Nivolumab With or Without Ipilimumab in Treating Patients With Refractory Metastatic Anal Canal Cancer
PRIMARY OBJECTIVES: I. To evaluate overall response rate (ORR) with nivolumab in patients with previously treated metastatic squamous cell carcinoma (SCCA) of the anal canal. (Part A) II. To determine an improvement in progression-free survival (PFS) when nivolumab is combined with ipilimumab versus (vs.) nivolumab alone in patients with previously...