What are we investigating?
This trial is a multi-national study looking at a new method of storing and preserving a liver intended for transplantation. The current standard method of liver preservation is using an ice box. This cools the liver down to about 4 degrees C, slowing down all the cellular functions and so meaning the liver can be preserved for as many as 12 hours.
However, this form of preservation has its limitations. When the liver is cooled down, many of the cells are still functioning, but very slowly. This means they are still using up their energy and oxygen reserves and so are slowly deteriorating. When the cells run out of oxygen, they then start functioning without oxygen, leading to a build-up of toxic substances which also cause damage to the cells. Because of this, livers which are stored on ice have to be of very good quality to start with, so that they can withstand the trauma of going without blood, oxygen or nutrients for several hours and then still function in the transplant recipient.
Why are we testing new ways of organ preservation?
Over the past 10 years the number of organ donors in the UK has increased by about 50%. There has been a similar increase in many other countries. However, the number of livers suitable for transplantation has not increased in the same way. This is because the majority of additional donors have either had many other medical conditions or been quite elderly, meaning their livers could not be used. Liver transplant surgery, however, has become more and more successful, and so is being used to treat a wider range of conditions that cause end-stage liver failure. Currently, in the UK, more people are added to the liver transplant waiting list every year than actually receive a transplant. This results in the fact that you are currently more likely to die while waiting for a liver transplant than in the first year after a transplant operation.
What are our aims?
This study is investigating a new technology which it is hoped will improve the preservation of livers intended for transplantation. Once the liver has been removed from the donor, it is attached to the machine which perfuses it with oxygenated blood, nutrients and some medications at normal body temperature (normothermic machine perfusion = NMP). The liver then remains on the machine throughout its transport and storage until it is ready to be transplanted into the recipient. Previous animal studies have suggested that this method of preservation can improve the quality of organs and even reverse some of the damage that has occurred to the organ during the retrieval process. A safety study has been performed in 20 patients, all of whom have made a good recovery and left hospital, although the full results are currently being analysed.
Where is the study carried out?
The COPE liver trial is carried out in four European countries (England, Belgium, Germany, Spain) involving a total of seven different transplant centres. It went live in England in June 2014 and in Belgium in December 2014 with Spain following in January 2015 and Germany to follow later on in the year. The trial will randomise a total of 260 livers to either conventional storage on ice, or preserved using NMP. We will be measuring a wide range of outcomes looking at liver injury, survival, whether the machine can predict which organs will perform best and also the quality of life of the organ recipients after the operation.
Where can I get more information?
For more information on this trial please email Dr David Nasralla through David.Nasralla@nds.ox.ac.uk.
Liver trial: information for patients