With the need outweighing the supply for organ transplants, the Toronto General Hospital has embarked on a mission to use donor lungs that have been previously infected with hepatitis C. So far, they have successfully transplanted hepatitis C infected lungs into 10 patients at the hospital.
All of the patients have recovered, with eight of them testing negative to the infection and the other two currently taking the drug regimen.
The transplants are part of a clinical trial that is the first to assess the safety of transplanting hepatitis positive organs to non-infected patients using the ex vivo technology. Developed at TG in 2008, the Toronto Ex Vivo Lung Perfusion System (EVLP) perfuses organs outside of the body, allowing doctors to assess the organ and predict how well it will do before transplantation.
“With the opioids crisis and persistent high rates of intravenous drug use, we have a great number of potential lung donors who are hepatitis C positive – many of whom didn’t even know they were sick when they were alive,” says Dr. Marcelo Cypel, thoracic surgeon at TG, UHN, scientist at Toronto General Hospital Research Institute (TGRI) and principal investigator in the study. “The current protocol is to not use these organs, but we started to question if that still made sense in an era when direct anti-viral agents (DAAs) can cure hepatitis C.”
The first phase of the study was comprised of the 10 surgeries – performed between October, 2017 and May, 2018. The average age of the organ donors was 33 and the average age of the recipients was 64.
For this study, lungs were placed in the EVLP circuit in a sterile dome for six hours. The surgical team was able to evaluate the lung function and be certain that the organs were suitable for transplant, despite being infected with hepatitis C.
After six hours, EVLP reduced the hepatitis C virus count to very low levels. As expected, patients still contracted the disease. However, they tested negative for hepatitis within only three weeks of treatment with DAAs, in average.
“This is an initial study, but it shows positive results,” says Dr. Feld. “It suggests that it is safe to use these organs which otherwise we could not have used. This could eventually be a big boost for organ donation.”
Dr. Cypel estimates that accepting hepatitis C positive donors would increase the number of lungs available for transplant by 1,000 per year in North America. Currently, approximately 2,600 lung transplants are done per year in Canada and the United States combined.
As of 2016, there were more than 240 patients waiting for a lung transplant in Canada alone and the estimate is that 20 per cent of patients die while waiting for lungs to become available.
This study will be followed by a second phase that will further assess techniques to use organs carrying the virus. This innovative method will open more doors for patients and is an exceptional example of the latest developments that are happening rapidly in the field of life sciences.