This is a Phase 1, open-label, single-center, dose-escalation study evaluating the safety and tolerability of intra-arterial bevacizumab (IA-BEV) given as an adjunct to middle meningeal artery embolization (MMAE) in adults with non-surgical chronic subdural hematoma (cSDH). Up to 18 participants who are already scheduled to undergo MMAE as standard of care will receive a single dose of bevacizumab, delivered directly into the middle meningeal artery immediately before embolization, during the same procedure. Three dose levels (2.0, 3.5, and 5.0 mg/kg) will be tested using a standard 3+3 dose-escalation design to identify the maximum tolerated dose. The study will also collect imaging and blood biomarker data to help understand which patients may benefit most from this combined treatment approach.