Gene Therapy Improved Giant Axonal Neuropathy

In a phase 1/2 clinical trial (NCT02362438), individuals with giant axonal neuropathy (GAN) treated with gene therapy (TSHA-120; Taysha Gene Therapies, Dallas, TX) recovered sensory nerve amplitudes (SNAPs). Treated individuals also had clinical improvement. 

In the natural history of GAN, a rare genetic disorder, SNAPs are lost with disease progression. In contrast, the participants treated with this gene therapy had durable neurophysiologic improvements in SNAPs. Sensory function was also maintained. 

The gene therapy is carried on the adeno-associated viral vector 9 (AAV9), and nerve biopsies from participants (n=11) showed the presence of the gene therapy in regenerative nerve fibers. 

“We are excited to announce important progress in GAN including stabilization and improvement of sensory nerve function in patients with GAN following treatment with TSHA-120,” said RA Session II, president, founder, and CEO, Taysha. “In addition, we now have positive comparability data demonstrating that our commercial grade and clinical trial material are comparable across all key quality attributes. Importantly, we believe positive feedback received from the MHRA, in conjunction with robust comparability data for TSHA-120 and comprehensive clinical data generated to date, further support our ongoing regulatory engagement.”