REVEAL adolescent and adult trial will proceed to high dose cohort following Independent Data Monitoring Committee approval of Company’s request to initiate dose escalation; dosing of first patient in cohort two (high dose, n=3) expected in Q2 2024

REVEAL青少年和成人试验将在独立数据监测委员会批准公司启动剂量递增的请求后进行高剂量队列研究；预计2024年第二季度第二组（高剂量，n=3）中第一名患者的剂量

REVEAL adolescent and adult trial will now expand into the U.S. following submission to FDA (age 12+ protocol)

在提交给FDA（12岁以上协议）后，REVEAL青少年和成人试验现在将扩展到美国

Dosing of second patient in cohort one (low dose) of REVEAL pediatric trial expected in Q1 2024 following Independent Data Monitoring Committee approval

独立数据监测委员会批准后，预计2024年第1季度REVEAL儿科试验队列1（低剂量）中第二名患者的剂量

Update on available clinical data from completed cohort one (low dose, n=2) in REVEAL adolescent and adult trial expected in Q1 2024; initial data from cohort one in REVEAL pediatric trial expected mid-2024; initial data from cohort two (high dose) in both trials expected in second half of 2024

2024年第1季度REVEAL青少年和成人试验中已完成队列一（低剂量，n=2）的可用临床数据更新；REVEAL儿科试验中队列一的初始数据预计在2024年年中；预计2024年下半年两项试验中第二组（高剂量）的初始数据

DALLAS, Feb. 29, 2024 (GLOBE NEWSWIRE) -- Taysha Gene Therapies, Inc. (Nasdaq: TSHA) (“Taysha” or “the Company”), a clinical-stage gene therapy company focused on developing and commercializing AAV-based gene therapies for the treatment of severe monogenic diseases of the central nervous system (CNS), today announced updates to its TSHA-102 program in clinical evaluation for the treatment of Rett syndrome.

达拉斯，2024年2月29日（环球通讯社）--Taysha Gene Therapeutics，Inc.（纳斯达克：TSHA）（“Taysha”或“该公司”），一家临床阶段基因治疗公司，专注于开发和商业化基于AAV的基因疗法，用于治疗中枢神经系统（CNS）的严重单基因疾病，今天宣布更新其TSHA-102治疗Rett综合征的临床评估计划。

The Independent Data Monitoring Committee (IDMC) approved the Company’s request to proceed to dose escalation in the REVEAL Phase 1/2 adolescent and adult trial, enabling earlier advancement to the high dose cohort of 1x1015 total vg. The IDMC also approved the dosing of the second patient in cohort one (low dose) of 5.7x1014 total vg in the REVEAL Phase 1/2 pediatric trial.

独立数据监测委员会（IDMC）批准了该公司在REVEAL 1/2期青少年和成人试验中进行剂量递增的请求，从而能够更早地进入总vg为1x1015的高剂量队列。IDMC还批准了REVEAL 1/2期儿科试验中队列1（低剂量）中总vg为5.7x1014的第二名患者的剂量。

The decisions follow IDMC review of available clinical data from the patients dosed with TSHA-102. The Company also announced the expansion of its ongoing REVEAL Phase 1/2 adolescent and adult trial in Canada into the United States (U.S.) following submission of the adolescent and adult trial protocol to the U.S.

这些决定是在IDMC审查了服用TSHA-102的患者的可用临床数据之后做出的。在向美国提交青少年和成人试验方案后，该公司还宣布将其正在加拿大进行的REVEAL 1/2期青少年和成人试验扩展到美国（美国）。

Food and Drug Administration (FDA)..

美国食品和药物管理局（FDA）。。

“We have been quite encouraged by the initial safety and efficacy data demonstrated to date with TSHA-102 and are pleased that we are cleared to dose the second patient in our REVEAL Phase 1/2 pediatric trial, and importantly, that the IDMC approved our request to proceed to dose escalation in our REVEAL Phase 1/2 adolescent and adult trial earlier than planned.

“我们对TSHA-102迄今为止所显示的初步安全性和有效性数据感到鼓舞，并且很高兴我们被允许在REVEAL 1/2期儿科试验中给第二名患者服用药物，重要的是，IDMC批准了我们的要求，以便在REVEAL 1/2期青少年和成人试验中比计划更早地进行剂量递增。

Advancing to the high dose cohort accelerates our ability to further inform our clinical development and regulatory plan for Part B of the study by at least a quarter,” said Sean P. Nolan, Chairman and Chief Executive Officer of Taysha. “Additionally, we believe expanding our ongoing REVEAL adolescent and adult trial in Canada into the U.S.

