Atsena secures $150M Series C to advance ocular gene therapies

Atsena Therapeutics announced the successful close of an oversubscribed $150 million Series C financing, the proceeds of which will be used to advance its lead gene therapy program for the treatment of X-linked retinoschisis (XLRS), a genetic condition that leads to blindness.

XLRS is a monogenic X-linked disease caused by mutations in the RS1 gene which encodes retinoschisin, a protein secreted primarily by photoreceptors. It 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.

The financing was led by Bain Capital’s Life Sciences team, with participation from an additional new investor, Wellington Management. Existing investors, including Lightstone Ventures, Sofinnova Investments, Abingworth, Foundation Fighting Blindness, Hatteras Venture Partners, Osage University Partners, and the Manning Family Foundation, also participated in the round.

Proceeds from the financing will be used to advance ATSN-201, a best-in-class gene therapy product candidate that 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. AAV.SPR 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.

The therapy has been granted fast track, rare pediatric disease and orphan drug designations. Updated data from the ongoing LIGHTHOUSE phase 1/2 clinical trial evaluating ATSN-201 is anticipated later this year.

The Series C proceeds will also support Atsena’s preclinical pipeline of first-in-class therapies and expand the use of the company’s novel spreading AAV.SPR capsid.