Assessing the Safety and Efficacy of a Portable Ex Vivo Oxygenated, Normothermic Liver Perfusion System (OrganOx Metra™ ) Prior to Liver Transplantation

The standard approach for storage and transportation of livers for transplantation involves cold perfusion with Histidine-tryptophan-ketoglutarate (HTK) or alternative solutions, and storage in sterile bags surrounded by preservation solution in a box by ice. The prolonged cold ischemic injury substantially compounds pre-existing donor liver graft injury, further exacerbating potential risk for recipients. Normothermic perfusion may eliminate cold ischemic injury, and provide a unique opportunity to further assess ex vivo function of the most marginal organs before they are transplanted. Being able to select or eliminate organs in this manner would provide additional livers for transplantation while at the same time minimizing risk for recipients.

This non-randomized, open-label, single arm, prospective trial is to assess safety and preliminary efficacy of normothermic machine perfusion on livers accepted under standard and expanded criteria for standard liver transplantation (n=50). Following assessment of donor and recipient eligibility and confirmation of consent, the liver will be preserved on OrganOx metra™ either at the donor hospital or where more practical transported to the University of Alberta hospital with ≤ 6 hours of cold storage and then placed on the metra™ for ≥ 4 hours ('back to base' sub-analysis). At the end of preservation, the liver will be transplanted and the patient managed according to standard local practice and protocols. 100 anonymized patient data from the University of Alberta Hospital Liver Transplant database will be utilized for the matched controls. Enrolled subjects will participate in the study for 30 days (the accrued period to capture primary and secondary end-points: graft and patient survival, graft function, NMP perfusion parameters). Additional routine (non-research) biochemical and survival data will be collected and documented at 3, 6, 9 and 12 months post-transplant. Primary outcomes will be analyzed and reported 30 days following transplantation of the last subject in the study.