Taysha董事长兼首席执行官肖恩·诺兰（Sean P.Nolan）表示：“推进高剂量队列研究，将我们进一步为研究B部分的临床开发和监管计划提供信息的能力提高了至少四分之一。”。“此外，我们认为将加拿大正在进行的REVEAL青少年和成人试验扩展到美国。

will further support our goal to evaluate TSHA-102 across a broad range of ages and stages of patients with Rett syndrome. We are pleased with the progress we’ve made and remain focused on evaluating TSHA-102 as a potential treatment option for patients and families living with Rett syndrome.”.

将进一步支持我们在Rett综合征患者的广泛年龄和阶段评估TSHA-102的目标。我们对取得的进展感到高兴，并继续专注于评估TSHA-102作为Rett综合征患者和家庭的潜在治疗选择。”。

REVEAL Phase 1/2 adolescent and adult trial: a first-in-human, open-label, randomized, dose-escalation and dose-expansion study evaluating the safety and preliminary efficacy of TSHA-102 in adolescent and adult females aged 12 years and older with Rett syndrome due to MECP2 loss-of-function mutation.

REVEAL 1/2期青少年和成人试验：首次在人体内进行开放标签，随机，剂量递增和剂量扩展研究，评估TSHA-102在12岁及以上患有Rett综合征的青少年和成年女性中的安全性和初步疗效。MECP2功能丧失突变。

The trial is taking place in Canada and the U.S. TSHA-102 is administered as a single lumbar intrathecal injection. Dose escalation will evaluate two dose levels of TSHA-102 sequentially. The maximum tolerated dose (MTD) or maximum administered dose (MAD) established in Part A will then be administered during dose expansion in Part B of the study..

该试验正在加拿大进行，美国TSHA-102作为单次腰椎鞘内注射给药。剂量递增将依次评估TSHA-102的两个剂量水平。然后将在研究B部分的剂量扩展期间施用A部分中确定的最大耐受剂量（MTD）或最大给药剂量（MAD）。。

Dosing in cohort one (low dose, n=2) is now considered complete.

现在认为队列1（低剂量，n=2）的剂量已完成。

Update on available clinical data from completed cohort one of 5.7x1014 total vg expected in the first quarter of 2024.

2024年第一季度预计总vg为5.7x1014的完整队列之一的可用临床数据更新。

Dosing of the first patient in cohort two (high dose, n=3) of 1x1015 total vg expected in the second quarter of 2024.

预计2024年第二季度，第二组（高剂量，n=3）中第一名患者的总vg为1x1015。

Initial safety and efficacy data from cohort two expected in the second half of 2024.

队列二的初始安全性和有效性数据预计将于2024年下半年发布。

REVEAL Phase 1/2 pediatric trial: a first-in-human, open-label, randomized, dose-escalation and dose-expansion study evaluating the safety and preliminary efficacy of TSHA-102 in pediatric females with Rett syndrome due to MECP2 loss-of-function mutation. The trial is taking place in the U.S. and cleared in the U.K.

REVEAL 1/2期儿科试验：首次在人体内，开放标签，随机，剂量递增和剂量扩展研究，评估TSHA-102在由于MECP2功能丧失突变而患有Rett综合征的儿科女性中的安全性和初步疗效。审判正在美国进行，并在英国获得批准。

TSHA-102 is administered as a single lumbar intrathecal injection. Part A of the study will focus on determining MAD and MTD in patients aged 5-8 years old. Part B is the dose expansion phase and will evaluate TSHA-102 at the MAD or MTD in two age cohorts (5-8 years and 3-5 years)..

TSHA-102作为单次腰椎鞘内注射给药。该研究的A部分将重点确定5-8岁患者的MAD和MTD。B部分是剂量扩展阶段，将在两个年龄组（5-8岁和3-5岁）的MAD或MTD中评估TSHA-102。。

Dosing of the second patient in cohort one (low dose, n=3) of 5.7x1014 total vg expected in the first quarter of 2024.

预计2024年第一季度，队列一（低剂量，n=3）中第二名患者的总vg为5.7x1014。

Initial safety and efficacy data for cohort one expected in mid-2024.

队列一的初始安全性和有效性数据预计在2024年年中。

Initial safety and efficacy data from cohort two (high dose, n=3) of 1x1015 total vg expected in the second half of 2024.

预计2024年下半年，来自队列二（高剂量，n=3）的1x1015总vg的初始安全性和有效性数据。

About TSHA-102

关于TSHA-102

TSHA-102 is a self-complementary intrathecally delivered AAV9 investigational gene transfer therapy in clinical evaluation for Rett syndrome. 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是一种自我补充的鞘内注射AAV9研究性基因转移疗法，用于Rett综合征的临床评估。TSHA-102利用了一种新型的miRNA响应性自动调节元件（miRARE）技术，该技术旨在逐个细胞介导中枢神经系统中MECP2的水平，而没有过表达的风险。

TSHA-102 has received Fast Track designation and Orphan Drug and Rare Pediatric Disease designations from the FDA and has been granted Orphan Drug designation from the European Commission..

