Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 2 de 2
J Pharm Biomed Anal ; 212: 114646, 2022 Apr 01.
Article in English | MEDLINE | ID: covidwho-1699455


SBECD (Captisol®) with an average degree of substitution of 6.5 sulfobutylether functional groups (SBE = 6.5), is a solubility enhancer for remdesivir (RDV) and a major component in Veklury, which was approved by FDA for the treatment of patients with COVID-19 over 12 years old and weighing over 40 kg who require hospitalization. SBECD is cleared mainly by renal filtration, thus, potential accumulation of SBECD in the human body is a concern for patients dosed with Veklury with compromised renal function. An LC-MS/MS method was developed and validated for specific, accurate, and precise determination of SBECD concentrations in human plasma. In this method, the hexa-substituted species, SBE6, was selected for SBECD quantification, and the mass transition from its dicharged molecular ion [(M-2H)/2]2-, Molecular (parent) Ion (Q1)/Molecular (parent) Ion (Q3) of m/z 974.7/974.7, was selected for quantitative analysis of SBECD. Captisol-G (SBE-γ-CD, SBE = 3) was chosen as the internal standard. With 25 µL of formic-acid-treated sample and with a calibration range of 10.0-1000 µg/mL, the method was validated with respect to pre-established criteria based on regulatory guidelines and was applied to determine SBECD levels in plasma samples collected from pediatric patients during RDV clinical studies.

COVID-19 , beta-Cyclodextrins , Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , COVID-19/drug therapy , Child , Chromatography, Liquid , Humans , SARS-CoV-2 , Sodium , Tandem Mass Spectrometry/methods
Anal Biochem ; 617: 114118, 2021 03 15.
Article in English | MEDLINE | ID: covidwho-1064675


Remdesivir (RDV) is a phosphoramidate prodrug designed to have activity against a broad spectrum of viruses. Following IV administration, RDV is rapidly distributed into cells and tissues and simultaneously metabolized into GS-441524 and GS-704277 in plasma. LC-MS/MS methods were validated for determination of the 3 analytes in human plasma that involved two key aspects to guarantee their precision, accuracy and robustness. First, instability issues of the analytes were overcome by diluted formic acid (FA) treatment of the plasma samples. Secondly, a separate injection for each analyte was performed with different ESI modes and organic gradients to achieve sensitivity and minimize carryover. Chromatographic separation was achieved on an Acquity UPLC HSS T3 column (2.1 × 50 mm, 1.8 µm) with a run time of 3.4 min. The calibration ranges were 4-4000, 2-2000, and 2-2000 ng/mL, respectively for RDV, GS-441524 and GS-704277. The intraday and interday precision (%CV) across validation runs at 3 QC levels for all 3 analytes was less than 6.6%, and the accuracy was within ±11.5%. The long-term storage stability in FA-treated plasma was established to be 392, 392 and 257 days at -70 °C, respectively for RDV, GS-441524 and GS-704277. The validated method was successfully applied in COVID-19 related clinical studies.

Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/blood , Drug Monitoring/methods , Furans/blood , Pyrroles/blood , Tandem Mass Spectrometry/methods , Triazines/blood , Adenosine/analogs & derivatives , Adenosine Monophosphate/blood , Alanine/blood , COVID-19/drug therapy , Chromatography, High Pressure Liquid/methods , Humans , Limit of Detection