Can a device packed with human liver cells temporality take over liver function to give patients with damaged livers the time needed for the liver to regenerate – or keep the patient stable enough so that they can undergo a liver transplant? These are the questions confronting doctors testing the latest generation of the “extracorporeal liver assist device,” known as ELAD. “It doesn’t replace a liver,” cautions Dr. Todd Frederick of California Pacific Medical Center. But, “if we could buy some time while the liver is recovering, that potentially would be a great advance,” notes Dr. Lena Napolitano of the University of Michigan, who like Dr. Frederick is currently helping test the ELAD.
Elizabeth Blaj from San Diego already knows the answer – at least for her. “I believe that machine kept me alive for five days,” she says. Last October, her doctors expected that she would die while waiting for a liver to arrive at Scripps Clinic. With her liver so damaged, the only option for Blaj was a transplant. Unfortunately, however, a dying liver can cause a chain reaction. Kidneys shut down, bleeding begins and the patient slips into a coma. Even when a liver is available, some patients are simply too sick to undergo such a difficult procedure.
Scientists have spent the last decade trying to develop an artificial liver. Early devices focused solely on filtering poisons in the blood. But the liver fulfills other important functions, such as generating chemicals needed for blood clotting and metabolism. The hope is that by adding living liver cells gathered from pigs or humans to filtering machines, scientists will be able to more effectively mimic the function of the organ. The ELAD, which utilizes human cells, “comes closer to replacing the amount of liver” people need, says Dr. Robert Brown of New York-Presbyterian Hospital and Columbia University.
The FDA is asking scientists to study how three to ten days of support provided by ELAD compares to patients receiving standard supportive care. Manufacturer Vital Therapies Inc. says that in a study it conducted in China, 85 percent of patients who received ELAD therapy survived short-term, compared with only 50 percent of those patients who received regular care. In the U.S., the study just began in October. No conclusions can yet be drawn, but as Dr. Napolitano stresses, “kidney dialysis got off to a similar rocky start in tests of the dying before doctors could determine how it best worked and use it on the less sick.” This is the ultimate goal for whatever artificial liver scientists eventually develop.
News Release: Doctors test latest attempt at artificial liver www.news.yahoo.com February 2, 2009
