Idronoxil Suppository Combine With Radiotherapy for Metastatic Prostate Cancer

Who is it for? Patient may be eligible for this study if they have late stage metastatic prostate cancer which is castrate resistant and have metastatic lesions that are suitable for radiotherapy. Study details There are two groups of patients in this study and no randomisation. The two groups will have two different doses of idronoxil (NOX66), representing a 2-step dose escalation. Both groups receive the same standard radiotherapy dose. Group 1 will receive the lower dose (400 mg) of idronoxil suppository daily and Group 2 800 mg daily. Recruitment into Group 2 will only commence once all Group 1 patients have completed the 13-day treatment course of idronoxil suppository without excessive unexpected toxicity. The total treatment duration will be 13-15 days for both groups depends on whether radiotherapy is given on consecutive days or over the weekend. Day 0: commence idronoxil (NOX66) Days 1-5: 1 or 2 lesions will receive 20 Gy (radiotherapy dose unit) radiotherapy in 5 daily fractionated doses and continue daily NOX66 Day 6-12: Continue NOX66 (the duration of NOX66 will be 13-15 days depends on whether radiotherapy is given on consecutive days or over the weekend). Both groups will have prostate-specific membrane antigen positron emission tomography (PSMA-PET) scans before starting treatment and three months after the last fraction of radiotherapy to assess treatment response.