First Wilson Disease patient receives gene therapy at UC Davis Health

Wilson Disease, a rare genetic disorder with no cure, has evaded comprehensive treatment for generations of patients. Untreated Wilson Disease can cause liver failure, neurologic and psychiatric symptoms and is ultimately fatal.

However, researchers at UC Davis Health have infused their first Wilson Disease patient with a gene therapy as part of a groundbreaking new clinical trial. The treatment has the potential to address the underlying cause of the disease.

Wilson Disease is an inherited condition that causes the body to retain excess copper. The liver of a person who has Wilson Disease does not release copper into bile as it should. This leads to copper overload in the liver, release of copper into the blood, and the damaging accumulation of copper in the brain and other organs. Patients must eat a restrictive diet in order to avoid foods that contain copper. 

According to the National Liver Foundation, about one in 30,000 people have Wilson Disease.

“Current treatment options for Wilson Disease involve the often complicated and lifetime use of medications,” said Valentina Medici, vice chair for research in internal medicine and principal investigator for the trial. “Additionally, these treatments just control the disease and do not cure it. Finding a treatment that could address the underlying cause would tremendously improve the quality of life for patients suffering from the disease.”

By finding a treatment that could address the underlying cause would tremendously improve the quality of life for patients suffering from the disease.”—Valentina Medici

Gene therapy clinical trial

The industry-funded clinic trial with Ultragenyx is evaluating UX701, an investigational adeno-associated virus (AAV) vector-based gene therapy. UC Davis Health is one of just seven health care institutions worldwide to infuse a patient with this new gene therapy for the Ultragenix trial so far.

The gene therapy treatment aims to deliver stable expression of the ATP7B copper transporter, which plays a role in the regulation of copper homeostasis in the liver by delivering copper to the secretory pathway and mediating export of excess copper into the bile, following a single intravenous infusion. The goal of the infusion is to normalize copper metabolism in patients with Wilson disease.

“This therapy delivers the gene to the liver to replace the copper transporter that is mutated and allows the liver to function properly so it can eliminate accumulated copper,” explained Medici. “If successful, this one-time treatment will correct the underlying defect and allow patients to stop their oral medications.”

Positive results for patient

Upon receiving the novel treatment at the Clinical Research Center, the Wilson Disease patient treated at UC Davis Health has seen improvement in symptoms associated with the disorder. The patient should be able to return to a normal diet instead of the restrictive one that Wilson Disease patients undertake due to complications associated with copper buildup in the body.

Medici and her team of clinical research coordinators from the Hepatology Clinical Trial Unit will continue to follow the patient for five years through telemedicine visits and in-person appointments.

“We are encouraged by the safe administration of the gene therapy and promising preliminary results, but the same success needs to be seen in more patients before the treatment can be approved,” said Medici.

The clinical trial aims to enroll a total of 15 patients in this phase and follow them for several years before there is enough data to apply for approval.