Our Leadership

Mr Paterson joined Verastem Oncology in 2011 and was its President and Chief Operating Officer prior to becoming President and Chief Executive Officer in 2023. He has more than 30 years of experience at healthcare and biotechnology companies, including leadership roles as Chief Business Officer (CBO), Chief Operating Officer (COO) and Chief Executive Officer (CEO), with specific expertise in oncology drug and diagnostic product development, business development, and launch planning. Mr Paterson was the co-founder and COO of On-Q-ity, a developer of technology to capture and analyze circulating tumor cells, and the founding CEO of The DNA Repair Company (merged to form On-Q-ity), which developed oncology-focused molecular diagnostics. Prior to that, Mr Paterson was Head of Global Strategy for Specialty Market and Patient-Level Data at IMS Health, after playing a key role in the acquisition of PharMetrics by IMS Health as VP, Marketing and Corporate Development. While at PharMetrics, Mr Paterson led the development of an innovative suite of pharmaceutical product launch tools that became the basis of the company’s product line. Earlier in his career, Mr Paterson led clinical development and regulatory initiatives in academic, industry, and CRO organizations. Mr Paterson holds a BA in biology from Boston University, and attended the Northeastern University Graduate Pharmacology program.

Mr Calkins was appointed Chief Financial Officer in October, 2023. He joined Verastem Oncology in 2018 and served as the Vice President of Finance prior to becoming CFO. He has 14 years of finance and accounting experience and has been instrumental in the Company’s strategic transformation. Prior to joining Verastem, he was a Technical Accounting Consultant at CFGI where he advised companies across a variety of industries on technical accounting issues, financial statement preparation and initial public offering readiness, and internal controls. Mr. Calkins began his career at PwC, LLP in Boston within the Assurance practice. He received his Bachelor of Science in Accounting from Bryant University and his Master of Science in Accounting from Northeastern University.

Ms Carew has been with Verastem Oncology since 2012, bringing nearly 20 years of management and consulting experience in the biopharma industry, assisting companies in transition from research stage to development stage to commercial stage. Most recently, she served as the part-time Head of Human Resources at Verastem Oncology, while also consulting with other development and clinical stage therapeutic companies, including Dicerna Pharmaceuticals, Catamaran Bio, Aquinnah Pharma and OvaScience.

Mr. Crowther is an accomplished marketing and commercialization leader with more than 20 years of experience leading commercial, marketing and business operations and launching more than 10 leading oncology therapies in multiple geographies, including the U.S., Europe and emerging markets. Mr. Crowther joined Verastem in October of 2023 and serves as our Chief Commercial and Strategy Officer. He was most recently the Chief Business Officer at Minerva Biotechnologies, leading business results in immunotherapies for cancer treatment and executive leader for strategic planning, business development, and commercial operations.Before, Mr. Crowther was the Interim U.S. Lead and Vice President of U.S. Marketing at Kite Pharma where he was responsible for strategic marketing and business operations. Prior to Kite Pharma, he was in positions of increasing responsibility within Global Marketing at Celgene and he led commercial strategy and execution across several therapeutic areas and launched 10 oncology products, including Velcade, Xgeva, Istodax, Revlimid, Onureg, Inrebic, Reblozyl, Yescarta and Tecartus. He received his Bachelor of Science (BS) at the Manchester Metropolitan University in Manchester, United Kingdom.

Dr. Hayslip joined Verastem Oncology as the Chief Medical Officer in April 2024. Dr. Hayslip has more than 25 years of oncology and research and development experience across industry and academia, most recently serving as the chief medical officer at I-MAB Biopharma. Prior to that, Dr. Hayslip was the vice president of clinical development at Nektar Therapeutics and led clinical development activities for multiple therapies while at AbbVie Oncology. Prior to joining AbbVie Oncology, Dr. Hayslip led numerous cancer research studies while at the University of Kentucky’s Markey Cancer Center. Dr. Hayslip served as the chief of hematology and bone marrow transplant and the director of clinical research and data management at the University of Kentucky’s Markey Cancer Center, where he led numerous cancer research studies. Dr. Hayslip received his medical degree from Northeast Ohio Medical University and a master’s degree in clinical research from the Medical University of South Carolina. Following his residency in internal medicine, Dr. Hayslip completed his fellowship in hematology-oncology at the Medical University of South Carolina, leading to dual board certifications in both hematology and medical oncology. Dr. Hayslip holds multiple U.S. and international patents and has published dozens of scientific papers and reviews in renowned journals including Lancet Haematology, Clinical Cancer Research, Leukemia Research, Blood, and Journal of Clinical Oncology.

