Sequence 1
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Eravacycline is an antibacterial drug [see Microbiology ( 12.4 )]. 12.2 Pharmacodynamics The AUC divided by the MIC of eravacycline has been shown to be the best predictor of activity. Based on the flat exposure-response relationship observed in clinical studies, eravacycline exposure achieved with the recommended dosage regimen appears to be on the plateau of the exposure-response curve. Cardiac Electrophysiology The effect of XERAVA on the QTc interval was evaluated in a Phase 1 randomized, placebo and positive controlled, double-blind, single-dose, crossover thorough QTc study in 60 healthy adult subjects. At the 1.5 mg/kg single dose (1.5 times the maximum approved recommended dose), XERAVA did not prolong the QTc interval to any clinically relevant extent. 12.3 Pharmacokinetics Following single-dose intravenous administration, eravacycline AUC and Cmax increase approximately dose-proportionally over doses from 1 mg/kg to 3 mg/kg (3 times the approved dose). The mean exposure of eravacycline after single and multiple intravenous infusions (approximately 60 minutes) of 1 mg/kg administered to healthy adults every 12 hours is presented in Table 2. There is approximately 45% accumulation following intravenous dosing of 1 mg/kg every 12 hours. Table 2: Mean (%CV) Plasma Exposure of Eravacycline After Single and Multiple Intravenous Dose in Healthy Adults Exposure [Arithmetic Mean (%CV)] C max (ng/mL) AUC 0-12 (ng∙h/mL) Abbreviations: C max = maximum observed plasma concentration, CV = coefficient of variation; AUC 0-12 = area under the plasma concentration-time curve from time 0 to 12 hours. Day 1 2125 (15) 4305 (14) AUC of day 1 equals AUC 0-12 after the first dose of eravacycline. Day 10 1825 (16) 6309 (15) AUC of day 10 equals steady state AUC 0-12 . Distribution Protein binding of eravacycline to human plasma proteins increases with increasing plasma concentrations, with 79% to 90% (bound) at plasma concentrations ranging from 100 to 10,000 ng/mL. The volume of distribution at steady-state is approximately 321 L. Elimination The mean elimination half-life is 20 hours. Metabolism Eravacycline is metabolized primarily by CYP3A4- and FMO-mediated oxidation. Excretion Following a single intravenous dose of radiolabeled eravacycline 60 mg, approximately 34% of the dose is excreted in urine and 47% in feces as unchanged eravacycline (20% in urine and 17% in feces) and metabolites. Specific Populations No clinically significant differences in the pharmacokinetics of eravacycline were observed based on age (18-86 years), sex, and race. Patients with Renal Impairment The geometric least square mean Cmax for eravacycline was increased by 8.8% for subjects with end stage renal disease (ESRD) versus healthy subjects with 90% CI -19.4, 45.2. The geometric least square mean AUC0-inf for eravacycline was decreased by 4.0% for subjects with ESRD versus healthy subjects with 90% CI -14.0, 12.3 [see Use in Specific Populations ( 8.7 )] . Patients with Hepatic Impairment Eravacycline C max was 13.9%, 16.3%, and 19.7% higher in subjects with mild (Child-Pugh Class A), moderate (Child-Pugh Class B), and severe (Child‑Pugh Class C) hepatic impairment versus healthy subjects, respectively. Eravacycline AUC 0-inf was 22.9%, 37.9%, and 110.3% higher in subjects with mild, moderate, and severe hepatic impairment versus healthy subjects, respectively [see Dosage and Administration ( 2.2 ) and Use in Specific Populations ( 8.6 )] . Drug Interaction Studies Clinical Studies Concomitant use of rifampin (strong CYP3A4/3A5 inducer) decreased eravacycline AUC by 35% and increased eravacycline clearance by 54% [see Dosage and Administration ( 2.3 ) and Drug Interactions ( 7.1 )] . Concomitant use of itraconazole (strong CYP3A inhibitor) increased eravacycline C max by 5% and AUC 0-t by 32%, and decreased eravacycline clearance by 32%. In Vitro Studies Eravacycline is a substrate for the transporters P-gp, organic anion transporter peptide OATP1B1 and OATP1B3 Eravacycline is not a substrate for breast cancer resistance protein (BCRP), bile salt export pump (BSEP), organic ion transporter (OAT)1, OAT3, OCT1, OCT2, multidrug and toxin extrusion (protein) (MATE)1, or MATE2-K transporters. Eravacycline is not an inhibitor of BCRP, BSEP, OATP1B1, OATP1B3, OAT1, OAT3, OCT1, OCT2, MATE1, or MATE2-K transporters. Eravacycline is not an inhibitor of CYP1A2, 2B6, 2C8, 2C9, 2C19, 2D6, or 3A4/5. Eravacycline is not an inducer of CYP1A2, 2B6, or 3A4. 