CYTOSHRINK: This phase II trial is assessing the effect of adding radiotherapy (stereotactic body radiation therapy - SBRT) to the standard of care treatment immunotherapy (ipilimumab/nivolumab), compared with immunotherapy as a standard alone treatment, in people with metastatic kidney cancerCytoreductive Stereotactic Hypofractionated Radiotherapy With Combination Ipilimumab/Nivolumab for Metastatic Kidney Cancer

Summary

This is a randomised trial with active comparator and experimental arms. Participants in the Active Comparator arm will receive the standard of care treatment of ipilimumab/nivolumab alone. Induction ipilimumab 1 mg/kg combined with nivolumab 3 mg/kg (I/N) every 3 weeks for cycles 1-4 followed by maintenance treatment with nivolumab 240mg every 2 weeks or 480mg every 4 weeks until disease progression (as determined by RECIST 1.1), intolerance, or patient/physician decision to stop treatment. Participants in the Experimental Arm will receive the standard of care treatment if I/N plus primary disease SBRT. Induction ipilimumab 1 mg/kg combined with nivolumab 3 mg/kg (I/N) every 3 weeks for one cycle, followed by SBRT to the primary disease in-situ, prior to cycle 2-4 of I/N. Patients randomized to SBRT will undergo radiation planning during the first cycle of I/N to their primary kidney mass, and then the radiation will be delivered between cycles 1 and 2 to a dose of 30-40 Gy in 5 fractions every other day over 1.5 weeks. Approximately one week following completion of SBRT, patients will start cycle 2 of immunotherapy as per standard of care. The total time elapsed between the start of cycle 1 and 2 of I/N should be no more than 6 weeks. After completion of up to four cycles of I/N, patients will proceed to standard of care maintenance treatment with nivolumab 240mg every 2 weeks or 480mg every 4 weeks until disease progression (as determined by RECIST 1.1), intolerance, or patient/physician decision to stop treatment.