Paul T. Addison
Vice Chair and Treasurer, Board of Trustees
Maimonides Medical Center
Paul T. Addison has served on the Board of Trustees of Maimonides Medical Center since 2005. He’s had a distinguished career in finance and government; he has chaired the Budget and Finance Committee and contributed to the Executive and Medical Matters Committees.
Mr. Addison began his professional journey as a Senior Loan Specialist with the U.S. Department of Commerce. He later held leadership roles in the private sector, including Vice President and Secretary at BanCap Corporation, Managing Director and Senior Credit Officer at CitiCorp, and Managing Director at Salomon Smith Barney/Citigroup.
He’s a graduate of Howard University and Harvard Business School.
Dr. Donna Astion
Board Trustee, Chair of Quality and Safety Committee and Academic Affairs Committee; Treasurer of Research and Development Foundation
Maimonides Medical Center
Dr. Donna Astion is an accomplished orthopedic surgeon with extensive experience in medical practice and healthcare administration. She also serves on several Maimonides committees including Strategic Planning and Executive. She has served on the Board of Trustees of Maimonides Medical Center since 2010.
She graduated from Boston University’s Sargent College with a BS in physical therapy, earned her MD from Icahn School of Medicine at Mount Sinai, and obtained an MPH from Columbia University Mailman School of Public Health.
Joseph F. Bruno
Former Commissioner and CEO
New York City Fire Department; Office of Emergency Management; Helen Keller Services for the Blind
Joseph F. Bruno began his legal journey in 1971 with the City of New York’s Law Department. Over the next two decades, he held progressively senior roles, including Chief of the Tort Division and General Litigation Division. He held executive roles as Fire Commissioner of the New York City Fire Department, Commissioner of NYC’s Office of Emergency Management, and CEO of Helen Keller Services for the Blind. He has made a lasting impact on healthcare through his contributions as a hospital trustee.
He holds a JD from St. John’s Law School and a BS in economics from City College of New York.
Monsignor David L. Cassato
Pastor Emeritus; Board Trustee since 2002
St. Athanasius – St. Dominic Parish; Maimonides Medical Center
Monsignor David L. Cassato has served on the Board of Trustees at Maimonides Medical Center since 2002.
He was appointed Chaplain of Bishop Kearney High School in 2003, and in 2015, he became Administrator of St. Dominic Parish. In 2017, he was promoted to Deputy Chief Chaplain of the New York City Police Department, and in 2020, he was appointed Vicar of Catholic Schools for the Brooklyn and Queens Diocese. Monsignor Cassato was promoted to Assistant Chief Chaplain on May 27, 2022, and retired as Pastor of St. Athanasius – St. Dominic Parish on June 30, 2022, now holding the title of Pastor Emeritus. He was ordained a priest in 1972. Cassato celebrated his first Mass at Holy Family in Brooklyn and currently serves as Pastor Emeritus.
He earned a Bachelor of Arts in Philosophy from Cathedral College of the Immaculate Conception and a Master of Divinity from Our Lady of the Angels Seminary.
Robert E. Foran
Former Chief Financial Officer
Metropolitan Transportation Authority (MTA) of New York State
From 2010 to 2021, Robert E. Foran served as the Chief Financial Officer of the Metropolitan Transportation Authority (MTA) of New York State, overseeing financial strategy and managing the MTA’s complex finances. He has served on numerous boards, including the Riverside Park Conservancy, where he was a Board Member from 1994 to 2014, Chair from 1998 to 2003, and now serves as Chair Emeritus. Prior to his role at the MTA, Robert held senior positions in prestigious financial institutions, including Managing Director and Senior Advisor at Samuel A. Ramirez & Co. and Senior Managing Director at Bear Stearns, where he managed the Public Finance Department and served on the Board of Directors. He also held key roles at Morgan Stanley and Lehman Brothers and began his career as a Senior Accountant at Arthur Andersen & Co.
He has an MBA from Harvard Business School and a BS in accounting from Bob Jones University, where he graduated magna cum laude.
Yeshua Leib Fruchthandler
Management
FBE Limited
Yeshua Leib Fruchthandler is a dedicated community leader serving on the boards of Mesivta Yeshiva Rabbi Chaim Berlin and Torah Umesorah, which focuses on Torah education for Jewish children.
He holds a management position at FBE Limited, a real estate acquisition company founded by his father, Abraham Fruchthandler.
Kenneth D. Gibbs
President and CEO; Chair of the Board
Maimonides Health
Kenneth D. Gibbs has served as President and CEO of Maimonides Medical Center since 2016 and became President and CEO of Maimonides Health in 2022. Under his leadership, Maimonides has experienced significant growth. Today, he oversees a staff of more than 7,000 and an annual budget of $2 billion, helping the system deliver award-winning care to more than 320,000 patients each year across three hospitals and over 80 community practices.
