Validation of a sensitive LC/MS/MS method for the determination of telaprevir and its R-isomer in human plasma.
The purpose of this study was to validate a reversed-phase high-performance liquid chromatographic (HPLC), tandem mass spectrometry (MS/MS) assay for the determination of telaprevir and its R-diastereomer (VRT-127394) in acidified and nonacidified human plasma. The chromatographic baseline separation of telaprevir and telaprevir-R was performed on a Waters XBridge(TM) BEH Shield C18 , 2.1 × 75 mm column with a 2.5 µm particle size, under isocratic conditions consisting of a mobile phase of 50:45:5 water-acetonitrile-isopropanol with 1% ammonia at 0.2 mL/min. This method utilized a stable isotope internal standard with 11 deuterium atoms on the structure of the telaprevir molecule (telaprevir-d11). An internal standard for the telaprevir-R (telaprevir-R-d11) was also prepared by incubating telaprevir-d11 in basic solution, which facilitated isomer inter-conversion. The detection and quantitation of telaprevir, telaprevir-R, telaprevir-IS and telaprevir-R-IS was achieved by positive ion electrospray (ESI+) MS/MS detection. The assay quantifiable limit was 5.0 ng/mL when 0.100 mL of acidified human plasma was extracted. Accuracy and precision were validated over the calibration range of 5.0-5000 ng/mL. It was demonstrated using patient samples that, contrary to previous recommendations, quantitation of telaprevir does not require acidified plasma.
University of Colorado Denver, School of Pharmacy, Department of Pharmaceutical Sciences, Aurora, Colorado, USA.
Xinhui
X
Chen
Lane R
LR
Bushman
Kevin J
KJ
McAllister
Peter L
PL
Anderson
Jennifer J
JJ
Kiser
D000998:Antiviral Agents / Q000097:blood* / Q000737:chemistry / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004355:Drug Stability; D006526:Hepatitis C / Q000188:drug therapy; D006801:Humans; D016018:Least-Squares Analysis; D009842:Oligopeptides / Q000097:blood* / Q000737:chemistry / Q000627:therapeutic use; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
D000998:Antiviral Agents; D009842:Oligopeptides; C486464:telaprevir
LC/MS/MS; analytical methodology; clinical pharmacology; hepatitis C virus; telaprevir