ARVO 2023: Atsena Therapeutics announces 6-month data from ongoing Phase I/II clinical trial of ATSN-101

(Image Credit: Adobe Stock)

Atsena Therapeutics announced positive 6-month safety and efficacy data from the ongoing Phase I/II clinical trial of ATSN-101, the company’s investigational gene therapy for the treatment of GUCY2D-associated Leber congenital amaurosis (LCA1).

The data were presented by Christine Nichols Kay, MD, clinical ophthalmology Advisor for Atsena, at the Association for Research in Vision and Ophthalmology (ARVO) 2023 Annual Meeting.

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.

Kenji Fujita, MD, chief medical officer of Atsena Therapeutics, pointed out the company was encouraged by the clinically meaningful improvements in vision ATSN-101 has demonstrated at the highest dose 6 months post treatment, as well as the favorable safety profile of our subretinal gene therapy.

“The latest data reinforce our confidence in the potential of ATSN-101 to improve vision in patients with GUCY2D-associated LCA1, which results in early and severe vision impairment or blindness and lacks an approved treatment,” Fujita said in a statement. “We look forward to reporting 12-month data later this year and are exploring options to advance ATSN-101 into a pivotal trial.”

According to the company, in the Phase I/II trial, 15 patients, including three pediatric patients, received ATSN-101 via subretinal delivery. Three adult cohorts (N=3 each) were treated with three ascending doses. Six additional patients received the high dose in a dose expansion phase. Among patients who received the high-dose treatment (N=9), the mean (SE) change from baseline in retinal sensitivity by dark-adapted full-field stimulus testing (FST) was significantly greater in treated eyes compared with untreated eyes at Day 28 and all subsequent follow-up visits.

The company noted two high-dose patients demonstrated best corrected visual acuity (BCVA) improvement greater than 0.3 logMAR, and no treated eyes had a decrease in BCVA. Of the five high-dose patients who were tested with the MLMT mobility test, four patients demonstrated

either a maximum MLMT score of 6 or a ≥2 level improvement, compared to baseline when available or to the untreated fellow eye, at one or more post-treatment visits.

To date, no drug-related serious adverse events have been reported and ocular inflammation has been infrequent, minimal, and reversible with steroid treatment.