Children’s Hospital in Los Angeles (CHLA) has announced its participation in the first-ever clinical trial using umbilical cord stem cells to treat newborn babies with a rare congenital heart defect.
The condition, known as hypoplastic left heart syndrome (HLHS), leaves the patients’ left ventricle significantly underdeveloped and is fatal without surgical intervention.
The Phase 1 study will test the hypothesis that stem cells taken from a newborn’s umbilical cord blood can stimulate the growth of heart muscle, combining pioneering surgical techniques with regenerative medicine.
Current treatment options
As it is normally the left ventricle that is thick with muscle, the right is often smaller and as such ill-equipped to cope with the ‘double duty’ required of it by HLHS patients. Corrective surgery for HLHS usually occurs within the first three years of the child’s life and focuses on making the right ventricle the main pumping chamber.
CHLA first performed HLHS surgery in 1992, however when patients reached adolescence doctors found their reconstructed hearts were deteriorating. For some, this led to heart failure and the need for a heart transplant.
The clinical trial hopes to strengthen HLHS patients’ right ventricle through the injection of stem cells. In this way the trial aims to delay or event prevent heart failure in those with the condition.
“This is one of the earliest efforts at harnessing the power of stem cell technology for the care of children with a serious cardiac disease,” said the head of CHLA’s HLHS study Dr Ram Kumar Subramanyan.
The newborns participating in the trial will have their umbilical cord blood collected and sent to the Mayo Clinic, where stem cells will be removed. Within a few hours of birth the baby will be taken to CHLA, where they will undergo their first HLHS surgery two to five days later.
At six months, the baby will undergo the Glenn procedure – the second open-heart surgery. During this, the child’s own stem cells are thawed and injected back into their heart. The hope is that the stem cells will stimulate growth in the heart muscle during the critical first year of life, when cardiac cells are able to proliferate. The third surgery takes place when the child is three years old, and is known as the Fontan procedure.
All children enrolled in the study will be monitored over the long term to discern the success of the procedure.
The HLHS Consortium hopes to recruit around 20 children for the Phase I study, with CHLA already enrolling several families.
The HLHS Consortium
The study is a part of a multi-centre collaboration dedicated to finding innovative therapies to improve outcomes for children with HLHS.
The HLHS Consortium was first launched at the Mayo Clinic in Minnesota in 2017 and consists of four regional centres. Members include the Children’s Hospital of Philadelphia and Minnesota Children’s Hospital as well as Sisters by Heart, the largest HLHS non-profit in the US.
“As a leading centre for medical and surgical treatments for HLHS, we want to be at the forefront of the next transformative therapy for this complex condition,” said co-director of the Heart Institute at CHLA, Vaughn Starnes.
If successful, the trial will be a ground-breaking step in neonatal care and stem cell surgery. Preclinical research has already suggested that stem cells could offer a chance of treating other neonatal disorders such as bronchopulmonary dysplasia and intraventricular hemorrhage in preterm newborns. Indeed, there is much hope that stem cells will be a source of treatment for a range of conditions, though many developments remain in the trial stages.