Venetoclax has emerged as a breakthrough for treatment of leukemia with a wide interindividual variability in pharmacokinetics. Herein, a rapid, sensitive, and reliable UPLC-MS/MS method for quantification of venetoclax in plasma was developed and validated. The method was operated in the multiple-reaction monitoring (MRM) mode to detect venetoclax at m/z transition 868.5 > 321.0 and IS at 875.5 > 321.0, respectively. Protein precipitation prior to injection into the LC-MS/MS and the analyte was separated on an ACQUITY UPLC BEH C18 column by gradient elution with acetonitrile and 0.1% formic acid in water. Linear calibration curves were obtained in the range of 25–8000 ng/mL. The specificity, recovery, matrix effect, and stability also met the acceptance criteria of FDA guidance. The method was successfully applied to analyze plasma in acute myeloid leukemia (AML) patients. The peak plasma concentration (C_max) of venetoclax in Chinese AML patient was 2966.0 ± 1595.0 ng/mL while the trough concentration (C_min) was 1018.0 ± 729.4 ng/mL. Additionally, C_max and C_min showed a positive correlation with AST levels. Furthermore, C_max was significantly higher in the older patients. The present method can be applied for TDM of venetoclax in treatment of hematological cancers.

Alpinetin, a bioactive flavonoid, has been known to have a diverse therapeutic effect, with namely anti-inflammatory, anticancer and antioxidant effects with low systemic toxicity. This study aimed to obtain metabolic profiles of alpinetin in orally administrated rats. The metabolites of alpinetin were systematically analyzed and identified by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS). The chromatographic separation was achieved on a High Strength Silica (HSS) T3 (1.8 μm, 2.1 × 100 mm) column with the mobile phase consisting of water containing 0.1% formic acid and acetonitrile with 0.1% formic acid via gradient elution. An extracted ion chromatogram strategy based on multiple prototype/metabolite intermediate templates and 71 typical metabolic reactions was proposed to comprehensively profile the metabolites of alpinetin. With the metabolite profiling strategy, altogether 15 compounds were recognized from urine, plasma, bile and feces of rats after intragastric administration of alpinetin for the first time. The prototype, glucuronide conjugates and phenolic acids metabolites were the probable predominant form of alpinetin in rats. This work showed a comprehensive study of the probable metabolic pathways of alpinetin in vivo, which could provide meaningful information for future pharmacological studies.

The clinical pharmacodynamics of tacrolimus in renal transplant patients has significant interindividual variability. T lymphocytes were selected to study the pharmacodynamic response of tacrolimus, which was significantly correlated with renal function and the outcome of renal transplant patients. Ultra-performance liquid chromatography–quadrupole time-of-flight mass spectroscopy (UPLC/Q-TOF-MS) was performed to obtain the metabolic profiles of 109 renal transplant patients. A partial least squares (PLS) model was constructed to screen potential biomarkers that could predict the efficacy of tacrolimus. Multinomial logistic regression analysis established a bridge that could quantify the relationship between the efficacy of tacrolimus and biomarkers. The results showed a good correlation between endogenous molecules and the efficacy of tacrolimus. Metabolites such as serum creatinine, mesobilirubinogen, L-isoleucine, 5-methoxyindoleacetate, eicosapentaenoic acid, N₂-succinoylarginine, tryptophyl-arginine, and butyric acid were indicated as candidate biomarkers. In addition, the key biomarkers could correctly predict the efficacy of tacrolimus with an accuracy of 82.5%. Finally, we explored the mechanism of individual variation by pathway analysis, which showed that amino acid metabolism was significantly related to the efficacy of tacrolimus. Moreover, orthogonal partial least squares discriminant analysis (OPLS-DA) showed that there was no difference in key metabolites among different pharmacodynamic groups at 1 month and 3 months after dose adjustment, suggesting that pharmacometabonomics is a useful tool to predict individual differences in pharmacodynamics and thus to facilitate individualized drug therapy.