The US Food and Drug Administration (FDA) has approved a novel regenerative therapy that could be an alternative to autografting for treating adults with severe burns. The new treatment, StrataGraft, is a bilayer tissue engineered to mimic the epidermal and dermal layers of the human skin and act as a scaffold for a burn patient’s own skin cells to grow and heal.
The approval was based on the results of two randomized clinical trials (NCT01437852 and NCT03005106) that demonstrated the effectiveness and safety of StrataGraft in 101 adult patients with deep partial thickness thermal burns. These are burns caused by contact with an external heat source such as steam that results in damage throughout the epidermis and dermis.
Treating these burns usually involves an autograft, in which the patient’s burned skin is removed and replaced with a skin graft surgically harvested from an uninjured site elsewhere on the patient’s body. StrataGraft may reduce or eliminate the need for an autograft altogether.
In both trials, each patient acted as both subject and control. Surgeons identified two deep partial thickness thermal burns of comparable area and depth after excision on each patient. Each burn was randomly selected to receive either a single topical application of StrataGraft or an autograft. The two major outcome measures were the percentage of patients treated with StrataGraft who required an autograft at 28 days’ follow-up and wound closure of treatment sites at 3 months’ follow-up.
In the open-label, phase 1b trial of 30 burn patients, no StrataGraft treatment sites underwent autografting at 28 days. Moreover, 93% of the treatment sites had closed by 3 months.
In the the pivotal phase 3 trial, STRATA2016, StrataGraft eliminated the need for autografting for 68 of 71 patients. Upon follow-up at 3 months, 92% of StrataGraft-treated wounds had closed.
“This approval could lead to a significant decrease in mortality for burn patients, shortened hospital stays, and could also possibly decrease some of the long-term consequences of burns — especially the scarring,” Philip Chang, MD, a burn surgeon at the William Randolph Hearst Burn Center, New York–Presbyterian Hospital, New York City, told Medscape Medical News in an interview. He was not involved in the clinical trials for StrataGraft.
The most common side effect in both trials was pruritus. There were no cases of rejection of StrataGraft. Because mouse cells were used early in the development of StrataGraft, the FDA cautioned that there may be a risk for infectious disease transmission. No such cases have been observed.
“It is a theoretical risk. That risk is extremely low,” said Chang.
Previous skin substitutes had the disadvantage of being a monolayer tissue, rather than a bilayer tissue like StrataGraft.
“It takes the body anywhere from 2 to 4 weeks or longer to incorporate these monolayer templates before they can be grafted upon the wound. Oftentimes, patients with large-burden injuries would die in the time it takes for these templates to incorporate,” Chang said. With its potential to be deployed quickly, the Department of Homeland Security’s Biomedical Advanced Research and Development Authority has expressed interest in StrataGraft as a medical countermeasure for mass casualty burn events.
StrataGraft was developed by Stratatech and Mallinckrodt Pharmaceuticals with funding from the Biomedical Advanced Research and Development Authority. Chang has disclosed no relevant financial relationships.
Anna Goshua is a reporting intern with Medscape. She is a dual medical and journalism student who has previously written for STAT, Scientific American, Slate, and other outlets. She can be reached at [email protected] or @AnnaGoshua.
For more news, follow Medscape on Facebook, Twitter, Instagram, and YouTube.