• ATSN-101 continues to demonstrate clinically meaningful improvements in vision at the highest dose and is well-tolerated 12 months post-treatment
  • Data accepted for presentation at 47th Annual Macula Society Meeting

DURHAM, NC, USA I December 04, 2023 I Atsena Therapeutics, a clinical-stage gene therapy company focused on bringing the life-changing power of genetic medicine to reverse or prevent blindness, today announced positive 12-month safety and efficacy data from the ongoing Phase I/II trial of ATSN-101, the company’s investigational gene therapy for the treatment of GUCY2D-associated Leber congenital amaurosis (LCA1). At 12 months post-treatment, ATSN-101 has conferred clinically meaningful improvements in vision at the highest dose with no serious treatment-emergent adverse events.

“We continue to be encouraged by the data emerging from our Phase I/II trial of ATSN-101 in patients with GUCY2D-associated LCA1,” said Kenji Fujita, MD, Chief Medical Officer of Atsena Therapeutics. “The durability of clinically meaningful visual improvements in the absence of serious treatment-related adverse events at the 12-month mark underscore the safety, tolerability, and efficacy of our subretinal gene therapy. We believe the 12-month findings provide solid proof of concept that ATSN-101 will exceed the requirements set by the U.S. Food and Drug Administration for ultimate approval. We are exploring partnering and out-licensing options to advance ATSN-101 into a pivotal trial.”

In the Phase I/II trial, 15 patients ages 12 to 76 received unilateral subretinal injections of ATSN-101. Three adult cohorts (N=3 each) were treated with three ascending doses. Subsequently, one adult and one pediatric cohort (N=3 each) were treated at the high dose. In total, 9 patients received the high dose.

At 12 months, there were no serious treatment-emergent adverse events. Ocular inflammation was mild and reversible with steroid treatment. For high-dose patients, the mean (SE) change from baseline in dark-adapted full-field stimulus testing (FST) (white stimulus) was greater in treated eyes compared with untreated eyes at all six follow-up visits, and some patients exhibited over 10,000-fold improvements in retinal sensitivity. Of the six high-dose patients who were tested with multi-luminance mobility testing (MLMT), three improved by ≥2 levels compared to baseline (when available) or to the untreated eye, and all three demonstrated a maximum score of 6 in the treated eye. At 12 months, patients receiving the high-dose demonstrated a statistically significant improvement in best-corrected visual acuity (BCVA).

“The noteworthy improvements in key visual parameters demonstrate the potential of ATSN-101 to make a meaningful impact on the lives of patients affected by GUCY2D-associated LCA1,” said Paul Yang, MD, PhD, Associate Professor of Ophthalmology at OHSU School of Medicine. “As LCA1 causes early and severe vision impairment or blindness and there are no approved treatments, ATSN-101 has the potential to fill a significant unmet need within the LCA community.”

The 12-month data have been accepted for presentation at the 47th Annual Macula Society Meeting, which will be held February 7-10, 2024, in Palm Springs, CA.

The U.S. Food and Drug Administration (FDA) recently granted Regenerative Medicine Advanced Therapy (RMAT) designation to ATSN-101. Atsena has also received orphan drug designation from the FDA for ATSN-101 for the treatment of LCA1.

About GUCY2D-associated Leber congenital amaurosis (LCA1)
LCA1 is a monogenic eye disease that disrupts the function of the retina. It is caused by mutations in the GUCY2D gene and results in early and severe vision impairment or blindness. GUCY2D-LCA1 is one of the most common forms of LCA, affecting roughly 20 percent of patients who live with this group of inherited retinal diseases. There are currently no approved treatments for LCA1.

About Atsena Therapeutics
Atsena Therapeutics is a clinical-stage gene therapy company developing novel treatments for inherited forms of blindness. The company has two clinical-stage programs, ATSN-201 for X-linked retinoschisis (XLRS) and ATSN-101 for GUCY2D-associated Leber congenital amaurosis (LCA1). ATSN-201, which leverages the company’s novel spreading capsid AAV.SPR, is being evaluated in XLRS patients in a Phase I/II clinical trial known as the LIGHTHOUSE study. The company’s additional proprietary asset is ATSN-301, a dual AAV vector-based gene therapy to prevent blindness from MYO7A-associated Usher syndrome (USH1B). Interim safety and efficacy data from the company’s ongoing Phase I/II clinical trial in patients with LCA1 have demonstrated ATSN-101 is well tolerated and clinically meaningful improvements in vision were observed 12 months post-treatment. Founded by ocular gene therapy pioneers Dr. Shannon Boye and Sanford Boye of the University of Florida, Atsena is based in North Carolina’s Research Triangle, an environment rich in gene therapy expertise. For more information, please visit atsenatx.com.

SOURCE: Atsena Therapeutics