Eyeing phase 3, Atsena raises $55M financing for blindness gene therapy

Dry eye
(YaroslavKryuchka/Getty Images)

University of Florida (UF) spinout Atsena Therapeutics has closed a $55 million financing that will help take its gene therapy for a common cause of blindness in children into pivotal trials.

The gene therapy is already in a phase 1/2 trial for Leber congenital amaurosis (LCA)—a disease that progressively destroys the retina—in patients with a mutation in the GUCY2D gene. Atsena acquired the candidate from Sanofi earlier this year, which in turn licensed it from UF.

The Durham, North Carolina-based biotech is hoping to follow in the footsteps of Spark Therapeutics (now part of Roche), whose Luxturna became the first directly administered gene therapy to be approved in the U.S. in 2017.

Luxturna has been approved for LCA caused by mutations in the RPE65 gene, as well as another inherited retinal disease called retinitis pigmentosa.

Atsena’s GUCY2D therapy—known as SAR439483—emerged from the lab of Atsena co-founder and Chief Scientific Officer Shannon Boye, Ph.D., and co-founder and Chief Technology Officer Sanford Boye, both working at UF’s College of Medicine.

The therapy is being administered by subretinal injection to one eye of each patient in the phase 1/2 study so that the untreated eye can serve as a control, with a year of follow-up after dosing. Preliminary results are due in the first half of next year.

The series A money will be used to complete the phase 1/2 trial, scale up manufacturing of the gene therapy in preparation for phase 3 testing and boost Atsena’s headcount in North Carolina’s Research Triangle and in Boston.

It comes after Atsena closed a series 1 funding amounting to just over $8 million in April, which was led by founding investors Hatteras Venture Partners and the Foundation Fighting Blindness (FFB).

It will also help bring forward two preclinical candidates, including a therapy for MYO7A-associated Usher syndrome, which causes vision and hearing impairment, and fund refinements to Atsena’s adeno-associated virus (AAV) capsid delivery platform.

According to CEO Pat Ritschel, Atsena’s platform promises to “overcome the unique hurdles of inherited retinal diseases to prevent or reverse blindness.”

The biotech’s approach relies on the use of two AAV vectors delivered in tandem, each carrying part of the gene construct that is to be delivered by the therapy. That means it can be used to deliver genes that are too big to be contained within single vectors.

Collectively, LCA is the most common form of blindness in children, with two to three cases per 100,000 people. GUCY2D-LCA1 is one of the most common forms of the disease, accounting for approximately 20% of all LCA patients.

Hatteras and FFB also participated in the series A, which was led by Sofinnova Investments with participation from additional new investors Abingworth and Lightstone Ventures. Existing backers Osage University Partners, UF and the Manning Family Foundation also took part.

“We believe Atsena’s foundation in ocular gene therapy and potentially game-changing novel AAV vectors position the company to become a partner of choice,” said Sarah Bhagat, Ph.D., partner at Sofinnova, who is joining the biotech’s board along with Abingworth’s Jackie Grant, Ph.D., and Lightstone’s Jason Lettmann.