ABO-102 Gene Therapy | Type IIIA | Phase I-II | Ultragenyx

Page reviewed by: Dr. Cara O’Neill, FAAP Page last updated: July 29, 2022 For web accessibility options: Click/tap the floating blue icon on the right.

The ABO-102 Gene Therapy uses a self-complementary adeno-associated virus serotype 9 carrying the human SGSH gene under the control of a U1a promoter (scAAV9.U1a.hSGSH) delivered one time through a venous catheter inserted into a patient’s peripheral limb vein. A tapering course of prophylactic enteral prednisone or prednisolone is administered for a period of at least two months. There are two studies using the ABO-102 gene therapy product: ABT-001 and ABT-003. In May 2022, Ultragenyx acquired global rights to AAV Gene Therapy ABO-102 for Sanfilippo Syndrome Type A (MPS IIIA) from Abeona Therapeutics. This means Ultragenyx is assuming responsibility for the ABO-102 program. Learn more.

Study ABT-001:

Phase I/II Gene Transfer Clinical Trial of scAAV9.U1a.hSGSH

Status: Active

Study sites are in the following countries: United States, Australia, and Spain. More than 20 patients have been treated in this study, so far. Enrollment remains open at this time for the revised eligibility criterial cohort (Transpher A). Revised eligibility criteria is limited to patients less than 2 years of age or greater than or equal to 2 years of age with a developmental quotient of greater than or equal to 60. Read this clinical trial’s information on ClinicalTrials.gov, which includes enrollment criteria, trial locations, and study contact information.

Recent press releases regarding this therapy

• New Positive Phase 1/2 Interim Data Presented at WORLDSymposium™ Shows Neurocognitive Development of Young MPS IIIA Patients Preserved up to Three Years Following Treatment with Abeona’s ABO-102 Gene Therapy

Study ABT-003:

Gene Transfer Study of ABO-102 in Patients With Middle and Advanced Phases of MPS IIIA Disease

Status: Study Terminated

This study has been closed for enrollment as of March 11, 2022. This study focused on older children who did not qualify under ABT-001’s more narrow inclusion criteria. The company states that testing has not revealed improvement in cognitive outcomes after treatment for this group of children and that the study doctors did not feel that the benefit outweighed the potential risks. Based on these factors and business related decisions, Abeona has decided to close this study for enrollment. Patients in the study will still have safety follow up at their local doctors offices. How does this information translate to our understanding of the benefit of gene therapy for Sanfilippo syndrome?

• While early results indicate that cognitive outcomes did not improve, we do not yet know all of the results of the study or if other aspects and symptoms of the disease were impacted by the treatment.
• This study tested a particular type of gene therapy at a particular dose, meaning that we do not know if different versions of a gene therapy (variation in promotor, transgene, vector, etc) or different doses could result in more beneficial outcomes for patients in the future.
• It is important to remember that there were a small number of patients in this particular study which limits our ability to understand how a larger group of patients might respond.
• This study was designed to treat children who had already experienced significant cognitive decline due to their disease, hence we can only understand the study findings in terms of this specific population. For example, this study cannot tell us how children who have a slower disease progression and preserved cognitive function at later ages would respond to the therapy.

Read this clinical trial’s information on ClinicalTrials.gov, which includes enrollment criteria, trial locations, and study contact information.