Team / Board of Directors

Board of Directors

Leslie Williams, BS, RN, MBA
Director, Founder, President and Chief Executive Officer

Leslie Williams has more than 25 years of industry experience in healthcare, management, commercial product development and marketing. In 2010 she founded ImmusanT, Inc., which subsequently acquired the assets of Melbourne, Australia based Nexpep. She has built and led the team since inception. In 2015 Williams received the Distinguished Alumni Achievement Award from the University of Iowa in recognition of her accomplishments in her professional life. Prior to founding ImmusanT, she was President & CEO of Ventaira Pharmaceuticals, which became a significant player in the pulmonary drug delivery market under her leadership. While President & CEO of Ventaira Pharmaceuticals, she was recognized as one of the top 100 leaders in life sciences by PharmaVOICE magazine.

Prior to Ventaira, Ms. Williams served as director of marketing for INO Therapeutics, Inc., where she played a significant role in the NDA submission for INOmax (nitric oxide) for inhalation, a drug for the treatment of pulmonary hypertension. Responsible for the commercial aspects of INOmax’s US market introduction, from setting objectives and strategy to developing key constituency groups and expert advisory boards, as well as representing INO Therapeutics on Capitol Hill, Williams also assisted with expansion of the INO-therapy platform into the European marketplace. The company was acquired by Ikaria Holdings in 2007. Ms. Williams’ prior pharmaceutical industry experience includes commercial positions at Merck and GlaxoSmithKline, and drug-delivery and -monitoring experience at Datex-Ohmeda (formerly Ohmeda, Inc.). She was a venture partner at Battelle Ventures where she sourced and evaluated deals and assisted early-stage technology companies with strategy, management, business development and M&A. She served on the Boards of Hepregen Corporation and CDI Bioscience. She currently serves on the Advisory Board of The Capital Network (TCN) and is on the Executive Board of the University of Iowa School of Pharmacy. She also serves on the Editorial Advisory Board of Life Science Leader as well as The Journal of Advanced Therapies and Medical Innovation Sciences. In addition, she serves as a mentor in the Boston University Kindle Program.

Ms. Williams holds an MBA from Washington University, John Olin School of Business, and a BS degree with honors in nursing from the University of Iowa. Before entering industry, she was a critical-care nurse at Duke University, Medical College of Virginia and at the University of Iowa.


Kevin Ferro
CEO, Vatera Capital Management LLC
Chairman, ImmusanT Board

Kevin Ferro is the Chief Executive Officer and Managing Member of Vatera Capital Management LLC, and a Co-Founder of Vatera Healthcare Partners. In addition to being the Chairman of the Board of Directors of ImmusanT, Inc., Mr. Ferro is the Chairman of the Board of Directors for Melinta Therapeutics, Inc. as well as an observer on the Board of Directors for Alvogen. Mr. Ferro was Chairman of the Board of Directors for Pearl Therapeutics, Inc. until its sale to AstraZeneca in July 2013 and a member of the Board of Directors of Kos Pharmaceuticals, Inc. until its sale to Abbott Laboratories in 2006.

Prior to forming Vatera Capital Management, Mr. Ferro founded and managed Vatera Holdings LLC, a family office advisor. Previously, Mr. Ferro founded Ferro Capital LLC, an investment advisory firm, in 2001. Prior to that, Mr. Ferro was the Global Head of Alternative Investment Strategies for Commerzbank AG, Germany’s second-largest listed bank, where he managed alternative investment programs for the bank and its clients. Prior to Commerzbank, Mr. Ferro was a Vice President at D. E. Shaw & Co., LP (1994-1998).

Mr. Ferro holds an AB in government from Harvard College.


Thomas O. Daniel, MD
Venture Partner, ARCH Venture Partners

Dr. Daniel has contributed to improving healthcare as physician, educator, basic and translational scientist and, most recently, as a senior research and development executive in biotechnology and biopharmaceutical companies. He is currently Chairman of Vividion Therapeutics, is a venture partner at ARCH Venture Partners, and serves as director at Zafgen, Inc., JUNO Therapeutics, Magenta Therapeutics, and VIR Bio. Dr. Daniel is a Trustee of Reed College, advises the Parker Institute for Cancer Research, is a director of the Alliance for Lupus Research and serves as a member of the Biomedical Science Advisory Board of Vanderbilt University Medical Center.

He was recently Chairman of Research at Celgene Corporation, and served as President of Research and Early Development at Celgene over the past decade. Previously, he served as Chief Scientific Officer and Director at Ambrx Inc., was Vice President of Research at Amgen, and Senior Vice President of Discovery Research at Immunex. A nephrologist and former academic investigator, Dr. Daniel was C.M. Hakim Professor of Medicine and Cell Biology at Vanderbilt University and co-director of the Vanderbilt Medical Scientist Training Program (MD/PhD Program).

He formerly led NIH supported research groups, conducted research in the Howard Hughes Medical Institute, earned his M.D. from the University of Texas, Southwestern, and completed medical residency at Massachusetts General Hospital.



Steven Gillis, PhD
Managing Director, Seattle, ARCH Venture Partners

Steven Gillis, Ph.D. is a Managing Director at ARCH Venture Partners. In addition to being a member of the Board of Directors of ImmusanT, Inc., he represents ARCH as a director on the boards of multiple public and private companies. He has served as acting CEO of several ARCH investments and is currently chairman of Lycera Corporation, VBI Vaccines, PhaseRx, OncoRespsone and Codiak BioSciences.

