Allen-Hoffmann: StrataGraft holds promise for burn victims
By Brian E. Clark
When Lynn Allen-Hoffmann watched a major burn surgery at the UW-Madison hospital more than a decade ago, she was hooked.
“That was my epiphany,” said Allen-Hoffmann, a Ph.D who is the CEO and chief scientific officer at Stratatech, a Madison-based company that is developing living skin substitute products.
Her company recently embarked on second multi-center clinical trial of the company’s StrataGraft living skin substitute. The trial will assess the safety and clinical use of the skin substitute in the long-term treatment of patients with severe second-degree burns.
WisBusiness audioAllen-Hoffmann said witnessing the grafting procedure on a farmer who had third-degree burns on 95 percent of his body got her “completely focused and passionate about taking the discovery that had been made in my lab and applying it to help people who really need novel products ... to help them heal.
“It was very moving for me,” she said. “I remain as passionate about it now as the day I stepped out of his surgery.”
Allen-Hoffmann’s discovery was a long-lived skin cell line derived from an infant’s foreskin, discarded after a circumcision. In an experiment, she found that these cells -- keratinocytes -- also grew into new, three-dimensional healthy skin.
She named the cells NIKS® , short for "near-diploid immortalized keratinocytes that form skin."
Allen-Hoffmann, whose company is located in Madison’s Resarch Park, modestly calls the find “serendipitous.” WARF, the Wisconsin Alumni Research Foundation, holds the patent to her discovery.
The privately held firm boot-strapped it at first, with Allen-Hoffmann literally culturing cells in a storeroom that had a sink at the MGE Innovation Center.
“We didn’t have a true, bona fide lab there, but I could get a four-foot hood in the room,” she recalled.
She said there was nothing -- at first -- that she could discern that was special about the infant’s tissue.
“What I believe occurred is that while those cells were growing in my lab at the UW, they developed the characteristic to have an expanded life span in culture,” noted Allen-Hoffmann, who said she has been unable to recreate cells with similarly altered characteristics.
“I did nothing,” she said. “I always emphasize that my contribution was very humble.”
Because Stratatech has master cell banks produced from those first cells, she said the company has a sufficient number of them to have “commercially viable entity for quite a while.”
But first, she explained, the company will have to successfully complete its second clinical trial. The study is being funded, in part, by the Department of Defense because so many soldiers were badly burned by roadside bombs in the wars in Iraq and Afghanistan.
A first trial, which ended recently, showed that the product could be used safely to treat patients who had suffered serious burns, or lost skin because of accidents or ailments such as necrotizing fasciitis, commonly known as the flesh-eating disease.
The trial also proved, she said, that StrataGraft was as effective as the current standard of care, which uses cadaver skin for healing the wound bed. Cadaver skin can be hard to obtain and may carry infectious bacteria.
But she said StrataGraft has neither of those drawbacks.
The other thing Allen-Hoffmann said researchers learned was that her product helped the wound establish a vascular supply of blood and “pink up.” Moreover, there was no rejection of the new tissue.
The results of the trial have been submitted to the FDA. In addition, the clinical outcomes and the immunological reactions of patients to StrataGraft have been published, she said.
Now, in the second trial, clinicians are hoping to learn if StrataGraft can remain on the wound and serve as a type of universal replacement for people who have lost skin.
That could mean that patients might no longer need to go through a second surgery in which skin from their own bodies is removed in a procedure called an “autograft” and then transplanted to the original wound.
Allen-Hoffmann said patients sometimes suffer donor-site wounds, which could eliminated by using StrataGraft tissue.
“We are hopeful that the presence of our tissue will enable the patient’s own tissue to heal underneath over time without taking that autograft. So we are going to be reducing surgical procedures and eliminating a lot of pain and hopefully promoting wound healing.”
Allen-Hoffmann said the first patient has been enrolled in the trial in North Carolina and her company will be working with four other hospitals, including UW-Madison.
“In this trial, we’ll be very aware if StrataGraft can improve scarring,” she said. “This is a real challenge with these patients.”
She said the trial will work with veterans at the BrookeArmy Hospital at Fort Sam Houston in San Antonio, Texas. In the eight years of war in Iraq alone, more than 32,000 soldiers were wounded, many of them suffering serious burns from roadside bombs.
If the second trial is successful, Allen-Hoffmann said she hopes her company could release a commercial product within the next few years.
“This trial is a critical step for us,” she said.
“We will be watching closely as our patients enroll and we will look at the progression of the healing of their wounds. This will guide us and determine the speed in which we move through the regulatory process.”