Taysha Gene Therapies

Taysha Gene Therapies, founded by R.A. Session II in 2019, was recently featured at the Biotechnology Club semesterly 'Biotech & Brews: Science and Entrepreneurship' event in the spring of 2021. We had the pleasure of sitting down virtually with R.A. Session II, Founder and CEO, and Steven Gray, Chief Scientific Advisor and Associate Professor at UT Southwestern, to talk more about this fast growing UTSW spinout. Taysha's mission is to utilize gene therapies to not only treat monogenic central nervous system (CNS) disease, but to eradicate it through the development of curative medicines. Gene therapies have become a revolutionary approach in targeting diseases at the genomic level, where human genes can be engineered to silent the expression of unwanted genes, such as oncogenes. Taysha has had an incredible start during the midst of a pandemic last year, raising $125 million in Series A and Series B funding, followed by a $157 million IPO in less than six months. (1)

R.A. Session II was also featured in the Dallas Innovates' Future 50 in DFW 2021 annual edition for his work as CEO and founder of Taysha Gene Therapies. In 2021, the company plans to move into offices at the new Dallas biohub, Pegasus Park. Additionally, the company is breaking ground on their 187,000-square-foot manufacturing facility located in Durham, NC which is expected to be fully commissioned by 2023. (2) 

The program was invented in the lab of Dr. Steven Gray, where his lab has been focused in AAV vector development to develop vectors tailored to clinical and research applications that involve the nervous system. This partnership with the world-class UT Southwestern Gene Therapy Program has quickly gone from a preclinical- to clinical-stage company in less than two years, with their pipeline continually growing. (3) Building off of this, Taysha's program has rapidly grown in developing a deep pipeline encompassing a variety of treatments for multiple CNS diseases, from rare indications to large patient populations. Their gene replacement therapy (GRT) indications include, but are not limited to, giant axonal neuropathy (GAN), GM2 gangliosidosis, GM2 AB variant and CLN1 disease. The program also includes microRNA (miRNA) and short hairpin RNA (shRNA) treatment techniques for a vast array of additional indications. (4) Many of the gene therapies in Taysha's portfolio have also achieved Orphan Drug Designation from the FDA, which is granted to treatment options that affects less than 200,000 persons in the US. (5) The company also anticipates having four open Investigational New Drug applications in 2021. (2)

Most recently, Taysha has acquired exclusive worldwide rights to clinical-stage AAV9 gene therapy program, TSHA-120, which is utilized for the treatment of GAN. This clinical trial was historic, being the first intrathecally dosed gene therapy program and showcased human proof-of-concept data that illustrated clear arrest of disease progression in patients with GAN. (6)


  1. https://dallasinnovates.com/success-in-the-genes-launching-in-a-pandemic-didnt-hurt-this-fast-growth-dallas-biotech-company/

  2. https://www.businesswire.com/news/home/20201217005961/en/Taysha-Gene-Therapies-Announces-New-cGMP-Gene-Therapy-Manufacturing-Facility

  3. https://tayshagtx.com/pipeline/

  4. https://tayshagtx.com/approach/

  5. https://www.fda.gov/industry/developing-products-rare-diseases-conditions

  6. https://ir.tayshagtx.com/node/7106/pdf