Military researchers are putting the final touches on a study of a "skin substitute" grown from a patient's own cells to treat complex burns and soft tissue injuries.
The new research study underway at the U.S. Army Institute of Surgical Research in San Antonio holds promise for treating burn patients, including those with severe, life-threatening wounds.
The treatment, called "engineered skin substitute," or ESS, combines tissue cultivated from a patient's skin along with collagen-producing cells to replace the two top components of skin, the epidermis and dermis.
Using the patient's cells avoids the need for foreign substitutes and lowers the chances of infection, which in turn avoids the need for immunosuppressants and reduces the number of surgeries required.
ESS is being developed by California-based biotechnology firm Amarantus BioScience and researchers from USAISR and Rutgers University.
Skin autografts — using an individual's own cells or skin to replace damaged tissue — have been around for years, but the technology for rapidly growing replacement skin to use in large-scale burn replacement has lagged.
Moreover, many current products replace either one layer of skin or the other, but not the top two layers together. A comprehensive substitute has long been the "Holy Grail of burn surgery," said Army Col. Booker King, director of the USAISR's Burn Center.
"To be able to treat a patient who has burn injuries, you have to remove the deeply burned tissue [and cover it]. Skin is complex … a burn will not heal on its own. You have to have grafting," King said.
ESS already has been designated an "orphan" drug by the FDA, to be used for investigative purposes to treat pediatric patients burned over more than 95 percent of their bodies.
King said if it works on patients at the USAISR Burn Center, it could help the rare cases — 500 to 2,000 a year — of civilian and military adult patients nationwide whose injuries include burns over more than 50 percent of their bodies.
These patients now have very few options for successful treatment, leaving them vulnerable to infections and the deadly threat of sepsis.
"Very large injuries and burns not only affect the skin and muscle, but every other organ system," King said. "You run a risk of respiratory failure, kidney failure, endocrine failure. The skin does a lot more than people realize."
From 2003 through 2014, the USAISR Burn Center treated 991 military patients, King said. With its 16 intensive care beds and 24 ward beds, it's the only burn center within the Defense Department and also the largest in Texas, treating severely injured civilians as well as military personnel.
The ESS study will involve 12 patients whose burns cover more than half the surface area of their bodies. It is a "Phase 2" trial, designed to determine the safety and effectiveness of the treatment.
Amarantus CEO Gerald Commissiong said researchers will compare ESS with different autografts, but believe their product, which has helped the most severely injured children, will work.
"We believe the … dermal and epidermal cell matrix from ESS has the potential to provide a more effective direct permanent restoration of structure and function of full thickness skin, with minimal scarring," Commissiong said.
USAISR also is researching other treatments for severe burns, including the ReCell Spray on Skin System device from British-based Avita Medical, which distributes a patient's own healthy cells, grown and suspended in an enzyme liquid, onto a wound once the damaged cells are removed.
The institute's surgeons also are exploring the science of stratigraphy — layering skin cells developed from a patient's stem cells to grow new tissue.
King declined to predict how long the ESS study will take, saying that depends on the number of patients who qualify for the study as well as their willingness — or their families' — to try something experimental.
But he said ESS could provide a treatment option for an injury where few options exist.
"This would be a major breakthrough in the field, not only treating the burns we see coming out of war but for a lot of polytrauma — soft tissue injuries that need to be covered," King said.