Our team brings together unparalleled expertise in mitochondrial biology
Pretzel was founded by some of the world’s foremost researchers in mitochondrial biology and is led by accomplished experts in drug discovery, drug development, and company foundation. Our deep expertise in mitochondrial biology enables us to potentially address a wider range of diseases driven by mitochondrial dysfunction than ever before.
The name Pretzel is inspired by the focal point of our science, the mitochondrion, whose twisting inner-membrane is one of many fascinating features that make it unlike any other organelle in the body.
John Walker is a leading figure in the world of biochemistry and is the Director Emeritus and Professor Emeritus of Molecular Bioenergetics at the MRC Mitochondrial Biology Unit in the University of Cambridge. In 1994, his work, conducted at the MRC Laboratory of Molecular Biology in Cambridge, on a complex molecular machine in the mitochondria, known as the ATP synthase, led to the realization that the energy provided by the oxidation (controlled burning) of dietary sugars and fats is coupled by a mechanical rotary mechanism to generate the 60 kg of ATP that each of us makes daily to sustain our lives. This work led to the award of the Nobel Prize in Chemistry in 1997.
In 1998, John was appointed Director of the MRC Dunn Human Nutrition Unit in Cambridge, which became the MRC Mitochondrial Biology Unit in 2008. In 1999, he was knighted for his services to Science. He is a Fellow of the Royal Society, and in 2012, he received its Copley Medal, the UK’s highest scientific accolade. He is also a Fellow of the Academy of Medical Sciences, a Fellow of Sidney Sussex College, Cambridge, an Honorary Fellow of St Catherine’s College, Oxford, a Foreign Member of L’Accademia Nazionale dei Lincei in Rome, of the Royal Netherlands Academy of Arts and Sciences, and of the Royal Society of New Zealand, and a Foreign Associate of the U.S. National Academy of Sciences. His numerous accolades also include the Biochemical Society’s Keilin Medal, the Peter Mitchell Medal and the Messel Medal of the Society of Chemistry and Industry. He has received 16 honorary doctorates from universities around the world including in 2021 the Honorary Degree of Doctor of Science honoris causa from the University of Cambridge.
John studied chemistry St. Catherine's College at the University of Oxford where he obtained a B.A. degree in 1965. In 1969, he was awarded a D.Phil. in biochemistry by the University of Oxford for research on peptide antibiotics conducted at the Sir William Dunn School of Pathology.
Rebekah Hailes is a Program Manager at Pretzel Therapeutics. She received her M.S. and Ph.D. in chemistry from the University of Bristol, UK. Rebekah completed her postdoctoral fellowship at Chalmers University in Sweden.
Gabriel Martinez is Chief Scientific Officer of Pretzel Therapeutics. Previously he was Vice President at Praxis Precision Medicines, Inc., Director of Chemistry at Sage Therapeutics, Principal Scientist and Team Leader at AstraZeneca, and Senior Scientist at Vertex Pharmaceuticals. Gabriel earned his B.S. from the Universitat de Barcelona and Ph.D. from Queen Mary University of London.
Michal Minczuk is a program leader and MRC investigator at the MRC Mitochondrial Biology Unit, University of Cambridge, and an expert in mitochondrial genome engineering with more than 20 years of experience in biotechnology. At Cambridge, Michal leads the Mitochondrial Genetics program. His work is focused on discovering the genetic links between mitochondrial dysfunction and human disease, with a focus on mitochondrial genome engineering. Michal’s laboratory has made profound contributions to establishing the genetic basis and molecular mechanisms of mitochondrial disorders resulting from defects of mitochondrial gene expression. He holds a Ph.D. from the University of Warsaw and conducted postdoctoral training at the MRC Laboratory of Molecular Biology in Cambridge.
Xie Xie is a Scientist at Pretzel Therapeutics. She received her B.S. in biological science and biotechnology from Tsinghua University in Beijing and her Ph.D. in biological sciences from Fordham University in New York City.
