Executive Team

Tim Bertram, PhD

Dr. Bertram has served as Chief Executive Officer of ProKidney since January 2019. Since February 2017, Dr. Bertram has served on the board of directors of NexImmune, Inc. (Nasdaq: NEXI), a clinical-stage biotechnology company developing a novel approach to immunotherapy designed to orchestrate a targeted immune response by directing the function of antigen-specific T cells. Dr. Bertram served as Chief Scientific Officer of Tengion Inc. from 2004 to 2014 after serving as President of Research and Development, where he brought four cell-based therapeutic products from discovery through Phase 2 clinical development. Dr. Bertram was also involved in the development and registration of eight medical products while serving as a senior executive at Pfizer Inc. (NYSE: PFE), SmithKline Beecham Pharmaceuticals, and The Procter & Gamble Company (NYSE: PG) from 1985 to 2004. He was a faculty member at the University of Illinois, and a visiting scientist at the National Institutes of Health. Dr. Bertram received his D.V.M. in Biology and Veterinary Medicine and his Ph.D. in Cellular Pathology from Iowa State University and was board certified in Veterinary Pathology in 1984.

James Coulston, CPA

Mr. Coulston has served as ProKidney’s Chief Financial Officer since January 2022. Prior to that, Mr. Coulston served as ProKidney’s Senior Vice President, Finance from January 2021 to December 2021 and ProKidney’s Vice President, Finance from February 2019 to December 2020. Before joining ProKidney, from August 2015 to January 2019, Mr. Coulston served as the Executive Director, Finance of Banner Life Sciences LLC, a privately held clinical-stage pharmaceutical company combining a proven history of formulation expertise with proprietary technologies to create specialty pharmaceuticals that solve real unmet clinical needs, where Mr. Coulston oversaw the financial, human resources, and IT activities. From 2007 to 2015, Mr. Coulston held finance roles of increasing responsibility at Targacept Inc. (Nasdaq: TRGT), a clinical-stage biopharmaceutical company developing novel NNR Therapeutics™ before it merged with and into Catalyst Biosciences, Inc. (Nasdaq: CBIO), a clinical-stage biopharmaceutical company focused on creating and developing novel medicines to address serious medical conditions, including Senior Director, Finance and Controller. Mr. Coulston earned his B.S. and master’s degree in accounting from North Carolina State University and is a Certified Public Accountant in the state of North Carolina.

Todd C. Girolamo, JD, MBA

Mr. Girolamo joined ProKidney as Chief Legal Officer in March 2022. Prior to that, he spent 11 years at Caladrius Biosciences, Inc. (Nasdaq: CLBS), where he served as Chief Legal Officer, Senior Vice President of Corporate Development and Corporate Secretary. He began his legal career at Cahill Gordon & Reindel in 1990 and later at Reid & Priest, practicing in the areas of securities law, intellectual property, employment law and general commercial litigation. After private practice, Mr. Girolamo spent 12 years on Wall Street in institutional equities as a series 24, 7 and 63 licensed principal at Oppenheimer & Co., CIBC World Markets, Leerink Swann (now SVB Securities LLC) and Summer Street Research Partners where he specialized in equity research, sales, and trading of biotechnology, pharmaceuticals and medical technology market sectors. Mr. Girolamo then served as an analyst and portfolio manager at Lion’s Path Capital managing a long-short portfolio of biopharma and med-tech equities. Mr. Girolamo received an A.B. with honors from Harvard College, a J.D. from the University of Pennsylvania Law School and an MBA from Columbia Business School.

Deepak Jain, PhD

Dr. Jain has served as ProKidney’s Chief Operating Officer since March 2016. Dr. Jain brings over 36 years of experience in the development of tissue-engineered and cell therapy products. Previously, Dr. Jain held management roles of increasing responsibility at Johnson & Johnson (NYSE: JNJ) and Merck (NYSE: MRK) and was involved in the development of four marketed products including Johnson & Johnson’s erythropoietin-based drug Eprex (epoetin alfa). Dr. Jain has served as Chairman of the American Society for Testing and Materials Task Group on Preservation of Cells and Tissue Engineered Medical Product’s with Cells and has served as Chairman of the USP Tissue and Tissue-based Products Ad hoc Advisory Panel and was member of the USP Biologics and Biotechnology Cell, Gene and Tissue Therapy Expert Committee. Dr. Jain received his B. Tech and M. Tech in Chemical Engineering and his Ph.D. in Biochemical Engineering from the Indian Institute of Technology in Delhi, India.

Darin J. Weber, PhD

Dr. Weber joined ProKidney as Senior Vice President of Regulatory Development in September 2020, and was promoted to Chief Regulatory Officer, SVP and Head of Global Regulatory Affairs, Quality Management, Biometrics and Market Access. He is responsible for leading the development and implementation of ProKidney’s regulatory strategy in all markets, worldwide, interfacing with regulatory authorities and oversight of quality management, market access, pricing and reimbursement. Dr. Weber has over 25 years of experience in cellular and tissue-based regenerative medicine products, with previous roles as Senior Vice President of Regulatory and Quality at Medeor Therapeutics, from February 2016 to December 2019; Executive Vice President of Global Regulatory Affairs and Quality Management at Mesoblast, from June 2011 to February 2016; Senior Consultant for Cell and Gene Therapies at Biologics Consulting Group from February 2004 to May 2011, and positions of increasing responsibility at the FDA’s Center for Biologics Evaluation and Research, including as Chief of Cellular Therapies Branch in the Office of Cellular, Tissues and Gene Therapies, (now known as the Office of Tissues and Advanced Therapies) from September 1996 to January 2004. He is a long-serving member of United States Pharmacopeia (USP) expert committees for human tissues and advanced therapies. Dr. Weber received his B.S. in Molecular Biology from The Evergreen State College and a Ph.D. in Biochemistry and Biophysics from Oregon State University.

