Spark Therapeutics Inc (NASDAQ: ONCE) Luxturna, the first gene therapy in the U.S., has been approved by the Food and Drug Administration. The gene therapy is intended to treat a rare, inherited retinal disease that could possibly cause blindness. Unlike some other treatments that require multiple therapies and steady payments, the Luxturna treatment will require only one treatment.

The company announced on their press release that they will be offering “outcome-based rebates and an innovative contracting model that support patient access in the U.S. while aiming to reduce risk and financial burden for payers and treatment centers.”

Spark Therapeutics has teamed with Express Scripts on distribution and pharmacy services for Luxturna. Dr. Steve Miller, chief medical officer of Express Scripts, agrees that the treatment iis very expensive, but believes the company has put it at a fair price range. "The product is just phenomenally innovative, and we've been talking about gene therapy for over 20 years. We're now at the threshold of having gene therapy reaching patients." says Miller.

The gene therapy targets a gene mutation called RPE65, which causes deteriorating vision over time. The treatment is performed by using a healthy copy of a gene to make up for the deficiency that the gene mutation causes.

The one time, outcome-based payment program could be a model for future one time treatments.