Eravacycline (TP-434, Xerava) is a synthetic halogenated tetracycline class antibiotic by Tetraphase Pharmaceuticals. It is closely related to tigecycline. It has a broad spectrum of activity including many multi-drug resistant strains of bacteria. Phase III studies in complicated intra-abdominal infections (cIAI) and complicated urinary tract infections (cUTI) were recently completed with mixed results. Eravacycline was granted fast track designation by the FDA and is currently available in USA. Medical uses
Eravacycline has shown broad spectrum of activity against a variety of Gram-positive and Gram-negative bacteria, including multi-drug resistant strains, such as methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Enterobacteriaceae. It is currently being formulated as for intravenous and oral administration. Spectrum of activity
Gram-positive organisms
Staphylococcus aureus (both methicillin-resistant and sensitive strains)
Streptococcus pneumoniae
Enterococcus faecalis
Enterococcus faecium (including vancomycin resistant strains)

Gram-negative organisms
Acinetobacter baumannii
Stenotrophomonas maltophilia
Haemophilus influenzae
Moraxella catarrhalis
Neisseria gonorrhoeae
Enterobacteriaceae
Escherichia coli (including ESBL-producing strains)
Klebsiella pneumoniae (including carbapenem resistant strains)
Klebsiella oxytoca
Enterobacter species
Citrobacter species
Proteus mirabilis
Serratia marcescensSimilar to other tetracycline derivatives, eravacycline is poorly active against Pseudomonas aeruginosa with a MIC90 = 16 mcg/mL (range 0.06-64 mcg/mL). Eravacycline maintains in-vitro activity against Enterobacteriaceae carrying the mcr-1 gene responsible for polymyxin b/colistin resistance. Clinical trials
Current and past clinical trial information:
https://clinicaltrials.gov/ct2/results?cond=&term=eravacycline&cntry1=&state1=&recrs=

Phase 3 trials
Complicated Intra-abdominal infections (IGNITE 1)
The IGNITE 1 trial compared twice-daily IV eravacycline to once-daily ertapenem for the treatment of cIAI. A total of 541 patients were included and eravacycline demonstrated noninferiority to ertapenem. An additional pivotal phase 3 study (IGNITE 4) is planned for late 2016 with initial results likely available in the fourth quarter of 2017.
Complicated Intra-abdominal Infections (IGNITE 4)
IGNITE 4 assessed twice-daily intravenous eravacycline(1.0 mg/kg every 12 hours) compared to those receiving meropenem (1g every 8 hours). The study enrolled 500 adult patients with the primary endpoint being clinical response at the test-of-cure visit which is 25–31 days after initial dosing. Primary efficiency analysis was conducted using a 12.5% non-inferiority margin in the microbiological intent-to-treat (micro-ITT) population. On July 25, 2017, Tetraphase pharmaceuticals released top line data via press showing clinical cure rates in the micro-ITT population to be 90.8% and 91.2% for eravacycline (n=195) and meropenem (n=205), respectively (95% CI: -6.3%,5.3%). Primary analysis was conducted using a 12.5% non-inferiority margin of the modified intent-to-treat (MITT) and clinically evaluable (CE) patient populations. Clinical cure rates in the MITT population were 92.4% and 91.6% for eravacycline (n=250) and meropenem (n=249), respectively (95% CI: -4.1%,5.8%). Clinical cure rates in the CE population were 96.9% and 96.1% for eravacycline (n=225) and meropenem (n=231), respectively (95% CI: -2.9%,4.5%). Eravacycline met the primary efficacy endpoints according to the FDA and EMA guidelines. The secondary analyses were consistent with, and supportive of, the primary outcome according to Tetraphase. There were no treatment-related serious adverse events (SAEs) in the trial. Treatment-emergent adverse event (TEAEs) rates were similar in both treatment groups with the most commonly reported drug-related adverse events (AEs) for eravacycline were infusion site reactions, nausea and vomiting, each occurring at a rate of less than 5%. The most common Gram-negative pathogens in the study included Escherichia coli, Klebsiella pneumoniae, Pseudomonas and Bacteroides.