The goal of this study is to find out if quality assessment by normothermic machine perfusion can be used to safely increase the number of usable donor livers, helping more people get transplants faster and with better results. This process keeps a donated liver working outside the body before transplantation, allowing surgeons to assess whether livers previously considered unsuitable can still be used.

The main questions this study aims to answer are:

• Does this method help patients get a transplant sooner?
• Can this method make more livers available for transplant?
• Does it improve survival and health after transplant?

Participants in this study must be on the waiting list for a liver transplant with a ReMELD-Na-Score of 21 or less (equivalent to MELD ≤25) and must not qualify for certain special exceptions. Participants will be randomly placed into one of two groups:

• Experimental group: In addition to regular organ offers, these participants may receive a liver that was initially not considered for transplantation but meets quality standards after at least four hours of machine perfusion.
• Control group: These participants will receive a liver through the usual transplant process.

The main measure of success is how quickly participants receive a transplant. Researchers will also look at other important factors, such as survival rates, quality of life, hospital stay, and complications after transplant.

This study may help improve liver transplantation by making better use of available donor livers, reducing waiting times, and improving patient outcomes.

Liver transplantation is the treatment of choice for patients with advanced liver cirrhosis, hepatocellular carcinoma within the Milan criteria, and severe metabolic or autoimmune liver diseases. However, organ shortage remains a significant issue, particularly in Germany, where only 58% of patients on the waiting list received a transplant in 2022. Patients with MELD ≤25, who are ineligible for [Non]-Standard Exception criteria, face particularly long waiting times and lower transplant rates.

Despite the shortage, approximately 24% of all liver grafts in Germany are declined due to donor age, macrosteatosis, or prolonged cold ischemia. Emerging technologies, such as NMP, allow for objective graft quality assessment before transplantation. Several non-randomized studies in the UK, Netherlands, Australia, and the USA have demonstrated the potential of NMP to increase organ utilization. The ExTra trial is the first randomized controlled study to investigate whether declined liver grafts, following NMP-based quality assessment, can safely and effectively reduce the waiting time for patients with ReMELD-Na-Score ≤ 21(equivalent to MELD ≤25).

Inclusion Criteria:

• Able to consent
• ≥ 18 years old
• Listed in status "transplantable" by the transplant conference of the study centre for liver transplantation, according to the guidelines of the German Medical Association valid at the time of inclusion
• ReMELD-Na-Score ≤ 21 (equivalent to MELD ≤25), not eligible for [non]standard exceptions
• Medically suitable and informed for transplantation with an organ that fulfils extended donor criteria (Eurotransplant ECD criteria)
• Patient information and written consent to participate in the Extra trial
• No participation in another interventional study during participation

Exclusion Criteria:

• Listed for retransplantation
• High-Urgency Listing
• Listed for combined organ transplantation
• Pregnancy

Individual Participant Data will not be shared due to data protection regulations and ethical considerations. Given the sensitive nature of the data, strict confidentiality measures must be maintained to protect participants' privacy. Compliance with GDPR and institutional policies prevents the disclosure of personally identifiable information, ensuring that data handling aligns with legal and ethical standards.