title: Validation of an enantioselective LC-MS/MS method to quantify enantiomers of (±)-OTX015 in mice plasma: Lack of in vivo inversion of (-)-OTX015 to its antipode.
abstract: A highly sensitive, specific and enantioselective assay has been validated for the quantitation of OTX015 enantiomers [(+)-OTX015 and (-)-OTX015] in mice plasma on LC-MS/MS-electrospray ionization as per regulatory guidelines. Protein precipitation was used to extract (±)-OTX015 enantiomers and internal standard (IS) from mice plasma. The active [(-)-OTX015] and inactive [(+)-OTX015] enantiomers were resolved on a Chiralpak-IA column using an isocratic mobile phase (0.2% ammonia/acetonitrile 20 : 80, v/v) at a flow rate of 1.2 mL/min. The total run time was 6.0 min. (+)-OTX015, (-)-OTX015 and IS eluted at 3.34, 4.08 and 4.77 min, respectively. The MS/MS ion transitions monitored were m/z 492 → 383 for OTX015 and m/z 457 → 401 for IS. The standard curves for OTX015 enantiomers were linear (r2> 0.998) in the concentration range 1.03-1030 ng/mL. The inter- and intraday precisions were in the range 2.20-13.3 and 8.03-12.1% and 3.80-14.4 and 8.97-13.6% for (+)-OTX015 and (-)-OTX015, respectively. Both the enantiomers were found to be stable in a battery of stability studies. This novel method has been applied to the study of stereoselective oral pharmacokinetics of (-)-OTX015 and unequivocally demonstrated that (-)-OTX015 does not undergo chiral inversion to its antipode in vivo in mice.
authors.affiliation: Analytical Department, Jubilant Biosys Ltd, Bangalore, India.
authors.forename: Narayanan
authors.initials: N
authors.lastname: Balaji
authors.affiliation: Medicinal Chemistry Department, Jubilant Biosys Ltd, Bangalore, India.
authors.forename: Murugan
authors.initials: M
authors.lastname: Chinnapattu
authors.affiliation: Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Bangalore, India.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Dixit
authors.affiliation: Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Bangalore, India.
authors.forename: Promod
authors.initials: P
authors.lastname: Sahu
authors.affiliation: Drug Metabolism and Pharmacokinetics, Jubilant Biosys Ltd, Bangalore, India.
authors.forename: Suresh
authors.initials: S
authors.lastname: P S
authors.affiliation: Medicinal Chemistry Department, Jubilant Biosys Ltd, Bangalore, India.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Mullangi
mesh_terms: D000083:Acetanilides / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry* / Q000493:pharmacokinetics; D000284:Administration, Oral; D000818:Animals; D002138:Calibration; D002853:Chromatography, Liquid / Q000379:methods*; D004355:Drug Stability; D006575:Heterocyclic Compounds, 3-Ring / Q000008:administration & dosage / Q000097:blood* / Q000737:chemistry* / Q000493:pharmacokinetics; D008297:Male; D008807:Mice, Inbred BALB C; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization; D013237:Stereoisomerism; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000083:Acetanilides; D006575:Heterocyclic Compounds, 3-Ring; C000605331:OTX015
keywords: Chiralpak-IA; LC-MS/MS; OTX015; chiral inversion; enantiomers; method validation; mice; mice plasma; pharmacokinetics