title: A solid phase extraction-liquid chromatographic-tandem mass spectrometry method for determination of concentrations of GDC-0941, a small molecule class I phosphatidylinositide 3-kinase inhibitor, to support clinical development.
abstract: A solid phase extraction (SPE) liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method for the determination of GDC-0941 concentrations in human plasma has been developed and validated to support clinical development. An Oasis MCX 10mg 96-well SPE plate was used to extract plasma samples (50 μL) and the resulting extracts were analyzed using reverse-phase chromatography and mass spectrometer coupled with a turbo-ionspray interface. The method was validated over the calibration curve range 0.500-500 ng/mL with linear regression and 1/x(2) weighting. Within-run relative standard deviation (%RSD) ranged from 1.5 to 11.5%, while the between-run %RSD varied from 0.0 to 4.4%. The accuracy ranged from 96.0% to 110.0% of nominal for within-run and 98.0% to 108.0% of nominal for between-run at all concentrations including the LLOQ quality control at 0.500 ng/mL. Extraction recovery of GDC-0941 was between 79.0% and 86.2%. Stability of GDC-0941 was established in human plasma for 602 days at -70 °C and 598 days at -20°C, respectively, and established in reconstituted sample extracts for 167 h when stored at room temperature. Internal standard normalized matrix factor was 1.1, demonstrating that the use of the stable-labeled internal standard GDC-0941-d(8) effectively compensated observed matrix effect and resulting in no adverse impact on the quality of the data produced. This assay was used for the determination of GDC-0941 human plasma concentrations over a sufficient time period to determine pharmacokinetic parameters at relevant clinical doses.
authors.affiliation: Genentech, Drug Metabolism and Pharmacokinetics, MS 412A, 1 DNA Way, South San Francisco, CA 94080, United States. ding.xiao@gene.com
authors.forename: X
authors.initials: X
authors.lastname: Ding
authors.forename: G
authors.initials: G
authors.lastname: Morrison
authors.forename: B
authors.initials: B
authors.lastname: Dean
authors.forename: C E C A
authors.initials: CE
authors.lastname: Hop
authors.forename: L
authors.initials: L
authors.lastname: Tobler
authors.forename: S
authors.initials: S
authors.lastname: Percey
authors.forename: M
authors.initials: M
authors.lastname: Meng
authors.forename: S
authors.initials: S
authors.lastname: Reuschel
authors.forename: D A
authors.initials: DA
authors.lastname: West
authors.forename: S
authors.initials: S
authors.lastname: Holden
authors.forename: J A
authors.initials: JA
authors.lastname: Ware
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D005260:Female; D006801:Humans; D007191:Indazoles / Q000097:blood*; D008297:Male; D058539:Phosphatidylinositol 3-Kinase / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D015203:Reproducibility of Results; D052616:Solid Phase Extraction / Q000379:methods*; D013449:Sulfonamides / Q000097:blood*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: C532162:2-(1H-indazol-4-yl)-6-(4-methanesulfonylpiperazin-1-ylmethyl)-4-morpholin-4-ylthieno(3,2-d)pyrimidine; D007191:Indazoles; D000081082:Phosphoinositide-3 Kinase Inhibitors; D013449:Sulfonamides; D058539:Phosphatidylinositol 3-Kinase