Dr Pachter brings over 30 years of experience in leading discovery and translational research for small molecule and monoclonal antibody anti-cancer therapeutics. He was previously Head of Cancer Biology at OSI Pharmaceuticals, where his team was responsible for development of models of tumor cell EMT (epithelial-mesenchymal transition) and discovery of drugs disrupting this process. At OSI, he advanced five small molecules into development for treatment of cancer, including OSI-906—a selective IGF-1R/insulin receptor kinase inhibitor which progressed to phase 3 clinical trials—and OSI-027, a selective mTOR kinase inhibitor. Prior to OSI, Dr Pachter held positions of increasing responsibility at Schering-Plough, where he progressed three agents into development including the monoclonal antibody robatumumab, which advanced to phase 2 clinical evaluation in cancer patients. Dr Pachter also made key contributions to the regulatory approval of temozolomide for treatment of glioblastoma. He is an author of over 50 peer-reviewed publications and inventor on numerous patents. Dr Pachter did his postdoctoral work in pharmacology at Yale University School of Medicine and he holds a PhD from Baylor College of Medicine.

Ms. Mockbee joins Verastem as the Global Head of Regulatory Affairs and Development and brings more than 25 years of drug development experience in the pharmaceutical and biotech industry with expertise in clinical development and regulatory strategy. Before her role at Verastem, she was the Chief Development Officer and Senior Vice President of Regulatory at OncXerna Therapeutics. Ms. Mockbee established her distinguished career at Eli Lilly and Company, where she spent 20 years in oncology drug development in various leadership positions. Ms. Mockbee led the Verzenio global development program, where she combined innovation with speed to create and execute a development strategy that led to Verzenio’s approval and launch for metastatic breast cancer as well as the first positive Phase 3 study (monarchE) in early breast cancer for a CDK 4 & 6 inhibitor. Prior to that, Ms. Mockbee was the Head of Global Regulatory for Lilly Oncology where she was instrumental in original and supplemental NDA/BLA submissions and approvals for Gemzar, Alimta, Erbitux, and Cyramza, in addition to providing regulatory direction for the overall oncology portfolio. Ms. Mockbee holds Bachelor of Science degrees in Chemistry and Pharmacy from Butler University and an MBA from Purdue’s Krannert School of Business.

Mr. Ros brings more than 35 years of commercialization and operational experience in the biopharmaceutical industry with a track record of capital-driving success at publicly traded biopharmaceutical companies undergoing evolutions from early stage to registrational development. Mr. Ros joined Verastem in January 2025 as the chief operating officer. Before, Mr. Ros served as chief executive officer and board director at FORE Biotherapeutics an early, clinical-stage oncology company focused on recurrent CNS malignancies. Previously, Mr. Ros held executive leadership roles at prominent biopharmaceutical companies, including Epizyme, Sanofi-Genzyme, and ARIAD Pharmaceuticals, where he built fully integrated commercial organizations, delivered strategic collaborations, secured multiple FDA approvals, and supported successful launches. Mr. Ros began his career at Bristol-Myers Squibb where he held positions of increasing responsibility within its Oncology division, contributing to and championing the successful launches of many leading oncology brands. In addition to his executive experience, Mr. Ros serves as a board member at Cogent Biosciences, contributing to its Audit, Nomination, and Governance Committees, and previously served on the Board of Trustees of CancerCARE. Mr. Ros earned a Bachelor of Science in Business Administration from SUNY Plattsburgh.

