In a world first, a donated human liver has been ‘kept alive’ outside a human being and then successfully transplanted into a patient in need of a new liver. Currently transplantation depends on preserving donor organs by putting them ‘on ice’ – cooling them to slow their metabolism. But this often leads to organs becoming damaged. The Royal Society Enterprise Fund has participated in a £2.75m funding round for OrganOx Ltd which is developing a medical device that will significantly increase the number of human livers available for transplant.
At present there are 30,000 patients on the liver transplant waiting list in Europe and the US, however there are only around 12,000 liver transplants per year in these countries and some 20% of patients die while waiting for a transplant, normally because of a shortage of livers. At the moment the majority of livers for transplant come from heart-beating donors who have been declared brain dead and from whom the liver can be retrieved with minimum deprivation of oxygen, resulting in minimal organ damage.
Donors declared dead following cardiac arrest (non-heart-beating donors) are another potential source of livers. However because of the inevitable period of oxygen deprivation, most of these livers are deemed unsuitable for transplantation using current technology and only about 5% of transplanted livers come from this source.
OrganOx’s device operates by maintaining the organ in a fully functioning state during transport and storage, by providing blood flow, oxygen, nutrients and temperature within physiological parameters required by the liver. This not only enables the liver to be stored safely for a longer period (up to 24 hours) but also provides the surgeon with real-time and cumulative data with which to assess viability and make a decision whether to transplant. This is a major advance over the current method of assessment which is largely subjective.
The liver is particularly susceptible to changes in temperature and so the current method of transport, in a cooled saline solution, has the potential to cause damage and as a result render the liver unviable for transplant. OrganOx’s technology will allow the liver to be transported at body temperature, thereby causing less damage.
The technology, developed at Oxford University and now being trialled at the liver transplant centre at King’s College Hospital as part of a controlled clinical investigation, could preserve a functioning liver outside the body for 24 hours. A donated human liver connected to the device is raised to body temperature and oxygenated red blood cells are circulated through its capillaries. Once on the machine, a liver functions normally just as it would inside a human body, regaining its colour and producing bile.
So far the procedure has been performed on two patients on the liver transplant waiting list and both are making excellent recoveries. The results, carried out at King’s College Hospital in February 2013, suggest that the device could be useful for all patients needing liver transplants.
Sir Peter Williams FRS, Treasurer of the Royal Society, said:
“With almost 2000 livers being retrieved and then discarded each year and a waiting list of 30,000 in the Europe and the US, there’s an obvious need for the technology that OrganOx is working on. The Royal Society Enterprise Fund is very pleased to join OrganOx’s investors and we look forward to the results of their clinical studies later this year. This is exactly the sort of company that the fund was set up to support.”
Dr Les Russell, CEO of OrganOx, commented:
“We are delighted to have received such strong support from both our current and new investors and we offer a warm welcome to our new investors. These funds will allow us to complete our clinical studies and prepare for market launch in 2012 and also to push forward with further exciting developments aimed at increasing the number of organs available for transplant.”