Helping the body to regrow damaged organs may sound like science fiction, but researchers in Switzerland say they’ve done just that.
The medical device company, Xeltis, is working with bioabsorbable
materials. These materials act as scaffolding to help the body restore
complex parts or organs using the patient’s own tissue. The porous structure of
the scaffolding provides anchor points for healthy tissue to grow in a
processes known as Endogenous Tissue Restoration. Once the healthy tissue is in
place, the scaffolding is absorbed back into the body.
On Tuesday, researchers announced that they had successfully
implanted bioabsorbable pulmonary heart valves into three children as part of
their Xplore-I clinical feasibility study. Researchers are hopeful that the
valves will grow and work as intended.
Results of an earlier clinical trial, announced Wednesday,
give them reason for optimism. In that trial, bioabsorbable cardiovascular
conduits implanted into patients were still functioning well two years after
That trial followed five patients aged 4 to 12 years at the
time of surgery. The patients had only one functioning ventricle. The
bioabsorbable conduits redirected blood to reduce stress on the heart, a common
procedure in patients with congenital heart defects.
According to the Centers for Disease Control and Prevention,
about 40,000 babies with heart defects are born in the United States each year.
About 25 percent of those babies have a critical heart defect which will
require surgery within the first year of life. Many will require multiple
surgeries as they grow.
Dr. Alistair Philips, Co-Chair of the American College of
Cardiology Surgeons’ section called, the technology exceptionally encouraging.
“Being able to develop a procedure and
have a valve that’s going to grow with the child will be exceptionally valuable
for those children,” Phillips said. “They won’t have to come back for a second
The study is
the first clinical trial in which the Xeltis bioabsorbable pulmonary valve has
been implanted into patients. It is the first-ever cardiac valve made entirely
of bioabsorbable polymers and the first to enable the heart to essentially
“While Xeltis’ products get
bioabsorbed in the body, they enable formation of new tissue that is expected
to last longer than the existing products available today,” said Laura Monti
Head of Communications at Xeltis.
Currently, doctors have two
options when treating patients with congenital heart defects that require heart
valve replacement. Either they use valves transplanted from organ donors, or
they create a pulmonary conduit out of animal tissue.
“The problem with those
valves is they will fail within five months to six years, and [patients] are
going to have to come back,” Phillips said. “If there’s a valve that will grow
with the child, that doesn’t have to be replaced, that’s the ideal.”
The Xplore-I trial will
include as many as twelve patients aged 2 to 21 years old, Monti said. Those
patients, along with the three who have already received the new implant, will
be monitored over the course of five years to assess the functionality of the
If the preclinical trial is a
success, the device will move on to clinical trials. The US Food and Drug
Administration has already granted Xeltis a Humanitarian Use Device Designation
for the pulmonary valve.
The HUD designation is
granted to medical devices that may help people with diseases affecting less
than 4,000 individuals in the United States per year. Under this designation,
the company only has to prove the safety of the product, they do not have to
prove that it is effective. This enables companies to release a treatment even
when it’s impossible to find enough patients to enroll in a clinical trial.
Phillips said that the technology presented by Xeltis may
have an impact far beyond the treatment of congenital heart defects.
Bioabsorbable implants may help repair heart valves in adults, build a new esophagus,
or regrow skin for burn victims.
“It could be very beneficial to medicine as a whole,”
Phillips said, “We’re going to see a lot more of this.”