Eravacycline  Eravacycline (TP-434, Xerava) is a synthetic halogenated tetracycline class antibiotic in development 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 has been granted fast track designation by the FDA. 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. Similar to other tetracycline derivatives, eravacylcine 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. Current and past clinical trial information: https://clinicaltrials.gov/ct2/results?cond=&term=eravacycline&cntry1=&state1=&recrs=  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. 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.