He joined the Board of Trustees in 2013, where he chaired the Strategic Planning Committee and, a year later, the full Board. Prior to joining Maimonides, Mr. Gibbs spent more than 30 years in public finance, managing large-scale financing projects for public programs and facilities nationwide.
Mr. Gibbs holds a BA from Harvard College. Learn more about Mr. Gibbs.
Eugene Keilin
Co-Founder
KPS Capital Partners
Eugene Keilin co-founded KPS Capital Partners, a firm with portfolio companies generating over $20 billion in annual revenue and employing approximately 48,000 people worldwide. He formerly chaired the Municipal Assistance Corporation for New York City during its 1975 financial crisis. He was Chair of the Citizens Budget Commission from 1999 to 2002.Mr. Keilin was formerly Chair of the Municipal Assistance Corporation for the City of New York, an agency created in 1975 to deal with New York City’s financial crisis.
He is a graduate of Rice University and Harvard Law School.
Mortimer Klaus
President
MLA Properties; Beth David Synagogue; Board Trustee since 1984
Since 1984, Mortimer Klaus has been dedicated to improving the lives of patients at Maimonides Medical Center, where he has served on several committees, including Finance, Executive and Strategic Planning, Investment, and Nominating. Most notably, he served as Vice Chair of the Board of Trustees for 10 years and was Chair of Medical Matters and Quality Control for 20 years. He is also the founder of the Mortimer and Barbara Klaus Family Foundation, established in 1975. The foundation has benefited numerous organizations, donating millions of dollars to healthcare, the arts, and underserved communities. Mr. Klaus is President of MLA Properties and Beth David Synagogue in Amenia, NY.
He holds degrees from New York University and New York Law School and is a member of the New York State Bar.
Dr. Juan C. Kupferman
Division Chief, Pediatric Nephrology and Hypertension; President of Medical Staff; Chair of Executive Medical Council
Maimonides Medical Center
Dr. Juan C. Kupferman is a pediatric nephrologist and hypertension specialist with over 25 years of experience. He has built a nationally recognized pediatric hyperextension program at Maimonides Medical Center. As President of the Maimonides Medical Staff and Chair of the Executive Medical Council, he has played a crucial role in shaping the vision and mission of the Maimonides Children’s Hospital. Dr. Kupferman has served as the Division Chief of Pediatric Nephrology and Hypertension at Maimonides Medical Center.
He earned his medical degree from the University of Buenos Aires and master’s degrees from Columbia University and the University of Oviedo.
Michael Mager
Cofounder and CEO; Precision Neuroscience
Founding Partner; Ridge Road Partners
Michael Mager joined the Maimonides board in 2025. Since 2020, he’s been a founder and CEO of Precision Neuroscience’s management, leading fundraising, recruitment, commercial rollout, communications, and strategy, and also has been a Board member since its inception. He’s also been a founder of Ridge Road Partners since 2013.
Mr. Mager is a graduate of Harvard University and University of Cambridge.
Dr. Eliza Ng
Chief Medical Officer
CAIPA IPA and CAIPA MSO
Dr. Eliza Ng leads medical operations at CAIPA IPA and CAIPA MSO, serving over 450,000 patients with a focus on value-based care. She is active in public health through board and committee service including the American Heart Association.
Dr. Ng’s prior roles include Chief Medical Officer of Population Health at RWJBarnabas Health System, where she improved clinical outcomes and employee engagement, and senior positions at Montefiore Health System and EmblemHealth. Her career also spans leadership in digital health as the founding Chief Medical Officer of Curio Digital Therapeutics.
She holds a BA from Yale University, an MD from Drexel University, and an MPH from Columbia University.
Frank Naccarato
Insurance and Financial Services Executive; Executive Vice President
Federation of Italian American Organizations of Brooklyn (FIAO)
Frank Naccarato has over 45 years in insurance and financial services. A Vietnam veteran and former designer, he served as Chair and President of FIAO and currently acts as Executive Vice President. He has also been honored by Brooklyn Borough President Marty Markowitz and State Senator Marty Golden.
His contributions extend to his roles as past President of the Bensonhurst and Bay Ridge Kiwanis Club, Vice Commander of the American Legion-George Washington Memorial Post 1872, and a member of City Comptroller Alan Hevesy’s Italian American Advisory Council. Frank serves on Community Board 11, Community Board 18, the Board of Trustees of Maimonides Medical Center, and the Executive Board of the Brooklyn Council Boy Scouts of America.
Martin D. Payson, Esq.
Trustee Emeritus; Former Chair of the Board
Maimonides Medical Center; Former Trustee of NYU and Howard University
Martin D. Payson has been a Trustee of Maimonides Medical Center for over 30 years, serving as Chair for 18 years, and is currently Trustee Emeritus.
