The superiority of fish-skin xenografts over dehydrated human amnion/chorion allografts (dHACM) for the treatment of acute wounds has been established in a randomised controlled trial published in Wound Repair Regeneration. Conducted by Robert Kirsner (University of Miami Miller School of Medicine, Miami, USA) et al, using Kerecis’ “Omega3 Wound” product, the investigation found that full-thickness acute wounds treated with fish skin grafts heal significantly faster than wounds treated with dHACM.
In terms of healthcare resources and consequences for the patient, chronic wounds can be incredibly costly and, according to Kirsner and colleagues, represent “a major public health problem” that must be addressed. Skin grafts—either from the patient’s own skin, a human donor, or another species—are a common treatment for these hard-to-heal wounds and, in recent studies—fish skin xenografts from cold-water fish (such as Atlantic cod) have achieved promising clinical results.
As a response to this success, Kirsner and colleagues conducted a trial which aimed to determine the efficacy of “two therapeutic alternatives”—the fish-skin xenograft and dHACM—in the treatment of freshly debrided chronic wounds, imitated in this study by 4mm full-thickness biopsies.
Oscar M Alvarez (University Hospital; Rutgers New Jersey Medical School, Newark, USA), speaking at the Symposium on Advanced Wound Care Fall meeting (SAWC Fall 2019; 12-14 October, Las Vegas, USA), gave an overview of the study, explaining that the biopsies were performed on healthy volunteers only. “Each volunteer received two biopsies; one which was treated with the fish-skin graft, while the other was treated with a dHACM,” he said, describing the method of the investigation.
With the primary endpoint established as to time to healing (full epithelialisation) for both types of skin graft, and a superiority hypothesis formed that the fish-skin product would be faster in terms of time to healing compared to dHACM, volunteers between the ages of 19 and 51 years were recruited over a two-month period, before receiving two acute wounds that were randomized to either treatment with Kerecis’ fish-skin graft or the dHACM.
Two physicians were said to have conducted the study, with the first—a trial physician—applying the products, and the second—a blinded evaluating physician—observing the results and assessing wounds only. In addition, three further reviewers (all of whom were blinded) examined photographs taken of the wounds and determined the visit at which the wound had fully healed.
In total, 170 wounds were treated and assessed across the 85 volunteers, none of whom were lost to follow-up. Results of the trial showed that, from day 14 onward, wounds in the group treated with fish skin healed both to a greater extent on average than wounds treated with dHACM, and significantly faster as well (hazard ratio 2.37; 95% CI: 1.75–3.21 [p=0.0014]). These findings confirmed the investigators’ original superiority hypothesis, and there was no difference in the number of adverse reactions (including mild erythema or irritation) between both groups.
Commenting on the results of the study in his presentation at SAWC Fall 2019, Alvarez said: “This is interesting, in that acute wound trials are a lot easier to conduct and they give you a pretty solid endpoint, as well as good data that you can count on. However, we are not treating chronic wounds here, but rather wounds that would heal normally.”
Investigators of the trial also highlighted limitations in their research, stating that while “fish skin has been shown to improve time to closure”, the “routine need for reapplication for these products in clinical settings, and the nature of the chronic wound patient, cannot be reflected in this study design. They concluded: “Overall, the product has shown superiority in this particular model; however, clinical trials on chronic wounds are required to further validate these results.”