Phase 1 Open-label Study of 123I-ATT001 in Subjects with Relapsed Glioblastoma

This early-phase study is testing a radioactive drug called 123I-ATT001 — which is injected directly into a brain cavity through a device called an Ommaya reservoir — as a potential treatment for recurrent glioblastoma (an aggressive brain tumor that has come back after prior treatment). **You may be eligible if...** - You are 18 or older - You have recurrent glioblastoma (IDH-wildtype, grade IV) confirmed by biopsy - You have an Ommaya reservoir (a small device surgically placed in the brain) with a cavity of at least 5 mL - Your disease has come back within the last 3 months based on imaging - There are no other suitable standard treatment options available - Your physical condition is good (ECOG 0 or 1) **You may NOT be eligible if...** - You do not have an Ommaya reservoir or the cavity is too small - You have other standard treatment options still available - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.