Global Clinical Leadership

Werner Kleophas

Physicians who choose to partner with DaVita have direct access to a network of leading clinical experts in our discipline. Together, DaVita's entire clinical team, including the Office of the Chief Medical Officer (OCMO) in the U.S., our European clinical leadership team and all of our physician partners, identify, shape and drive the patient programs that are adapted locally and implemented in Germany. We listen to our physician teammates because they know better than anyone what is best for their patients.

When determining our approach to care at DaVita, our clinical leadership team continuously innovates new and improved ways to address patients’ kidney care issues and their health-related quality of life.

Office of the Chief Medical Officer

DaVita’s Office of the Chief Medical Officer is composed of a group of experienced nephrologists committed to providing value for patients, delivering high-quality care, improving clinical outcomes and being responsible stewards of resources. OCMO focuses on the needs of DaVita’s medical directors and physician partners by strengthening clinical and operational partnerships and developing new tools and resources to help tackle the daily challenges in kidney care.

Mahesh Krishnan, MD, MPH, MBA, FASN | Chief Medical Officer, International; Group Vice President of Research and Development | @DoctorKrishnan

Before joining DaVita, Dr. Krishnan served as medical director and global development leader for Amgen’s ESA Epogen, where he played a key role in discussions with the FDA and the Centers for Medicare and Medicaid Services. He was also the head of global health economics for nephrology at Amgen and executive director of medical policy for all Amgen projects. Prior to Amgen he ran a successful private nephrology practice in Virginia for nearly five years. He currently serves on the editorial board of Nephrology News and Issues, is on the USRDS advisory committee, and is on the board of the ASN-FDA Kidney Health Initiative. He has written two books and has over 55 peer-reviewed publications. Dr. Krishnan earned his medical degree from Thomas Jefferson University, did his internal medicine training at Georgetown, and his nephrology fellowship at Johns Hopkins. He also holds a master’s degree in Public Health from Johns Hopkins University and an MBA in Medical Services Management from the Johns Hopkins Carey School of Business.

Werner Kleophas, MD, FASN | Chief Medical Officer, Germany

Prof. Dr. med. Werner Kleophas launched his career in the mid 1980s at the medical clinic of Ferdinand-Sauerbruch Hospital in Wuppertal. From there, he transferred to the diabetes research institute at the University of Düsseldorf and the nephrological clinic at Düsseldorf University Hospital. From 1990 to 2013 he worked at a joint practice in Düsseldorf as a physician in private practice, specializing in internal medicine and nephrology with an additional qualification in diabetology. Prof. Dr. Kleophas is one of the first specialized physicians in Germany to introduce combined programs for treating patients with diabetes mellitus and chronic kidney disease. He was also involved with the development of the Genius® dialysis system. He is a fellow of the American Society of Nephrology (ASN) and is a member of many professional associations and editorial boards for nephrology and diabetology. Prof. Dr. Kleophas is currently the chief medical officer of DaVita in Germany.

Stefan H. Jacobson, MD, PhD | CEO and Professor of Nephrology, Danderyd University Hospital

Prof. Dr. Stefan H. Jacobson is a professor at the Department of Nephrology, Karolinska Institutet, Danderyd University Hospital, Stockholm, Sweden. His main research interests are in the areas of chronic kidney disease (CKD) and hemodialysis, specifically, cardiovascular diseases and infections in CKD, leukocyte function in CKD and genetic factors in IgA nephropathy. Professor Jacobson is an active member of a number of professional associations including the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA), the American Society of Nephrology (ASN) and the International Society of Nephrology (ISN) and was also a past president of the Swedish Society of Nephrology. He serves as a reviewer to the editorial boards of several international nephrology journals. He has been and is a member of the board of various international, interventional and observational clinical studies, including the Membrane Permeability Outcome (MPO) study, the Dialysis Outcome Practice Pattern Study (DOPPS) and the Evaluation of the Clinical Use of Cinacalcet in Dialysis Patients (ECHO study). Professor Jacobson has been the editor of the Scandinavian Journal of Urology and Nephrology. Over his career he has published more than 180 papers and reviews in peer-reviewed journals.

Maciej Drożdż, MD, PhD | Chief Medical Officer, Poland; Medical Director, Europe and the Middle East

As medical director for DaVita’s operations in Europe and the Middle East, Dr. Drożdż worked for more than 20 years at University Hospital in Kraków and served as the head of the dialysis unit in the department of nephrology. He has written or contributed to nearly 40 journal publications, including six chapters in polish nephrological textbooks. His research focuses on cardiovascular challenges for dialysis patients and intradialytic anticoagulation. As both principal and co-investigator he took part in phase II, III and IV clinical trials.

