Debra Jeske Zack, MD, PhD. Chief Medical Officer

Debra Jeske Zack, MD, PhD

Chief Medical Officer

Debra Jeske Zack, M.D., Ph.D., has served as Exagen’s Chief Medical Officer since March 2020. Dr. Zack is a board-certified rheumatologist with broad experience as a strategic biopharmaceutical executive in the development of therapeutics for autoimmune disease. Dr. Zack oversees the overall strategy and execution of the company’s clinical development plans. She has extensive experience leading research, clinical development and medical affairs teams focusing on autoimmune disorders. Prior to joining Exagen, Dr. Zack served as Vice President, Clinical Development at Xencor, Inc.; Executive Director, Medical Scientific Leader, Biotherapeutics Development Unit at Novartis; and various positions in basic research, clinical development and medical affairs at Amgen.

As an associate professor, Dr. Zack was treating rheumatology patients for 10 years at UCLA prior to joining industry. She received her undergraduate degree from Texas Christian University and her M.D. and Ph.D. from the University of Texas Southwestern in Dallas before completing her residency and rheumatology fellowship at the UCLA School of Medicine.


Medical Degree: University of Texas Southwestern

Doctorate Degree: University of Texas Southwestern

Fellowship: UCLA School of Medicine, Division of Rheumatology

Residency: UCLA School of Medicine, Department of Internal

Medicine Internship: UCLA School of Medicine, Department of Internal Medicine


Board certified in Internal Medicine and Rheumatology

Active medical licenses in California and Texas

Professional Societies

American College of Rheumatology

American Association of Immunologists

American College of Physicians

Selected Publications

W Stohl, JT Merrill, RJ Looney, J Buyon, DJ Wallace, MH Weisman, EM Ginzler, B Cooke, D Holloway, A Kaliyaperumal, KR Kuchimanchi, TC Cheah, E Rasmussen, J Ferbas, SS Belouski, W Tsuji and DJ Zack. 2015. Treatment of systemic lupus erythematosus patientts with the BAFF antagonist “peptibody” blisibimod (AMG 623/A-623): results from randomized, double-blind phase 1a and 1b trials. Arthritis Res Ther. 17:215.

JA Markenson, AS Koenig, JY Feng, S Chaudhari, DJ Zack, D Collier, and A Weaver. 2013. Comparison of physician and patient global assessments over time in patients with rheumatoid arthritis: A retrospective analysis from the RADIUS cohort. Journal of Clinical Rheumatology. 19(6):317-23.

D van der Heijde, D Zack, J Wajdula, S Sridharan, A Koenig. 2014. Rates of serious infections, opportunistic infections, inflammatory bowel disease, and malignancies in subjects receiving etanercept vs. controls from clinical trials in ankylosing spondylitis: a pooled analysis. Scand J Rheumatol. 43(1):49-53. [Epub 01 Nov 2013]

M Hammoudeh, DJ Zack, W Li, VM Stewart and AS Koenig. 2013. Associations between inflammation, nocturnal back pain and fatigue in ankylosing spondylitis and improvements with etanercept therapy. J Int Med Res. 41(4):1150-9.

IE van der Horst-Bruinsma, DJ Zack, A Szumski, and AS Koenig. 2013. Female patients with ankylosing spondylitis: analysis of the impact of gender across treatment studies. Annals of the Rheumatic Diseases. 72:1221–1224.

V Strand, V Sharp, AS Koenig, G Park, Y Shi, B Wang, DJ Zack, and D Fiorentino. 2012. Comparison of health-related quality of life in rheumatoid arthritis, psoriatic arthritis, and psoriasis and effects of etanercept treatment. Annals of the Rheumatic Diseases. 71(7):1143-50.

C Bombardier, M Barbieri, A Parthan, DJ Zack, V Walker, D Macarios and JS Smolen. 2012. The relationship between joint damage and functional disability in rheumatoid arthritis: a systematic review. Annals of the Rheumatic Diseases 71(6):836-844.

NB Watts, C Roux, JF Modlin, JP Brown, A Daniels, S Jackson, S Smith, DJ Zack, L Zhou, A Grauer, S Ferrari. 2012. Infections in postmenopausal women with osteoporosis treated with denosumab or placebo: coincidence or causal association? Osteoporosis International 23(1):327-337.

H Hsu, SD Khare, F Lee, K Miner, Y-L Hu, M Stolina, N Hawkins, Q Chen, SY Ho, H Min, F Xiong, T Boone, and DJ Zack. 2012. A novel modality of BAFF-specific inhibitor AMG 623 peptibody reduces B-cell number and improves outcomes in murine models of autoimmune disease. Clinical and Experimental Rheumatology 30(2):197-201.

About Our Medical Review Process

Exagen content contributors bring extensive experience from lupus and autoimmune disease testing research to ensure our readers receive high-quality and safe health information.

Exagen articles are medically reviewed and medically fact-checked by rheumatology and autoimmune testing specialists to ensure that all factual statements about medical conditions, symptoms, procedures, tests, and standards of care are accurate and reflect current guidelines as well as the latest research. All topics are updated as new evidence becomes available and our editorial review process is complete.