Mr. Sanburn is an accomplished scientific and business leader with nearly 30 years of experience across R&D, portfolio strategy, and business development and collaborations. Mr. Sanburn joined Verastem in February 2022 and serves as the Chief Business Officer. Previously, Mr. Sanburn was the Senior Vice President of Corporate Development and External Engagement, where he had responsibility across the portfolio for business development, alliance management, clinical operations and field medical. In this role, Mr. Sanburn was instrumental in expanding sole rights to avutometinib, including EU and Japan, leading Verastem to be the first recipient of the PanCan Therapeutic Accelerator Award and executing the discovery and development agreement with GenFleet for up to three RAS-pathway related programs. Before, Mr. Sanburn was with Eli Lilly and Company for more than 20 years where he served in scientific and business leadership roles for portfolio-changing transactions, including Imclone and Loxo Oncology, in-licensing and out-licensing key programs, developing R&D collaborations and owning clinical trial agreements with leading pharmaceutical and biotech companies. Prior to Eli Lilly, Mr. Sanburn helped set up the National Gene Vector Laboratory at Indiana University Medical Center, which was fundamental to early clinical gene therapies. Mr. Sanburn received his undergraduate degree from Indiana University and his graduate degree from Purdue University.

Dr Kauffman has over 25 years of experience in the life sciences industry, including expertise in preclinical research, clinical development and regulatory strategy. He currently serves as chief executive officer (CEO), president and board member of Nereid Therapeutics Inc. In addition to Verastem Oncology and Nereid, he is a board member for Adicet Bio, Kezar Life Sciences, Incendia Therapeutics and BiVictriX Therapeutics. Previously, Dr Kauffman served as the co-founder and CEO of Karyopharm, where he guided the Company’s transition from a discovery stage biotechnology company to a commercial stage organization and the global approvals of XPOVIO(r). Prior to joining Karyopharm, Dr Kauffman was CMO of Onyx Pharma, where he led the development of Kyprolis(r) following the Onyx acquisition of Proteolix Inc., where he served as board member and then CMO. Previously, Dr. Kauffman was President and Chief Executive officer of EPIX Pharmaceuticals, Inc. (previously Predix Pharmaceuticals, Inc.). Before that, he was the leader of the Velcade(r) development program at Millennium Pharmaceuticals, and has also held a number of senior positions at Millennium Predictive Medicine and Biogen. Dr Kauffman received his MD and PhD from Johns Hopkins Medical School, trained in Internal Medicine at Beth Israel (Deaconess) Medical Center and in Rheumatology at Massachusetts General Hospital, and is board certified in Internal Medicine.

Dr Bunn is a Distinguished Professor of Medicine and James Dudley Chair in Cancer Research, Division of Medical Oncology at the University of Colorado School of Medicine. Dr Bunn previously served as section head of the US National Cancer Institute (NCI)-Navy Medical Oncology branch, Head of the Division of Medical Oncology at the University of Colorado and Director of the University of Colorado Cancer Center. Dr Bunn was President of the American Society of Clinical Oncology (ASCO), as well as on its Board of Directors. He was also President of the American Association of Cancer Institutes (AACI) and has chaired the US Food and Drug Administration’s Oncologic Drugs Advisory Committee. Dr Bunn served on the Board of Directors, as president and as CEO, of the International Association for the Study of Lung Cancer (IASLC), growing the IASLC to become a highly impactful, multidisciplinary organization that includes researchers and clinicians from all over the world. Dr Bunn was also the Principal Investigator on the Specialized Program in Research Excellence in Lung Cancer (SPORE) grant funded by NCI to expand understanding about the biology of the disease, as well as to find new methods of diagnosis, prevention, and treatment. The author of hundreds of articles, reviews and book chapters, Dr Bunn’s work is credited with setting standards in the treatment of the disease.

Mr Gagnon has more than 20 years of business, commercial and global financial operations experience and currently serves as Chief Financial Officer of Remix Therapeutics, a privately held biotechnology company developing therapies to modulate RNA processing and address the drivers of many disease states. Prior to that, Mr. Gagnon was Chief Financial Officer / Operating Partner of Gurnet Point Capital, a healthcare venture capital and private equity fund, and previously Chief Financial Officer of Verastem Oncology. Before joining Verastem in 2018, Mr Gagnon served as the Chief Financial Officer at Harvard Bioscience, Inc, Executive Vice President, Chief Financial Officer and Treasurer at Clean Harbors, Inc., as well as Chief Accounting Officer and Controller at Biogen Idec, Inc. Earlier, he worked in a variety of senior positions at Deloitte & Touche, LLP, and Price Waterhouse Coopers, LLP. Mr Gagnon holds an M.B.A. degree from the MIT Sloan School of Management and a B.A in accounting from Bentley College.

