Monday, May 3, 2010

Extending the Life of Donated Organs

An experimental solution could buy time for transplant patients.


1-The 100,000-plus U.S. patients waiting for organ transplants face a perilous race against time. Most organs can only be preserved outside the body for somewhere between four and 24 hours--a problem that aggravates the chronic shortage of donors. In 2008, 6,684 patients died waiting for organs, according to the National Kidney Foundation.



2-A Harvard scientist is hoping to change those bleak statistics. Hemant Thatte, associate professor of cardiothoracic surgery, has developed a liquid solution that may preserve organs for up to 10 days outside the body

3-Thatte's lab devised a recipe of 21 chemical compounds that they believe will slow down the process of cell deterioration. "Our whole goal is to maintain the metabolism of the organ without having to lower the temperature" of the preservation system, Thatte explains. "It's like a state of suspended animation." Thatte dubbed the solution "Somah," which is Sanskrit for "ambrosia of rejuvenation."

4-In October 2009, Thatte and his colleagues published a paper in the journal Circulation comparing Somah to the widely used preservation solution Celsior, made by biotech company Genzyme. 

5-The researchers harvested hearts from female pigs, stored them in one of the two solutions, then biopsied them at several points over the next four hours. They observed the function of the cardiomyocyte and endothelial cells--both of which must be preserved in order for the transplanted heart to survive over the long term. 

6-By measuring key proteins, they determined that the rate of cell death was significantly slower in the Somah-preserved hearts than it was in those stored with Celsior. Their experiments in pigs suggest that Somah keeps hearts and livers viable for at least 10 days. By contrast, solutions such as Celsior can only be counted on to preserve hearts and livers for about four and 12 hours, respectively.

7-Three students who were taking a class at Harvard's business school got wind of Thatte's research from Harvard's Office of Technology Development, and they decided to write up a business plan as an assignment. The team named their startup Hibergenica and set out to find investors in January. 

8-They believe they need $5 million to get Somah to market.The Hibergenica team is pitching investors on the idea that Somah will expand the market for transplanted organs from $30 million a year to as much as $200 million. Some of that growth will arise from an increased supply of viable organs, which could potentially be shipped from faraway places like Hawaii, or even from overseas. Team member Haytham Elhawary, a scientist at Brigham & Women's hospital who was auditing the business-plan class, believes market expansion might also come from premium pricing--Somah could fetch a price that's as much as five times higher than competing solutions, he says.

9-To command that price tag, Hibergenica will have to show that Somah improves the quality of harvested organs, and thus boosts the long-term survival prospects for transplant patients. The solution has the potential to achieve that goal, the entrepreneurs believe, because it is designed to preserve the metabolism of the organs while they are outside the body.
The ingredients work together to transform tissue metabolites into products that protect cells. 

10-In the heart, for example, Somah converts ammonia--a toxic byproduct of tissue metabolism--into a metabolite that augments the nitric-oxide pathway. "That opens up the vasculature of the heart, which helps to preserve its function," says Alison Williams, a scientist at Harvard's School of Public Health, who is serving as Hibergenica's chief scientific officer. Specifically, nitric oxide inhibits vasoconstriction, clotting, and inflammation.

11-Hibergenica's plan is to build on Thatte's initial research by transplanting Somah-preserved organs from pigs into other pigs, so they can measure post-transplant survival rates. If their expectations are met, they'll need about a year of human trials before they can apply for FDA approval. They'll start with kidneys and other abdominal organs, "because that's where the volume is," Elhawary says. If all goes well, they'll test the solution in heart and lung transplants.

12-There haven't been any significant advances in organ preservation in over 20 years, though other companies are certainly trying. In March, Andover, MA-based TransMedics raised $36 million to develop a technology that uses blood perfusion to preserve organs ina system designed to mimic the conditions of the human body.
Proving that Somah reduces organ damage will be critical for convincing transplant surgeons to embrace the solution, says Luca Cicalese, director of the Texas Transplant Center and John Sealy Distinguished Chair in Transplantation Surgery at the University of Texas Medical Branch in Galveston, TX. "Organs get wasted not because of time factors, but because of quality issues," Cicalese says. "If this solution reduces damage to cells, that would be a major help."

13-Other surgeons argue that extending the time window for transplantation could, in fact, offer significant advantages. Michael Marvin, chief of transplant surgery at the University of Louisville, points out that many donated organs have to be flown on chartered airplanes and transplanted in the middle of the night. "Surgeons are working on very little sleep, which may not be optimal," he says. And if organs could be flown on commercial airlines instead of chartered jets, "I imagine there would be a dramatic reduction in costs," he adds.

From:- MIT-Technology Review



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