Taysha Receives Orphan Drug Designation from the European Commission for TSHA-102 for the Treatment of Rett Syndrome

DALLAS – Taysha Gene Therapies, Inc. (Nasdaq: TSHA), a patient-centric, pivotal-stage gene therapy company focused on developing and commercializing AAV-based gene therapies for the treatment of monogenic diseases of the central nervous system (CNS) in both rare and large patient populations, today announced that it has been granted orphan drug designation from the European Commission for TSHA-102, an AAV9-based gene replacement therapy in development for Rett syndrome.

“The receipt of orphan drug designation from the European Commission represents an important regulatory milestone that has the potential to expedite the global clinical development of TSHA-102, a one-time gene therapy with disease modifying potential,” said RA Session II, President, Founder and Chief Executive Officer of Taysha. “Promising preclinical data demonstrate that TSHA-102’s novel self-regulatory feedback mechanism, miRARE, has the ability to regulate MECP2 expression in a genotype-dependent manner on a cell-by-cell basis. We are highly encouraged that this novel treatment approach can help effectively address a disease that has historically been difficult to treat, and we look forward to submitting an IND/CTA in the second half of this year and initiating a Phase 1/2 clinical trial by year-end.”

Rett syndrome is a severe genetic neurodevelopmental disorder caused by a mutation in the X-linked MECP2 gene essential for neuronal and synaptic function in the brain. Primarily occurring in females, Rett syndrome is one of the most common genetic causes of severe intellectual disability worldwide, with a prevalence of over 25,000 in the United States and European Union. Patients have normal early development, with symptom onset typically beginning between six to 18 months of age. Rett syndrome is characterized by rapid developmental regression that leads to intellectual disabilities, loss of speech, loss of purposeful use of hands, loss of mobility, seizures, cardiac impairments and breathing issues. Currently, there are no approved therapies.

TSHA-102 is a self-complementary intrathecally delivered AAV9 gene replacement therapy under development for the treatment of Rett syndrome. TSHA-102 delivers the MECP2 gene, which includes the novel miRNA-Responsive Auto-Regulatory Element (miRARE), to regulate MECP2 expression in a genotypic-dependent manner on a cell-by-cell basis. The miRARE technology is designed to prevent toxicity associated with overexpression of MECP2.

Positive preclinical data for TSHA-102 in Rett syndrome recently published in Brain provide quantitative evidence of miRARE’s ability to exhibit genotype-dependent regulation of MECP2 gene expression on a cell-by-cell basis across different regions of the brain in both wild type and knockout mouse models of Rett syndrome. TSHA-102 has previously received rare pediatric disease designation and orphan drug designation from the U.S. Food and Drug Administration (FDA). Submission of an IND/CTA filing for TSHA-102 is expected in the second half of 2021, with initiation of a Phase 1/2 clinical trial by year-end 2021.

The European Commission grants orphan drug designation for medicines being developed for the diagnosis, prevention or treatment of treat life-threatening or chronically debilitating conditions that affect fewer than five in 10,000 people in the European Union. Orphan designation in the European Union includes benefits such as protocol assistance, reduced regulatory fees and market exclusivity.

About Taysha Gene Therapies

Taysha Gene Therapies (Nasdaq: TSHA) is on a mission to eradicate monogenic CNS disease. With a singular focus on developing curative medicines, we aim to rapidly translate our treatments from bench to bedside. We have combined our team’s proven experience in gene therapy drug development and commercialization with the world-class UT Southwestern Gene Therapy Program to build an extensive, AAV gene therapy pipeline focused on both rare and large-market indications. Together, we leverage our fully integrated platform—an engine for potential new cures—with a goal of dramatically improving patients’ lives. More information is available at www.tayshagtx.com.


Company Contact:
Kimberly Lee, D.O.
SVP, Corporate Communications and Investor Relations
Taysha Gene Therapies
[email protected]

Media Contact:
Carolyn Hawley
Canale Communications
[email protected]