Scion Team Page Image

The 13 companies our team has been part of founding or building prior to Scion's launch have collectively given rise to 20+ clinical-stage therapeutics, advanced eight into pivotal clinical trials, and generated &gt;$34 billion in combined public equity value and announced M&amp;A proceeds. We are excited to discover what the future holds.

Investment Team

Operations

Innovations

Fellows & Alumni

Sam is a founder and Managing Partner of Scion. He has more than 20 years of experience in the life sciences across roles as an investor, scientist and entrepreneur. From 2013 until October 2019, Sam was a Partner at Apple Tree Partners (ATP) where he focused on creating and building therapeutics companies. During his tenure at ATP, Sam contributed to the formation, financing and build-out of Syntimmune (acquired by Alexion Pharmaceuticals), Stoke Therapeutics (NASDAQ: STOK), Chinook Therapeutics (acquired by Novartis), Marengo Therapeutics and Ascidian Therapeutics and served as a member of each company’s Board of Directors.
Before joining ATP in 2013, Sam was an immunologist at the University of Cambridge in the UK where his research 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 structured investments in development-stage therapeutics. Sam began his career 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.
Sam holds an A.B. in Molecular Biology from Princeton University and completed his M.Phil. and Ph.D. research at the University of Cambridge, where he was a Taylor Research Scholar and was awarded an NSF Graduate Research Fellowship for his work.

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Samuel Hall, PhD

Aaron is a founder and Managing Partner of Scion. Over the past 15 years, he has specialized in founding, building and investing in life sciences companies, focused primarily on therapeutics. Aaron currently serves as a board member of Avalo Therapeutics (NASDAQ: AVTX). Previously, he was a Venture Partner at Medicxi, where he was a founding board member of Centessa Pharmaceuticals PLC (NASDAQ: CNTA), recently acquired by Eli Lilly (NASDAQ: LLY). Prior to launching Scion, he was a co-founder and founding board member of RayzeBio (acquired by Bristol Myers Squibb) and Tourmaline Bio (acquired by Novartis). Collectively, Aaron has been a founding investor/board member of six $1 billion plus M&amp;A transactions totaling over $20B in total cash consideration.
From 2011 until 2019, Aaron was a Partner at Apple Tree Partners (ATP), a life sciences venture capital firm. At ATP, Aaron was a key member of the therapeutics investment team, playing a leading role in launching seven ATP portfolio companies, serving on the Board of Directors of Akero Therapeutics (acquired by Novo Nordisk), Corvidia Therapeutics (acquired by Novo Nordisk) and Syntimmune (acquired by Alexion), as well as two privately held companies (Marengo and Ascidian). During his time at ATP, Aaron was also a board observer at Stoke Therapeutics (NASDAQ: STOK) and led many of ATP’s crossover and public biotech investments. Before joining ATP in 2011, Aaron held various roles in private equity and investment banking.
Aaron received a B.S. in Finance and International Business from NYU’s Stern School of Business.

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Aaron Kantoff

Tadd Wessel is the founder and Managing Partner of Petrichor, a private investment firm focused on the healthcare sector. He is also a founder and Managing Partner of Scion. Tadd has more than 25 years of experience, primarily focused on investing and building companies the life sciences sectors. Previously, he was a Partner at OrbiMed Advisors, where he led the build-out of the structured investment business. Prior to OrbiMed, Tadd was a Vice President at Fortress Investment Group focused on healthcare investments. Tadd began his career in the life sciences investment banking groups at Citigroup and Robertson Stephens.
Tadd has served on more than 30 boards most recently including Aurion Biotech, Cryoport (NASDAQ: CYRX), and ITM. He also serves on the Advisory Board of the AIM at Melanoma Foundation, whose mission is dedicated to finding more effective treatments and, ultimately, the cure for melanoma. He also serves on the Board of the International Centers for Precision Oncology (ICPO) whose mission is to scale access of molecularly targeted precision oncology diagnostics and therapeutics for the benefit of cancer patients globally.
Tadd holds an AB in biology from Princeton University.

