We Are Spark

Chris Stevens
Chief Patient Supply Officer

As Spark Therapeutics’ Chief Patient Supply Officer, Chris Stevens leads a team of dedicated professionals working together in manufacturing and technical operations, supply chain, quality and compliance to deliver transformational therapies for patients globally. Chris is also responsible for capital investments, engineering, EHS, real estate and facilities management across the enterprise.

Since joining Spark in 2017, Chris has effectively led teams in several key areas, initially serving as Head of Manufacturing where he led the development of Spark’s manufacturing network through the filing and launch of Luxturna, the first approved gene therapy for genetic disease in both the US and EU. Later, Chris held the role of Asset General Manager, Hemophilia A where he had end to end responsibility for Spark’s Hem A program before being promoted to Head of Product Strategy where he led the team responsible for all programs in Spark’s portfolio. Chris was appointed Chief Patient Supply Officer for Spark in the fall of 2022.

With more than 25 years’ end to end leadership experience in gene therapy, biotech, pharmaceutical and consumer products industries, Chris is an industry veteran with deep expertise in designing and operating supply chains in complex regulatory environments, manufacturing science and technology, technology transfer, quality, compliance, product strategy and P&L management.

Prior to Spark, Chris led teams at GlaxoSmithKline (GSK) focused on strategy, operations and planning, as well as GMP clinical manufacturing operations including process transfer and cell banking. Earlier in his career he held roles of increasing responsibility at Bristol-Myers Squibb (BMS) in process engineering, manufacturing and supply chain in Massachusetts, Indiana and Puerto Rico.

Beyond his role with Spark, Chris currently serves as President of the Board at A Haven – a non-profit family grief center in Chester County, Pennsylvania. He received his M.S. in Industrial Management from the University of Southern Indiana and a B.S. in Chemical Engineering from Purdue University.

Sylke Poehling, Ph.D. 
Chief Executive Officer

Sylke Poehling is an accomplished biotech and pharma executive with over 25 years of experience. As Chief Executive Officer of Spark Therapeutics, Sylke leads a talented team dedicated to Spark’s mission: to unlock the power of gene therapy to accelerate healthcare transformation. Sylke’s leadership at Spark is informed by her extensive background in the biotech industry, particularly her deep expertise in gene therapy and drug discovery.

In addition to her role at Spark, Sylke continues to serve as Senior Vice President and Global Head of Therapeutic Modalities for Roche, where she is accountable for research and drug discovery activities across six therapeutics areas, leading over 700 scientists at two R&D innovation centers. She is a key strategic member of the executive leadership team of Roche Pharma Research & Early Development (pRED) and has served as co-chair of Roche’s Early Stage Portfolio Committee. Sylke provides guidance on a portfolio of over 120 research and early development projects and has been instrumental in driving the company’s innovation strategy, which focuses on the development of transformative medicines.

Prior to her role as CEO of Spark and SVP and Global Head of Therapeutic Modalities at Roche, Sylke held various leadership positions at Roche. Sylke is a Professor of Practice at the ETH Zurich in the Department of Biosystems Science and Engineering. She also serves as a mentor and sponsor for talent within Roche, with a particular focus on advancing women in STEM.

Sylke’s dual roles at Spark and Roche highlight her commitment to pushing the boundaries of science and improving the lives of patients around the world. Sylke can be found on LinkedIn.

Michael Retterath
Chief Business Officer

Michael Retterath serves as Chief Business Officer at Spark Therapeutics, where he leads the development and implementation of Spark’s long-term corporate strategy, including portfolio and technology prioritization, enterprise-wide processes, long-range financial planning and the cultivation of collaborative partnerships to advance Spark programs.

Michael joins Spark Therapeutics from Bain & Company, where he served as a partner in the healthcare practice for a decade. In this role, Michael focused on corporate and business unit strategies, organizational transformations, product launches, growth strategies and new market entries. His experience spans multiple therapeutic areas, including rare disease, the central nervous system and ophthalmology across a wide range of modalities.

Prior to joining Bain in 2010, Michael was a partner at Monitor Group and head of the New York office, where he supported pharmaceutical treatment launches and growth strategies for 10 years. Before that, Michael was senior vice president at Sanofi Diagnostics Pasteur in Paris, France and a senior director at Boehringer Mannheim (now Roche) in Mannheim, Germany.

Michael earned an M.B.A. from the Institut Européen d’Administration des Affaires (INSEAD) and holds a MSc. in molecular biology and a BSc. in biochemistry from the University of Waterloo in Canada.

Blake Sprayberry
Head of Commercial

Blake Sprayberry is the Head of Commercial at Spark Therapeutics, where he is responsible for US commercial operations, commercial development, government affairs, and cross-functional activities related to the commercialization of gene therapies. He brings over 20 years of pharmaceutical and biotech industry experience, including strategy, commercial, and manufacturing.

Blake joined Spark in 2019 as Head of Commercial Development. During his tenure, Blake built the strong team, capabilities, and commercial processes needed to support and advance our gene therapy portfolio. He also led our LUXTURNA partnership with Novartis and the Spark/Roche collaboration effort, which leverages our integrated capabilities in the US and follows the Roche affiliate model outside of the US.

Prior to Spark, Blake served as the Oncology Strategy Lead for Pfizer where he was responsible for leading strategic planning and global projects. Earlier, he held commercial leadership roles at Wyeth and Pfizer, including three new product launches, expansion of the Hemophilia and Regenerative Medicine development portfolios, and leading the rhBMP-2 alliance with Medtronic. Additionally, Blake played a key role in the development of Wyeth’s biotech platform and strategy, and held roles in manufacturing, network strategy, and investment planning for in-line and portfolio biologics.

Blake served as a United States Marine Corps Officer in a variety of leadership and operations roles. He holds a BS in engineering from the US Naval Academy and an MBA from Cornell’s Johnson School of Management.