The first gene therapy for an inherited disease in the U.S. is closer to reality than ever before.

Spark Therapeutics is only the second company to pursue an application to the U.S. Food and Drug Administration for such a treatment, but it’s likely to be the first to hit the market.

Speaking at EmTech MIT 2016 on Tuesday, Katherine High, Spark’s cofounder, confirmed that the company is on track to launch its first product next year. The gene therapy, known as SPK-RPE65, targets mutations in people’s eyes that often lead to blindness. Currently, there are no drugs available to treat these disorders, known as inherited retinal dystrophies.

Spark plans to complete its FDA application by early 2017. If approved next year, the therapy would become the first for an inherited disease to be given the green light in the U.S. Two such gene therapies, Strimvelis and Glybera, have already been approved in Europe.

Glybera’s maker, UniQure, initially sought FDA approval for its gene therapy, which treats a rare genetic disorder called lipoprotein lipase deficiency (LPLD). But the company dropped those plans in December 2015 after the FDA countered the application with a request to run additional clinical trials to prove the therapy’s effectiveness.

The gene therapy field has seen its share of clinical failures, including a patient death in 1999 due to complications of an experimental treatment. High says previous failures occurred in part because animal models didn’t adequately expose the potential glitches of gene therapy.  

“You have to solve a critical mass of problems before you can start therapeutic development in earnest,” she said.

Spark has arguably solved those problems with SPK-RPE65. This week, the company presented Phase III data at the American Academy of Ophthalmology’s annual meeting showing that 27 of 29 subjects who were virtually blind experienced an increase in vision function for more than a year following the procedure. No patients have had any serious adverse events associated with with the treatment, according to the company. High said the therapy is administered in a 45-minute surgical procedure under anesthesia, and a change in vision can be seen within 30 days.

High said in an interview Tuesday that the company has concluded the trial and doesn’t plan to conduct any additional testing before seeking FDA approval—a sign that Spark is confident about its FDA application.

Spark first began testing SPK-RPE65 in 2007, and since has joined a small cadre of companies that have advanced experimental gene therapies past initial safety trials and into late-stage testing. Meanwhile, Spark is also working on a gene therapy for hemophilia, which is already showing promising results.