Baruch Harris is Chief Operating Officer of Pretzel Therapeutics. He previously served as Senior Vice President of Business Development and Operations at ROME Therapeutics, Senior Advisor of Business Development at Yumanity Therapeutics, Chief Operating Officer at Metera Pharmaceuticals and Chief Business Officer at Enlight Biosciences. He has deep expertise across business development, investor relations, fundraising, program leadership, and commercial and finance functions within the biotechnology industry.
Baruch received his Ph.D. in biochemistry & molecular biology from the University of California, San Francisco, where he was a Howard Hughes Predoctoral Fellow, and his Sc.B. in biophysics from Brown University.
Roger Kornberg is a pioneer in biochemistry, genetics, and molecular biology. Roger’s research has made essential contributions to scientific understanding of eukaryotic transcription, for which he earned the Nobel Prize in Chemistry in 2006.
Roger was elected to the National Academy of Sciences in 1993. He has received many awards, including the Welch prize (2001), the highest award in chemistry in the United States, and the Leopold Mayer Prize (2002), the highest award in biomedical sciences of the French Academy of Sciences.
Roger holds a B.A. in chemistry from Harvard University and a Ph.D. in chemistry from Stanford University. He completed postdoctoral research at the Laboratory of Molecular Biology in Cambridge, England, where he discovered the nucleosome, the basic unit of DNA coiling in chromosomes.
Medha Kapil serves as Head of Legal & SVP of Corporate Development for Pretzel Therapeutics. She oversees all legal matters for the company, leads the internal and external legal teams and business development activities. Prior to joining Pretzel Therapeutics, Medha was Head of Legal and Corporate Development at BioMotiv, an early-stage venture development platform; Associate Counsel at Explorys, an IBM Company and spin-off of Cleveland Clinic Innovations; and Associate Attorney in the Emerging Companies Group at Thompson Hine, LLP. Medha has expertise in scaling startups, establishing teams and cultures, negotiating complex deals, and developing strategy. In 2020, she was recognized as one of Crain’s 40 under 40, acknowledged as “an ambassador to the field”.
Medha holds a J.D. from Case Western Reserve University School of Law and a B.S. in accounting from Elmhurst College.
Kristina Burow is a Managing Director at ARCH Venture Partners. She is focused on the creation and development of biotechnology, pharmaceutical and health tech companies. Since joining ARCH in 2002, Kristina has risen from Associate to Managing Director and has played a significant role in the growth of ARCH’s life sciences portfolio, including multiple public companies exceeding billion-dollar valuations.
In addition to Pretzel, she is a Director of Beam Therapeutics (BEAM), Gossamer Bio (GOSS), Scholar Rock (SRRK), Boundless Bio, Autobahn Therapeutics, ROME Therapeutics, Neumora Therapeutics, and Treeline Biosciences, among others. Kristina previously was a co-founder and Director of Receptos (RCPT – acquired by Celgene) and was a Director of Vir Biotechnology (VIR), Vividion Therapeutics (acquired by Bayer AG), and Epirium Bio among others. She has participated and led investments in a few other ARCH portfolio companies including Interline Therapeutics, Erasca (ERAS), Dewpoint Therapeutics, Aledade, Kura Oncology (KURA), Kythera Biopharmaceuticals (KYTH – acquired by Allergan), and Ikaria (acquired by Mallinckrodt).
Prior to joining ARCH, Kristina was an Associate with the Novartis BioVenture Fund in San Diego. As an early employee at the Genomics Institute of the Novartis Research Foundation (GNF), she directed Chemistry Operations and was active in Business Development where she helped create numerous companies as spinouts from GNF.
Kristina holds an MBA from the University of Chicago, an M.A. in chemistry from Columbia University and a B.S. in chemistry from the University of California, Berkeley.
Alaa Halawa is an Executive Director in the San Francisco Bay Area-based venture capital business of Mubadala Capital (Mubadala Ventures), where he focuses on investing in venture and early growth-stage companies at the intersection of life sciences and technology. Among various themes in life sciences investing, Alaa has concentrated on the following: how technology is enhancing the pharmaceutical industry, from drug discovery through drug development; and how technology — and in particular bio-informatics, artificial intelligence, and machine learning — is enhancing disease diagnosis and healthcare delivery.
