THE CIRCUMCISION NEWS LIBRARY
The Commercial Appeal Memphis, TN Copyright 1996 Tuesday, May 7, 1996 Business MEDICAL - Circumcision yielding skin for ulcerous feet Jaan VanValkenburgh The Commercial Appeal Bioengineered skin cultured from the foreskin of circumcised babies could be available by late next year to treat diabetics with chronic foot ulcers, a Smith and Nephew plc spokesman said. The skin, called Dermagraft, is a medical breakthrough, the world's first off-the-shelf bioengineered human tissue skin replacement product, said Smith & Nephew, the health care company whose North American headquarters is in Memphis. The United States market for chronic diabetic foot ulcers is estimated at more than $1 billion, Smith & Nephew said. Worldwide, it's estimated at $2.5 billion. The new skin also will be used on burn victims and ultimately could treat other skin disorders, said Marie Burke, investor relations director for Advanced Tissue Sciences, Inc. ATS developed the product. Smith & Nephew plc will market and distribute 2-by-3-inch tissues to diabetics. Each section will sell for about $375. The treatment calls for using one piece each week for eight weeks, meaning about $3,000 worth of tissue. ATS will market 4-by-7 1/2-inch tissue pieces targeted for burn centers. These will sell for about $3,000 a square foot. A baby's foreskin usually is discarded, Burke said. ATS asks new parents to sign a consent form donating it to ATS. The dermal cells are removed from the foreskin and grown in bio-absorbable mesh inside transportable cassettes. It takes four weeks for the cells to grow inside the cassette. "With one foreskin, you can grow about six football fields worth of skin through current cell culture techniques," Burke said. ATS hasn't had to ask for a foreskin since 1989, she said. Finding more is not a problem. The finished bioengineered skin product, frozen in the soft cassette, can be shipped to doctors. When needed, the doctor cuts the Dermagraft to fit the wound, then slips it out of the package, thaws it, lays it in place and covers the wound with gauze. "Diabetics lack a lot of things (such as normal collagens) for the healing process, and they exist in the living skin that we give them," Burke said. The engineered skin forms the lower layer of skin, allowing for the natural growth of the epidermis on top. Dermagraft has had a 50 percent success rate with diabetic foot ulcer patients who were part of a pivotal clinical study. Ulcers cured with Dermagraft have not recurred, Burke said. That's compared to the current practice of applying a saline solution and dry gauze to the ulcers, a process that has only an 8 to 20 percent success rate, she said. And half those healed ulcers recur within a year. Dermagraft for burn victims, called Dermagraft-TC, also has proved better than current treatments, ATS said. Dermagraft-TC has a synthetic epidermis, unlike the skin made for foot ulcer patients, and is an alternative to the cadaver skins sometimes used temporarily to cover burn victim wounds. It's better than the skin of another human being because the bioengineered skin will not be rejected by the body. Dermagraft and Dermagraft-TC have no blood vessels. Instead, the patient's vessels migrate into the new tissue. "Dermal tissue, by definition, is universal," unlike the outer layer of skin, the epidermis, Burke said. Prolonged testing of the new skin has been done on burn patients and diabetics, but Burke said Dermagraft might also work on ulcers, like bedsores, on other parts of the body and on patients who are not diabetic. Testing has begun using the same Dermagraft technology to grow cardiovascular tissue, bone tendon ligaments and cartilage, Burke said. Bioengineered cartilage is scheduled to be tested on human beings next year, she said. In 1994, Smith & Nephew and ATS combined to develop, manufacture and market engineered cartilage for orthopedic applications. Initially, it will focus on the repair or replacement of damaged articular and meniscus cartilage in the knee. ATS is working to get Dermagraft and Dermagraft-TC to market first because they both can save lives, Burke said. The Food and Drug Administration said the review process for both new skin products would be expedited. ATS will apply for FDA approval later this year for the ulcer skin product, pending the successful outcome of an ongoing clinical trial. In March, it submitted its request for approval for the skin to be used on burn victims. There are an estimated 800,000 U.S. diabetic patients with chronic foot ulcers each year, resulting in 55,000 limb amputations annually, Smith & Nephew said. The three-year survival rate for diabetes-related amputees is 50 percent. Dermagraft-TC is on schedule to be ATS's first commercial product, and Dermagraft could be its second. The public, 10-year-old tissue engineering company will be expanding into manufacturing and marketing to support its products. It now has 159 employees, 70 percent of whom are researchers, Burke said. The company is based in La Jolla, Calif., near San Diego. As part of Smith & Nephew's partnership with ATS, Smith & Nephew paid ATS $10 million up front. Smith & Nephew will pay up to an additional $60 million in incremental payments based on the achievement of certain written milestones. Smith & Nephew spokesman Betty Cole said Memphis operations would not be involved in the new product.