Taysha raises $150M to support testing of gene therapy, TSHA-102
Phase 1/2 trial underway in adults in Canada, pediatric study possible in US
Taysha Gene Therapies, which is developing TSHA-102 as a potential Rett syndrome treatment, raised $150 million in a private placement funding round, with most of the money supporting clinical testing of this gene therapy.
TSHA-102 is being evaluated in the REVEAL Phase 1/2 clinical trial (NCT05606614) in up to 12 adult women with Rett, currently taking place at a site in Montreal, Canada. A U.S. trial of the gene therapy in children with Rett also is possible, with regulatory approval recently secured.
“Over the last 13 years, gene therapies have been or are being developed for a wide range of rare diseases,” Craig Gordon, MD, founder, CEO, and chief investment officer of GordonMD Global Investments, which participated in the funding round, said in a press release. “I am excited to help fund the development of such a therapy for the potential treatment of Rett Syndrome.”
Company work in giant axonal neuropathy, another genetic neurological condition, also will benefit from the funding.
Rett gene therapy showing early potential in clinical trial in adult patients
Rett mainly is caused by mutations in the MECP2 gene located in the X chromosome, which provides instructions to produce the MeCP2 protein. This protein regulates the activity of other genes and plays an important role in brain development and function.
TSHA-102 is designed to deliver a healthy copy of the MECP2 gene, using a modified and harmless adeno-associated virus containing a shorter but functional version of this gene.
The delivered sequence also contains a “switcher” that allows the gene to be expressed only in nerve cells. The gene therapy also uses a novel technology called miRARE, intended to prevent harmful overproduction of the MeCP2 protein, since healthy cells already produce sufficient amounts.
The therapy is delivered by a single intrathecal injection, directly into the spinal canal.
In preclinical studies in a mouse model of the disease, the therapy was found to be safe and to normalize MeCP2 levels in the brain. It also extended the animals’ survival.
REVEAL is evaluating the safety, tolerability, and efficacy of two dose levels of TSHA-102 in Rett patients, with a first woman dosed in June.
No serious treatment-related side effects were reported six weeks after the dosing, and preliminary data suggest benefits in her sleep, breathing, and motor skills. Particularly, the woman was able to sit unassisted for several minutes, and showed improvements in hand function, being able to hold objects or use her fingers to touch a screen.
An independent data monitoring committee — a group of experts who ensure safety of trial participants and data integrity — recommended the study’s continuation based on these findings, and dosing of a second trial patient is expected.