Atsena Therapeutics announced that the U.S. Food and Drug Administration (FDA) has granted Rare Pediatric Disease designation (RPD) for ATSN-201 for the treatment of X-linked retinoschisis (XLRS). ATSN-201, a best-in-class gene therapy product candidate, leverages AAV.SPR, the company’s novel spreading capsid, to achieve therapeutic levels of gene expression in photoreceptors of the central retina while avoiding the surgical risks of foveal detachment.
“We are pleased to receive the FDA’s Rare Pediatric Disease designation for ATSN-201, which also marks the second RPD designation granted to Atsena this year. Having both of our clinical-stage, ocular gene therapies receive this designation underscores the potential of our technology to address significant unmet needs for patients with inherited retinal diseases,” said Patrick Ritschel, CEO of Atsena Therapeutics. “We are committed to advancing ATSN-201 in clinical trials and offering hope to patients and families affected by XLRS.”
Currently, there are no approved treatments for XLRS, which is typically diagnosed in early childhood and primarily affects males. Approximately 30,000 males in the U.S. and EU are affected by this condition.
The safety and tolerability of ATSN-201 is currently being evaluated in the LIGHTHOUSE study, a phase 1/2, open-label, dose-escalation and dose-expansion clinical trial in male patients ages six and older with a clinical diagnosis of XLRS caused by mutations in the RS1 gene.
Enrollment for this study is ongoing. For more information, visit ClinicalTrials.gov (Identifier: NCT05878860).
The FDA grants Rare Pediatric Disease designation to therapeutics intended to treat serious or life-threatening rare diseases that primarily affect individuals under the age of 18. With this designation, ATSN-201 will be eligible to receive a priority review voucher (PRV) upon approval that could be used to advance another internal program or be sold to an outside company. The FDA’s PRV program greatly incentivizes companies like Atsena to invest in rare pediatric diseases.
About X-linked Retinoschisis (XLRS)
XLRS is a monogenic X-linked disease caused by mutations in the RS1 gene which encodes retinoschisin, a protein secreted primarily by photoreceptors. RS1 is localized to the extracellular surface of rods, cones, and bipolar cells. XLRS is characterized by schisis, or abnormal splitting of retinal layers, which causes impaired visual acuity that is not correctable with glasses and leads to progressive vision loss and ultimately blindness. XLRS primarily affects males and is typically diagnosed in early childhood. Approximately 30,000 males in the U.S. and EU have XLRS, for which there are currently no approved treatments.
About AAV.SPR
AAV.SPR, one of Atsena’s novel capsids, spreads laterally beyond the subretinal injection site to enable safe and efficient transduction of the central retina (where schisis cavities predominate in XLRS patient retinas) when injected into areas outside the macula. A preclinical study in non-human primates demonstrated that AAV.SPR promotes transgene expression well beyond subretinal injection bleb margins. This is in stark contrast to benchmark AAV vectors, which remain confined to the original bleb margins. At clinically relevant doses, AAV.SPR efficiently transduces foveal cones without the need for surgical detachment and does not cause inflammation. For more information about the preclinical study and how AAV.SPR works, visit https://atsenatx.com/our-approach/laterally-spreading-aav/.