Alaa joined Mubadala in 2009 where he worked on designing and implementing the strategy to develop a technology cluster in Abu Dhabi focusing on semiconductor research through partnerships with Silicon Valley companies and academic institutions. Alaa then moved to the Bay Area to support the transition of executive leadership in one of Mubadala's key assets in Silicon Valley, GlobalFoundries, where he worked on a series of strategic, corporate development and transformation initiatives.
Alaa holds an MBA from Cornell University and a B.A. in electrical engineering from University of Jordan.
Claes Gustafsson is professor of medical biochemistry at the University of Gothenburg and a leading expert in mitochondrial gene expression with 30 years of experience in medical biochemistry. His laboratory investigates various aspects of mitochondrial molecular genetics, with a focus on gene transcription and the link between transcription and DNA replication. His expansive work can be found published in journals such as Nature, Cell, and Molecular Cell. Claes is a member of the Royal Swedish Academy of Sciences. He holds an M.D. and Ph.D. in medical biochemistry from the University of Gothenburg.
Per Samuelsson is a Partner at HealthCap. Prior to joining HealthCap in 2000, he gained over 15 years of investment banking experience, mainly with ABB Aros Securities in Sweden. In his last position with ABB Aros Securities, as a Director in the firm’s corporate finance department, Per specialized in the areas of merger transactions, initial public offerings, and equity incentive programs. Prior to this he was Head of Research, also at ABB Aros Securities. Per received his M.Sc. in engineering from the Institute of Technology in Linköping, Sweden.
Robert Tansley is a Partner at Cambridge Innovation Capital. After 7 years working in hospital medicine, Robert worked in development and regulatory roles at Sanofi, the MHRA, and Roche before spending a decade working in early-stage biotech companies including being involved in three start-up companies including two as CEO. Robert joined CIC in 2014 focusing on life science investments in companies based on innovative science.
Reetika Bhardwaj is an Associate at ARCH Venture Partners. Reetika is a biochemist by training and combines her subject matter expertise with experiences in healthcare consulting, investment banking, and corporate strategy. She has authored 5 peer-reviewed publications with greater than 100 citations in the areas of immunology, oncology, neuroscience, and intracellular signalling.
Prior to ARCH, Reetika worked in healthcare consulting as a scientific advisor at Spectrum Science, working with a wide range of biotech and pharma companies on corporate strategy, product positioning, market research, and business development. Most recently she also worked with the University of Chicago Innovation Fund, a seed-stage fund that invests in scientific spinouts from the University of Chicago and Argonne National Lab.
Reetika holds a B.S. in biomedical sciences from University of Delhi (she was ranked #1 nationally), a Ph.D. in biochemistry and molecular biology from Virginia Commonwealth University, and an MBA from the University of Chicago Booth School of Business.
Cindy Phan is an Associate Scientist at Pretzel Therapeutics. She received her B.S. in chemistry from Lund University and M.S. in chemistry from the University of Gothenburg in Sweden.
Maria Falkenberg is Professor of Medical Biochemistry at the Sahlgrenska Academy of the University of Gothenburg, Sweden, where her group researches human mitochondrial DNA replication.
Maria has been awarded the Fernströms prize (2009), the Sven and Ebba-Christina Hagberg prize (2010), and the Edlunska Prize (2012), and was nominated to the Royal Swedish Academy of Sciences in 2015.
Maria earned her Ph.D. from the University of Gothenburg in both the Per Elias group in Gothenburg and the Robert Lehman group at Stanford University. During her postdoctoral fellowship, she studied the mechanisms of mitochondrial DNA replication in the Nils-Göran Larsson Laboratory at the Karolinska Institute.
Jay Parrish is Chairman and Chief Executive Officer of Pretzel Therapeutics. He is also a Venture Partner at ARCH Venture Partners and co-founder of ROME Therapeutics. Jay most recently co-founded and served as the Chief Business Officer of Vir Biotechnology, where he helped lead the company as its first employee through its IPO and first drug approval.
Jay is an accomplished scientist who began his career at Gilead Sciences, Inc. in the Medicinal Chemistry group, where his research focused on the discovery of small molecule antivirals. He was a co-inventor of ledipasvir (Harvoni®) and remdesivir (Veklury®). After nearly a decade in research, he joined Gilead’s Corporate Development team, ultimately leading infectious disease business development for the company. Jay has authored over 25 peer-reviewed scientific publications and holds over 30 issued patents and applications.
