Efficacy and Safety of Anti-angiogenic Therapy With IV Bevacizumab in Patients With Symptomatic Cerebral Arteriovenous Malformations

Inclusion Criteria: * Patient over 18 years of age * With a symptomatic cerebral AVM (chronic headache, focal neurological deficit, cognitive impairment, epilepsy) of Spetzler and Martin grade III, IV or V. * Whose symptoms are sufficiently severe to allow significant improvement with treatment: * MoCA score ≤ 25 and/or * NIHSS score ≥ 4 and/or * Epilepsy Balance Score ≥ 2 and/or * HIT-6 score ≥ 48 * With functional signs and symptoms not sequellar to a previous bleeding episode AND disabling (mRS\>1) * Ineligible for therapeutic intervention (endovascular or neurosurgery or radiosurgery) * With normal bone marrow, liver and kidney function * For women of childbearing potential: negative pregnancy test within 14 days of inclusion and effective contraception for up to 6 months after the end of treatment * Having received informed consent to participate in the study * Affiliated or beneficiary of a social security scheme Exclusion Criteria: * Known allergy to bevacizumab or an excipient. * Hypersensitivity to Chinese hamster ovary (CHO) cell products or other recombinant human or humanized antibodies. * Contraindication to cerebral MRI * Absolute or relative contraindication to gadolinium injection * Proteinuria ≥ 2+ on urine dipstick (patients with proteinuria ≥2+ on urine dipstick will need to have proteinuria ≤ 1g protein on 24-hour urine to be eligible) * Uncontrolled hypertension (PAS \>150 and/or PAD \> 100 mmHg) * History of hypertensive crisis or hypertensive encephalopathy * Congestive heart failure (New York Heart Association Grade II or higher) * Previous myocardial infarction or unstable angina in the preceding 12 months * Symptomatic peripheral vascular disease * Vascular disease (aortic aneurysm, aortic dissection) * Major surgery, open biopsy or major traumatic lesion within 4 weeks prior to inclusion, or anticipation of the need for major surgery during the study. * Biopsy or other minor surgical procedure, excluding placement of a vascular access device, within 7 days prior to inclusion * History of abdominal fistula, gastrointestinal perforation or intra-abdominal abscess in the 6 months prior to inclusion * Significant unhealed wound, ulcer or bone fracture * Thrombotic episode within 6 months prior to inclusion * Atrial fibrillation * Patient under legal protection * Pregnant or breast-feeding women