# Decellularized xenograft leaflet patch for pulmonary valve repair in pediatric patients

> **NIH NIH R41** · ANNOVIANT, INC · 2020 · $327,779

## Abstract

Congenital heart disease affects approximately 40,000 newborns each year in the U.S. Valve repairs are needed
for pulmonary valve, particularly for patients with the diagnoses of tetralogy of Fallot, tetralogy of Fallot with
absent pulmonary valve, tetralogy of Fallot with AV canal, pulmonary valvar stenosis, and pulmonary valvar
atresia. An additional group are patients with a prior repair of tetralogy of Fallot and pulmonary valvar
regurgitation. This latter group may be the largest, and currently receive bioprosthetic valves in surgically or by
catheterization. The longevity of both of these types of pulmonary valve replacements is limited. Leaflet repair
materials in current use include autologus pericardium; glutaraldehyde treated bovine pericardium, and
polytetrafluorethylene (PTFE). The limitations of these materials involve to varying degrees their
thrombogenicity, durability, susceptibility to infection, and lack of growth potential. These materials also have
varying degrees of stiffness and flexibility, which present technical challenges for surgeons, particularly in
neonates and infants where size constraints and limited space in the mediastinum combine with the relatively
thin immature native vascular tissues to create tissue-materials mechanical mismatches, which can compromise
the ability to achieve a successful surgical repair. Current clinical experience indicates that young age, in
particular, is an important risk factor for shortened intervention free survival in patients requiring these valves as
part of their initial surgical repair. The goal of creating a leaflet repair patch that will overcome these limitations
has not been achieved. We propose to develop a commercializable leaflet repair patch prototype and test the
regenerative potential of decellularized and pentagalloyl glucose (PGG) treated porcine aortic valve leaflet repair
patch with attached aortic wall (TxGuard-LP) that would repopulate with host cells and slowly regenerate and
grow with the patient without unwanted inflammation and degeneration in contrast to the existing repairing
procedures. Our specific aims for STTR Phase I are: Specific Aim 1: Evaluate TxGuard-LP for material
properties after sterilization and extended storage such as suture pull out test, biaxial mechanical testing, and
enzymatic resistance. We will also test sterility assurance level and rinsing protocols for further implantation.
Specific Aim 2: Evaluate TxGuard-LP for biocompatibility. This will include 30, 60, and 90-day subdermal
implantation in juvenile rats to assess calcification resistance, inflammatory cellular response and remodeling.
Specific Aim 3: Evaluate TxGuard-LP for functional assessment in growing lamb as a pulmonary leaflet
replacement patch for three months to assess safety, function, biocompatibility, and cellularization by the host
cells in a circulatory environment.

## Key facts

- **NIH application ID:** 10008617
- **Project number:** 1R41EB031594-01
- **Recipient organization:** ANNOVIANT, INC
- **Principal Investigator:** Naren R Vyavahare
- **Activity code:** R41 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $327,779
- **Award type:** 1
- **Project period:** 2020-09-30 → 2022-09-29

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10008617

## Citation

> US National Institutes of Health, RePORTER application 10008617, Decellularized xenograft leaflet patch for pulmonary valve repair in pediatric patients (1R41EB031594-01). Retrieved via AI Analytics 2026-05-26 from https://api.ai-analytics.org/grant/nih/10008617. Licensed CC0.

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