Vaxil Scientists

Dr. Ari S. Kellen MD Vaxil

Dr. Ari S. Kellen, M.D. – Director

Medical Doctor, University of Witwatersrand | MBA, University of Witwatersrand

Dr. Ari Kellen is a seasoned senior executive with over three decades of healthcare industry experience, both in management consulting and in major global P&L operational roles. Dr. Kellen trained and worked as a physician in South Africa while also running a large segment of a 1,000 bed teaching hospital. After being recruited by McKinsey & Company, he spent 23 years serving healthcare clients around the world. Dr. Kellen served for more than a decade as a Senior Partner at McKinsey, advising CEOs and Board members at large industry-leading healthcare companies and small rapidly growing entities. His experience spans biotechnology, medical device, payor and provider organizations, and includes work focused on M&A, business development, new company spin-outs, corporate and business unit level turnarounds, R&D portfolio strategy, and product / therapeutic area growth strategies. In 2014, Dr. Kellen was recruited to Bausch + Lomb / Valeant where he ran a multi-billion dollar P&L across the US and Latin America. As EVP and General Manager of US Bausch + Lomb, he successfully launched and commercialized new products in Pharmaceuticals, Surgical, and Vision Care / Contact Lenses. Dr. Kellen was also responsible for leading the United States R&D organization to advance more than 100 active R&D projects across Dermatology, Ophthalmology, Gastroenterology, Oncology and Consumer Products. Dr. Kellen currently serves on the Advisory Boards of Paragon Biosciences and Castle Creek Pharmaceuticals.


Dr. Riva Kovjazin, M.D. – Senior Scientist

M.D., Perm State School of Medicine | Immunology Research Fellow, Rostov Research Institute | Research Fellow, Center for Clinical Immunology, Moscow School of Medicine
Dr. Riva Kovjazin is an expert in the field of immunology with over 25 years of experience in cellular immunology. She obtained her M.D. from the Perm State University School of Medicine, one of the oldest universities in Russia. Dr. Kovjazin then specialized in the advanced study of immunology and epidemiology of conventional infectious diseases at the Rostov Research Institute. In addition, she was a project leader at the Center for clinical immunology, University of Medicine, Moscow, Russia where she studied Clinical immunology and diagnosis aspects of HIV. From 1997 until 2007, Dr. Kovjazin held various positions at XTL Biopharmaceutical



Dr. Shawn Langer MD Vaxil

Dr. Shawn Langer, M.D.

Dr. Shawn Langer brings over two decades of healthcare industry experience. Dr. Langer was Senior Partner at McKinsey & Company, where he was the leader of its Healthcare Private Equity Group.

During his 15 years with McKinsey & Company, Dr. Langer served healthcare clients across pharmaceuticals, biotechnology, medical devices, and healthcare services.

Most recently Dr. Langer has spent nearly 5 years investing in innovative healthcare companies in his capacity as a portfolio manager at healthcare private equity investment firm BMHS Investments.



Mordechai Applebaum, PhD MA – R&D Director

Dr. Mordechai Applebaum is an expert in the fields of molecular biology and immunology. Dr. Applebaum completed his doctorate dissertation at The Hebrew University of Jerusalem in the field of embryonic development and molecular biology. Upon completion of his studies he joined Enlivex Therapeutics as a senior scientist and project manager leading the application of the company’s product in novel indications. His activities expanded to include management of preclinical studies, regulatory affairs and business development. He served as VP of content and public relation at JLM-BioCity and a member of the steering committee. Dr. Applebaum also holds an MA in philosophy from The Hebrew University.

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