New grant expands reach of St. Jude gene therapy program for 'bubble boy' disease

The California Institute for Regenerative Medicine has awarded a five-year, $11.9 million grant to St. Jude Children's Research Hospital and collaborators to deliver gene therapy to patients with X-linked severe combined immunodeficiency disease (X-linked SCID), also known as "bubble boy" disease.

The new grant supports the opening of the St. Jude gene therapy protocol for X-linked SCID at the University of California, San Francisco (UCSF) Benioff Children's Hospital San Francisco. The bone marrow transplant program at UCSF is one of the largest SCID transplant centers in North America.

"We have made good progress in demonstrating the safety and efficacy of our lentiviral-based gene therapy for the treatment of X-linked SCID," said Brian Sorrentino, M.D., principal investigator on the grant and a member of the St. Jude Department of Hematology. "One of our goals with this new collaboration is to widen access to this life-saving gene therapy pioneered at St. Jude. We want to rebuild the immune systems of even more patients who suffer from this rare but deadly immune disease."

X-linked SCID is an inherited disorder that involves a mutation in one of the genes necessary for a normal immune system. It occurs in one of every 200,000 live births. Babies born with X-SCID lack immune cells known as lymphocytes, which leaves them with little or no immune protection.

The lentiviral gene vector developed at St. Jude delivers a functional gene into the patient's blood-producing stem cells. After infecting the cells, the virus transports the healthy gene to the patient's cells. Over the past decade, St. Jude scientists have developed a rigorous battery of tests to assess the viral vector's safety. Working with UCSF investigators, they were granted approval for the first time to use the chemotherapy drug busulfan as part of the SCID-X1 gene therapy protocol to help the gene-corrected cells establish themselves in the bone marrow and get to work after being infused back into SCID-X1 patients. The team went on to build an entirely new process for manufacturing the vector in the Children's GMP, LLC, an on-site facility that produces biological products and drugs in accordance with federal safety regulations.

"It is rewarding to see the benefits of years of pre-clinical development come to fruition for the team that has worked to develop the protocol for this gene therapy," said Sorrentino. "We are grateful to the California Institute for Regenerative Medicine for this additional funding, which will help bring our protocol to X-linked SCID patients treated in California. We look forward to working with the team at the UCSF Benioff Children's Hospital San Francisco in the years ahead. "

Provided by St. Jude Children's Research Hospital