AXOVANT announces clinical update from first Tay-Sachs disease patient dosed with AXO-AAV-GM2 gene therapy

  • Generally well-tolerated with no serious adverse events in a 30-month-old patient with advanced infantile Tay-Sachs disease
  • Stable clinical condition from baseline to month 3 without deterioration on neurological exam
  • Increase in CSF β-Hexosaminidase A enzyme activity from baseline to month 3, surpassing the 0.5% threshold expected for a clinically important effect
  • Axovant to present at the Cowen and Company 39th Annual Health Care Conference on March 11th at 12:00 PM (Eastern Time)
  • NEW YORK and BASEL, Switzerland, March 11, 2019 (GLOBE NEWSWIRE) — Axovant (Nasdaq: AXGT), a clinical-stage company developing innovative gene therapies, today reported three-month data from an investigator-initiated study administering investigational AXO-AAV-GM2 gene therapy in a patient with advanced infantile Tay-Sachs disease, a rare and fatal pediatric neurodegenerative genetic disorder characterized by impaired β-Hexosaminidase A enzyme production. AXO-AAV-GM2 is an investigational gene therapy designed to restore β-Hexosaminidase A enzyme activity in the central nervous system. Terence R. Flotte, M.D., professor of pediatrics and dean of the School of Medicine at the University of Massachusetts Medical School, is the principal investigator leading the study under an investigator-initiated Investigational New Drug (IND) application that was cleared by the U.S. Food and Drug Administration (FDA).

    The study is evaluating a total dose of 1.0x 1014 vg of AXO-AAV-GM2 in a 30-month-old child with advanced infantile Tay-Sachs disease. AXO-AAV-GM2 was administered into the cisterna magna and lumbar spinal canal only. Due to the patient’s advanced disease, a co-delivered intrathalamic injection of AXO-AAV-GM2 was not administered. Future patients in the program, who are expected to be treated earlier in their disease course, will receive AXO-AAV-GM2 co-delivered into the thalamus bilaterally as well as into the cisterna magna and spinal canal.

    AXO-AAV-GM2 was generally well-tolerated and no serious adverse events have been reported as of the 3-month visit. At 3 months, no clinically relevant laboratory abnormalities were observed following AXO-AAV-GM2 administration.

    The patient’s clinical condition was stable from baseline to month 3 without clinical deterioration observed on neurological exam. Furthermore, there was no significant deterioration in the condition from the pre-treatment magnetic resonance imaging (MRI) of the brain at baseline to the post-treatment MRI at month 3.

    β-Hexosaminidase A activity was determined using the 4MUGS assay, the standard assay for assessing activity of the enzyme. At baseline, the patient’s enzyme activity in the cerebrospinal fluid (CSF) was 0.46% of normal. At 3 months, there was an apparent increase in enzyme activity in the CSF to 1.44% of normal, an increase surpassing the 0.5% threshold that could represent a clinically important effect. Serum β-Hexosaminidase A enzyme activity was also increased from baseline at all time points measured following administration of AXO-AAV-GM2. Additional independent assays and sampling will be conducted to further evaluate the biological activity of AXO-AAV-GM2.

    “Our first priority has been to identify a vector construct and route of delivery that can reconstitute a clinically important level of enzyme activity in a safe manner,” said Dr. Flotte. “This first demonstration of the feasibility of human gene therapy for Tay-Sachs disease is a tribute to the tremendous collaborative effort between the research teams at UMass Medical School and Auburn University, and provides a strong foundation for the transition of this program to the team at Axovant.”

    “This is the first time a gene therapy has been administered to a child with Tay-Sachs disease, and it is remarkable that we have not only seen good safety and tolerability to date, but also evidence of functional β-Hexosaminidase A enzyme activity,” said Dr. Gavin Corcoran, Executive Vice President of Research and Development at Axovant. “These encouraging early clinical results suggest that AXO-AAV-GM2 may offer a meaningful treatment option for patients who currently have no approved therapies.”

    Pavan Cheruvu, M.D., chief executive officer of Axovant, will present at the Cowen and Company 39th Annual Health Care Conference on March 11, 2019 at 12:00 PM (Eastern Time). A copy of the Company’s presentation slides and link to a live webcast of the presentation can be found below.

    About AXO-AAV-GM2

    AXO-AAV-GM2 is an investigational gene therapy for GM2 gangliosidosis (also known as Tay-Sachs and Sandhoff diseases), a set of rare and fatal pediatric neurodegenerative genetic disorders caused by defects in the HEXA (leading to Tay-Sachs disease) and HEXB (leading to Sandhoff disease) genes that encode the two subunits of the β-hexosaminidase A (Hex A) enzyme. These genetic defects lead to neurodegeneration and shortened life expectancy. AXO-AAV-GM2 aims to restore Hex A function by introducing a functional copy of the HEXA and HEXB genes via delivery of two co-administered AAVrh8 vectors.

    About Axovant

    Axovant, part of the Roivant family of companies, is a clinical-stage gene therapy company focused on developing a pipeline of innovative product candidates for debilitating neurological and neuromuscular diseases. The company’s current pipeline of gene therapy candidates targets GM1 gangliosidosis, GM2 gangliosidosis (including Tay-Sachs disease and Sandhoff disease), Parkinson’s disease, oculopharyngeal muscular dystrophy (OPMD), amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Axovant is focused on accelerating product candidates into and through clinical trials with a team of experts in gene therapy development and through external partnerships with leading gene therapy organizations. For more information, visit

    About Roivant

    Roivant Sciences aims to improve health by rapidly delivering innovative medicines and technologies to patients. It does this by building Vants – nimble, entrepreneurial biotech and healthcare technology companies with a unique approach to sourcing talent, aligning incentives, and deploying technology to drive greater efficiency in R&D and commercialization. For more information, please visit

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