Jay received his B.S. in chemistry from Emory University, a Ph.D. in synthetic organic chemistry from the University of South Florida and an MBA from the University of California, Berkeley Haas School of Business.
Michelle McElroy is Manager of Operations at Pretzel Therapeutics. Michelle’s diverse and creative skill set supports Pretzel’s Business Operations as well as the Research & Development team. Prior to joining Pretzel, Michelle was an Executive Assistant at McKinsey & Company for four years. She is an alumna of Berklee College of Music, where she studied music business and management.
Sir Doug Turnbull is one of the world's foremost experts in mitochondrial disease. He is currently the Professor of Neurology and previously Director of the Wellcome Centre for Mitochondrial Research at Newcastle University until his retirement in 2021. He developed and led the NHS National Highly Specialized Services for Rare Mitochondrial Diseases of Children and Adults, and was Director of the Newcastle University / MRC Centre for Ageing and Vitality. He was also an Honorary Consultant Neurologist at Newcastle Hospitals NHS Foundation Trust, an NIHR Senior Fellow, and has chaired Wellcome Trust panels and committees.
His research has focused on the role of mitochondria in health and disease. He has made seminal contributions to understanding the etiology of mitochondrial DNA disease and was a pioneer in the development of mitochondrial donation.
Doug’s honors include a knighthood in 2016, a Fellowship to the Royal Society in 2019, and the Buchanan Medal in 2020.
Doug trained as a neurologist, earning his M.D. and Ph.D. degrees from Newcastle University.
Julia Sullivan is an Executive Assistant at Pretzel Therapeutics. She began her career as an Executive and Personal Assistant in the entertainment industry. Prior to joining Pretzel, Julia was an Executive Assistant at McKinsey & Company for five years. She earned a BFA in dramatic writing from the Tisch School of the Arts at New York University.
Fred H. Gage has been President of the Salk Institute since 2019, where he has been a member of the faculty since 1995. He is a professor in the Laboratory of Genetics and holds the Vi and John Adler Chair for Research on Age-Related Neurodegenerative Disease.
Fred’s research concentrates on the plasticity, adaptability, and diversity observed in the brain. His most seminal work showed that, contrary to accepted dogma, the creation of new neurons occurs in the adult human brain.
Fred’s lab currently models diseases in the laboratory using human stem cells. By reprogramming human skin cells and other cells from patients with neurologic and psychiatric diseases into induced pluripotent stem cells and induced neurons, his work is deciphering the progression and mechanisms that lead to disorders including Alzheimer’s disease, Parkinson’s disease, bipolar disease, schizophrenia, depression, and autism.
Fred is a fellow of the National Academy of Sciences, the National Academy of Medicine, the American Academy of Arts and Sciences, and the American Philosophical Society. He is the recipient of numerous awards including the Keio Medical Science Prize, the Christopher Reeve Research Medal, and the inaugural International Society for Stem Cell Research Achievement Award in 2020.
Fred received his B.S. from the University of Florida and his M.S. and Ph.D. degrees from Johns Hopkins University.
Andrew Griffin is Vice President, Chemistry at Pretzel Therapeutics. After working for twelve years in the medicinal chemistry department at the AstraZeneca Neuroscience Research Centre in Montréal, where he held the position of Associate Director, he joined the NEOMED research center in Montréal and then moved into independent drug discovery consultancy. As a consultant, Andrew worked with several Montréal based and Boston based organizations, including Praxis Precision Medicines. Andrew joined the Pretzel Therapeutics team in 2020. He earned his Ph.D. in chemistry in the lab of Tim Gallagher at the University of Bristol and completed postdoctoral research in the lab of Stephen Hanessian at the Université de Montréal.
We owe our formation to the visionary leadership of Paul Thurk, managing director with ARCH Venture Partners, who passed away in 2021. He developed and advised numerous companies in the healthcare industry on a national and global scale. Paul touched many lives and left an indelible impact on the biotech industry over the course of his career.
