Effects of Different Component Contents of Colistin Methanesulfonate on the Pharmacokinetics of Prodrug and Formed Colistin in Human

To evaluate the effects of component contents in different colistin methanesulfonate (CMS) formulas on their clinical pharmacokinetics of the prodrug CMS and the formed colistin.Two CMS formulas (CTTQ and Parkedale) were investigated in a single dose, randomized, open-label, crossover study conducted in 18 healthy Chinese subjects. Both CMS formulas met the requirements of European Pharmacopoeia 9.2 with 12.1% difference in the two major active components (CMS A and CMS B). The PK parameters after a single intravenous infusion of CMS at 2.5 mg/kg were calculated and the steady-state plasma colistin concentrations (CThe systemic exposure (AUCThe difference in component content in the two CMS formulas had a significant (P 0.001) impact on the systemic exposure of colistin in human, thus, warranted essential considerations in clinical applications.