He served as General Counsel and Vice Chair of Time Warner before retiring in 1992. He began his legal career at Paul, Weiss, Rifkind, Wharton & Garrison as an Associate Attorney from 1961 to 1967, with a leave from June 1963 to May 1964 to serve as an Instructor at the University of Michigan Law School. From 1967 to 1970, he was a Partner at Polier, Tulin, and Payson. Martin then joined Warner Communications, which later became Time Warner, where he served as General Counsel until 1990, and remained as Vice Chair until his retirement in 1992.
He holds a BA from Cornell University and an LLB cum laude from NYU Law School.
Peter Rebenwurzel
Owner; Managing Member; Vice Chair of the Board
Coney Realty; Coney Management, LLC; Maimonides Medical Center
Peter Rebenwurzel is Vice Chair of the Board of Trustees at Maimonides Medical Center, where he has served for nearly 20 years, contributing significantly to healthcare leadership and governance. A civic leader on Brooklyn Community Board 12 for 35+ years, he co-founded Shema Kolainu/Hear Our Voices school for autistic children.
He also manages over 8,000 NYC apartments through Coney Realty and Coney Management. He completed his high school and advanced Jewish studies at Yeshiva Torah Vodaath while simultaneously earning his degree from Brooklyn College.
Erminia Rivera
Vice Chair; Board Trustee since 2010; Chair
Gilbert Rivera Charitable Foundation; Family Businesses (AM&G Waterproofing; Park Avenue Building and Roofing Supplies); Maimonides Medical Center
Erminia Rivera’s longstanding commitment to Maimonides Medical Center includes her service on the Board of Trustees since 2010, where she has served as Vice Chair for the past six years, ensuring the delivery of high-quality healthcare services to the community. She also chairs a charitable foundation and supports Maimonides Medical Center, where the Breast Imaging Center of Excellence is named in her honor.
Ms. Rivera is a business leader and community advocate deeply rooted in Brooklyn. She is a key member of two family-owned businesses, AM&G Waterproofing, LLC, and Park Avenue Building and Roofing Supplies, LLC, both established in the 1980s. Together, these companies employ over 250 people and play a significant role in the Brooklyn community, providing substantial economic development and employment opportunities.
David Spira
Board Member
Maimonides Medical Center
David Spira serves on 25 co-op and condo boards and supports local healthcare initiatives through his role at Maimonides Medical Center. He is a real estate executive with over 30 years managing multifamily, commercial, and institutional properties.
Aaron Twerski
Professor of Law
Brooklyn Law School
Aaron Twerski has taught law since 1986 at Brooklyn Law School, with visiting positions at Cornell, Boston University, University of Michigan, and a fellowship at Harvard Law School. He was formerly a trial attorney at the U.S. Department of Justice Civil Rights Division.
In 2015, he received the prestigious William L. Prosser Award from the American Association of Law School’s Torts and Compensation System Section, recognizing his outstanding contributions to tort law. As co-reporter for the American Law Institute’s Restatement of the Law (Third) Torts: Products Liability, he was named the R. Ammi Cutter Reporter for his exceptional performance.
He holds a BS from the University of Wisconsin and a JD from Marquette University School of Law.
Marty Waisbrod
Founder; Board Member
Promont; Maimonides Medical Center; Makor Disability Services
Marty Waisbrod founded Promont, a real estate development company with 150+ projects in the Tri-State Area. He serves on the board of Maimonides Medical Center, Makor Disability Services, and several religious schools. Since 1997, Mr. Waisbrod has been an active volunteer paramedic with Hatzolah, a volunteer emergency medical service organization, and is currently the captain of Hatzolah of Central Jersey, one of the largest divisions.
He graduated from Rabbinical College in 1997.
George Weinberger
Chair of the Board of Trustees; CEO
New York Community Hospital of Brooklyn; Integra Scripts, LLC
George Weinberger leads New York Community Hospital and Integra Scripts, LLC, specializing in pharmacy cost containment for healthcare institutions. He founded American Healthware Systems.
He holds degrees from Brooklyn College and NYU Courant Institute.
Michael Ziegler, Esq.
Healthcare Attorney and Educator
Columbia University Mailman School of Public Health; NYU Wagner School of Public Service
Michael Ziegler is a seasoned attorney with a practice dedicated to the healthcare industry and nonprofit organizations. Alongside his legal career, Mr. Ziegler has held adjunct professorial roles at Columbia University and NYU Wagner School of Public Service, teaching for more than 25 years.
He began his career as a full-time academic at Columbia University’s Mailman School of Public Health, where he taught and conducted research on government regulation of the healthcare industry.