Derivo 2 Heal vs Derivo 2: In-Stent Stenosis After Flow Diversion

February 12, 2026 updated by: Dr. Umut Yilmaz, Universität des Saarlandes

Derivo-ISS: A Prospective Randomized Study Comparing In-Stent Stenosis After Treatment With a Coated Versus Uncoated Flow Diverter (Derivo 2 Heal vs Derivo 2) for Intracranial ICA Aneurysms

The goal of this clinical trial is to learn whether a coated flow diverter leads to fewer in-stent narrowings (in-stent stenosis) than an otherwise identical uncoated flow diverter when used to treat intracranial aneurysms in routine clinical care. The main questions it aims to answer are:

Does the coated flow diverter reduce the rate and severity of in-stent stenosis compared with the uncoated flow diverter?

Are there differences in angiographic aneurysm occlusion and procedure-related complications between the two devices?

Researchers will compare treatment with the coated flow diverter (Derivo 2 heal) to the uncoated flow diverter (Derivo 2).

Participants will:

Receive endovascular treatment of their intracranial aneurysm with one of the two flow diverters assigned by randomization

Receive standard antiplatelet medication and follow-up imaging as part of routine care

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

This investigator-initiated, prospective, single-center randomized clinical study compared a surface-modified flow diverter (Derivo 2 heal; Acandis, Germany) with the corresponding uncoated device (Derivo 2) in the endovascular treatment of unruptured saccular internal carotid artery (ICA) aneurysms in routine clinical care. After confirmation of eligibility and written informed consent, patients were randomized in a 1:1 ratio to receive either the coated or uncoated flow diverter using a computer-generated permuted block randomization scheme with variable block sizes. Allocation concealment was ensured using sequentially numbered, opaque, sealed envelopes prepared by an independent study coordinator. Device diameter and length were selected according to a predefined institutional sizing standard based on angiographic measurements, independent of treatment allocation.

All procedures were performed under general anesthesia via a transfemoral approach using standard technique. No adjunctive coiling and no balloon angioplasty were performed. All participants received dual antiplatelet therapy with aspirin 100 mg/day and clopidogrel 75 mg/day initiated at least 3 days before the procedure and continued for at least 12 months; platelet function testing was not routinely performed.

Angiographic follow-up was scheduled at 3 and 9 months using digital subtraction angiography (DSA). In-stent stenosis (ISS) was defined as a segmental reduction of the contrast-filled parent vessel lumen within the stented segment compared with the immediate post-procedural angiogram. Because absolute calibration is limited in 2D projection imaging, ISS severity was assessed using a standardized ratio-based approach: the vessel diameter at the site of maximal stenosis was related to a reference segment in the petrous ICA, and the resulting ratio was compared with the corresponding ratio on the immediate post-procedural angiogram to quantify relative luminal narrowing over time. For descriptive purposes, high-grade ISS (>50%) was recorded. In addition, ISS was morphologically categorized as stenosis associated with visible stent deformation (e.g., focal flattening, incomplete expansion, segmental collapse, fish-mouth configuration) versus stenosis without visible deformation, the latter interpreted as predominantly related to intimal hyperplasia.

Aneurysm occlusion was assessed on follow-up DSA using the O'Kelly-Marotta (OKM) grading scale. Complete occlusion was predefined as OKM grade D (no residual aneurysm filling). Clinical events and adverse events were prospectively recorded during the periprocedural period and follow-up visits.

The primary objective was to compare the incidence and severity of ISS between the coated and uncoated flow diverter groups over time. Secondary objectives included comparison of aneurysm occlusion rates and evaluation of relationships between angiographic outcomes and device- or vessel-related factors.

Study Type

Interventional

Enrollment (Actual)

21

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Germany
    • Saarland
      • Homburg, Saarland, Germany, 66421
        • Saarland University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adults aged ≥18 years
  • Unruptured, saccular aneurysm of the internal carotid artery (ICA) suitable for single-device flow diverter treatment
  • Availability of angiographic follow-up imaging at both 3 and 9 months

Exclusion Criteria:

  • Fusiform or dissecting aneurysms
  • Requirement for multiple flow diverter implantation
  • Previous treatment of the target aneurysm
  • Contraindications to dual antiplatelet therapy

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Coated Flow Diverter (Derivo 2 heal)
Participants receive endovascular treatment of an unruptured intracranial internal carotid artery aneurysm using the coated flow diverter (Derivo 2 heal). Device diameter and length are selected individually based on angiographic measurements according to institutional routine practice. Periprocedural care and follow-up imaging are performed as part of standard care.
Device: Coated Flow Diverter
A surface-modified intracranial flow diverter stent with an anti-thrombogenic coating (Derivo 2 heal, Acandis, Germany) used for endovascular treatment of unruptured intracranial internal carotid artery aneurysms. Device diameter and length are selected individually based on angiographic measurements according to institutional routine practice.
Active Comparator: Uncoated Flow Diverter (Derivo 2)
Participants receive endovascular treatment of an unruptured intracranial internal carotid artery aneurysm using the uncoated flow diverter (Derivo 2). Device diameter and length are selected individually based on angiographic measurements according to institutional routine practice. Periprocedural care and follow-up imaging are performed as part of standard care.
Device: Uncoated Flow Diverter
The corresponding uncoated intracranial flow diverter stent (Derivo 2, Acandis, Germany) used for endovascular treatment of unruptured intracranial internal carotid artery aneurysms. Device diameter and length are selected individually based on angiographic measurements according to institutional routine practice.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
In-Stent Stenosis Severity (Ratio-Based Luminal Narrowing)
Time Frame: 3 months and 9 months after the procedure (DSA follow-up)
In-stent stenosis (ISS) quantified on follow-up digital subtraction angiography (DSA) using a standardized ratio-based approach: the diameter at maximal stenosis within the stented segment relative to a reference segment (petrous ICA), compared with the corresponding ratio on the immediate post-procedural angiogram to derive relative luminal narrowing over time. Higher values indicate greater luminal narrowing (ISS severity).
3 months and 9 months after the procedure (DSA follow-up)

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
High-Grade In-Stent Stenosis (>50%)
Time Frame: 3 months and 9 months after the procedure
Proportion of participants with high-grade in-stent stenosis defined as >50% luminal narrowing within the stented segment on follow-up DSA.
3 months and 9 months after the procedure
Complete Aneurysm Occlusion (OKM Grade D)
Time Frame: 3 months and 9 months after the procedure
Complete angiographic occlusion on follow-up DSA defined as O'Kelly-Marotta (OKM) grade D (no residual aneurysm filling).
3 months and 9 months after the procedure
Procedure-Related Complications
Time Frame: Periprocedural period through 9 months
Occurrence of periprocedural complications related to the endovascular treatment (e.g., thromboembolic events, hemorrhagic complications, device-related adverse events) recorded prospectively.
Periprocedural period through 9 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Universität des Saarlandes

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 9, 2021

Primary Completion (Actual)

April 1, 2025

Study Completion (Actual)

April 1, 2025

Study Registration Dates

First Submitted

February 12, 2026

First Submitted That Met QC Criteria

February 12, 2026

First Posted (Actual)

February 19, 2026

Study Record Updates

Last Update Posted (Actual)

February 19, 2026

Last Update Submitted That Met QC Criteria

February 12, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 90/21

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared due to local data protection regulations and because participant consent did not include public sharing of individual-level clinical and imaging data. Aggregated results will be reported in publications.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Aneurysm Cerebral

Clinical Trials on Coated Flow Diverter

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Madagascar

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe