Petrichor Team

Petrichor Capital Partners

Scion Life Sciences

Operations

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 Life Sciences, an affiliate of Petrichor. Tadd has more than 25 years of experience, primarily focused on investing and building companies in 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

Patrick Lally has over 15 years of healthcare investing experience. He joined Petrichor as a Partner at launch, and he is responsible for all aspects of the Fund’s investing activities including origination, diligence, and asset management. Patrick participates on the boards of Aurion Biotech, CorneaGen, ITM, Persivia, and Vero.
Prior to Petrichor, Patrick was an investor in the healthcare special situations and structured finance business at OrbiMed Advisors. Previously, he was focused on healthcare investments in the Drawbridge Special Opportunities Fund at Fortress Investment Group. Patrick began his career at Barclays Capital, where he worked in the capital markets and leveraged finance teams.
Patrick holds an M.B.A. from The Wharton School at the University of Pennsylvania and an A.B. in Molecular Biology from Princeton University.

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Patrick Lally

Michael Beecham has over a decade of healthcare investment and consulting experience. He joined Petrichor as a Partner at launch. Michael is responsible for investment in companies across the healthcare and life science ecosystem, from investment origination, management and strategic exit. Michael is currently on the boards of Ascend Gene and Cell Therapy, Fennec Pharmaceuticals (Nasdaq: FENC) and Leukocare AG. Previously, He participated on the boards of Cryoport (Nasdaq: CYRX) and Clearpoint (Nasdaq: CLPT), both successful, fully-realized exits.
Prior to Petrichor, Michael was at OrbiMed, working with Tadd and Patrick on the healthcare special situations and structured finance team. Additionally, he was an investment manager at Vatera Healthcare Partners, where he was responsible for sourcing and managing life science investments across preclinical through commercial stage, both public and private. Prior to that, Michael was at American Capital on the healthcare leveraged buyouts team (now part of Ares). He was also previously at Royalty Pharma (Nasdaq: RPRX) and Navigant Consulting (previously Easton Associates).
Michael has a B.S.E. in Bioengineering from the University of Pennsylvania.

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Michael Beecham

Hayden Fownes joined Petrichor at launch in 2018 and is a Vice President on the investment team. He supports all aspects of investment sourcing, execution, portfolio management, and fund operations for Petrichor Capital Partners. Hayden was previously in the Global Healthcare Investment Banking group at Bank of America Merrill Lynch, focused on M&amp;A and financings for clients across all healthcare and life sciences subsectors. He holds a B.S. in Finance from Wake Forest University.

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Hayden Fownes

Lucy Burke is a Senior Associate at Petrichor. Prior to joining Petrichor, Lucy worked as an associate at MTS Health Partners, a boutique investment bank focused exclusively on the healthcare industry, where she was involved in M&amp;A and equity financings across healthcare services and life sciences. She holds a B.A. in Psychology from Dartmouth College.

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Lucy Burke

Thomas Leichner is an Associate at Petrichor. Prior to joining Petrichor, Thomas worked as Chief of Staff focusing on Business Development, Strategy and Investor Relations at Insilico Medicine. Prior to Insilico, Thomas began his career in Life Sciences Investment Banking at Locust Walk. He holds a B.A. in Biology from the University of Pennsylvania.

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Thomas Leichner

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. In addition to his professional responsibilities, Sam serves as a Director of the Burke Neurological Institute, an independent neuroscience research institute affiliated with Weill Cornell Medicine.
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. He has spent over a decade specializing in founding, building and investing in life sciences companies, focusing primarily on therapeutics. Aaron currently serves as a board member of Tourmaline Bio (NASDAQ: TRML), where he has been serving since the company’s inception. Previously, he was a Venture Partner at Medicxi, where he was a founding board member of Centessa Pharmaceuticals PLC (NASDAQ: CNTA) and assisted the team with other privately held therapeutics investments. Before joining Medicxi, he was a co-founder and founding board member of RayzeBio (NASDAQ: RYZB), which was recently acquired by Bristol Myers Squibb (NYSE: BMY). 
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 practice, playing a leading role in assembling several ATP portfolio companies, and most notably, serving on the boards of Akero Therapeutics (NASDAQ: AKRO), 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 Stern’s School of Business.

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Aaron Kantoff

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

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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Wiliam Chour, MD, 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

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.

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Elliot Warner, PhD

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 Life Sciences. Prior to joining Petrichor in March 2021, Dave was part of the Capital Intelligence team at Jefferies LLC, where he managed institutional investor relationships, spanning endowments, foundations, family offices, and others. He also ran the group’s uncorrelated/niche and co-investment outreach programs. Previously, Dave was a Partner at Abundance Partners. Dave holds a Bachelor of Arts degree in Political Science with a concentration in Economics from Bates College.

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David Katona

Eidul (Eddie) Hossein has over 20 years of experience in financial, operational, and administrative areas in the alternative investment industry. At Petrichor Eddie is responsible for finance administration, including accounting, reporting, budgeting, treasury management, and various compliance activities. Prior to joining Petrichor, Eddie was the Controller Colbeck Capital Management and DiMaio Ahmad Capital, alternative investment management firms specializing in credit products. He also held various positions at PricewaterhouseCoopers and JPMorgan Chase. He holds a dual Bachelor of Business Administration degree in Accounting Information Systems and Economics from the Queens College of the City University of New York.

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Eidul Hossein

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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Thomas Leichner

Thomas Leichner