TSHA Taysha Gene Therapies Inc

Taysha Gene Therapies, Inc. (Nasdaq: TSHA) (Taysha or the Company), a clinical-stage biotechnology company focused on advancing adeno-associated virus (AAV)-based gene therapies for severe monogenic diseases of the central nervous system (CNS), today announced that it will present previously disclosed clinical data on its TSHA-102 program in evaluation for Rett syndrome during an oral presentation at the upcoming 9th World Rett Syndrome Congress, taking place in Queensland, Australia from October 2-5, 2024.

The presentation will entail previously disclosed positive clinical data up to 52 weeks from the ongoing REVEAL Phase 1/2 adolescent and adult trial and initial clinical data up to 22 weeks from the REVEAL Phase 1/2 pediatric trial evaluating TSHA-102 in Rett syndrome. The Company expects to provide clinical data from cohort two (high dose, n=3) and a longer-term update on clinical data from cohort one (low dose, n=2) from both the adolescent and adult, and the pediatric REVEAL trials in the first half of 2025.

Oral presentation details are as follows:

Abstract Title: First cohort data from the REVEAL adolescent/adult and pediatric studies of TSHA-102 gene therapy for Rett syndrome

Presenter: Sukumar Nagendran, M.D., President and Head of Research and Development at Taysha Gene Therapies

Session: Preclinical and Clinical Stream

Date & Time: Friday, October 4, 2024, from 12:40-1:00 PM Australian Eastern Standard Time (AEST)

Additional details on the meeting can be found at the 9th World Rett Syndrome Congress website.

About TSHA-102TSHA-102 is a self-complementary intrathecally delivered AAV9 investigational gene transfer therapy in clinical evaluation for Rett syndrome. Designed as a one-time treatment, TSHA-102 aims to address the genetic root cause of the disease by delivering a functional form of MECP2 to cells in the CNS. TSHA-102 utilizes a novel miRNA-Responsive Auto-Regulatory Element (miRARE) technology designed to mediate levels of MECP2 in the CNS on a cell-by-cell basis without risk of overexpression. TSHA-102 has received Regenerative Medicine Advanced Therapy, Fast Track and Orphan Drug and Rare Pediatric Disease designations from the FDA, Orphan Drug designation from the European Commission and Innovative Licensing and Access Pathway designation from the Medicines and Healthcare products Regulatory Agency.

About Rett SyndromeRett syndrome is a rare neurodevelopmental disorder caused by mutations in the X-linked MECP2 gene encoding methyl CpG-binding protein 2 (MeCP2), which is essential for regulating neuronal and synaptic function in the brain. The disorder is characterized by loss of communication and hand function, slowing and/or regression of development, motor and respiratory impairment, seizures, intellectual disabilities and shortened life expectancy. Rett syndrome progression is divided into four key stages, beginning with early onset stagnation at 6 to 18 months of age followed by rapid regression, plateau and late motor deterioration. Rett syndrome primarily occurs in females and is one of the most common genetic causes of severe intellectual disability. Currently, there are no approved disease-modifying therapies that treat the genetic root cause of the disease. Rett syndrome caused by a pathogenic/likely pathogenic MECP2 mutation is estimated to affect between 15,000 and 20,000 patients in the U.S., EU, and U.K.

About Taysha Gene TherapiesTaysha Gene Therapies (Nasdaq: TSHA) is a clinical-stage biotechnology company focused on advancing adeno-associated virus (AAV)-based gene therapies for severe monogenic diseases of the central nervous system. Its lead clinical program TSHA-102 is in development for Rett syndrome, a rare neurodevelopmental disorder with no approved disease-modifying therapies that address the genetic root cause of the disease. With a singular focus on developing transformative medicines, Taysha aims to address severe unmet medical needs and dramatically improve the lives of patients and their caregivers. The Company’s management team has proven experience in gene therapy development and commercialization. Taysha leverages this experience, its manufacturing process and a clinically and commercially proven AAV9 capsid in an effort to rapidly translate treatments from bench to bedside. For more information, please visit www.tayshagtx.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “anticipates,” “believes,” “expects,” “intends,” “projects,” “plans,” and “future” or similar expressions are intended to identify forward-looking statements. Forward-looking statements include, but are not limited to, statements concerning the potential of TSHA-102 and Taysha’s other product candidates, to positively impact quality of life and alter the course of disease in the patients Taysha seeks to treat, its research, development and regulatory plans for its product candidates, including the anticipated timelines for reporting data for the TSHA-102 REVEAL trials and the trial design of the TSHA-102 REVEAL trials, the potential for these product candidates to receive regulatory approval from the FDA or equivalent foreign regulatory agencies, and whether, if approved, these product candidates will be successfully distributed and marketed and the potential market opportunity for Taysha’s product candidates. Forward-looking statements are based on management’s current expectations and are subject to various risks and uncertainties that could cause actual results to differ materially and adversely from those expressed or implied by such forward-looking statements. Accordingly, these forward-looking statements do not constitute guarantees of future performance, and you are cautioned not to place undue reliance on these forward-looking statements. Risks regarding Taysha’s business are described in detail in its SEC filings, including in Taysha’s Annual Report on Form 10-K for the full-year ended December 31, 2023 and Quarterly Report on Form 10-Q for the quarter ended June 30, 2024, which are available on the SEC’s website at www.sec.gov. Additional information will be made available in other filings that Taysha makes from time to time with the SEC. These forward-looking statements speak only as of the date hereof, and Taysha disclaims any obligation to update these statements except as may be required by law.

Company Contact:Hayleigh Collins Director, Head of Corporate Communications and Investor RelationsTaysha Gene Therapies, Inc.hcollins@tayshagtx.com

Media Contact:Carolyn HawleyInizio EvokeCarolyn.hawley@inizioevoke.com