RESUMO
Raltegravir (RAL) is a HIV-integrase inhibitor recommended for treatment of HIV type 1 infection during pregnancy. The elimination of RAL to RAL glucuronide (RAL GLU) is mediated primarily by UDP glucuronosyltransferase 1A1 (UGT1A1). The present study shows the development and validation of 4 different methods for the analysis of RAL and RAL GLU in plasma and in urine samples. The methods were applied to evaluate the maternal-fetal pharmacokinetics of RAL and RAL GLU in a HIV-infected pregnant woman receiving RAL 400â¯mg twice daily. The sample preparation for RAL and RAL GLU analysis in 25⯵L plasma and 100⯵L diluted urine (10-fold with water containing 0.1% formic acid) were carried out by protein precipitation procedure. RAL and RAL GLU generate similar product mass fragments and require separation in the chromatographic system, so a suitable resolution was achieved for unchanged RAL and RAL GLU employing Ascentis Express C18 (75â¯×â¯4.6â¯mm, 2.7⯵m) for both plasma and urine samples. The methods showed linearities at the ranges of 0.1-13.5⯵g/mL RAL and 0.15-19.5⯵g/mL RAL GLU in urine and 10-2000â¯ng/mL RAL and 2.5-800 RAL GLU in plasma. Precise and accurate evaluation showed coefficients of variation and relative errors ≤ 15%. The methods have been successfully applied in a maternal-fetal pharmacokinetic study.