An interventional study of NeoCast Embolic System and Onyx LES, an FDA-Approved Commercial Liquid Embolic in Subdural Hematoma, sponsored by Arsenal Medical, Inc.. Recruiting at 2 sites in United States. Open to participants aged 18 Years to 90 Years. Per ClinicalTrials.gov, last updated 2026-09-30.
Sponsored by Arsenal Medical, Inc. · Not applicable, Interventional, and Treatment
The purpose of this study is to evaluate the safety and efficacy of embolization of the middle meningeal artery (MMA) using the NeoCast Embolic System for treatment of symptomatic subacute or chronic subdural hematoma (SDH) adjunctive to surgery.
This is a prospective, multi-center, randomized, controlled, single-blind pivotal trial to evaluate the safety and effectiveness of the NeoCast Embolic System in embolization of the middle meningeal artery (MMA) in surgically treated patients with symptomatic subacute or chronic SDH. Three hundred sixty participants will be randomized in a 2:1 ratio to be embolized with either the Arsenal Medical NeoCast Embolic System or Onyx LES, an FDA-approved commercial embolic. The Primary Effectiveness Endpoint will be measured at the 90-day timepoint post-treatment. Participants will be followed through 180 days.
112 studies on the registry are indexed under Hematoma, Subdural, Chronic; 49 are open to participants now.
This study's planned enrollment of 360 is above the median of 185 across 86 interventional studies indexed under Hematoma, Subdural, Chronic.
Browse Hematoma, Subdural, Chronic studies →Arsenal Medical, Inc. is the lead sponsor of 2 studies on the registry; 2 are open to participants now.
Compared within Hematoma, Subdural, Chronic, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Hematoma, Subdural. The counts are of registry records indexed under each term, refreshed daily. How we classify →
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants randomized to the NeoCast arm will have their MMA embolized with NeoCast adjunctive to surgery
Device: NeoCast Embolic System
Participants randomized to the active comparator control arm will have their MMA embolized with Onyx LES, an FDA-approved commercial liquid embolic adjunctive to surgery
Device: Onyx LES, an FDA-Approved Commercial Liquid Embolic
NeoCast will be used to embolize a participant's middle meningeal artery in an endovascular procedure before or after adjunctive surgery to drain the hematoma
Onyx LES, an FDA-approved commercial liquid embolic, will be used to embolize a participant's middle meningeal artery in an endovascular procedure before or after adjunctive surgery to drain the hematoma
Also known as: Active Comparator Arm
Comparison of NeoCast arm vs. Onyx LES arm for a composite endpoint of treatment failure events
The Primary Effectiveness Endpoint is a non-inferiority comparison of the NeoCast and Onyx LES groups for treatment failure as defined by the occurrence of any of the following events: 1. Residual or re-accumulation of the SDH (≥10 mm) on 90-day scan post-treatment (assessed by a blinded, independent Imaging Core Lab); 2. Re-operation (after index procedure) or surgical rescue within 90 days post-treatment (CEC adjudicated); 3. Any new, major disabling stroke, myocardial infarction (MI) or death from any (neurological) cause within 90 days post-treatment (CEC adjudicated)
Time frame: 90 Days post-treatment
Safety Outcomes including Device-related or Procedure-related Serious Adverse Events
CEC-adjudicated safety outcomes in both arms including: * Incidence of device-related Serious Adverse Events * Incidence of embolization procedure-related Serious Adverse Events * Incidence of device-related neurological deaths or disabling strokes within 30 days of embolization procedure * Incidence of device-related Adverse Events
Time frame: 180 days post-treatment
Superiority evaluation for successful distal penetration comparing NeoCast arm to the Onyx LES active comparator arm
Superiority evaluation for successful distal penetration comparing NeoCast arm to the Onyx LES active comparator arm
Time frame: Peri-procedural
Superiority evaluation for successful embolization comparing NeoCast arm to the Onyx LES active comparator arm
Superiority evaluation for successful embolization comparing NeoCast arm to the Onyx LES active comparator arm
Time frame: 90 days post-treatment
Superiority evaluation of complete hematoma resolution at 180 days comparing the NeoCast arm to the Onyx LES active comparator arm
Superiority evaluation of complete hematoma resolution at 180 days comparing the NeoCast arm to the Onyx LES active comparator arm
Time frame: 180 days post-treatment
Superiority evaluation of percent hematoma volume reduction at 30 days compared to post-treatment timepoint comparing the NeoCast arm to the Onyx LES active comparator arm
Superiority evaluation of percent hematoma volume reduction at 30 days compared to post-treatment timepoint comparing the NeoCast arm to the Onyx LES active comparator arm
Time frame: 30 days post-treatment
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Arsenal Medical, Inc.