T1 A Comparative Study of Autologous Skin Cell Suspension to Split-thickness Autografting in the Treatment of Acute Burns

Abstract

Split-thickness autografts (STAG) are the current standard of care for the permanent coverage of deep partial-thickness (DPT) burns. However, grafting is often complicated by hypertrophic scarring and dyspigmentation. Non-cultured, autologous, cell suspension systems are potential alternatives to autografting appropriately selected burn wounds. ReCell® is a device for the rapid, point-of-care preparation and application of non-cultured, autologous skin cells that provides an expansion ratio of 80:1 but is currently limited by US law to investigational use only. We present the results of the initial FDA approval trial for ReCell®. This was a prospective, randomized, within-patient controlled, GCP-compliant, FDA IDE trial comparing ReCell® to STAG for the treatment of acute, DPT burns in adults suffering 1–20% TBSA thermal burns. Comparable burn wounds measuring 100–320 cm2 were randomized to treatment with ReCell® vs. 2:1 meshed STAG. The co-primary effectiveness endpoints were donor site healing at 1 week (superiority) and recipient site healing at 4 weeks (non-inferiority) between the ReCell®-treated and autografted wounds. Secondary effectiveness endpoints included percent epithelialization over time, pain, and patient satisfaction. Safety endpoints included graft loss, infection, scarring, and adverse events. Data were analysed by intention-to-treat (ITT) and modified per-protocol (MPP) populations, as appropriate. A total of 101 subjects across 12 US Burn Centers were enrolled (n=101 ITT, n=83 MPP). The superiority effectiveness endpoint was met for ReCell® donor site healing in the ITT population (p=0.004), and the non-inferiority effectiveness endpoint was met at -2.4% [-8.4 to 2.3%] in the MPP population for ReCell® recipient site healing vs. STAG healing. Secondary effectiveness endpoints demonstrated similar rates of epithelialization and patient satisfaction with respect to the recipient wounds, while there was significantly reduced pain and significantly higher patient satisfaction with respect to the ReCell® donor site wounds. No demonstrable safety signal was generated. ReCell® can be used to safely treat acute, DPT, thermal burns in adults with comparable wound closure and scarring outcomes, but with significantly smaller and less painful donor sites that patients clearly prefer, when compared to conventional STAG. Using ReCell® allows the burn surgeon to “graft” a DPT burn with ~98% less skin than with conventional STAG, resulting in comparable healing, reduced pain, improved aesthetics, and increased overall patient satisfaction.