Clinical Leadership

Clinical Leadership

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 United States (U.S.), our European clinical leadership team and all of our physician partners — identifies, shapes and drives the patient programs that are adapted locally and implemented in Portugal. We listen to our physician teammates because they know better than anyone what is best for their patients.

Office of the Chief Medical Officer

DaVita established OCMO in the U.S. as a group of experienced nephrologists dedicated to working with the business leadership to provide value for patients, deliver high-quality outcomes and be responsible stewards of resources while always ensuring the highest level of care.

A prolific author and renowned authority on kidney disease, Allen R. Nissenson, MD, FACP, is emeritus professor of medicine at the David Geffen School of Medicine at UCLA, where he has served as associated dean and director of the dialysis program. Dr. Nissenson is a former president of the Renal Physicians Association (RPA) and, prior to that, served on the RPA board of directors as a special advisor to the president. Dr. Nissenson has also served as president of the Southern California ESRD Network. Read Allen's Blog »

Click here for more information on our entire clinical leadership team.

DaVita’s Clinical Leaders for Europe

Professor Jacobson, in addition to being CEO and professor of nephrology at Danderyd University Hospital, is the associate editor of the Scandinavian Journal of Urology. Prior to Danderyd University Hospital, Professor Jacobson served first as the Head of the medical division and then as the director of the nephrology Department at Karolinksa Hospital and Korolinksa Institute. He has written or contributed to over 150 publications in journals around the world, and focuses his research on inflammation and cardio-vascular disease, leukocyte function, transmigration of leukocytes, IgA nephropathy and cardio renal syndrome. Professor Jacobson also serves on several international study and steering committees, with a focus on the randomized controlled study of the effects of hemodialysis (membrane permeability outcome study, MPO study), the practice pattern in hemodialysis (dialysis outcome practice pattern study, DOPPS), and the effects of cinacalcet (ECHO).

As Chief Medical Director for DaVita’s operations in Europe and the Middle East, Dr. Drozdz 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.


Professor João Frazão is an Internist and a Nephrologist. He is a Senior Nephrologist Consultant at the Nephrology Department of the Hospital Sao Joao, Porto, Portugal, in addition to being Associate Professor of Medicine, at the School of Medicine, University of Porto. He joined DaVita Portugal in 2016 as Scientific Coordinator and became Chief Medical Officer for DaVita Portugal in June 2017.

He graduated in Medicine from the Medical School at the University of Lisbon, Portugal, in 1986 and received his PhD in Medicine from the University of Porto in 1999. João M. Frazão’s post-graduate training in Nephrology took place at the West Los Angeles Veterans Affairs Medical Center, USA, where he gained a Research Fellowship in the Nephrology Section and at the University of California, Los Angeles (UCLA). He gained his certification in Internal Medicine and Nephrology from the American Board of Internal Medicine.

He is a member of many professional societies including the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA), International, and Portuguese Societies of Nephrology. Professor Frazão was Vice President of the Portuguese Society of Nephrology between 2003 and 2009. From June 2005 until May 2008 he was ordinary council member of the ERA-EDTA. He was awarded with the title of Distinguished Fellow of the European Renal Association-European Dialysis and Transplantation Association in 2013. Founder member of the ERA-EDTA CKD-MBD working group and elected Advisor in January 2017. Professor Frazão was elected by the Portuguese Society of Nephrology, President for the Annual Portuguese Congress of Nephrology 2017. He was on the editorial boards of Nephrology Dialysis Transplantation for many years until April 2017, and he is on the editorial board of the Journal of Nephrology. He was on the editorial board of The Portuguese Journal of Nephrology and Hypertension for many years where he became Associate Editor. His publications include over 60 peer-reviewed papers in the area of chronic renal failure and secondary hyperparathyroidism and 11 book chapters.

Working with DaVita’s Clinical Leaders

DaVita believes that strong, quality leadership can improve the lives of patients by facilitating better patient care. Medical directors can stimulate superior clinical outcomes through effective leadership and higher standards. In Portugal, DaVita physicians work with a highly-skilled team of nephrologists who obtained significant dialysis and clinical nephrology experience in many of Portugal‘s leading clinical centers.

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Clinical Leadership

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