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Tadd Wessel

Megan joined Scion in 2025 as a Principal on the investment team. She was previously an investor at Venrock, during which time she co-founded Kelonia Therapeutics (acq. by Eli Lilly) and Iris Medicine. Megan went on to take operating roles at both companies, including serving as Iris Medicine’s President.
Megan has been named to the Forbes 30 Under 30 list for Healthcare and Business Insider’s Under 40 in Biotech. In addition to her work in biotech, Megan serves as a Board Director at multiple non-profits dedicated to advancing scientific research, including Convergent Research and the Hertz Foundation.
She received her PhD as a Hertz Fellow from the Scripps Research Institute, and that work contributed to the formation of Vividion Therapeutics (acq. by Bayer). She received an AB/AM from Harvard, where she studied chemistry.

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Megan Blewett

William is an Associate at Scion. Prior to joining the Scion investment team in a full-time capacity William worked with the firm as a member of the inaugural cohort of Scion Fellows. 
William holds an M.D. from the Keck School of Medicine of USC and a Ph.D. from the California Institute of Technology, where he worked in the laboratory of James R. Heath to develop immunotherapy technologies for oncology and COVID-19. He received his A.B. in Chemistry from Princeton University.

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William Chour, MD, PhD

Jeff Edelman is Partner &amp; Head of Operations at Scion and also serves as Chief Compliance Officer for both Scion and Petrichor. He joined Scion in 2025 to lead fund operations and support the firm’s investment team and its portfolio companies, including Scion Innovations. Jeff brings more than 30 years of experience across healthcare investing and operating leadership. Previously, he was Co-Founder, CFO &amp; Chief Compliance Officer of Pavadi Capital and Co-Founder, COO &amp; CFO of Symphony Capital. Earlier in his career, he held roles at Alex. Brown, McKinsey, L.E.K. Consulting, Investcorp, and multiple healthcare startups. Over the course of his career, Jeff has raised more than $500 million of institutional capital across public and private healthcare strategies. He received his MBA from The Wharton School and his BA in Economics from Dartmouth College.

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Jeffrey Edelman

Lalo Flores is a Venture Partner at Scion Life Sciences and CEO of Flux Therapeutics, a Scion portfolio company. Lalo has more than 30 years of experience in the Biopharmaceutical industry, both as entrepreneur and R&amp;D executive. He began his career in industry with Tularik, a biotechnology company acquired by Amgen in 2004, as one of the initial employees. Subsequently, Lalo held multiple senior R&amp;D leadership roles at Merck and Johnson and Johnson, advancing multiple drug candidates into early and late development, spanning various therapeutic areas. His extensive operational experience as company builder includes roles as co-founder, President and CSO of Novira Therapeutics, a biotechnology company that was acquired in an all cash transaction by Johnson and Johnson in 2015, and as founding CEO of Century Therapeutics (NASDAQ: IPSC), a biotechnology company developing allogeneic cell therapies for cancer and auto-immune disorders that he took public in 2021 and led since its inception in 2018 until 2023. 
Lalo received a doctorate in Biochemistry and Molecular Biology from Rutgers University and performed Post-Doctoral work at the Salk Institute.

Lalo Flores

Lalo Flores, PhD

Sam is an Associate at Scion. Prior to joining the firm in April 2023, Sam was a postdoctoral fellow in the laboratory of David Baker within the Institute of Protein Design at the University of Washington. Sam holds a B.A. in Chemistry and Mathematics from Amherst College, and a Ph.D. in Biological Chemistry from MIT, where he was an NSF Graduate Research Fellow.

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Samuel Hendel, PhD

Andreas is a Partner at Scion. He is a 20+-year industry veteran, with protein engineering and structural biology expertise at large and small pharma. Before joining the firm, he was the founder and CSO of Marengo Therapeutics, a developer of transformational protein therapeutics targeting TCRvβ chains for cancer. Previously, he led New Technologies for Biologics at Novartis, heading a research group responsible for the discovery and development of complex biologics, cell, gene and nucleic acid therapies.
In addition to discovering many innovative protein therapeutics, he was the principal inventor of core technologies that established Novartis’ adoptive T-cell therapy portfolio that ultimately led to the first FDA-approved CAR-T product, Kymriah. At Abbott Laboratories, he was instrumental in solving the crystal structure of Humira bound to its target TNF. Andreas is an inventor on &gt;450 patents and patent applications.
Andreas received his Ph.D. in Germany at the University of Bayreuth followed by post-doctoral education in biochemistry and structural biology at the University of Illinois, Birkbeck College London and UT Southwestern Medical Center, Dallas TX. He received the prestigious Novartis VIVA award for his many contributions to the life sciences.

