Leadership Team

David Lewinsohn, MD, PhD

Chief Executive Officer


ViTi, Inc. is led by Dr. David Lewinsohn. A leader in the field of tuberculosis immunology research and a practicing pulmonologist by trade, Dr. Lewinsohn has valuable insight into the current state of diagnostics in his roles as Professor of Medicine and Adjunct Professor of Molecular Microbiology & Immunology at Oregon Health and Sciences University (OHSU). He has served on numerous advisory boards and committees to governmental agencies and has provided his expertise to private industry in various roles.


Deborah Lewinsohn, MD

Chief Scientific Officer


Dr. Lewinsohn’s experience as Head of the Division of Infectious Disease and as Professor of Pediatrics at OHSU provides her with intimate knowledge regarding existing diagnostic practices with respect to children suspected of having TB disease and the limitations associated with current diagnostic algorithms and technologies. Indeed, her positions within her field, both as a physician and researcher, allow her to assist ViTi in the design and implementation of the clinical studies that might serve to inform governmental agencies, NGOs, and private industry on the effectiveness of a TB diagnostic for children.


Melissa Nyendak, MD, MHSc

Director of Clinical Affairs


Dr. Nyendak has been instrumental in the management of ViTi’s current program to develop to a CD8+ T cell diagnostic to identify children with pulmonary tuberculosis. She also holds the title of Assistant Professor in the Division of Infectious Disease at OHSU. Dr. Nyendak’s background in developing strategies for processing health information developed as part of her Master of Health Science program are a valuable asset to ViTi. Nyendak was the co-lead author on the original paper describing the concept that is the crux of ViTi’s current pediatric TB diagnostic program.