FDA Panel Backs Skin Substitute for Burn Grafts.
At a meeting of the Food and Drug Administration's General and Plastic Surgery Devices Panel, members generally agreed that the data from a 6-month study presented by the manufacturer, Ortec International Inc. of New York, provided reasonable assurance of the safety and efficacy of the product, which contains human keratinocytes and fibroblasts.
The FDA usually follows the non-binding recommendations of advisory panels.
The company calls the product "composite cultured skin" and plans to market it as OrCel. It was approved previously under a humanitarian device exemption for use in hand reconstruction and donor sites in patients with skin loss due to epider-molysis bullosa.
OrCel contains human fibroblast and keratinocytes derived from neonatal foreskin and enclosed in a gel-coated, bovine collagen sponge. It conforms to the shape of the wound, adheres to the wound when applied, provides for fluid evaporation, and "minimizes wound pain," according to the company.
The panel stipulated that the following must be included in the product labeling:
* In the preapproval study the rate of healing was not significantly different in OrCel-treated sites and active-control treated sites in patients aged 12 years and younger and in those with burns affecting less than 20% of total body surface.
* The product has not been evaluated in patients with sepsis, insulin-dependent diabetes, or severe inhalation injuries, and in those taking oral steroids within 30 days.
Ortec presented the panel with results of a prospective, multicenter, randomized study comparing healing rates of split-thickness donor sites treated with OrCel or Biobrane-L, a semipermeable collagen membrane used as an active control in 82 patients with burns that covered 10%-80% of their total body surface area.
Serving as their own controls, each patient had one donor site treated with OrCel and another treated with the control.
The primary effectiveness end point was the time to complete closure of the donor site wound, defined as 100% reepithelialization with no surface moisture and no dressing needed, as evaluated by independent experts who were blinded to the treatments and viewed photographs of the wounds.
OrCel-treated sites healed in a median of 15 days vs. 22 days for control-treated sites, a significant difference. Burn scar scores at 12 weeks were statistically in favor of OrCel, but the panel agreed that these were not clinically significant.
About 37% of patients in the trial were on oxandrolone--an anabolic steroid sometimes used to increase donor site wound healing--which could have had a substantial impact on the outcome, remarked panel member Dr. Joseph Boykin, medical director of the wound healing center at Virginia Commonwealth University, Richmond.
Safety outcomes were comparable in the OrCel and control groups. There was one infection at an OrCel-treated site and one at a control-treated site.
Although the panel was comfortable with the safety data, it had concerns about the lack of histologic data and the possibility that donor cells may be retained in the wound. The company plans to do histologic studies.
OrCel is being studied in patients with venous statis ulcers and diabetic ulcers.
Ortec is considering trials in patients with decubitus ulcers and in cosmetic applications such as scar revision.