Clinical Report: Gene Therapy Reaches XLRS Milestone

Overview

Atsena Therapeutics has reported interim six-month results from Part B of the LIGHTHOUSE trial evaluating ATSN-201, a gene therapy for X-linked retinoschisis (XLRS). The findings indicate structural and functional improvements in treated adults, alongside a favorable safety profile.

Background

X-linked retinoschisis (XLRS) is an inherited retinal disease caused by mutations in the RS1 gene, primarily affecting males, leading to impaired visual acuity and progressive vision loss. With approximately 30,000 males in the US and EU affected and no approved treatments available, advancements in gene therapy represent a significant development in managing this condition. The LIGHTHOUSE trial aims to evaluate the efficacy and safety of ATSN-201 in both adult and pediatric populations.

Data Highlights

Key Findings

• Foveal schisis closure was confirmed in four of six treated adults in Cohort 4.
• No serious adverse events were reported across Part B cohorts.
• Microperimetry responses in Part B mirrored those observed in Part A.
• Pediatric patients aged 8–12 showed no serious adverse events.
• Enrollment is underway for Part C, targeting 76 patients for the pivotal Phase 3 trial.

Clinical Implications

The positive interim results from the LIGHTHOUSE trial suggest that ATSN-201 may provide a new therapeutic option for patients with XLRS. The favorable safety profile observed in both adult and pediatric cohorts is critical for future treatment considerations.

Conclusion

The LIGHTHOUSE trial marks a significant milestone in the development of gene therapy for XLRS, with promising results that may pave the way for future treatment options.

Related Resources & Content

1. New Retinal Physician, 2024 -- LIGHTHOUSE Trial for XLRS Gene Therapy Initiates Dosing of Second Cohort
2. Retinal Physician, 2025 -- Atsena Reports LIGHTHOUSE data at ARVO
3. Retinal Physician, 2025 -- Atsena Completes Adult Dosing in LIGHTHOUSE Trial
4. AAO Clinical Assessment of Patients with Inherited Retinal Degenerations Guideline Summary - Guideline Central
5. Retinal AAV8-RS1 Gene Therapy for X-Linked Retinoschisis: Initial Findings from a Phase I/IIa Trial by Intravitreal Delivery - PMC
6. Retinal Physician — Atsena Reports Gene Therapy Durability Data
7. AAO Clinical Assessment of Patients with Inherited Retinal Degenerations Guideline Summary - Guideline Central
8. Retinal AAV8-RS1 Gene Therapy for X-Linked Retinoschisis: Initial Findings from a Phase I/IIa Trial by Intravitreal Delivery - PMC
9. Atsena Presents Positive Clinical Data from Its XLRS and