Jeremy Green is Senior Vice President of Research at Pretzel Therapeutics. Jeremy has broad experience in medicinal chemistry, including drug design and synthesis, analytical, scale-up, and early development. His experience includes over 20 years at Vertex Pharmaceuticals, where he held roles of increasing responsibility and leadership in the medicinal chemistry group. Jeremy was also a medicinal chemist at Ariad Pharmaceuticals and a development chemist at Marion Merrell Dow.
He received his B.S. in chemistry from the University of Manchester and Ph.D. in organic chemistry from University of Edinburgh. Jeremy completed postdoctoral studies at the University of Wisconsin-Madison, where he applied structure-based design to discover protease inhibitors.
Sean Jesinkey is Director of Corporate Development at Pretzel Therapeutics. He brings professional experience in drug discovery science, biotech equity research and biopharma deal making. Sean received both his PharmD and Ph.D. from the Medical University of South Carolina and his MBA from the Darla Moore School of Business at the University of South Carolina. Sean was also a Postdoctoral Fellow at the Yale School of Medicine where his research focused on unlocking the biology of a rare mitochondrial disease.
Mattias Stamgren is an Associate Scientist at Pretzel Therapeutics. He earned his M.S. in molecular biology from the University of Gothenburg.
Howard Levy is a Senior Clinical Advisor at Pretzel Therapeutics. He has over 20 years of experience in the pharmaceutical industry, including positions as Chief Medical Officer at Catalyst Biosciences, Ampio Pharmaceuticals, Inspiration Biopharmaceuticals, and Sangart. He also advised on the clinical development and approvals of Xigris (activated protein C), Ixinity (Factor IX), Obizur (porcine Factor VIII), and Afstyla (Factor VIII). Howard earned his MBBS, M.B., B.Ch., and Ph.D. at the University of the Witwatersrand in Johannesburg, South Africa.
Noa Rotem-Warner is Associate Director of Operations at Pretzel Therapeutics. She previously served as Executive Assistant at Foundation Medicine and McKinsey & Company. Noa earned her B.A. in communications and international relations from The Hebrew University of Jerusalem.
Paolo Di Giorgio is the Chief Executive Officer and Managing Director of Angelini Ventures, the corporate venture arm of Angelini Industries. Along with Pretzel Therapeutics, the fund’s recent investments include participation in Argobio, a European start-up studio and the co-founding of the Angelini Lumira Bioscience Fund, a fund that invests in early stage CNS companies in North America.
Paolo is a life sciences executive with over 15 years of experience in venture capital, R&D, external innovation and business development at Merck, Novartis and Angelini Pharma. Originally a neuroscientist by training, he has led global teams on several projects in different therapeutic areas such as neuroscience, pain, rare diseases, anti-infectives, oncology, and metabolic disorders.
During his Ph.D. and postdoctoral studies at Harvard University and at the Salk Institute for Biological Studies, Paolo pioneered a novel method to study neurodegenerative diseases using stem cell-derived neurons. Paolo has also completed an executive MBA program at IE Business School in Madrid, Spain.
Cheryl Calhoun is Vice President & Head of Global Operations at Pretzel Therapeutics. She has over 20 years of experience working with early-stage biotech companies, including positions as Director of Global Contracts for Thermo Fisher’s Viral Vector and Advanced Therapy divisions, Head of Business Operations at Tilos Therapeutics, and Vice President of Corporate Development at Xcovery. Cheryl earned her B.A. in economics from New York University and her MBA from the University of Illinois.
Javier Miralles Fusté is a Scientist at Pretzel Therapeutics. He studied biology at Universtitat de Barcelona and then moved to Sweden to earn his Ph.D. from Karolinska Institutet in the lab of Maria Falkenberg. Javier conducted his postdoctoral research at the Salk Institute in the lab of Jan Karlseder.
