Clinical trial Recruiting at 1 site Interventional Ages 18 to 90

MMA Embolization with NeoCast for Subacute and Chronic Subdural Hematoma

Official title: Pivotal Study of the Treatment of Symptomatic Subacute and Chronic Subdural Hematoma Via Middle Meningeal Artery Embolization With the NeoCastTM Embolic System (RADIANT)

Run by Arsenal Medical, Inc. · NCT07541404 · Data updated 2026-11-12

This trial tests whether the NeoCast Embolic System safely and effectively works to treat subacute or chronic subdural hematomas after surgery, compared with the Onyx liquid embolic.

Quick facts

Study typeInterventional
Ages18 Years to 90 Years
SexAll
Enrollment360 (estimated)
SponsorArsenal Medical, Inc.
Industry-sponsored
Drugs / interventionsradiation
Locations2 sites (New Haven, Connecticut and 1 other locations)
StatusRecruiting
StartedAugust 13, 2026
Main results expectedJanuary 2028
Study endsApril 2028
Registry record updatedSeptember 30, 2026
Trial IDNCT07541404 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults aged 18–90 with symptomatic subacute or chronic subdural hematoma ≥10 mm thick who are planned for MMA embolization within ±7 days of surgical evacuation and have pre-morbid functional status (mRS ≤ 2).

Probably not a fit

Patients outside the specified age range, with higher pre-morbid disability, non-symptomatic hematomas, or not undergoing MMA embolization within the defined timeframe may not benefit.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a multicenter, randomized, single-blind study evaluating the safety and effectiveness of the NeoCast Embolic System for embolizing the middle meningeal artery in patients who have undergone surgery for subacute or chronic subdural hematoma. Participants are randomized 2:1 to receive either NeoCast or Onyx LES, an FDA-approved embolic, with primary outcomes assessed at 90 days and follow-up through 180 days. The trial targets adults aged 18 to 90 with symptomatic SDH of defined thickness and specific neurological symptoms, to determine if the NeoCast system provides comparable or superior results to Onyx. Conducted at Yale and University of Washington Medical Center, it is sponsored by Arsenal Medical, Inc.

Why it matters

Potential benefit: If successful, the NeoCast system could offer a safe and effective embolization option to manage subdural hematomas and potentially improve recovery after surgery.

How similar studies have gone: Previous trials have compared embolic agents in MMA embolization, with some showing safety and potential efficacy, but the NeoCast approach in this specific surgical-augmented, randomized design is novel.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Participant whose age is ≥ 18 and ≤ 90 years;
* Pre-morbid mRS ≤ 2;
* Confirmed diagnosis of subacute or chronic subdural hematoma that measures ≥10 mm in greatest thickness;
* Participant presents with one or more of the following corroborating neurological symptoms: headache; cognitive decline; speech difficulty; gait impairment or imbalance; focal neurological deficit; and/or seizure, within the last 30 days;
* Participant is planned for middle meningeal artery embolization within ±7 days of surgical evacuation of hematoma via burr hole or craniotomy;
* Participant or Legally Authorized Representative/Person Responsible for consenting on their behalf understands the nature of the procedure, consents to participation in the study and provides a signed informed consent form;
* Participant (woman of child-bearing potential) with a current negative pregnancy test who has agreed to an appropriate method of contraception throughout the trial;
* Participant is willing to return to the investigational site for follow-up visits.

Exclusion Criteria:

* Diagnosed with acute SDH
* Participant with prior embolization of either MMA
* Participant with urgent or emergent (within 1 hour of assessment) subdural hematoma evacuation needed
* Participant with bilateral SDH where both sides require surgery or contralateral SDH \>5mm in greatest thickness
* Participant identified with potentially dangerous anatomic variations leading to increased procedural risk, risk of incomplete embolization, or unsafe access for MMA embolization (i.e., MMA originating from ophthalmic artery)
* Participant who presents with a meningioma ≥1 cm or \< 1 cm with mass effect
* Subjects with conditions placing them at high-risk for ischemic stroke who cannot be taken off anticoagulants for at least 7 days post-surgery
* Participant currently undergoing radiation therapy for carcinoma or sarcomas of the head or neck region
* SDH developed due to underlying condition or structure pathology (e.g., dural AV fistula, AVM, tumor, arachnoid cyst, ventriculoperitoneal shunt, spontaneous intracranial hypotension or previous craniotomy)
* Presumed microbial superinfection
* Participant who is breastfeeding
* Participant with life expectancy of \<1 year
* Participants with acute renal impairment that the investigator assesses could be at risk for contrast induced nephropathy
* Participant with a life-threatening allergy to radiographic contrast (unless treatment for allergy is tolerated or can be managed medically)
* Participant is allergic to any of the materials used in the NeoCast device or the Onyx LES commercial embolic device
* Participant who is currently participating or planning to participate within 6 months in another clinical research study

Where it's running

  • University of Washington Medicine - Harborview Medical Center
    Seattle, Washington, United States
    Recruiting
  • Yale Neurosciences Institute
    New Haven, Connecticut, United States
    Not yet recruiting

Study contacts

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.