Dr. Gillis was a founder and director of Corixa Corp. and served as CEO from its inception and as its Chairman from 1999 until its acquisition by GlaxoSmithKline. Prior to Corixa, Dr. Gillis was a founder and director of Immunex Corp., the most successful venture-funded biotech company in the state of Washington. During his time at Immunex he served as Director of Research and Development, Chief Scientific Officer, and as CEO of Immunex's R&D subsidiary. Dr. Gillis was interim CEO of Immunex following its majority purchase by American Cyanamid Co. and remained a member of the board until 1997.

Dr. Gillis is an immunologist by training and holds a B.A. from Williams College and a Ph.D. from Dartmouth College.


Justin Sun
Managing Director, Vatera Capital Management LLC

Justin Sun is a Managing Director of Vatera Capital Management LLC and is responsible for sourcing new investments and overseeing existing investments. Mr. Sun serves on the Board of Directors of ImmusanT, Inc. and previously served on the Board of Directors of Edgemont Pharmaceuticals, LLC.

Prior to joining Vatera, Mr. Sun was an Analyst at Aisling Capital, a leading private equity fund exclusively dedicated to life sciences investing. Mr. Sun started his career in the Healthcare Investment Banking Division at Thomas Weisel Partners where he focused on M&A and equity financing transactions across the healthcare industry.

Mr. Sun holds a BA in economics from Yale University.


Thomas Koestler, PhD
Venture Partner, Vatera Healthcare Partners LLC

Dr. Thomas Koestler is a Venture Partner of Vatera Healthcare Partners LLC. Dr. Koestler serves on the Board of Directors of ImmusanT, Inc., Melinta Therapeutics, Inc., and Momenta Pharmaceuticals Inc. Dr. Koestler previously served on the Board of Directors of Edgemont Pharmaceuticals, LLC, Pearl Therapeutics, Inc. until its sale to AstraZeneca in July 2013, Novo Nordisk A/S and ReSearch Pharmaceutical Services, Inc. until its sale to KKR in September 2013. Dr. Koestler served as an executive director of Vatera Holdings LLC from February 2010 to December 2018.

In his nearly 30-year career in the pharmaceutical industry, Dr. Koestler established a track record of building high-performance teams that drove global success in research and development. Most recently he served as Executive Vice President of Schering-Plough Corporation and President of Schering-Plough Research Institute (SPRI), the pharmaceutical Research and Development arm of Schering-Plough Corporation. Under his leadership, the company developed an industry-leading pipeline that contributed to the turnaround of the business. Dr. Koestler’s accomplishments include over 80 product approvals including over 30 New Molecular Entities. Before joining Schering-Plough, he was Senior Vice President, Global Head Regulatory Affairs for Pharmacia Corporation. Prior to joining Pharmacia, Dr. Koestler was Senior Vice President, Global Head Drug Regulatory Affairs/Compliance Assurance Professionals for Novartis Pharmaceuticals Corporation. Before joining Novartis, he was Senior Director, Drug Regulatory Affairs at Ortho-McNeil Pharmaceutical Corporation and Director, Regulatory Affairs, Pharmaceutical Research and Development Division at Bristol-Myers Squibb Company and Westwood Pharmaceuticals, Inc.

Dr. Koestler holds a BS in biology from Daemen College and a PhD in medicine/pathology from the State University at Buffalo, Roswell Park Memorial Institute.

Robert J. Perez

Robert J. Perez
Founder and Managing Partner, Vineyard Sound Advisors
Founder and Chairman, Life Science Cares

Robert J. Perez is a biopharmaceutical operating executive with more than 25 years of experience in the industry. He is currently the Founder and Managing Partner of Vineyard Sound Advisors, LLC as well as the Founder and Chairman of Life Science Cares.

Previously, he was the Chief Executive Officer of Cubist Pharmaceuticals, Inc., a public pharmaceutical development company, when the company was acquired by Merck in January 2015. He joined Cubist in August 2003 as Senior Vice President, Sales and Marketing, and led the launch of Cubicin® (daptomycin for injection).

He also served as Executive Vice President and Chief Operating Officer, and President prior to becoming CEO. Before joining Cubist, he served as Vice President of Biogen, Inc.’s US CNS business unit, where he was responsible for commercial leadership of an $800 million business. He joined Biogen in 1995 and was one of the architects of the commercial model that launched the company’s first commercial product, AVONEX®.

Prior to Biogen, Mr. Perez held various sales and marketing positions at Zeneca Pharmaceuticals. Along with ImmusanT, Mr. Perez serves as a member of the board of directors of AMAG Pharmaceuticals, Inc., Cidara Therapeutics, Inc., Zafgen, Inc., Spark Therapeutics, Inc. and Unum Therapeutics Inc. Rob is currently serving as the Executive Chairman of Akili Interactive Labs, Inc.

Mr. Perez is also a member of the Board of Trustees at The Dana Farber Cancer Institute, Inc.

Mr. Perez received a B.S. in business from California State University, Los Angeles and an M.B.A. from the Anderson Graduate School of Management at the University of California, Los Angeles.