A validated LC-MS/MS method for the quantification of bevacizumab in rat, cynomolgus monkey, and human serum.

Bevacizumab is a humanized monoclonal antibody used in the treatment of advanced colorectal and non-small cell lung cancer. Our main aim was to establish a simple, economical, and high efficiency liquid chromatography tandem mass spectrometry (LC-MS/MS) method for quantifying the content of bevacizumab in various biological fluids (rat, cynomolgus monkey, and human serum). A surrogate peptide of bevacizumab, specifically FTFSLDTSK, was generated through trypsin hydrolysis, and quantified using an isotopically labeled peptide containing two amino acids, FTFSLDTSK[13C6, 15N2]ST, as an internal standard to correct for variations introduced during the enzymatic hydrolysis process and any mass spectrometry variabilities. The pre-treatment process included denaturation, disulfide bond reduction and alkylation, trypsin hydrolysis, and termination of the reaction, with a total duration of approximately 2.5-3 h. The results of the methodological validation showed that the linear range in three different biological matrices was 0.2 µg/mL to300 µg/mL, with an LLOQ of 0.2 µg/mL. The precision and accuracy of the measurements met the required standards. The validated LC-MS/MS method was used to conduct pharmacokinetic analysis in rats administered bevacizumab at a dose of 10 mg/kg intravenously.

Characterization of in-vivo human metabolites of the oral nucleoside anti-COVID-19 drug VV116 using UHPLC-Orbitrap-MS.

VV116 is an oral nucleoside anti-COVID-19 drug undergoing clinical trials in China. We aimed to characterize its metabolites in plasma, urine, and feces of healthy Chinese male subjects after a single oral administration of 400 mg VV116, by using UHPLC-UV-Orbitrap-MS. After oral administration, VV116 was almost completely converted into the metabolite 116-N1. Seventeen other metabolites produced by the subsequent metabolism of 116-N1 were also detected, including 6 phase I metabolites and 11 phase II metabolites resulting from hydrolysis, oxidative deamination, oxidation, and CN-group removal and conjugations. The results were exploratory. The major metabolite of VV116 in human plasma and urine was 116-N1, the main metabolites in feces were M2 and 116-N1. We then synthesized a reference M2 standard and confirmed its structure by MS and NMR.

Synthesis and antidepressant effect of novel aralkyl piperazine and piperidine derivatives targeting SSRI/5-HT1A/5-HT7.

A series of novel aralkyl piperazine and piperidine derivatives were synthesized, and evaluated for their serotonin reuptake inhibitory and 5-HT1A/5-HT7 receptors affinities activity. Antidepressant activities in vivo of the selective compound were screened using the forced swimming test (FST) and tail suspension test (TST). The results indicated that compound 19a exhibited high affinities for the 5-HT1A/5-HT7 receptors (5-HT1A, Ki = 12 nM; 5-HT7, Ki = 3.2 nM) coupled with potent serotonin reuptake inhibition (IC50 = 14 nM) and showed a marked antidepressant-like effect in the FST and TST models.

Synthesis and antidepressant-like activity of novel aralkyl piperazine derivatives targeting SSRI/5-HT1A/5-HT7.

A series of novel aralkyl piperazine derivatives were synthesized, and evaluated for their serotonin reuptake inhibitory and 5-HT1A/5-HT7 receptors affinities activity. Antidepressant activities in vivo of the compounds were screened using the forced swimming test (FST) and tail suspension test (TST). The results indicated that compounds 21k (RUI, IC50 = 31 nM; 5-HT1A, 5-HT7, ki = 62, 12 nM) and 21n (RUI, IC50 = 25 nM; 5-HT1A, 5-HT7, ki = 28, 3.3 nM) exhibited high affinities for the 5-HT1A/5-HT7 receptors coupled with potent serotonin reuptake inhibition. Specifically, the most promising compound 21n possessed a good oral pharmacokinetic properties and an acceptable hERG profile, and showed potent antidepressant-like effect in the FST and TST models.

Qualitative and quantitative studies on impurities in G004, a potential hypoglycaemic agent, using liquid chromatography, nuclear magnetic resonance and mass spectrometry.

G004, 1-(4-(2-(4-bromobenzenesulphonamino) ethyl) phenylsuphonyl)-3-(trans-4-methylcyclohexyl) urea, is being developed as a potential hypoglycaemic agent. In this study, the related compounds in the bulk drug substance of G004 were analyzed both qualitatively and quantitatively. An unknown compound in the drug, which has never been reported, was isolated using preparative liquid chromatography and characterized as 1-(4-(2-(2-bromobenzenesulphonamino) ethyl) phenylsuphonyl)-3-(trans-4-methylcyclohexyl) urea using nuclear magnetic resonance and mass spectrometry. Moreover, a reversed-phase liquid chromatography method was developed for quantification of both the major impurities and the main constituent. The proposed method was validated and applied during impurity studies and quality control analysis of the bulk drug and laboratory-prepared samples of G004.