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Andreas Loew, PhD

Huw is a Venture Partner of Scion. He has more than 27 years of experience establishing, funding, and leading start-up biotechnology companies. From October 2014 to October 2017, Huw was the founding CEO of Stoke Therapeutics, Inc. (NASDAQ: STOK) and was an Entrepreneur-in-Residence at Apple Tree Partners (ATP). From October 2017 until September 2024, Huw was the Chief Operating Officer (COO) and Chief Business Officer (CBO) of Stoke. Prior to Stoke, Huw was a co-founder and Vice President of Corporate Development of Aileron Therapeutics (NASDAQ: ALRN) from 2005 through 2013. He was also a founding scientist of NeoGenesis Pharmaceuticals in 1997, where he served as Vice President of External Collaborations prior to the company’s acquisition by Schering-Plough in 2005.
Huw received his B.A. in Biochemical Sciences from Harvard College and received his Ph.D. in Organic Chemistry from Harvard University.

Huw Nash

Huw Nash, PhD

Romesh is a Venture Partner at Scion Life Sciences. He brings over 20 years of experience in pharma and biotech as a scientist, founder and entrepreneur. He founded and led companies developing nucleic acid therapeutics, biologics and antibody conjugates. Prior to joining Scion Life Sciences, Romesh was President and CEO of Ascidian Therapeutics developing RNA exon editing medicines. Previously, he was an EIR at Atlas Ventures and the founding CEO of Dyne Therapeutics (NASDAQ: DYN) which develops antibody conjugates for neuromuscular diseases. While at Atlas Venture he also co-founded and led R&amp;D at RaNA Therapeutics, later known as Translate Bio (NASDAQ: TBIO) and acquired by Sanofi (NASDAQ: SNY). Prior to Atlas Ventures, Romesh led mRNA and antibody therapeutics at Alexion and developed nucleic acid therapies for metabolic disease and oncology at Pfizer.
Romesh obtained his B.S. from Loyola College, an M.S. from Duke University, and a Ph.D. from Emory University.

Romesh Subramanian

Romesh Subramanian, PhD

Elliot is an Associate at Scion. Prior to joining the firm in a full-time capacity, Elliot completed fellowships at Scion, Flagship Pioneering, and Vida Ventures. Elliot holds a B.A. in Biochemistry from Claremont Mckenna College, and Ph.D. From the Scripps Research Institute, where he worked in the laboratory of Peter Schultz.

Elliot Warner

Elliot Warner, PhD

Eddie Hossein is Director of Finance at Petrichor. He previously served as Controller at Colbeck Capital Management and DiMaio Ahmad Capital, in addition to earlier roles at PricewaterhouseCoopers and JP Morgan Chase. Mr. Hossein holds a dual degree in Economics and Accounting from the Queens College of CUNY.

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Eddie Hossein

David Katona is the Head of Business Development and Investor Relations at Petrichor. Dave has 20+ years of capital formation experience and leads all marketing, development, and fundraising initiatives for Petrichor and affiliate firm Scion. Prior to joining Petrichor in March 2021, Dave was part of the Capital Introductions Group at Jefferies Group, where he managed institutional relationships, spanning endowments, foundations, family offices, and others. He also ran the group’s uncorrelated/niche co-investment outreach programs. Previously, Dave was a Partner at Abundance Partners. He holds a Bachelors of Arts degree in Political Science with a concentration in Economics from Bates College.

Team

United by our conviction in the power of therapeutic innovation to improve human health.

Meet the Scion team

2022/23 Fellowship Alumni

2023/24 Fellows

2024/25 Fellows