Caldera Health are developing non-invasive tests for prostate cancer to improve upon and replace the controversial serum PSA test. Prostate cancer is fast becoming the most frequently diagnosed cancer in men globally. It accounts for nearly 25% of cancer diagnoses in men and 1 in 7 men will be diagnosed within their lifetime. Screening asymptomatic men with serum PSA tests is controversial, due in part to the low sensitivity and high false positive rate, as well as the risks associated with overtreatment of indolent prostate cancer tumours. Through a series of clinical studies, Caldera has identified promising RNA biomarkers for use in a diagnostic test. In preliminary experiments on urine, we found that extracellular vesicles (EV) accounted for a far greater proportion of the prostate RNA in urine than cells. We have since optimised a simple and reliable process to concentrate urinary vesicles and then developed an efficient method to specifically isolate prostate-derived EV from urine. In 2018, we have performed qRT-PCR analysis on approximately 300 urinary EV samples collected from men scheduled for biopsy tests for prostate cancer. Preliminary results suggest that gene signatures with diagnostic accuracy as high or better than comparable urine tests on the market can be identified.