Simon Giroux is Vice President of Chemistry at Pretzel Therapeutics. He began his career at Vertex Pharmaceuticals in 2009 where he was involved in various programs toward anti-infective, oncology, neurology, and pulmonary disease indications. Simon joined Pretzel Therapeutics as Vice President, Chemistry in March 2022. He obtained his Ph.D. from the University of Montreal under the guidance of Stephen Hanessian where he completed the total synthesis of the natural product borrelidin. In 2007, Simon moved to Harvard University as an NSERC postdoctoral under the guidance of Nobel Laureate E.J. Corey, where he completed the total synthesis of the steroid dafachronic acid A.
Johanna Lönnermark is an Associate Scientist at Pretzel Therapeutics. Previously, she worked as an engineer at Sahlgrenska University Hospital sequencing whole genome libraries. She earned her M.S. in biotechnology from Chalmers University of Technology in Gothenburg, Sweden.
Nils-Göran Larsson is professor of mitochondrial genetics at the Department of Medical Biochemistry and Biophysics at Karolinska Institutet. He has specialized in mitochondrial biology for more than 25 years. Nils is also a pediatrician and a senior consultant at the Center for Inherited Metabolic Diseases at the Karolinska university hospital. He has published over 150 articles on mitochondrial biology, including features in Nature, Cell, Cell Metabolism, and the Annual Review of Biochemistry. Nils is a member of the Swedish Royal Academy of Sciences and EMBO. He holds an M.D. and a Ph.D. in mitochondrial genetics from the University of Gothenburg.
Nuha Svensson, Manger, Operations at Pretzel Therapeutics in Sweden, has over 25 years of experience in new start-up operations, project management, and in supporting executives and CEO’s across different industries. Recently, Nuha served as an Executive Assistant at Getinge AB supporting the executive management within the HR & Sustainability, Legal Compliance & Governance and Research & Business Development teams. Additionally, she has acted as the facility/office manager for Getinge HQ office.
Nuha earned her Diploma in Economics and Marketing at Lund University and her degree in Administration Technology at Gothenburg University.
Gunther Kern is Senior Vice President, Biology and Biochemistry at Pretzel Therapeutics. He has over 25 years of experience in drug discovery within large pharma as well as biotech companies. Gunther also worked as a consultant for over 8 years to help small to medium biotech companies establish a successful research and business. His previous appointment was with C4 Therapeutics, a company that focuses on protein degraders, before joining Pretzel Therapeutics in 2020. Gunther holds a Ph.D. in biochemistry from the University of Regensburg in Germany and an MBA from the University of Wilmington in Delaware.
Viktor Posse is a Scientist of Biology at Pretzel Therapeutics. He obtained his undergraduate degree at the University of Gothenburg, studying pharmacology and biochemistry. Viktor also earned a Ph.D. from the University of Gothenburg under the supervision of Claes Gustafsson. His thesis focused on mitochondrial transcription and its role in DNA replication.
Paul Charifson is a Senior Research Advisor at Pretzel Therapeutics. He currently also serves as a Senior Therapeutics Scientist in the Therapeutics Translator at Harvard Medical School and Drug Discovery Consultant at Golden Road Consulting, LLC. Paul previously worked as a Senior Research Fellow of Medicinal Chemistry at Vertex Pharmaceuticals for 20 years and at Glaxo-Wellcome for 7 years prior to that. He holds a B.S. in pharmacy from the University of Rhode Island and a Ph.D. in medicinal chemistry from the University of North Carolina at Chapel Hill, where he additionally completed a postdoctoral fellowship in theoretical chemistry. He has contributed to over 60 peer-reviewed scientific articles and over 60 issued US patents and has led projects in multiple therapeutic areas that successfully resulted in pre-clinical candidates.
Jeff Saunders is a Senior Research Advisor at Pretzel Therapeutics. He currently serves as Senior Vice President of Drug Discovery at Casma Therapeutics. Jeff previously was Vice President of Chemistry at Nuvalent, co-founder of Resilience Therapeutics, Inc., Vice President of Small Molecule Drug Discovery at Ember and Vice President of Chemistry at Agios. He holds a B.A. in chemistry from Hope College and a Ph.D. in chemistry from the University of South Carolina, after which he completed an NIH postdoctoral fellowship at the University of Pennsylvania.
Pretzel is supported by a group of distinguished global investors who share our mission of developing groundbreaking therapies for patients who suffer from devastating diseases of mitochondrial dysfunction.