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Omkar Marathe, M.D.

Dr. Omkar Marathe, Medical Director of Clinical Trials at TOI
Rated 5 / 5 stars
My overall experience with the Doctor was very good. I felt relieved regarding my current health and my care in the future.
Dr. Marathe is one of the best M.D I have had the pleasure of being a patient for. He has helped me out by walking me through step by step with my whole treatment, has answered all my questions, and given me the best opinions on other treatment.
Very pleasant and caring.

Languages Spoken

English, hindi, Spanish


Long Beach
(562) 232-0550

3300 E. South St.
Suite 304
Long Beach, CA 90805

(562) 232-0558
Los Alamitos
(562) 264-5154

3851 Katella Ave.
Suite 355
Los Alamitos, CA 90720

(562) 264-5157


As a lifelong Southern Californian, Dr. Omkar Marathe earned his bachelor’s degree in neurosciences from UCLA (graduating with honors) and his M.D. degree from the David Geffen School of Medicine at UCLA. He trained in internal medicine at Scripps Green Hospital in San Diego and returned to Los Angeles to complete his fellowship in hematology/oncology at the UCLA-Olive View-Cedars Sinai program, where he had the opportunity to train in a wide array of clinical settings ranging from a county hospital to a tertiary academic center. He has conducted research and published papers in various disciplines of oncology including ocular melanoma and HER2+ breast cancer.

In addition to his role as a physician at The Oncology Institute, Dr. Marathe is also the Medical Director for the Clinical Research entity within TOI where he has served as Principal Investigator for over 40 studies. During his tenure at TOI, he has personally enrolled over 80 patients in clinical trials for various indications including early-stage and metastatic cancers, supportive care, as well as benign blood disorders.

Dr. Marathe is a fan of Los Angeles sports teams and also enjoys playing tennis, running, and traveling with his wife in his spare time.

Dr. Marathe is fluent in Spanish, Marathi, and Hindi.

Professional Memberships

  • American Society of Clinical Oncology (ASCO)
  • American Society of Hematology (ASH)
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