intra-abdominal infections in adults 18 years and older.

“[Eravacycline is] a fluorocycline-type tetracycline. This drug is active against resistant Enterobacteriaceae and some gram-positive organisms as well,” explained Jason Gallagher, PharmD, clinical professor at Temple University School of Pharmacy and editor-in-chief of Contagion^®, in an interview about the agent, “It’s fairly broad in its spectrum; it does not have activity against Pseudomonas similar to tigecycline or the other tetracyclines.”

In new research, investigators set out to determine the in vitro activity of eravacycline and its comparators against European gram-negative clinical isolates collected in 2017.

The findings of the study were presented in a poster presentation at the European Congress for Clinical Microbiology and Infectious Diseases (ECCMID 2019).

Eravacycline is described as fully-synthetic fluorocycline antibacterial that is also approved in the European Union. The agent retains activity against common tetracycline-specific acquired resistance mechanisms (efflux and ribosomal protection) and has shown activity against a broad range of gram-negative, gram-positive, and anaerobic organisms.

A total of 1171 non-duplicate, non-consecutive, single-patient Enterobacteriaceae isolates and 222 Acinetobacter baumannii isolates were collected from multiple infection sources from health systems throughout Europe for the ongoing multi-infection surveillance study. The investigators determined minimum inhibitory concentrations (MICs) by CLSI broth microdilution.

The abstract indicates that for the 1171 Enterobacteriaceae isolates, eravacycline’s activity was 0.25 for MIC₅₀, 1.0 for MIC₉₀, 0.06 for MIN MIC, and 16.0 for MAX MIC, compared with tigecycline activity, which was 0.5 for MIC₅₀, 2.0 for MIC₉₀, 0.12 for MIN MIC, and 32.0 for MAX MIC.

Furthermore, for the 222 Acinetobacter baumannii isolates, eravacycline’s activity was 0.25 for MIC₅₀, 0.5 for MIC₉₀, <0.015 for MIN MIC, 2.0 for MAX MIC, compared with tigecycline activity, which was 2.0 for MIC₅₀, 4.0 for MIC₉₀, 0.06 for MIN MIC, and 16.0 for MAX MIC.

The investigators conclude that, based on the MIC data for eravacycline and tigecycline, eravacycline exhibited “excellent” in vitro activity against the vast majority of Enterobacteriaceae, “including isolates that produced ESBL and was 2-4-fold more active than tigecycline. Against A baumannii, eravacycline was at least 8-fold more active than tigecycline.”

The study, “Surveillance of the in vitro activity of eravacycline and comparators against clinical isolates from Europe during 2017,” was presented in an oral abstract presentation on April 15, 2019, at ECCMID 2019 in Amsterdam, the Netherlands.