Checkpoint immunotherapy is a revolutionary cancer treatment for chemotherapy resistant cancers like melanoma, kidney cancer and lung cancer. It had not been carefully studied in prostate cancer patients until 2016. Dr. Julie Graff (Oregon Health & Science University) and her team have reported “exceptional prostate cancer responders” to the checkpoint inhibitor pembrolizumab in prostate cancer patients with enzalutamide resistant cancers. These can occur within 3 months of the start of treatment – but before chemotherapy treatment. In a pioneering study, Dr. Graff found that certain men with advanced, enzalutamide-resistant prostate cancer exhibited exceptional responses to pembrolizumab, with near complete PSA reductions and resolution of metastases on CT scans. Now the PCF Research Enterprise detective work begins. Determining why these prostate cancer patients responded so successfully and durably, is critical for realizing the full capabilities of this potentially curative therapy, and provide life-extending solutions for men with the worst forms of prostate cancer. “Exceptional Responder Research” for antiPD-1 treatment is expanding in the PCF Research Enterprise. PCF currently has 6 research teams in the US and Europe focused on the detective work in making immunotherapy remissions a 100% predictable event for prostate cancer patients. PCF hopes to triple the number of precision immunotherapy R+D teams in 2017.