TSHA-102已获得FDA的快速通道指定、孤儿药和罕见儿科疾病指定，并已获得欧盟委员会的孤儿药指定。。

About Rett Syndrome

关于Rett综合征

Rett syndrome is a rare neurodevelopmental disorder caused by mutations in the X-linked MECP2 gene, which is a gene that’s essential for neuronal and synaptic function in the brain. The disorder is characterized by intellectual disabilities, loss of communication, seizures, slowing and/or regression of development, motor and respiratory impairment, and shortened life expectancy.

Rett综合征是一种罕见的神经发育障碍，由X连锁MECP2基因突变引起，该基因对大脑的神经元和突触功能至关重要。该疾病的特征是智力残疾，交流丧失，癫痫发作，发育减慢和/或消退，运动和呼吸障碍以及预期寿命缩短。

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..

Rett综合征主要发生在女性中，是严重智力残疾的最常见遗传原因之一。目前，还没有批准的疾病缓解疗法来治疗疾病的遗传根源。据估计，在美国，欧盟和英国，由致病性/可能致病性MECP2突变引起的Rett综合征会影响15000至20000名患者。。

About Taysha Gene Therapies

关于Taysha基因疗法

Taysha 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.

Taysha Gene Therapes（纳斯达克：TSHA）是一家临床阶段生物技术公司，专注于推进基于腺相关病毒（AAV）的基因疗法，用于治疗中枢神经系统的严重单基因疾病。它的主要临床项目TSHA-102正在针对Rett综合征进行开发，Rett综合征是一种罕见的神经发育障碍，没有经过批准的疾病缓解疗法来解决该疾病的遗传根源。

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.

Taysha专注于开发变革性药物，旨在解决严重未满足的医疗需求，并显着改善患者及其护理人员的生活。该公司的管理团队在基因治疗开发和商业化方面拥有丰富的经验。Taysha利用这一经验，其制造过程以及临床和商业证明的AAV9衣壳，努力将治疗从台式快速转化为床边。

For more information, please visit www.tayshagtx.com..

有关更多信息，请访问 www.tayshagtx.com。。

Forward-Looking Statements

前瞻性声明

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.

本新闻稿包含1995年《私人证券诉讼改革法案》所指的前瞻性声明。诸如“预期”、“相信”、“期望”、“打算”、“项目”、“计划”和“未来”等词语或类似表达旨在识别前瞻性陈述。

Forward-looking statements include statements concerning the potential of TSHA-102, including the reproducibility and durability of any favorable results initially seen in our first patient dosed in the REVEAL trial and the timing of dosing patients in clinical trials and availability of data from clinical trials, the potential of our product candidates to positively impact quality of life and alter the course of disease in the patients we seek to treat, our research, development and regulatory plans for our product candidates, the potential to accelerate the regulatory pathway for TSHA-102 and the potential benefits of Fast Track, Orphan Drug and Rare Pediatric Disease designations for TSHA-102.

前瞻性陈述包括有关TSHA-102潜力的陈述，包括在REVEAL试验中首次给药的患者中最初看到的任何有利结果的可重复性和持久性，以及在临床试验中给药患者的时间以及临床试验数据的可用性，我们的候选产品对我们寻求治疗的患者的生活质量产生积极影响并改变疾病进程的潜力，我们对候选产品的研究，开发和监管计划，加速TSHA-102监管途径的潜力以及TSHA-102快速通道，孤儿药和罕见儿科疾病指定的潜在益处。

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.

前瞻性陈述基于管理层当前的预期，并受到各种风险和不确定性的影响，这些风险和不确定性可能导致实际结果与此类前瞻性陈述所表达或暗示的结果存在重大不利差异。因此，这些前瞻性声明不构成对未来业绩的保证，请注意不要过度依赖这些前瞻性声明。

Risks regarding our business are described in detail in our Securities and Exchange Commission (“SEC”) filings, including in our Annual Report on Form 10-K for the full-year ended December 31, 2022, and our Quarterly Report on Form 10-Q for the quarter ended September 30, 2023, both of which are available on the SEC’s website at www.sec.gov.

我们的证券交易委员会（“SEC”）文件中详细描述了我们业务的风险，包括截至2022年12月31日的全年10-K表年度报告和截至2023年9月30日的季度10-Q表季度报告，均可在SEC网站www.SEC.gov上查阅。

A.

答：。

Company Contact:

公司联系人：

Hayleigh Collins

Hayleigh Collins

Director, Head of Corporate Communications, and Investor Relations

董事、企业传播和投资者关系主管

Taysha Gene Therapies, Inc.

Taysha基因治疗公司。

hcollins@tayshagtx.com

hcollins@tayshagtx.com

Media Contact:

媒体联系人：

Carolyn Hawley

Carolyn Hawley

Inizio Evoke

启动Evoke

Carolyn.hawley@inizioevoke.com

Carolyn.hawley@inizioevoke.com