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Meet DaVita's Clinical Leadership Team

 Leadership Team

Physicians who choose to partner with DaVita have direct access to some of the world’s leading clinical experts in various areas of kidney care. DaVita’s clinical leadership team—including the Office of the Chief Medical Officer (OCMO), group medical directors and our physician partners—works together to identify, shape and drive the patient programs that are implemented in our more than 2,000 dialysis centers.

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.

Allen R. Nissenson, MD, FACP, FASN, FNKF | Chief Medical Officer

Prolific author and renowned authority on kidney disease, Allen R. Nissenson, MD, is emeritus professor of medicine at the David Geffen School of Medicine at UCLA, where he has served as director of the dialysis program and associate dean. Dr. Nissenson is a former president of the Renal Physicians Association (RPA) and served on the RPA Board of Directors as a special advisor to the president. Dr. Nissenson is a past president of the Southern California End-Stage Renal Disease Network. Read Allen’s Blog >>

Mahesh Krishnan, MD, MPH, MBA, FASN | Vice President, Clinical Innovation and Public Policy

Before joining DaVita, Dr. Krishnan served as medical director for Epogen and as executive director of medical policy for Amgen. During his time there, he also served as medical director and global development leader for Epogen, and played a key role in discussions with the FDA and the Centers for Medicare & Medicaid Services. Dr. Krishnan also served in private practice for four years in Virginia.

Stephen McMurray, MD, FACP | Vice President, Clinical Integrated Care Management Services 

Dr. McMurray received his medical degree from the Indiana University School of Medicine. He began his career at Fort Wayne Nephrology, Inc., a 35-physician multi-specialty group in Fort Wayne, Ind. In 1996, Dr. McMurray became a founding member of Renal Care Group (RCG) and later a formal board member. Most recently, Dr. McMurray served as medical director for integrated care, North America, at Fresenius Medical Care.

Mark Kaplan, MD | Vice President, Medical Affairs

Dr. Kaplancompleted medical school and a residency in internal medicine at Vanderbilt University, followed by a year as chief resident in internal medicine at the Nashville Veterans Affairs Medical Center. From there, he completed a clinical and research fellowship in nephrology and hypertension at Harvard University Medical School's Brigham and Women's Hospital in Boston, Mass. Dr. Kaplan practiced nephrology in Nashville, Tenn., where he launched and developed the practice's clinical research program. He served as the vice president of clinical research at Renal Care Group and then at Fresenius Medical Care. He served as chief medical officer at DSI Renal, Inc., prior to joining DaVita.

Robert Provenzano, MD, FACP, FASN | Vice President, Medical Affairs 

Dr. Provenzano is clinical  professor of medicine at Wayne State University School of Medicine in Detroit, Mich. He is also chief of the section of nephrology, hypertension and transplantation, as well as director of nephrology research at St. John Hospital and Medical Center in Detroit. He is past president of the Renal Physicians Association and current CEO of St. Clair Specialty Physicians, PC, a multistate nephrology practice.

David B. Van Wyck, MD | Vice President, Clinical Support Services

Dr. Van Wyck is emeritus professor of medicine and surgery at the University of Arizona College of Medicine in Tucson, Ariz., and immediate past cochair of the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF-KDOQI) Anemia Workgroup. Dr. Van Wyck has written or contributed to publications on basic iron metabolism and reticuloendothelial function, and on clinical aspects of iron and anemia in patients with chronic kidney disease.

John Robertson, MD | Vice President, Clinical Support Services

Dr. Robertson is founder and partner of Nephrology Associates Medical Group, Inc., the third largest nephrology group in the state of California, and serves as medical director for Yucaipa Dialysis, a DaVita center. He has been a member of DaVita's Physician Council for six years, is a medical director for the DaVita - Scan CMS ESRD Demonstration Project and is affiliated with Apex Research of Riverside, a private practice participating in clinical trials.

Robert Merrell, MD, FACP | Vice President, Clinical Risk Support 

Before joining DaVita's Office of the Chief Medical Officer, Dr. Merrell was a private practice nephrologist for 25 years, serving patients at Kidney Specialists of Southern Nevada for most of that time. A medical director at several DaVita centers over the years, he now oversees Siena Henderson Dialysis Center in Henderson, Nev. He is board-certified in nephrology and internal medicine and he is also a fellow in the American College of Physicians.

Martin Schreiber, MD | Vice President, Clinical Affairs – Home Dialysis

Dr. Schreiber comes to DaVita Kidney Care with nearly 40 years of experience in nephrology. Prior to this role, he worked primarily with Cleveland Clinic and held a number of key positions there, including Chairman of the Department of Nephrology and Hypertension and the Director of Home Dialysis. Additionally, he is an active educator and international lecturer with ongoing editorial responsibilities with the Journal of the American Society of Nephrology, American Journal of Kidney Disease and Peritoneal Dialysis International.

For more insight from OCMO, visit our Kidney Care Physician Video Library, featuring more than 50 videos on topics ranging from clinical initiatives and integrated care to home dialysis and medical director resources.

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