Jeffrey R Scott, PhD1, Corey R Deeken, PhD2. 1Brown University, C.R. Bard, Inc. (Davol), 2Covalent Bio LLC
Objective: The objective of this study was to evaluate the peritoneal tissue attachment (adhesion) characteristics and histological properties associated with a novel, fully-absorbable, poly-4-hydroxybutyrate/absorbable barrier composite mesh (Phasix™ ST), compared to a partially-absorbable, polypropylene/absorbable barrier composite mesh (Ventralight™ ST) in both small and large animal models.
Methods: In the small animal model, a single mesh (2x2cm) was unilaterally implanted within the intraperitoneal position via open surgical approach in 10 male, Sprague-Dawley rats (n=5 animals/mesh type), and evaluated at 2 weeks. In the large animal model, meshes (10x15cm ellipse) were bilaterally implanted via laparoscopic surgical approach in 8 female, Yorkshire pigs (n=4 animals/mesh type), and evaluated at 4 weeks. A single mesh type was implanted in a given animal, with meshes placed on either side of the midline. The percent mesh area covered by peritoneal tissue attachments (adhesions), attachment severity, and histological properties were recorded. Semi-quantitative scores were analyzed via non-parametric, Mann-Whitney test and presented as median ± interquartile range. Mesh area covered by peritoneal tissue attachments (adhesions) was analyzed via unpaired, two-tailed t-test and presented as mean ± standard deviation.
Results: As shown in the table below, Phasix™ ST and Ventralight™ ST meshes displayed a similar host response in both small and large animal models, with no significant differences detected between mesh types (p>0.05 in all cases). Generally, both mesh types were associated with minimal, low severity peritoneal tissue attachments (adhesions), mild/moderate inflammation, mild collagen deposition, and mild neovascularization in both small and large animal models. Although not statistically significant, a trend toward lower percent mesh area covered by peritoneal tissue attachments (adhesions) was observed for Phasix™ ST.
| RAT STUDY (n=5) | Phasix™ ST Mesh | Ventralight™ ST Mesh |
| Attachment coverage area (%) | 2.9 ± 3.9% | 13.5 ± 10.1% |
| Attachment score |
0.0 (0.0-1.0) |
1.0 (1.0-1.0) |
| Inflammation |
2.0 (2.0-2.5) |
3.0 (3.0-3.0) |
| Collagen deposition |
2.0 (2.0-2.0) |
2.0 (2.0-2.0) |
| Neovascularization |
2.0 (1.5-2.0) |
2.0 (1.5-2.0) |
| PORCINE STUDY (n=8) |
Phasix™ ST Mesh |
Ventralight™ ST Mesh |
|
Attachment coverage area (%) |
2.9 ± 2.9% | 24.6 ± 35.5% |
| Attachment score |
1.0 (0.0-1.0) |
0.5 (0.0-4.25) |
| Inflammation |
3.0 (3.0-3.0) |
3.0 (3.0-3.0) |
| Collagen deposition |
2.0 (1.25-2.75) |
2.0 (2.0-2.0) |
| Neovascularization |
2.0 (2.0-2.0) |
2.0 (2.0-2.0) |
Conclusions:
Data suggest that a novel fully-absorbable composite barrier mesh (Phasix™ ST) demonstrated a comparable short-term host tissue response to a partially-absorbable, polypropylene/absorbable barrier composite mesh (Ventralight™ ST) following implantation in both rat and porcine models.
DAV/PHST/0915/0020