Mary Weger

Ms. Weger has an extensive and accomplished background in human resources, especially for emerging early-stage companies as well as established innovative biopharmaceutical companies. Prior to working with emerging biopharmaceutical companies, Ms. Weger spent more than ten years at Celgene Corporation as Celgene’s first Chief Human Resource Officer (CHRO) joining early in the company’s maturation with just one compound and 120 employees. Mary was instrumental in Celgene’s growth globally over her tenure building Celgene’s organizational capability throughout 85 countries, three acquisitions and through five marketing approvals. Mary also held CHRO positions in subsequent organizations. Most recently, she was principal of PPC Solutions, an HR consulting firm focused on building organizational capability in early-stage life science companies as well as the HR function of biotechnology start-ups including VectivBio, Therachon, Autolus, In8Bio and NexImmune. Ms. Weger previously served first as Senior Vice President (SVP), HR, then Chief Performance Officer at Aegerion Pharmaceuticals where she was responsible for HR strategy, corporate productivity and led the Company through a period of rapid growth during which was recognized in the “Boston Globe Top Places to Work” survey. Ms. Weger began her career at Nabisco Brands as Director, HR.

Ms. Weger earned a M.A., Human Resource Management from Fairleigh Dickinson University, and a Master’s Certificate, Six Sigma – Black Belt, from Villanova University. She is also a graduate of the University of Michigan’s Executive Human Resource Program.

Bruce Culleton, MD

Dr. Culleton joins ProKidney from CVS Kidney Care, a wholly owned subsidiary of CVS Health, where he was most recently Vice President and General Manager. Previously, he served as Vice President and Chief Medical Officer at CVS Kidney Care. Before joining CVS Health, he was Vice President, Global Clinical Development and World Wide Vice President, Medical Affairs, Medication and Procedural Solutions at Becton Dickinson; and previously Vice President, Renal Therapeutic Area at Baxter Healthcare. Prior to beginning his industry career in 2007, Dr. Culleton was a Clinical Associate Professor, Department of Medicine at the University of Calgary.

Dr. Culleton holds a Bachelor’s degree in Medical Science and a Doctor of Medicine degree from Memorial University of Newfoundland; and a Master’s degree in Business Administration from Northwestern University, Kellogg School of Management. He completed a specialization in Internal Medicine and Nephrology through the Royal College of Physicians and Surgeons of Canada, as well as a fellowship in Clinical Epidemiology at Boston University, Framingham Heart Study.

Ashley H. Johns, MSHS

Ms. Johns has served as ProKidney’s Senior Vice President, Head of Global Clinical Operations since December 2022. Prior to that, Ms. Johns served SVP, Clinical Operations and as Vice President of Clinical Operations from March 2019, where she managed multiple cell therapy programs for ProKidney. She has extensive knowledge in the neurological and regenerative medicine therapeutic areas, having managed over 20 clinical trials from Phase 1 through Phase 4. From March 2016 to March 2019, Ms. Johns established and operated Johns Clinical Consulting as its President to provide clinical operation consulting services to ProKidney, its sole client. Ms. Johns was responsible for overseeing the clinical development of and the regulatory requirements for the REACT program of ProKidney when working at Johns Clinical Consulting. From June 2010 to March 2016, Ms. Johns worked on multiple cellular therapy programs at ProKidney and Tengion, a regenerative medicine company, and site levels, including, PMG Research, Inc., Advance Neurology and Southeast Area Health Education Center, prior to joining ProKidney. Ms. Johns received her B.S. in clinical research from the University of North Carolina at Wilmington and her Master’s of Science in Health Science degree in Clinical Operations and Healthcare Management from George Washington University.

Joseph Stavas, MD, MPH

Dr. Stavas has served as ProKidney’s Senior Vice President of Clinical Development and Interventional Procedures since December 2022. He joined ProKidney as Senior Vice President of Clinical Development in October 2019 and led the strategic advancement of clinical trials and scientific discovery and development. He brings over 30 years of experience in medical practice, academics and research endeavors and has been affiliated with ProKidney since 2012. He also serves as liaison between consultants, clinical investigators and scientists, and is actively involved in trial implementation and medical oversight. From May 2016 to October 2019, Dr. Stavas served as the Chairman of the Department of Radiology and was responsible for clinical and academic operations, research, and healthcare system strategy at Creighton University School of Medicine, an academic university and a healthcare system provider. From October 2005 to December 2008, Dr. Stavas served as the Division Chief for Clinical Interventional Radiology Procedures and was responsible for research trials and division operations at the University of North Carolina at Chapel Hill Hospital. Dr. Stavas holds a M.D. degree from Creighton University School of Medicine and completed his Radiology Residency at the University of Minnesota—Minneapolis. He attended the University of California San Diego for subspecialty training in Interventional Radiology at UCSD Hospital. Dr. Stavas also earned a Master of Public Health degree in Health Policy and Management from the University of North Carolina at Chapel Hill.