Intrathecal Chemoprophylaxis to Prevent Neurotoxicity Associated With Blinatumomab Therapy for Acute Lymphoblastic Leukemia

This study is testing whether injecting a small dose of methotrexate (a chemotherapy drug) directly into the spinal fluid (intrathecal) can prevent a serious brain side effect called neurotoxicity in patients receiving blinatumomab — a treatment for a type of blood cancer called B-cell acute lymphoblastic leukemia (ALL). **You may be eligible if...** - You are an adult receiving your first cycle of blinatumomab for relapsed, treatment-resistant, or MRD-positive B-cell ALL - Your kidney and liver function are adequate - You are HIV-negative - Your overall health status is reasonably good (ECOG 0–2) **You may NOT be eligible if...** - The cancer has already spread to your central nervous system (brain or spinal cord) - You have certain neurological conditions (seizures, stroke, paralysis, dementia, Parkinson's, or movement disorders) - You cannot receive intrathecal methotrexate (for medical reasons) - You have already been treated with blinatumomab before - You have another active cancer - You have an active serious infection Talk to your doctor to see if this trial is right for you.