12.4 Microbiology Mechanism of Action Eravacycline is a fluorocycline antibacterial within the tetracycline class of antibacterial drugs. Eravacycline disrupts bacterial protein synthesis by binding to the 30S ribosomal subunit thus preventing the incorporation of amino acid residues into elongating peptide chains. In general, eravacycline is bacteriostatic against gram-positive bacteria (e.g., Staphylococcus aureus and Enterococcus faecalis ); however, in vitro bactericidal activity has been demonstrated against certain strains of Escherichia coli and Klebsiella pneumoniae . Resistance Eravacycline resistance in some bacteria is associated with upregulated, non-specific intrinsic multidrug-resistant (MDR) efflux, and target-site modifications such as to the 16s rRNA or certain 30S ribosomal proteins (e.g., S10). The C7 and C9 substitutions in eravacycline are not present in any naturally occurring or semisynthetic tetracyclines and the substitution pattern imparts microbiological activities including in vitro activity against gram-positive and gram-negative strains expressing certain tetracycline-specific resistance mechanism(s) [i.e., efflux mediated by tet (A), tet (B), and tet (K); ribosomal protection as encoded by tet (M) and tet (Q)]. Activity of eravacycline was demonstrated in vitro against Enterobacteriaceae in the presence of certain beta-lactamases, including extended spectrum β-lactamases, and AmpC. However, some beta-lactamase-producing isolates may confer resistance to eravacycline via other resistance mechanisms. The overall frequency of spontaneous mutants in the gram-positive organisms tested was in the range of 10 -9 to 10 -10 at 4 times the eravacycline Minimum Inhibitory Concentration (MIC). Multistep selection of gram-negative strains resulted in a 16- to 32-times increase in eravacycline MIC for one isolate of Escherichia coli and Klebsiella pneumoniae , respectively. The frequency of spontaneous mutations in K. pneumoniae was 10 -7 to 10 ‑8 at 4 times the eravacycline MIC. Interaction with Other Antimicrobials In vitro studies have not demonstrated antagonism between XERAVA and other commonly used antibacterial drugs for the indicated pathogens. Antimicrobial Activity XERAVA has been shown to be active against most isolates of the following microorganisms, both in vitro and in clinical infections [see Indications and Usage ( 1 )] : Aerobic bacteria Gram-positive bacteria Enterococcus faecalis Enterococcus faecium Staphylococcus aureus Streptococcus anginosus group Gram-negative bacteria Citrobacter freundii Enterobacter cloacae Escherichia coli Klebsiella oxytoca Klebsiella pneumoniae Anaerobic bacteria Gram-positive bacteria Clostridium perfringens Gram-negative bacteria Bacteroides caccae Bacteroides fragilis Bacteroides ovatus Bacteroides thetaiotaomicron Bacteroides uniformis Bacteroides vulgatus Parabacteroides distasonis The following in vitro data are available, but their clinical significance is unknown. At least 90 percent of the following bacteria exhibit an in vitro minimum inhibitory concentration (MIC) less than or equal to the susceptible breakpoint for eravacycline against isolates of similar genus or organism group. However, the efficacy of eravacycline in treating clinical infections caused by these bacteria has not been established in adequate and well-controlled clinical trials. Aerobic bacteria Gram-positive bacteria Streptococcus salivarius group Gram-negative bacteria Citrobacter koseri Enterobacter aerogenes Susceptibility Test Methods For specific information regarding susceptibility test interpretive criteria, and associated test methods and quality control standards recognized by FDA for this drug, please see https://www.fda.gov/STIC.