Daratumumab for Familial Cerebral Cavernous Malformations: A Single-Arm Safety and Efficacy Study

Inclusion Criteria:

* Age ≥ 18 years;
* Diagnosed with familial cerebral cavernous malformation (familial CCM) (diagnosis requires at least one of the following: multiple CCMs or ≥2 family members with CCM);
* Presence of clinical symptoms or history of symptomatic events: intracerebral hemorrhage, stroke, permanent or transient neurological deficits, seizures, disability, or any other neurological symptoms associated with cavernous malformations;
* Deemed unsuitable for surgical resection by a physician;
* Able to provide written informed consent;
* Participant is willing and able to attend outpatient follow-up visits.

Exclusion Criteria:

* Stable familial CCM lesions not requiring intervention;
* Presence of metal implants or other contraindications to MRI;
* History of statin therapy within the past 6 months;
* History of beta-blocker therapy within the past 6 months;
* Laboratory abnormalities: absolute neutrophil count \<1 × 10⁹/L, platelet count \<100 × 10⁹/L, ALT \>2.5× upper limit of normal (ULN), ALP \>2.5× ULN, bilirubin \>1.5× ULN, serum creatinine \>2× ULN;
* Known HIV positivity, hepatitis B virus seropositivity (excluding passive immunity from vaccination or immunoglobulin therapy), defined as HBsAg-positive and/or anti-HBs and anti-HBc positive, or known hepatitis C virus positivity;
* Chronic or ongoing active infections requiring systemic treatment (e.g., chronic renal infection, chronic chest infection with bronchiectasis, tuberculosis);
* Poorly controlled comorbidities, including chronic obstructive pulmonary disease (COPD), severe asthma, poorly controlled diabetes, renal and/or hepatic failure;
* Cardiovascular diseases, including unstable angina, acute myocardial infarction (within 6 months prior to screening), congestive heart failure (NYHA Class II), arrhythmias requiring treatment (excluding premature beats or minor conduction abnormalities), deep vein thrombosis (excluding stable muscular vein thrombosis as judged by the investigator), pulmonary embolism, or other severe thromboembolic events, or history of deep vein thrombosis, pulmonary embolism, or severe thromboembolic events within 6 months prior to enrollment with a risk of recurrence as assessed by the investigator;
* Participation in other interventional medical research or clinical trials within 4 weeks prior to screening (observational, natural history, or epidemiological studies without interventions are allowed);
* Known allergic reactions to infused protein products;
* Pregnancy (positive urine or serum pregnancy test in premenopausal women without documented surgical sterilization) or lactation;
* Any condition (e.g., substance abuse, alcohol dependence) that, in the investigator's opinion, may compromise the participant's compliance with study requirements;
* Participant or legal guardian unable to provide informed consent for the study.