Mr. Kapur is a deeply experienced executive with over 25 years of experience in pharmaceutical and biotech companies across U.S. and international markets. He has held senior leadership positions where he has been responsible for launching significant global brands, building and managing commercial capabilities in small and large organizations, driving corporate strategy, and managing alliances. Mr. Kapur is currently a member of the Board of Directors for Nurix Therapeutics. Most recently, he served as the Executive Vice President, Corporate Strategy and Chief Commercial Officer at Geron Corporation. Before Geron, Mr. Kapur served as the Chief Commercial Officer at Actinium Pharmaceuticals, Inc. and as the Vice President, Head of Early Assets, Biomarkers and External Innovation for Worldwide Oncology Commercialization at Bristol-Myers Squibb. Previously, Mr. Kapur was Vice President, Global Head of Commercial and Portfolio Strategy at Baxalta, Inc., which was acquired by Shire PLC in 2016. Before joining Baxalta, Mr. Kapur served as the Vice President, Commercial Leader Hematology Franchise at Johnson & Johnson’s global pharmaceutical strategy organization and in various sales and marketing leadership roles. Mr. Kapur holds a BE from Birla Institute of Technology in India, an MS in Industrial Engineering from Louisiana Tech University, and an MBA from the Fuqua School of Business at Duke University.

Mr. Johnson is a recognized leader in the pharmaceutical and biotechnology industry, with more than three decades of experience, currently serving as Chief Executive Officer and Board Director of Reaction Biology. He served as the Company Group Chairman of Biopharmaceuticals within Johnson & Johnson, responsible for the Biotechnology, Immunology, and Oncology commercial businesses. Previously, Mr. Johnson served as president of Eli Lilly & Company’s Worldwide Oncology Unit, following the company’s 2008 acquisition of ImClone Systems, Inc., where he served as Chief Executive Officer and a member of ImClone’s Board of Directors. He has served as a member of the Board of Directors of Pharmaceutical Research and Manufacturers of America (PhRMA) and as a member of the Health Section Governing Board of biotechnology Industry Organization (BIO). Mr. Johnson also served as Chairman, President, and Chief Executive Officer of Dendreon Corporation, and has held other executive roles within the biotech industry. Currently, he is a member of the Board of Directors of Xeris Biopharma Holdings, Inc (XERS) and Axogen, Inc (AXGN).

Mr Paterson joined Verastem Oncology in 2011 and was its President and Chief Operating Officer prior to becoming President and Chief Executive Officer in 2023. He has more than 30 years of experience at healthcare and biotechnology companies, including leadership roles as Chief Business Officer (CBO), Chief Operating Officer (COO) and Chief Executive Officer (CEO), with specific expertise in oncology drug and diagnostic product development, business development, and launch planning. Mr Paterson was the co-founder and COO of On-Q-ity, a developer of technology to capture and analyze circulating tumor cells, and the founding CEO of The DNA Repair Company (merged to form On-Q-ity), which developed oncology-focused molecular diagnostics. Prior to that, Mr Paterson was Head of Global Strategy for Specialty Market and Patient-Level Data at IMS Health, after playing a key role in the acquisition of PharMetrics by IMS Health as VP, Marketing and Corporate Development. While at PharMetrics, Mr Paterson led the development of an innovative suite of pharmaceutical product launch tools that became the basis of the company’s product line. Earlier in his career, Mr Paterson led clinical development and regulatory initiatives in academic, industry, and CRO organizations. Mr Paterson holds a BA in biology from Boston University, and attended the Northeastern University Graduate Pharmacology program.

