Writing in the December issue of the American Journal of Transplantation, a research team headed by Dr. Massimo Trucco (right) of Children's reported that genetically engineered pancreas cells from pigs were still producing insulin and preventing diabetes in a monkey more than a year after transplant.

If further monkey trials show similar success,  scientists may be ready to conduct human trials with pig cells in two to three years, said Dr. David Ayares, CEO and chief scientific officer of Revivicor Inc., (left) the Blacksburg, Va., company that grows the special pigs.

One solution to type 1 diabetes is pancreas transplants, but as with other organs, there is a severe shortage of donated pancreases in the United States. Last year, more than 3,700 people were waiting for pancreas transplants, but only about 435 were performed, according to the United Network for Organ Sharing.

Even fewer pancreases are available for so-called islet cell transplants, recently announced for Scotland, in which the cells that produce insulin are extracted and infused into patients' livers, where they establish "mini-pancreases" to produce insulin. For many diabetes patients who get human islet cell transplants today, the cells only last from several months to a few years, and the patients then either have to get more transplanted cells or go back to injected insulin, Ayares said.

That's where pig cells may be a solution, he said, and it's why the results of the new study are so exciting. Not only are pigs similar to humans biologically, he said, but they can be grown to adulthood in about six months and don't face the same ethical and medical restrictions for transplant use as monkeys and other primates do.

In the new study, Revivicor grew pigs that were genetically engineered to include a human gene that makes a protein called CD46, which helps suppress the body's immune attack on transplanted cells.

Back in November 2004 Revivicor was granted rights to use Geron Corp's nuclear transfer technology for animal cloning. The first license grants Revivicor the right to use the technology to produce animal organs and tissues for xenotransplantation which involves the use of animal organs and tissues for transplant into humans, offers the potential to address critical shortages of donated human tissues and fulfill currently unmet clinical needs.

The second license grants Revivicor the right to use the technology to produce human proteins from the blood of animals for pharmaceutical uses, such as polyclonal antibodies for vaccine use. In consideration for the licenses, Geron received an equity interest in Revivicor. Geron will also receive a royalty on Revivicor's future revenues.

In 2005 Revivicor Inc purchased essentially all of the IP and tangible assets of XenoTrans Ltd. (XTL), an Australian company also focused on xenotransplantation technology. Revivicor acquired, among other assets, all XTL IP)and know-how relating to pig alpha-1,3 galactosyl transferase (“GT”).  Elimination or knockout of the pig GT gene is a critical step for prevention of hyperacute rejection of pig tissues when transplanted into humans. 

Revivicor was the first company to clone pigs, and later, was the first  company to generate GT negative pigs (“knockout” pigs).  XTL, a spinout company from the Austin Research Institute (ARI), was the exclusive licensee of GT and other xenotransplantation IP from ARI.  ARI has the first issued patents in the United States and Australia for the pig GT gene and its use for the development of GT knockout pigs. 

Revivicor, through this asset acquisition, obtained exclusive rights to the ARI GT IP.  As part of the transaction, XTL shareholders received a minority equity stake in Revivicor.  Dr. Ian Mckenzie, one of the key inventors on the ARI GT patent and the former CEO of XTL joined Revivicor’s Scientific Advisory Board.

Revivicor has been collaborating for the past three years with the University of Pittsburgh Medical Center (claimed the Number 1 transplant hospital in the world) on pre-clinical testing of organs from GT knockout pigs in non-human primates. 

In addition, the Company has an ongoing collaboration with scientists at Children's Hospital (Pittsburgh), as part of an effort funded by the Juvenile Diabetes Research Foundation (JDRF), for the development of pig islet xenografts intended to cure diabetes.