Quantitation of 2-hydroxyglutarate in human plasma via LC–MS/MS using a surrogate analyte approach

Aim: 2-Hydroxyglutarate (2-HG) is a target engagement biomarker in patients after treatment with inhibitors of mutated isocitrate dehydrogenase (mIDH). Accurate measurement of 2-HG is critical for monitoring the inhibition effectiveness of the inhibitors. Materials & methods: Human plasma samples were spiked with stable isotope labelled internal standard, processed by protein precipitation, and analyzed using LC–MS/MS. This method was validated following regulatory guidance and has been successfully applied in a clinical study for mIDH inhibition. Results: An LC–MS/MS method with a surrogate analyte approach was developed and validated to measure 2-HG in human plasma with acceptable intra- and inter-assay accuracy and precision. Conclusion: A sensitive and robust LC–MS/MS method was developed and validated for measuring 2-HG in human plasma.