A phase II study of nivolumab with ipilimumab and cabozantinib in patients with untreated renal cell carcinoma brain metastases.

Abstract

TPS745 Background: A SEER analysis from 2010 to 2013 demonstrated that the incidence of brain metastases(mets) at the diagnosis of renal cell carcinoma(RCC) is 1.51%, and around 12% of patients(pts) with advanced RCC (aRCC) also had mets to the brain. Brain mets confer a poor prognosis. Local management strategies for brain mets from RCC include surgical resection, stereotactic radiosurgery and whole brain radiation therapy. Although systemic therapies including tyrosine kinase inhibitors and immune checkpoint inhibitors have been explored in aRCC pts with brain mets, prospective data is lacking. Cabozantinib is a potent small molecule inhibitor of multiple tyrosine kinases that was approved by FDA for pts with aRCC alone or in combination with nivolumab. Cabozantinib has demonstrated activity in patients with intracranial tumors. A phase III trial (COSMIC-313) recently evaluated cabozantinib in combination with nivolumab and ipilimumab compared to nivolumab plus ipilimumab and demonstrated significantly improved progression-free survival (PFS) in previously untreated pts with aRCC. The combination was found to be safe as frontline systemic treatment. The role of this combination in patients with aRCC with brain mets remains undefined. As such, we propose a study to assess the safety and efficacy of cabozantinib in combination with nivolumab/ipilimumab in RCC pts with untreated brain mets. We believe the results from this trial could provide additional treatment options for pts with RCC brain mets who are typically excluded from clinical trials. Methods: This is a phase II study to assess the safety and efficacy of the combination of nivolumab with ipilimumab and cabozantinib in pts with untreated brain mets from RCC until disease progression or intolerable toxicities or patient withdrawal. Planned accrual is 40 pts. Pts will be treated with nivolumab (3mg/kg) and ipilimumab (1mg/kg) IV every 3 weeks for 4 doses and cabozantinib 40mg daily. Then pts will be treated with nivolumab 480mg IV Q 4 weeks and cabozantinib 40mg daily until progression or intolerable toxicities or patient’s withdrawal. A lead-in group of 6 pts will be closely monitored for dose limiting toxicities(DLT). If stopping criteria (>3 patients develop DLTs) is met, then treatment will be switched to nivolumab plus cabozantinib omitting ipilimumab. The primary objective is intracranial progression free survival(PFS). Secondary objectives include intracranial safety, objective response rate (intracranial + extracranial) by modified RECIST v1.1 and RECIST v1.1, extracranial PFS and overall survival. This phase II trial is currently enrolling pts. Clinical trial information: NCT05048212 .