title: Reliable LC-MS/MS assay for the estimation of rilpivirine in human plasma: application to a bioequivalence study and incurred sample reanalysis.
abstract: A simple, precise, and rapid stable isotope dilution liquid chromatography-tandem mass spectrometry method has been developed and validated for the quantification of rilpivirine, a non-nucleoside reverse transcriptase inhibitor in human plasma. Rilpivirine and its deuterated analogue, rilpivirine-d6, used as an internal standard (IS) were quantitatively extracted by liquid-liquid extraction with methyl-tert-butyl ether and diethyl ether solvent mixture from 50 μL plasma. The chromatography was achieved on Gemini C18 (150 × 4.6 mm, 5 µm) analytical column in a run time of 2.2 min. The precursor → product ion transitions for rilpivirine (m/z 367.1 → 128.0) and IS (m/z 373.2 → 134.2) were monitored on a triple quadrupole mass spectrometer in the positive ionization mode. The linearity of the method was established in the concentration range of 0.5-200 ng/mL. The mean extraction recovery for rilpivirine (94.9%) and IS (99.9%) from spiked plasma samples was consistent and reproducible. The IS-normalized matrix factors for rilpivirine ranged from 0.98 to 1.02 across three quality controls. Bench top, freeze-thaw, wet extract, and long-term stability of rilpivirine was examined in spiked plasma samples. The application of the method was demonstrated by a bioequivalence study with 25 mg rilpivirine tablet formulation in 40 healthy subjects. The assay reproducibility was shown by reanalysis of 200 study samples and the % change in the concentration of repeat values from the original values was within ±15%.
authors.affiliation: Chemistry Department, Kadi Sarva Vishwavidyalaya, Sarva Vidyalaya Campus, Sector 15/23, Gandhinagar, 382015, India; Bioanalytical Research Department, Veeda Clinical Research, Ambawadi, Ahmedabad, 380015, India.
authors.forename: Ajay
authors.initials: A
authors.lastname: Gupta
authors.forename: Swati
authors.initials: S
authors.lastname: Guttikar
authors.forename: Yogesh
authors.initials: Y
authors.lastname: Patel
authors.forename: Pranav S
authors.initials: PS
authors.lastname: Shrivastav
authors.forename: Mallika
authors.initials: M
authors.lastname: Sanyal
mesh_terms: D000293:Adolescent; D000328:Adult; D002853:Chromatography, Liquid / Q000379:methods*; D018592:Cross-Over Studies; D004355:Drug Stability; D064368:Healthy Volunteers; D006801:Humans; D059625:Liquid-Liquid Extraction / Q000379:methods; D008875:Middle Aged; D015203:Reproducibility of Results; D000068696:Rilpivirine / Q000097:blood* / Q000493:pharmacokinetics; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013810:Therapeutic Equivalency; D055815:Young Adult
chemical_list: D000068696:Rilpivirine
keywords: LC-MS/MS; bioequivalence study; human plasma; incurred sample reanalysis; rilpivirine