Spark Therapeutics, Inc. focuses on the development of gene therapy products for patients suffering from debilitating genetic diseases. Its products include voretigene neparvovec, which is in Phase III clinical trial for the treatment of genetic blinding conditions called inherited retinal diseases caused by non sex-linked, autosomal recessive, or biallelic mutations in the RPE65 gene; and SPK-CHM that is in Phase I/II clinical trial for the treatment of choroideremia. The company's products also comprise SPK-7001 that is in Phase 1/2 trial for choroideremia; SPK-9001, which is in Phase 1/2 trial for hemophilia B; and SPK-8011 that is in Phase 1/2 trial hemophilia A. In addition, its product candidates and development programs include SPK-FVIII program to treat hemophilia A; SPK-TPP1 program for the treatment of a form of Batten disease and Huntington's disease; RhoNova for the treatment of rhodopsin-linked autosomal dominant retinitis pigmentosa; and SPK-LHON for treating Leber hereditary optic neuropathy, as well as preclinical programs in development for the treatment of rare genetic blinding conditions, hematologic disorders, and other neurodegenerative diseases. The company has collaboration agreement with Pfizer, Inc. for the development and commercialization of SPK-FIX product candidates in its gene therapy program for the treatment of hemophilia B. Spark Therapeutics, Inc. was founded in 2013 and is headquartered in Philadelphia, Pennsylvania.