Saud A. Sadiq, MD, FAAN, is the Chief Research Scientist and Director of the Tisch Multiple Sclerosis Research Center of New York (Tisch MSRCNY) and Founder and Director of the International Multiple Sclerosis Management Practice. These two institutions opened their doors together in 2006 and constitute the largest independent facility dedicated to MS in the world.

A neurologist, neuroscientist, and internationally recognized leader in multiple sclerosis research and patient care, Dr. Sadiq has dedicated more than three decades to advancing
understanding of MS and developing novel therapeutic approaches. Under his leadership, Tisch MSRCNY has grown into one of the world’s premier MS research institutes, known for its bench-to-bedside innovations and groundbreaking work in regenerative medicine.

Dr. Sadiq trained in internal medicine and neurology in Kenya, the United Kingdom, and the United States before completing a research fellowship in neuroimmunology at Columbia University. His academic career includes faculty appointments at Columbia University, Albert Einstein College of Medicine, and St. Luke’s–Roosevelt Hospital Center, where he served as Chairman of Neurology and Rehabilitation Medicine. Over the years, he has directed numerous MS research programs, chaired clinical and academic committees, and mentored dozens of research and clinical trainees who now hold positions across the globe.

An accomplished investigator, Dr. Sadiq’s research focuses on the molecular mechanisms of MS, the triggers of autoimmune activation, biomarkers of disease activity,
and—most notably—repair and regeneration within the central nervous system. He has led Phase I/II clinical trials, pioneered intrathecal treatment approaches, and secured extensive foundation
and philanthropic support for the Center’s stem cell and regenerative neurology programs. He is credited in over 100 scientific publications and has mentored over 140
young scientists through the Tisch MSRCNY Research Assistant Program. 

Dr. Sadiq is a Fellow of the American Academy of Neurology and a member of the American Association for the Advancement of Science, the Society for Neuroscience, and the International Society for Stem Cell Research. He has been recognized repeatedly as one of New York’s top neurologists, earning honors from New York Magazine, Castle Connolly, and numerous patient-driven awards.
He has delivered lectures at major academic institutions and global scientific forums, and served as a reviewer for over 2 dozen scientific journals.

Through his dual commitment to cutting-edge research and compassionate patient care, Dr. Sadiq continues to shape the future of multiple sclerosis treatment. His work at Tisch MSRCNY and
IMSMP reflects a central mission: to uncover the mechanisms of MS, drive innovation in therapeutic development, and improve the lives of people living with MS worldwide.

Dr. James W. Stark is a board-certified neurologist and MS specialist at the International Multiple Sclerosis Management Practice (IMSMP). He earned his bachelor’s degree with distinction from Boston University and completed medical school at the Albert Einstein College of Medicine in New York. He continued at Einstein for his neurology residency training, serving as Chief Resident in his final year. He then completed a two-year neuroimmunology fellowship at the Tisch MS Research Center of New York under Dr. Saud A. Sadiq, gaining deep expertise in MS and neuroimmunologic disorders. 

In addition to patient care, Dr. Stark serves as Associate Medical Director and the Director of Clinical Trials at IMSMP. In this role, he oversees studies that contribute to the development and evaluation of treatments for MS and presents clinical research at numerous medical conferences. He also directs our fellowship program for neurology residents to extend their training and develop a specialization in Multiple Sclerosis/Neuroimmunology. 

In 2019, Dr. Stark was elected a Fellow of the American Academy of Neurology (FAAN), a distinction awarded to neurologists who have demonstrated exceptional academic, clinical, and professional contributions to neurology and the neurosciences. Dr. Stark’s clinical excellence has also been recognized repeatedly in Castle Connolly’s Top Doctors listings.  

Dr. Stark’s clinical philosophy is rooted in patient education and empowerment. He is committed to breaking down the technical elements of MS, answering questions thoroughly, and making decisions by consensus with his patients. This personalized approach aligns with IMSMP’s practice-wide integration of advanced diagnostics, customized symptom management, and long-term quality-of-life strategies.  

Dr. Stark is a born and bred New Yorker who enjoys the cultural vibrancy of the city, from museums and Broadway shows to its diverse culinary scene. He enjoys cooking for his friends and family but wishes that his kitchen were twice the size! Dr. Stark happily admits that he is obsessed with his two Boston Terrier rescues, Jack and Stitch, who occasionally visit the Center on weekends (but only when patients are not around!). He lives in Manhattan with his husband, Will, an American Sign Language interpreter primarily serving the New York public school system. During the summer months, they enjoy the beaches of Long Island.  

Armistead D. Williams III, MD, is the Associate Medical Director at the International Multiple Sclerosis Management Practice. He received his BA with majors in biology and studio art at the University of Virginia. He received his MD and completed his medical internship at the University of Virginia Medical Center. He trained in neurology at The Neurological Institute of New York at Columbia University Medical Center, one of the nation's foremost neurology centers. During his residency, he was awarded the 2005 Daniel Sciarra Patient Care Award for outstanding patient care and humanism. He joined IMSMP in 2007 after a two-year neuroimmunology fellowship with Dr. Sadiq.

Dr. Mahsa Mohajery is a board-certified neurologist and fellowship-trained neuroimmunologist specializing in the diagnosis and management of multiple sclerosis (MS) and related neuroimmunologic disorders. She is known for her thoughtful, patient-centered approach, and for integrating cutting-edge scientific evidence with individualized clinical care. 

Dr. Mohajery completed her medical education in Iran before relocating to the United States to pursue advanced training in neurology. She completed her internship at Rutgers University in New Jersey, followed by a neurology residency at Hackensack University Medical Center, JFK Neuroscience Institute, where she was selected as Chief Resident in recognition of her clinical excellence, leadership, and commitment to education. 

Following residency, Dr. Mohajery completed a neuroimmunology fellowship at the Tisch MS Research Center of New York under the mentorship of Dr. Saud A. Sadiq, gaining advanced expertise in MS care and research. During her fellowship, she was deeply involved in both clinical care and research, with a focus on disease-modifying therapies, pregnancy-related MS management, and long-term outcomes in women living with MS. She has contributed to retrospective cohort studies and clinical research projects aimed at refining treatment strategies during pregnancy, the postpartum period, and other hormonally vulnerable stages of life. 

Dr. Mohajery maintains a strong interest in clinical research and academic medicine and has participated in research presentations and publications focused on optimizing treatment decisions within real-world MS populations. She is particularly passionate about translating research findings into practical guidance that empowers patients and supports improved long-term quality of life. 

Clinically, Dr. Mohajery is known for her empathetic and collaborative style. She places strong emphasis on patient education, shared decision-making, and individualized risk–benefit assessments when selecting therapies. She provides comprehensive, individualized MS care to patients of all ages and genders, with specialized expertise in women’s neurological health and MS during pregnancy and the postpartum period.

Outside of medicine Dr. Mohajery is a dedicated mother, an experience that has further shaped her understanding of the challenges patients face in balancing health, family, and professional life. This perspective informs her approach to care and her commitment to supporting patients not just medically, but holistically.