HPB P26 Ex vivo normothermic perfusion of liver, kidney and spleen to predict human pharmacokinetics and assess drug delivery

Abstract

Abstract Background Many emerging therapeutics fail to provide patient benefit due to unpredictable drug delivery and clearance following clinical translation. Normothermic machine perfusion (NMP) can preserve physiological processes in human-sized organs ex vivo, which may facilitate preclinical characterisation of pharmacokinetics and drug delivery. The performance of ex vivo human and porcine clearance organs (liver, kidney and spleen) to 1) predict human drug pharmacokinetics and 2) assess the delivery of emerging therapeutics was investigated. A small molecule chemotherapy (irinotecan) with well-established pharmacokinetics was delivered to determine the former. Nanotherapeutics and viral vectors, two classes of emerging therapeutics, were delivered to determine the latter. Methods Human liver (n=4), kidney (n=4) and porcine liver (n=11), spleen (n=6) and kidney (n=5) underwent NMP. Organ physiology was measured. Irinotecan (Medac) was delivered to human and porcine liver and kidney. Plasma, tissue, bile and urinary irinotecan and its metabolites were quantified by high performance liquid chromatography. Pharmacokinetic parameters were compared to patient data. Non-PEGylated (ThermoFisher) and PEGylated (in-house), nanoparticles were delivered to liver, spleen, and kidney. Nanoparticles were quantified in biological samples by fluorescence. A lentiviral vector (Oxford Biomedica) was administered to liver and viral kinetics and genomic integration determined using RT-qPCR. Noncompartmental analysis was used for pharmacokinetics. Results Prolonged physiological preservation (up to 38 hours) of human liver, kidney and porcine liver, kidney and spleen was achieved with NMP. Human and porcine organs support the pharmacokinetic processes of drug distribution, metabolism and urinary and biliary excretion of irinotecan. Moreover, porcine organs successfully predicted human hepatic clearance, renal clearance and total body clearance with an absolute fold error of 1.14, 1.71 and 1.04 when compared to human literature values. Finally, predictable kinetics and biodistribution of PEGylated and non-PEGylated nanoparticles were demonstrated in NMP clearance organs, and NMP liver supported the integration of lentiviral genome into the host hepatocyte DNA. Conclusions Ex vivo NMP organs can be used to predict human drug clearance and assess therapeutic delivery; an exciting prospect for preclinical drug development and for the delivery of hepatocyte-targeted therapies, with the potential to reduce the time, cost and risk in developing life-saving treatments for patients.