Plain language summary of the HERO study comparing relugolix with leuprolide for men with advanced prostate cancer.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of a research study (known as a clinical trial) called HERO. The HERO study compared how well relugolix and leuprolide worked in lowering blood testosterone to sustained castration levels in men with advanced prostate cancer. Sustained castration is a blood testosterone level below 50 ng/dl from Day 29 through 48 weeks of treatment.

WHAT WERE THE RESULTS?: Researchers looked at 930 adult men with advanced prostate cancer: 622 of these men took relugolix (by mouth once daily) and 308 received leuprolide (injected every 3 months). The HERO study showed that more men taking relugolix (97%) achieved sustained castration through 48 weeks than men receiving leuprolide (89%). This decrease in testosterone also happened more quickly in men taking relugolix. In 184 men who were followed up for 90 days after completing treatment, blood levels of testosterone returned to normal in more men who took relugolix than men who received leuprolide. Side effects were similar among men taking relugolix or receiving leuprolide, and most were identified as mild or moderate in terms of how bad they were.

WHAT DO THE RESULTS OF THE STUDY MEAN?: In men with advanced prostate cancer and compared with those receiving leuprolide, more men taking relugolix had lower levels of blood testosterone. ClinicalTrials.gov NCT number: NCT03085095.