First-ever pediatric feasibility study results set stage for clinical trial of world’s first bioabsorbable heart valve-enabling Endogenous Tissue Restoration

12-month follow-up data on bioabsorbable technology presented today at annual meeting of American Association for Thoracic Surgery

“Our technology is designed to enable regenerative medicine via a medical device,” says Laurent Grandidier, Xeltis AG CEO. “This is potentially a revolutionary approach in cardiovascular treatment and for the future of medicine.”

https://vimeo.com/149169508

Current cardiovascular valve or blood vessel implants are generally associated with a number of complications, have limited efficacy over time, and may necessitate repeated interventions over a patient’s lifetime, especially when implanted in a young child.
 
A team of surgeons from the Bakoulev Center for Cardiovascular Surgery, Moscow, today reported their success with implantation of bioabsorbable vascular grafts used to correct a congenital cardiac malformation in five children. Over time, the grafts are designed to biodegrade as the patients’ own cells and proteins reconstitute natural functioning tissue, thus reducing permanent implant-related complications.
 
“The positive results of the study provide hope for a new therapeutic approach in cardiovascular valve replacement called Endogenous Tissue Restoration (ETR). This is potentially a revolutionary approach to regenerative medicine in cardiovascular treatment,” says lead investigator Leo Bockeria, M.D.
 
The procedure was designed to help children born with single ventricle anomalies, a term used to describe a group of cardiac defects that shares the common feature that only one of two ventricles functions adequately. This can be due to lack of a heart valve, abnormal pumping ability of the heart, or other problems. The surgical procedure, known as a Fontan procedure, involves diverting the venous blood from the right atrium to the pulmonary arteries without passing through the area of the right ventricle.
 
In this prospective, single-center feasibility study, five children aged 4.5 to 12.5 years who were born with a single ventricle congenital malformation were implanted with a Xeltis bioabsorbable graft connecting the inferior vena cava with the right pulmonary artery during an extracardiac Fontan procedure. Patients were followed for 12 months after surgery using echocardiography, CT-scan and MRI. No device-related adverse events were reported.
 
The innovative grafts are composed of supramolecular bioabsorbable polymers, manufactured using a proprietary electrospinning process by European medical device company Xeltis. The grafts have no size limitations, although this study used grafts that were 18 and 20 mm in diameter. Histological studies of the grafts in sheep have shown that graft implantation is followed by initial infiltration of inflammatory cells, which induces physiological healing and tissue formation. This is followed by degradation of the implant scaffold with eventual reduction of the inflammatory response.
 
The investigators report that all five patients successfully recovered from the procedure, with significant improvement noted in the patients’ general condition. Imaging studies have demonstrated anatomical and functional stability of the grafts. Although longer follow-up is needed, the investigators say that the procedure has the potential to improve cardiac and vascular surgical procedures by reducing complications resulting from permanently placed implants. This is especially important for a child who must live with the after-effects of surgery over his lifetime.
 
The success of this feasibility trial has paved the way for Xeltis to develop a bioabsorbable pulmonary heart valve, which will enter clinical trials in Europe this year. Additionally, the U.S. FDA has recently granted “Humanitarian Use Device” (HUD) designation for the Xeltis bioabsorbable pulmonary heart valve for the correction or reconstruction of right ventricular outflow tract (RVOT).
  
Endogenous Tissue Restoration is enabled by the unique porous structure of the Xeltis bioabsorbable implants, which is based on Nobel Prize-awarded science. The implants are designed to harness the body’s natural healing process, to pervade them with new healthy tissue, and form complex body parts before the implants get absorbed.
 
Xeltis bioabsorbable technology has potential to reduce the risk of complications and of repeated interventions associated with currently available non-bioabsorbable synthetic or animal-derived heart valves. The technology may therefore help reduce the disease burden for patients and the overall costs for healthcare systems.