SLC13A5 Gene Therapy Development Update

TESS Research Foundation originally anticipated clinical trials for a gene therapy targeting SLC13A5 Epilepsy (SLC13A5 Deficiency) to launch by the end of 2022. It’s 2024, so, why haven’t these trials started yet?

We know our community eagerly awaits any updates on gene therapy clinical trials and we hope this blog post helps explain where we are in the gene therapy clinical trial process.

First we want to assure our community that our science remains strong and the gene therapy program continues to move forward. Our focus remains on delivering the safest and most effective gene therapy.

Drug development takes time and money – often billions of dollars over 10-plus years of work – to take a single drug from the laboratory into a human (what is sometimes referred to as “bench to bedside.”). Due to high costs and lengthy time commitments, the majority of drug companies tend to focus on drug development that has the potential to treat larger patient populations instead of smaller rare disease patient populations.

There are a handful of drug companies that focus on rare disease, including Taysha Gene Therapies Inc. In January 2021, Taysha received an Orphan Drug Designation for TSHA-105, the gene therapy drug developed by Dr. Rachel Bailey and her team at UT Southwestern, for the treatment of epilepsy caused by SLC13A5 Deficiency. This designation took us one step closer to getting a gene therapy into human clinical trials. In 2022, the biotech industry suffered a financial downturn and Taysha’s plan for TSHA-105 was put on hold. It is important to note that Taysha’s support of SLC13A5 gene therapy development is delayed due to the funding, not the science. This is where TESS has stepped in to keep progress going.

Currently, we are partnering with our teams at Stanford and UT Southwestern to continue working to make the safest and most effective drug possible and to work toward clinical trials. We are grateful to the families who have completed and continue to participate in our in-person and remote preclinical studies (Natural History Studies). The data being collected about SLC13A5 Epilepsy and our patient community is helping to inform our future clinical trial protocols – for any and all therapeutics for SLC13A5 Epilepsy – and is important as we seek Food and Drug Administration (FDA) approval.