André Weigert, MD, PhD | Chief Medical Officer, Portugal

Born in Rio de Janeiro, Brazil, Dr. André Weigert studied at the University of Lisbon, Portugal, before doing postgraduate training at Hospital S. Maria and Hospital Santa Cruz in Lisbon, Portugal, and Baylor College of Medicine in Houston, Texas. His professional credits include chief medical resident at the VAMC of Houston/BCM, the fellowship in nephrology at the University of Colorado, Denver and specialist degrees in internal medicine and nephrology (1996) and clinical pharmacology (2008). Additionally, Dr. Weigert obtained certification from the American Board of Internal Medicine (1992) and the American Board of Nephrology and Hypertension (1996), and was elected fellow of the American College of Physicians (1999). His work on more than 40 published studies (in English, Portuguese and French) includes several clinical studies involving the EVOLVE trial. Dr. Weigert currently works in the renal transplant unit of the Hospital Santa Cruz, is assistant professor of pharmacology at the University of Lisbon and is the Chief Medical Officer of DaVita in Portugal. He directs the dialysis unit, Eurodial, at Obidos-Gaeiras, with 170 patients—all of whom are doing online hemodiafiltration (HDF). He is also involved in studies of pulse wave velocity in patients undergoing HDF, as well as new approaches to anemia management. He participated in several ISN CMEs in African countries (including Angola, Mozambique, Zambia, Democratic Republic of Congo).

Abdulkareem Alsuwaida, MD, FRCPC, MSc | Chief Medical Officer, Saudi Arabia

Dr. Abdulkareem Alsuwaida received his medical degree from King Abdulaziz University and completed his postgraduate medical education and a master’s degree in clinical epidemiology in internal medicine and nephrology at the University of Toronto in Canada. Dr. Alsuwaida is chief medical officer for DaVita in the Kingdom of Saudi Arabia, as well as a professor of medicine at King Saud University School of Medicine and consultant in the nephrology division at the King Khalid University Hospital. Previously he served as chairman for the department of medicine and director of postgraduate education at King Saud University, and president of the Saudi Society of Nephrology. His research is focused on dialysis, glomerulonephritis and lupus nephritis, and he has published more than 40 papers on these topics. Dr. Alsuwaida is a fellow at The Royal College of Physicians and Surgeons of Canada, as well as a member of the Saudi Society of Nephrology, the American Society of Nephrology College of Physicians and the European Society of Nephrology.

Sylvia P. B. Ramirez, MD, MPH, MBA | Chief Medical Officer, Asia Pacific

Dr. Sylvia P. B. Ramirez is a clinical nephrologist and a population epidemiologist with more than 20 years of research, public policy and nephrology experience. Before becoming the chief medical officer for DaVita in Asia Pacific she was vice president of global research and development for Arbor Research Collaborative for Health, and remains a consultant there. She was principal investigator and coinvestigator for multiple projects for the United States Centers for Medicare & Medicaid Services, including the Evaluation of ESRD Disease Management Demonstration, the Quality Incentive Payment Demonstration and the ESRD Measures Support Work. She is also a coinvestigator for the Dialysis Outcomes and Practice Patterns Study. Dr. Ramirez has published multiple papers on ESRD care, and has led a variety of technical expert panels on the development of quality performance measures in U.S. dialysis facilities.

Grace Yan, MD, PhD | Medical Director, China

Before joining DaVita Kidney Care, Dr. Grace Yan worked at the prestigious Shanghai Renji Hospital, a class 3A hospital in China, where she spent 22 years in nephrology, including a post-doctoral year at the Renal Disease and Hypertension Department of the University of Colorado Health Science Center, Denver, Colorado. Dr. Grace earned her MD and PhD from Shanghai Jiao Tong University School of Medicine, where she currently advises MSc and PhD candidates. She is also a committee member of the Chinese Society of Internal Medicine and was a Youth Committee member of the Chinese Society of Nephrology. She has won a number of academic awards and has published extensively.

Mauricio Ruiz Martinez, MD | Chief Medical Officer, Colombia

Dr. Mauricio Ruiz Martinez has been Chief Medical Officer for DaVita in Colombia since 2013. Previously he served as Associate Professor Chair of Nephrology and Semiology on the faculty of medicine at Universidad del Rosario and at La Fundación Universitaria de Ciencias de la Salud, both in Bogotá, and served as director of dialysis services at San José Hospital for more than 10 years. Additionally, Dr. Ruiz was coordinator of the peritoneal dialysis programs at Fresenius Colombia from 2004 to 2009 and was a Genzyme renal advisor from 2008 to 2010. He has also contributed chapters to many books on internal medicine and nephrology and is coeditor of the latest edition of the nephrology text in the Collection of the CIB (Corporación de Investigaciones Biológicas) in Colombia.

Suresh Sankar, MD, MBBS, MBA, FRCP | Medical Director, India

Dr. Suresh Sankar has 16 years of experience as a Clinical Nephrologist and was a group medical director for 3 years. He is certified by the American Board of Nephrology and the American Board of Internal Medicine. An alumnus of Madras Medical College, Dr. Sankar completed his nephrology training at the University of Rochester in New York and is a Fellow of American Society of Nephrology and Fellow of the Royal College of Edinburgh. He has a keen interest in clinical research, epidemiology, and health systems and has published more than 50 original papers and abstracts on those topics. He was honored with the Indian Society of Nephrology’s Young Investigator Award and Janssen-Cilag Award of Excellence in 2006.


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