Jeffrey Marrazzo, CEO of gene therapy developer Spark Therapeutics, will step down as head of the company he co-founded almost nine years ago, steered to a historic Food and Drug Administration approval in 2017 and later led through a $4.3 billion buyout by Roche.
Marrazzo will depart on April 1, Spark said Wednesday. He will be succeeded by Ron Philip, a veteran of the company who oversaw the launch of Luxturna, Spark's first product and the first gene therapy for an inherited disease to be cleared in the U.S.
Spark's development from a startup spun out of the Children's Hospital of Philadelphia to a pioneering drugmaker paralleled the re-emergence of the gene therapy field, which over the past decade recovered from setbacks to become one of the fastest-growing segments of the biotech industry.
"We were trying to do a lot of things that people thought were not possible," Marrazzo said in an interview. "We had a hospital as a venture capitalist" and "gene therapy was closer to science fiction than fact and we were trying to build a biotech company in Philadelphia."
Spark's success set a precedent that others later followed, helping to establish Philadelphia and its cluster of research hospitals as a hub for gene therapy research. There are now more than 45 cell and gene therapy biotechs based in the city, according to a farewell letter Marrazzo wrote to Spark employees.
Luxturna, which treats a form of childhood blindness and can improve sight in people with the condition, gave gene therapy developers a roadmap for how to meet the FDA's approval requirements, manufacture their products at commercial scale and sell them in the U.S.
"It was the first gene therapy in the U.S. to come out," Philip said in an interview. "There was no playbook to follow. We had to figure out things from scratch."
Another gene therapy, called Zolgensma and sold by Novartis, was approved by the FDA in 2019. Genetic treatments for hemophilia, the blood disease beta thalassemia and a rare brain condition could soon follow this year and next, and the FDA has said it expects to be reviewing many more in the years ahead.
Despite that progress, a number of companies in the field have recently hit setbacks, particularly around safety, that have renewed questions about gene therapy's potential in some diseases.
"I think the process of developing gene therapy is not a fast win," Philip said. "Some of the setbacks are learning opportunities that we can use to tweak, to make better and to improve the overall science behind the platform."
Both Marrazzo and Philip stayed with Spark even after Roche bought the company in 2019. The acquisition, which for a time attracted the attention of U.S. antitrust regulators, established the Swiss pharma's presence in gene therapy, a foothold it has since expanded through further dealmaking.
Unlike some other large drugmakers that bought into the field, Roche has kept Spark as an integrated subsidiary, based in Philadelphia. In December, the company announced it will invest more than half a billion dollars to build a new development and manufacturing center in the city.
"My goal was to stay at Spark long enough following the acquisition by Roche to really help the transition," Marrazzo said. "A lot of that positioning was about some of the investments that we announced in December, it was about the progress in our programs [and] also about getting Ron in position to take it from here."
"They're very comfortable with this model," Philip said. "They're long investors in the future of science and they have a lot of patience in terms of making those investments."
Philip, currently Spark's chief operating officer, will take over management of a company that employs more than 800 people and has plans to double that number over the next five years.
Behind Luxturna, Spark has advanced to late-stage testing gene therapies for hemophilia A and B and has a clinical candidate in earlier study for Pompe disease, a type of lysosomal storage disorder. (Pfizer owns rights to the hemophilia B candidate.)
Meanwhile, Marrazzo aims to help other founders and companies emulate Spark's growth. He said he doesn't have plans to take another CEO job at the moment, but hopes to share his experience "across multiple fields, including biotech and other areas of healthcare, philanthropy and public policy."