Evaluation of a Sprayable Hydrogel for Surgical Adhesion Prevention in Rat and Rabbit Models

Lauren A Costella,1 Kate Johnson,1 Rick Hassan,1 Mario Villani,2 Rosanna Villani,2 Christopher K Tison1 1Biotech Division, Luna Labs USA, LLC, Charlottesville, VA, USA; 2DaVINCI Biomedical Research Products, Lancaster, MA, USACorrespondence: Lauren A Costella, Biotech Division, Luna Labs USA, LLC, 706 Forest St, Suite A, Charlottesville, VA, 22903, USA, Tel +14342209441, Email [email protected]: To evaluate the effectiveness of a sprayable adhesion barrier in the prevention of postoperative adhesions.Methods: Established rat and rabbit models of abdominal adhesion formation were used to evaluate AeroVeil efficacy. First, 24 Sprague-Dawley rats were randomly assigned to untreated control, Seprafilm-treated, or AeroVeil-treated test groups. Defects were created on abdominal wall and cecum surfaces, with sutures around the injury perimeter to increase the likelihood of adhesion formation. Treated animals were sprayed with recommended AeroVeil dosing over both injured surfaces; a Seprafilm sheet was placed between the two injured surfaces; control animals received no treatment. Additionally, AeroVeil application was compared to untreated controls in 24 New Zealand White rabbits. The abdominal wall and cecum surfaces were abraded to induce adhesion formation. AeroVeil animals were treated with the recommended product dose over both injured tissue sites; control animals were closed without treatment.Results: The incidence, extent, and severity of postoperative adhesion formation were measured by blinded veterinary surgeons at 7 or 28 days. In the rat model, control animals formed adhesions between the cecum and abdominal wall injury sites in 7 of 8 animals. Incidence of this primary adhesion significantly reduced (p < 0.05) to 1 of 8 in Seprafilm-treated animals and 0 of 7 in AeroVeil treated animals, with similarly significant reduction in the extent and severity scores. In the rabbit model, application of AeroVeil decreased the incidence of adhesion formation, with a statistically significant decrease in total adhesion score across all tissue groups.Conclusion: AeroVeil application reduced the incidence and severity of postoperative adhesion formation in two different animal models, with results in the rat model directly compared to an established clinical control (Seprafilm). These findings justify further investigation of AeroVeil in expanded animal models to facilitate clinical translation.Plain Language Summary: A sprayable hydrogel has been demonstrated to form a barrier to postoperative adhesion formation, with effectiveness established in both rat and rabbit models.Keywords: hydrogel, postoperative adhesion, chitosan, alginate, sprayable