Spark Therapeutics announced that Ron Philip, Spark's chief operating officer, will succeed co-founder Jeffrey D. Marrazzo as chief executive officer. Jeff, who co-founded the company in 2013, will step down on April 1. As co-founder and CEO of Spark, Jeff created a fully integrated, commercial gene therapy company that successfully delivered to patients the world's first gene therapy approved by both the FDA and EMA, while also discovering and developing potential treatments and cures for inherited retinal disease and rare bleeding and neuromuscular disorders.