Ms Robertson is the Executive Vice President and Chief Financial Officer of Geron Corporation. Prior to joining Geron Corporation, she served as the Chief Financial Officer of Editas Medicine, a CRISPR genome editing company, where she raised $500M in capital to support the company’s research transition into late-stage clinical development. Before that, she served as Chief Financial Officer of Momenta Pharmaceuticals, from 2018 until 2020, leading the finance team through a strategic restructure, before its acquisition by Johnson & Johnson. Prior to joining Momenta, Ms Robertson held multiple commercial finance roles of increasing responsibility, including Vice President, Oncology Finance for Baxalta following its spin-off from Baxter International where she worked on the acquisition and commercialization of their first oncology drug, Oncaspar and Head of Financial Planning and Analysis and Operations Excellence at Ironwood Pharmaceuticals, positioning the finance organization to support the commercial launch of Linzess. Before that, for 16 years, she held various finance and commercial operations roles at Genzyme Corporation (now Sanofi Genzyme) where she led the integration of several acquired Oncology assets, subsequently leading the buildout of the Commercial operations team to support five global commercial products. Ms Robertson received her B.S. in Finance and A.S. in Accounting and Management from Bentley University.

Dr. Rowinsky’s professional focus has been on the clinical and registrational strategies of anticancer therapeutics. Currently, Dr. Rowinsky serves as a Director and President at Inspirna, Inc (formerly RGenix, Inc,) a life sciences company focused on discovering new cancer targets using a novel microRNA platform licensed. He served as a Consulting Chief Medical Officer for Hummingbird Biosciences, which has a novel platform for the unique epitope targeting of monoclonal antibodies from February 2020 to March 2023, and also served as the Chief Scientific Officer of Clearpath Development Co, which rapidly advanced development-stage therapeutic assets to pre-defined human proof-of-concept milestones. Prior to serving in these capacities, he was the Head of Research and Development, Chief Medical Officer, and Executive Vice President of Stemline Therapeutics (2010-2015). In 2010, Dr. Rowinsky co-founded Primrose Therapeutics and became its Chief Executive Officer until it was acquired in 2011. From 2005 to 2010, he served as the Chief Medical Officer and Executive Vice President of Clinical Development and Regulatory Affairs of ImClone Systems Incorporated, a life sciences company focused on monoclonal antibodies, which was acquired by Eli Lilly. Before that, Dr. Rowinsky held several positions at the Cancer Therapy and Research Center’s Institute of Drug Development, including Director of the Institute and SBC Endowed Chair for Early Drug Development. Prior to that, he served as Clinical Professor of Medicine in the Division of Medical Oncology at the University of Texas Health Science Center at San Antonio and as Associate Professor of Oncology at the Johns Hopkins University School of Medicine. Dr. Rowinsky is a member of the Board of Directors of Biogen and Purple Biotech, all public life sciences companies, and has served on the Board of Directors of BIND Therapeutics, a life sciences company acquired by Pfizer, and Navidea Biopharmaceuticals, Inc. He played an integral role in the development and execution of clinical development and registrational strategies resulting in the approval of a wide array of classical cytotoxics, monoclonal antibodies, and targeted therapeutics worldwide. He has authored more than 310 peer-reviewed manuscripts and serves as an editor of several cancer journals.

Mr Stuglik served as the Chief Executive Officer (CEO) of Verastem Oncology from 2019 through 2023. Mr Stuglik is a global leader in the oncology pharmaceutical sector, having successfully developed, acquired, and launched several important oncology products across multiple tumor types and therapeutic approaches in his more than 30-year career in US and international pharmaceutical development, product strategy, commercialization, and business development. He spent the majority of his career at Eli Lilly and Company, culminating in his role as Global Vice President and Chief Marketing Officer, Oncology Global Marketing, advancing Lilly Oncology from a single approved product to a portfolio of marketed or late-stage compounds across more than 10 cancer types. He was a founding member of Proventus Health Solutions, assisting biotech companies integrate development and commercial considerations into a unified approach. He is a member of the Board of Directors for Verastem Oncology (VSTM), Oncopeptides AB (ONCO), and Puma Biotechnology, Inc (PBYI). Mr Stuglik earned his Bachelor of Science in pharmacy from Purdue University and holds memberships in the American Society of Clinical Oncology, the American Association for Cancer Research, and the International Association for the Study of Lung Cancer.

