Short-term Safety, Tolerability, and Pharmacokinetics of MRX-I, an Oxazolidinone Antibacterial Agent, in Healthy Chinese Subjects

• Published in: Clinical therapeutics Vol. 40; no. 2; pp. 322 - 332.e5
• Main Authors: Wu, Xiaojie, Li, Yunfei, Zhang, Jing, Zhang, Yingyuan, Yu, Jicheng, Cao, Guoying, Chen, Yuancheng, Guo, Beining, Shi, Yaoguo, Huang, Jun, Cao, Yuran, Liu, Xiaofang, Wu, Jufang, Gordeev, Mikhail Fedorovich, Yuan, Hong, Wang, Wen
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.02.2018; Elsevier Limited
• Subjects: Antimicrobial agents; Blood & organ donations; Clinical trials; Drug dosages; Enzymes; Food; healthy subjects; Hepatitis; Internal Medicine; Monte Carlo simulation; MRX-I; Pharmacokinetics; Population; safety; Software; Staphylococcus aureus; Staphylococcus infections; Streptococcus infections; Urine; United States > US; Massachusetts; California; pharmacokinetics; MRX-I; healthy subjects; safety
• ISSN: 0149-2918; 1879-114X; 1879-114X
• DOI: 10.1016/j.clinthera.2017.12.017

This study was designed to evaluate the safety and pharmacokinetic profiles of MRX-I tablet, an oxazolidinone antibacterial agent, in healthy Chinese subjects. The study was composed of 3 sequential periods. Period 1 was a randomized, double-blind, placebo-controlled, sequential ascending dose (50 to 1800 mg) study. Period 2 included one arm as a randomized, open-label, 3-period, 3 × 3 Latin square single-dose study of 300, 600, and 900 mg MRX-I administration and another arm as a crossover study to evaluate high-fat diet effect. Period 3 was a randomized, double-blind, placebo-controlled multiple-dose study with 600 or 800 mg, q12h regimens over 15 days. MRX-I was rapidly absorbed and reached peak plasma concentration at about 2 hours post dose. The Cmax was 8.07, 12.24, and 15.25 mg/L and the corresponding AUC0−∞ 29.21, 48.27, and 59.60 mg/h/L, in 300-, 600-, and 900-mg dosing groups, respectively. High-fat diet increased the exposure of MRX-I. No discernable drug accumulation was observed after 15 days of continuous drug administration. About 2% of MRX-I was excreted via kidneys in unchanged form. No obvious hematologic toxicity by MRX-I was observed during the entire study. Based on Monte Carlo simulation, 600 or 800 mg BID can produce satisfactory efficacy against methicillin-resistant Staphylococcus aureus. MRX-I was well tolerated in healthy Chinese subjects (50–1800 mg). No serious or severe adverse effects were observed. MRX-I 600 or 800 mg BID up to 15 days can be recommended in future clinical trials. Chinese Clinical Trial Registration (http://www.chinadrugtrials.org.cn) identifier: CTR20131214.