title: Quantification and stability of everolimus (SDZ RAD) in human blood by high-performance liquid chromatography-electrospray tandem mass spectrometry.
abstract: We report here a validated method for the quantification of a new immunosuppressant drug, everolimus (SDZ RAD), using HPLC-tandem mass spectrometry. Whole blood samples (500 microl) were prepared by protein precipitation, followed by C(18) solid-phase extraction. Mass spectrometric detection was by selected reaction monitoring with an electrospray interface operating in positive ionization mode. The assay was linear from 0.5 to 100 microg/l (r(2) > 0.996, n = 9). The analytical recovery and inter-day imprecision, determined using whole blood quality control samples (n = 5) at 0.5, 1.2, 20.0, and 75.0 microg/l, was 100.3 - 105.4% and < or = 7.6%, respectively. The assay had a mean relative recovery of 94.8 +/- 3.8%. Extracted samples were stable for up to 24 h. Fortified everolimus blood samples were stable at -80 degrees C for at least 8 months and everolimus was found to be stable in blood when taken through at least three freeze-thaw cycles. The reported method provides accurate, precise and specific measurement of everolimus in blood over a wide analytical range and is currently supporting phase II and III clinical trials.
authors: Australian Bioanalytical Services Pty Ltd., First Floor Lions Research Building, Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Queensland 4102, Brisbane, Australia. ausbio@hotmail.com
authors: Paul
authors: P
authors: Salm
authors: Paul J
authors: PJ
authors: Taylor
authors: Stephen V
authors: SV
authors: Lynch
authors: Peter I
authors: PI
authors: Pillans
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D000068338:Everolimus; D006801:Humans; D007166:Immunosuppressive Agents / Q000097:blood*; D012015:Reference Standards; D015203:Reproducibility of Results; D020123:Sirolimus / Q000031:analogs & derivatives* / Q000097:blood*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D007166:Immunosuppressive Agents; C514512:SDZ RAD 223-756; D000068338:Everolimus; D020123:Sirolimus