(UroToday.com) High-risk localized prostate cancer is managed with either surgery, or the combination of radiation therapy plus androgen deprivation therapy (ADT). Despite treatment with curative intent, approximately half of patients experience recurrence, with significant prostate cancer specific mortality. The NADIR trial aims to test the hypothesis that the addition of PARP inhibition to definitive radiotherapy plus ADT will improve outcomes of men with high-risk localized prostate cancer. This is based on preclinical data suggesting that PARP inhibition serves as a radiosensitizer regardless of the mutation status of homologous recombination genes such as BRCA2.