John Hastewell


John Hastewell served in a series of wide-ranging roles in his nearly 30 years at Novartis. Most recently, he was the Head of Novartis Institutes for Biomedical Research (NIBR) Biologics Center where he was responsible for the discovery of antibody, protein, and nucleic acid-based therapeutics. Formerly, he was the Global Head of the Program Office where he worked on NIBR’s research strategy and portfolio management and oversaw the company’s strategic focus on building their biologics drug pipeline. Before working at NIBR, Dr. Hastewell also served in several leadership roles at Novartis based in the UK, including Head of Thrombosis Research, leadership of biochemistry and pharmacology, as well as overseeing all respiratory research disease projects to ensure rapid and effective translation to the clinic. He was also the Head of a strategy team defining the company’s long-term research direction and led the Immunology Platform across all Novartis disease areas.

Rupert Vessey


Rupert Vessey is the the Executive Vice President and President of Global Research and Early Development at Celgene, where he is responsible for the oversight of all internal and external discovery research, preclinical development, and early clinical development. Before joining Celgene, Dr. Vessey was Senior Vice President of Early Development and Discovery Sciences at Merck where he was responsible for numerous drug development programs. He also served as Senior Vice President and Head of Early Development and Discovery Sciences, Senior Vice President and Head of the MRL Respiratory and Immunology Franchise, Vice President Drug Discovery and Site Head for MRL Boston and for MRL Kenilworth before that. Prior to his ten years at Merck, Dr. Vessey worked in drug discovery, experimental medicine, and early clinical development at GlaxoSmithKline where he served as Vice President, Target Discovery and Senior Director, Discovery Medicine.

Seth Harrison


Seth Harrison is the Founder and Managing Partner of Apple Tree Partners (ATP). He has invested in life sciences since 1991. He is currently the Chairman of ATP companies Braeburn Pharmaceuticals, Stoke Therapeutics, and Limelight Bio. His prior investments include: Syntimmune, Aileron Therapeutics, ArQule, Coelacanth, Cyrano Sciences, Gloucester Pharmaceuticals, HeartWare International, Informed Access, SGX Pharmaceuticals, Tokai Pharmaceuticals, Ultracision, and ViroPharma. From 2002 to 2010, he also served on the board of the International Partnership for Microbicides. Prior to founding ATP in 1999, Seth was a general partner at Oak Investment Partners, and before that a venture partner at Sevin Rosen Funds.

Sam Hall


Sam Hall is a Partner at Apple Tree Partners (ATP). Prior to joining ATP in 2013, Sam was a researcher at the University of Cambridge in the U.K., where his work focused on novel therapeutic strategies for autoimmune diseases. Previously, Sam was a member of the investment team at Symphony Capital, a private equity firm dedicated to investments in biopharmaceutical development. Prior to Symphony, he served as a member of the healthcare investment banking team at Citigroup, where he advised leading biotechnology, medical device and healthcare services businesses on numerous completed strategic and debt and equity financing engagements. In addition to Elstar, Sam serves on the boards of Stoke Therapeutics, Limelight Bio and was a board director at Syntimmune.

Steve Arkinstall

President and CEO

Andreas Loew

Founder and CSO