Diwakar Davar MD, MSc

Dr. Diwakar Davar is a medical oncologist and hematologist at UPMC Hillman Cancer Center whose focus is treating advanced melanoma and testing new immunotherapies. He’s been nationally recognized for co-leading the team that developed the first human study using fecal microbiota transplants to change the gut microbiome in melanoma patients whose tumors had progressed past all standard therapies. Dr. Davar’s team at UPMC Hillman reduced tumors in 20% of patients and an additional 20% had disease stabilization, demonstrating that changing the gut microbiome can make a difference in advanced melanoma patients who hadn’t previously responded to immunotherapy.

Dr. Davar’s interest in immune therapy was kindled during residency and fellowship training in the 2010s. Two decades earlier, CTLA-4, a protein found on immune cells, was identified by Nobel Laureate James Allison and colleagues to be an immune checkpoint and was proposed as a potential therapeutic target to trigger antitumor immune responses. More than 20 years after the seminal proof-of-principle experiments in the preclinical setting, CTLA-4 inhibitors entered clinical testing and were FDA-approved in 2011 following pivotal trials in melanoma. This development reinvigorated the field of cancer immunotherapy and catalyzed the development of immune checkpoint inhibitors targeting other pathways including another protein, PD-1, across a spectrum of cancers.

Dr. Davar is a graduate of the National University of Singapore. He completed his residency in general internal medicine and fellowship in hematology/oncology at Pitt, mentored by Drs. Hassane Zarour and John Kirkwood, the principal investigators of the Melanoma and Skin Cancer SPORE. He also obtained a Master's in Clinical Research from Pitt’s Clinical and Translational Science Institute.