Phase 2/3 Trial for MPS IIIA Gene Therapy Candidate LYS-SAF302 Starts Dosing Patients

The first patient has been dosed in a Phase 2/3 clinical trial evaluating Lysogene‘s gene therapy candidate LYS-SAF302 for Sanfilippo syndrome type A, also known as mucopolysaccharidosis type IIIA (MPS IIIA).

LYS-SAF302 is a viral vector that carries a healthy SGSH gene. This gene gives instructions to produce an enzyme called sulfamidase, which is defective in Sanfilippo syndrome type A.

This gene therapy is a one-time treatment that allows the body to make the missing enzyme, which slows or halts disease progression.

The study is currently enrolling at eight centers across the U.S. and Europe. More information can be found here.

“The first patient dosed in the AAVance trial is an important step in addressing this relentlessly progressing neurodegenerative disease,” Karen Aiach, founder and CEO of Lysogene, said in a press release. “Our aim is to stabilize or improve the clinical status of patients with MPS IIIA by providing a permanent source of functional enzyme in the brain.”

According to the worldwide license and collaboration agreement between Sarepta Therapeutics and Lysogene, Sarepta holds the marketing rights for LYS-SAF302 in the U.S. and other countries outside Europe.

“Every day is an opportunity to make progress in bringing transformative treatments to patients and today’s milestone is an important advancement toward that goal,” said Doug Ingram, president and CEO of Sarepta.

“Sarepta is committed to working with Lysogene to advance this program with the greatest urgency on behalf of patients,” Aiach said.

In this open-label Phase 2/3 study (NCT03612869), known as AAVance, 20 MPS IIIA patients (6 months and older) will receive a one-time dose of the therapy. During a single session of neurosurgery and guided by real-time images, LYS-SAF302 will be injected directly to both sides of the brain. The patients will be monitored for 24 months at regular intervals for developmental and behavioral changes. Magnetic resonance imaging (MRI) scans will also be used to assess changes in brain volume.

The goal of the study is to deliver a healthy and functional copy of the SGSH gene to the brain so it can make its own functional sulfamidase enzyme and help improve or stabilize the neurodevelopmental state of MPS IIIA patients..

“It is a great motivation to know that the work we are doing here has the potential to make a life-changing difference,” said Ronald Crystal, MD, primary investigator of the study, chairman of the Department of Genetic Medicine at Weill Cornell Medicine, and a physician at NewYork-Presbyterian/Weill Cornell Medical Center. “I am very much looking forward to further advancing this innovative therapy.”