Crizanlizumab Alone or in Combination With Nivolumab for Glioblastoma and Melanoma With Brain Metastases

This study is testing a drug combination — crizanlizumab (alone or with nivolumab) — in three groups of patients: melanoma with brain metastases that has failed immunotherapy, glioblastoma (a brain tumor) that has come back after treatment, and newly diagnosed glioblastoma of a specific genetic type. Crizanlizumab targets a protein called P-selectin that tumors may use to evade the immune system. **You may be eligible if...** - You are 18 or older in good general health (ECOG 0–1 for melanoma cohort; ECOG 0–2 for glioblastoma cohorts) - Melanoma cohort: You have melanoma that has spread to the brain, have had at least one prior immunotherapy regimen, and the disease has stopped responding - Glioblastoma cohort 1: You have recurrent or persistent glioblastoma after standard treatment (radiation + temozolomide) - Glioblastoma cohort 2: You have newly diagnosed glioblastoma of the MGMT-unmethylated type and have completed radiation therapy **You may NOT be eligible if...** - You are on high-dose steroids for brain symptoms - You have cancer spread to the lining around the brain (leptomeningeal disease) - You had a life-threatening reaction to prior anti-PD-1 therapy - You have had a recent brain bleed - You are pregnant or breastfeeding - You have an active autoimmune disease requiring systemic treatment - You have been exposed to crizanlizumab before Talk to your doctor to see if this trial is right for you.