Department of Pharmacology and Therapeutics, University of Liverpool, Liverpool L7 3NY, UK; Centre of Excellence in Long-acting Therapeutics (CELT), University of Liverpool, Liverpool L7 3NY, UK.
Department of Chemistry, University of Liverpool, Liverpool L69 3BX, UK; Centre of Excellence in Long-acting Therapeutics (CELT), University of Liverpool, Liverpool L7 3NY, UK.
J Chromatogr B Analyt Technol Biomed Life Sci. 2023 Aug 1;1228:123823. doi: 10.1016/j.jchromb.2023.123823. Epub 2023 Jul 16.
Currently nitazoxanide is being assessed as a candidate therapeutic for SARS-CoV-2. Nitazoxanide is rapidly broken down to its active metabolite tizoxanide upon administration. Unlike many other candidates being investigated, tizoxanide plasma concentrations achieve antiviral levels after administration of the approved dose, although higher doses are expected to be needed to maintain these concentrations across the dosing interval in the majority of patients. Here an LC-MS/MS assay is described that has been validated in accordance with Food and Drug Administration (FDA) guidelines. Fundamental parameters have been evaluated, and these included accuracy, precision and sensitivity. The assay was validated for human plasma, mouse plasma and Dulbecco's Modified Eagles Medium (DMEM) containing varying concentrations of Foetal Bovine Serum (FBS). Matrix effects are a well-documented source of concern for chromatographic analysis, with the potential to impact various stages of the analytical process, including suppression or enhancement of ionisation. Herein a validated LC-MS/MS analytical method is presented capable of quantifying tizoxanide in multiple matrices with minimal impact of matrix effects. The validated assay presented here was linear from 15.6 ng/mL to 1000 ng/mL. The presented assay here has applications in both pre-clinical and clinical research and may be used to facilitate further investigations into the application of nitazoxanide against SARS-CoV-2.
目前硝唑尼特正在被评估为治疗 SARS-CoV-2 的候选药物。硝唑尼特在给药后迅速分解为其活性代谢物替硝唑。与许多正在研究的其他候选药物不同，替硝唑的血浆浓度在给予批准剂量后达到抗病毒水平，尽管大多数患者需要更高的剂量来维持整个给药间隔的这些浓度。这里描述了一种已根据美国食品和药物管理局 (FDA) 指南验证的 LC-MS/MS 测定法。已评估了基本参数，包括准确性、精密度和灵敏度。该测定法已针对人血浆、鼠血浆和含不同胎牛血清 (FBS) 浓度的 Dulbecco's Modified Eagles Medium (DMEM) 进行了验证。基质效应是色谱分析中一个有据可查的关注点，有可能影响分析过程的各个阶段，包括抑制或增强离子化。本文介绍了一种经过验证的 LC-MS/MS 分析方法，该方法能够在最小基质效应的情况下定量多种基质中的替硝唑。本文中呈现的经验证的测定法在 15.6 ng/mL 至 1000 ng/mL 的范围内呈线性。这里呈现的测定法在临床前和临床研究中都有应用，并且可以用于促进对硝唑尼特在治疗 SARS-CoV-2 中的应用的进一步研究。