Dr. Tollefson is the Chief Oncology Medical Officer at Pfizer. Previously, Dr. Tollefson served as the Senior Vice President and Head of Global Medical Affairs at Seagen Inc., where she has led the medical organization through the successful launches of three practice-changing medicines and established a global medical affairs organization. Dr. Tollefson has 30 years of experience in the pharmaceutical industry spending much of her early career at Eli Lilly and Company serving in progressive leadership roles in clinical operations, clinical development, portfolio & program management, and global medical affairs. She supported Lilly’s acquisition and integration of ImClone Systems in 2008 and was part of the Oncology Business Unit Leadership team until her retirement in 2017. During her career sshe has been involved in the launch of eight new medicines and numerous additional indications in the U.S. and international markets, serving patients in over 10 tumor and therapeutic areas. Dr. Tollefson has served on the philanthropic boards of the American Lung Association and the Leukemia and Lymphoma Society Indiana Board of Trustees. She started her undergraduate studies at Kansas State University and earned her Doctor of Pharmacy from the University of Kansas.

Dr Weinberg is a founding member of the Whitehead Institute for Biomedical Research and the Daniel K. Ludwig Professor for Cancer Research in the Department of Biology at MIT. Dr Weinberg is also a founder of Verastem Oncology. Dr Weinberg is the internationally recognized authority on the genetic basis of human cancer development. Dr Weinberg is the author or editor of five books and more than 350 articles. Three of the books are intended for a lay audience: One Renegade Cell, Racing to the Beginning of the Road: The Search for the Origin of Cancer, and Genes and the Biology of Cancer, the latter co-authored with Dr Harold E. Varmus, former Director of the National Institutes of Health. More recently, Dr Weinberg has published the textbook The Biology of Cancer, which is intended for doctoral students learning about this disease. Dr Weinberg is a member of the National Academy of Sciences and the Institute of Medicine, and is a Fellow of the American Academy of Arts and Sciences.

Dr Sznol is Professor of Internal Medicine, Leader of the Melanoma/Renal Cancer Disease-Associated Translational Research Team, and Co-Leader of the Cancer Immunology Program. Dr Sznol is also the current President of the Society for Immunotherapy of Cancer (SITC). He has an international reputation in cancer drug development. Dr Sznol graduated from Rice University and Baylor College of Medicine (BCM) in Houston, Texas. He trained in internal medicine at BCM and completed a medical oncology fellowship in the Department of Neoplastic Diseases, Mount Sinai Hospital, New York. He spent the next twelve years in the Biologics Evaluation Section (BES), Investigational Drug Branch (IDB), Cancer Therapy Evaluation Program of the National Cancer Institute, and was Head of the BES from 1994-1999. He attended on the inpatient units of the Biological Response Modifiers Program, NCI, from 1988-1996 and the Immunotherapy Service of the Surgery Branch, NCI, from 1997-1999. From 1999-2004, he served as Vice President of Clinical Development and Executive Officer of Vion Pharmaceuticals in New Haven, Connecticut.

Dr Der is Sarah Graham Kenan Distinguished Professor at the University of North Carolina at Chapel Hill. Since his initial discovery of RAS oncogenes in human cancer, his research has centered on the study of RAS and RHO oncoproteins in cancer. His research has been funded by grants from the National Cancer Institute, Department of Defense, Lustgarten Foundation, and Pancreatic Cancer Action Network/AACR. He is a member of the NCI RAS Working Group and the Frederick National Laboratory Advisory Committee, and he served previously on the NCI Board of Scientific Counselors. He is currently a member of the Scientific and Medical Advisory Board of the Pancreatic Cancer Action Network and previously on the scientific advisory board of the Lustgarten Foundation. His honors include Fellow of the AAAS, the recipient of an NCI Outstanding Investigator Award, the Battle Distinguished Cancer Research Award, the Mentorship Award for Lifetime Achievement, the University of California, Irvine Distinguished Alumnus Award, and the Einstein BIH Visiting Fellow Award.

He received his PhD from the University of California, Irvine and completed his postdoctoral studies at Harvard Medical School and the Dana-Farber Cancer Institute.