ADME absorption, distribution, metabolism, and excretion AMS accelerator mass spectrometry AUC area under the curve CKD chronic kidney disease DPM disintegrations per minute DRM drug-related material EPO erythropoietin HIF hypoxia-inducible factor HPLC high-performance liquid chromatography HPLC–MSn HPLC-tandem mass spectrometry LC-MSn liquid chromatography–tandem mass spectrometry LLQ lower limit of quantification LSC liquid scintillation counting PHI prolyl hydroxylase inhibitor TP1...