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Medical Directors

Member wellness drives every decision we make. Our diverse medical directors bring an average of 27 years of experience across private practice, hospitals, medical centers and managed care. Together, they provide trusted leadership to ensure members receive high-quality care that meets their unique needs.

Chief Medical Officer

Richard Pitts, D.O., Ph.D.

Expertise: Clinical Practice, Occupational Health, Hospital Leadership

Certifications: Diplomate, American Board of Emergency Medicine; Diplomate, American Board of Preventive Medicine

Deputy Chief Medical Officer

Zeinab Dabbah, M.D., J.D., MPH

Expertise: Primary Care; Commercial, Medi-Cal and Medicare Managed Care; Medical Group Operations

Certification: Diplomate, American Board of Internal Medicine

Medical Director, Medicare Programs

Steven Arabo, M.D.

Expertise: Internal Medicine, Medicare Managed Care  

Certification: Diplomate, American Board of Internal Medicine

Medical Director, CalAIM

C. Hsien Chiang, M.D., FASAM, FACCP, CCHP-P

Expertise: Public Health, Justice-Involved Populations

Certifications: Fellow, American Society of Addiction Medicine; Fellow, American College of Correctional Physicians

Medical Director, Medical Management

Himmet Dajee, M.D., FACS

Expertise: Cardiac and Thoracic Surgery

Certification: Diplomate, American College of Thoracic Surgery

Medical Director, BehaviorAL Health

Natalie Do, D.O., Pharm.D.

Expertise: Adult, Child and Adolescent Psychiatry

Certification: Diplomate, American Board of Psychiatry and Neurology

Medical Director, PACE

Donna Frisch, M.D.

Expertise: Internal Medicine

Certification: Diplomate, American Board of Internal Medicine

Medical Director, Delegation Oversight

Robin Hatam, D.O.

Expertise: Internal Medicine

Certification: Diplomate, American Board of Internal Medicine

Medical Director, Street Medicine

Claus Hecht, M.D.

Expertise: Emergency Medicine

Certification: Diplomate, American Board of Emergency Medicine

Medical Director, Equity and Community Health

Shilpa Jindani, M.D.

Expertise: Family Practice, Appeals and Grievance  

Certification: Diplomate, American Board of Family Medicine

Medical Director, Transplant/Credentialing

Richard Lopez Jr., M.D., FACS

Expertise: Transplant Surgery

Certification: Fellow, American College of Surgeons

Medical Director, Medical Management

Nguyen Luu-Trong, M.D., FAAFP, MBA

Expertise: Family Practice

Certification: Fellow, American Academy of Family Physicians

Medical Director, Whole Child Model

Thanh-Tam Nguyen, M.D., FAAP, MS

Expertise: Pediatrics, California Children’s Services

Certification: Fellow, American Academy of Pediatrics

Medical Director, Appeals and Grievances/Case Management

Tanu Shweta Pandey, M.D., MPH, FACP

Expertise: Internal Medicine, Preventive Medicine, Case Management  

Certification: Fellow, American College of Physicians

Medical Director, Quality

Mohini Sinha, M.D.

Expertise: Pediatrics

Certification: Diplomate, American Board of Pediatrics

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