Genicular Artery Embolization Vs Observation for Symptomatic Knee Osteoarthritis

NCT ID: NCT04682652

Last Updated: 2025-10-03

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 100 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2023-08-01
• Study Completion Date: 2027-10-01

Brief Summary

The purpose of this clinical trial is to determine whether genicular artery embolization (GAE) is an effective way to treat knee pain from osteoarthritis. Pain from arthritis is often due to underlying inflammation in the joint. The inflammation is associated with increased abnormal blood flow going to the specific area of pain. If the investigator can reduce the blood flow, the inflammation can be reduced and the pain can be controlled.

The GAE procedure is an experimental procedure to decrease the blood flow (embolize) to the specific region of the knee that is causing the pain. This will be done by infusing microscopic spheres into the specific blood vessel (genicular artery) supplying the area of pain in the knee. This is done through a procedure which is called an angiogram, which is done entirely through a pinhole at the creased of the thigh, using twilight (conscious) sedation.

The investigators have already completed an initial trial at UCLA, and shown that this procedure is safe and effective. The purpose of this new trial is to compare outcomes of people undergoing the GAE procedure to those who do not undergo the procedure. A total of 100 patients will be enrolled, and 2/3 of the patients will be randomly selected to undergo the GAE procedure. 1/3 will not undergo the procedure. This is known as a randomized trial. During the trial, all subjects will also get MRIs and fluid withdrawn from their knee joints at various timepoints in order to precisely figure out how the procedure works on a closer (microscopic) level.

Detailed Description

This is a single-center, prospective, open-label randomized trial to compare outcomes of GAE versus observation, and to identify biomarkers and imaging endpoints that change in response to GAE.

Subjects will be considered enrolled in the study once they have provided informed consent and have been determined to meet all eligibility criteria. A total of 100 subjects will be enrolled in the double-arm study and will be followed for 24 months.

The study will involve a screening period in which patient eligibility is determined. Once eligibility is confirmed, subjects will then be randomized to GAE or observation in a 2:1 ratio. Group sample sizes of 67 and 33 achieve approximately 85% power to reject the null hypothesis of no difference in the clinical response defined by 50% or greater reduction in WOMAC between the treatment and observation arms with a significance level (alpha) of 0.050 using a two-sided two-proportions using Fisher's exact test. With 100 symptomatic knee osteoarthritis subjects, the power of study is approximately 85% where we assume a target response rate of 67.5% for the experimental arm and 31% for the observational arm with up to 20% drop-out rate prior to 6 months. All study subjects will undergo the initial procedures, consisting of a history and physical exam, dynamic contrast-enhanced knee MRI, blood serum and joint aspiration with biochemical analysis.

For the treatment arm, subjects will undergo GAE with Embozene microspheres (100 micron) (Varian Medical Systems). Observation group will not receive the GAE procedure at baseline, and will be counseled on conservative management with a referral or prescription for physical therapy. Follow-up visits will be at 1 month (± 2 weeks), 3 months (± 2 weeks), 6 months (± 2 weeks), 12 months (± 2 weeks), and 24 months (± 2 weeks) post-procedure. At these visits, subjects will complete the WOMAC, KOOS5, visual analog scale (VAS) pain score, undergo a directed physical examination, and report any new adverse events (AEs). At 6 and 24 months of follow-up, all subjects will also undergo dynamic contrast-enhanced knee MRI, and serum and joint aspiration with biochemical analysis.

At 6 months, subjects in the observation group will have the option to crossover to the GAE treatment arm. Subjects in the crossover group will then undergo GAE, with follow up at 1 month (± 2 weeks), 3 months (± 2 weeks), 6 months (± 2 weeks), 12 months (± 2 weeks), and 24 months (± 2 weeks) post-GAE. For the purposes of data analyses, the follow-up evaluations for crossover subjects will match those of the initial GAE subjects. For example, if a subject in the observation arm undergoes GAE crossover at 6 months, that will be considered the treatment visit, and then subject will undergo evaluation at 1, 3, 6, 12, and 24 months after GAE.

Conditions

Knee Osteoarthritis; Degenerative Joint Disease of Knee

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

GAE Treatment

Subjects will be treated with a genicular artery embolization (GAE) procedure performed with Embozene Microspheres. The microspheres will be delivered in a saline-contrast medium solution and will be delivered to the arteries supplying the areas of the subject's pain.

Group Type: EXPERIMENTAL

Embozene MicroSpheres

Intervention Type: DEVICE

Embozene is a medical device made by Boston Scientific approved in the United States for the treatment of hypervascular tumors and arteriovenous malformations. It consists of thousands of microscopic spheres that are injected into the artery in the knee going to the region of pain. One of the causes of pain in the setting of knee arthritis is increased blood flow going to the specific area of pain. The goal of this procedure is to decrease the blood flow (embolize) to the specific region of the knee that is causing your pain. This is done by infusing Embozene particles into the specific blood vessel (genicular artery) supplying the area of pain in the knee.

Observational

Subjects randomized to the observational group will not undergo the experimental GAE Treatment.

PI will offer subjects enrolled into the observational group to crossover to the experimental GAE Treatment group after they have completed their 6-month follow-up assessments.

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Embozene MicroSpheres

Embozene is a medical device made by Boston Scientific approved in the United States for the treatment of hypervascular tumors and arteriovenous malformations. It consists of thousands of microscopic spheres that are injected into the artery in the knee going to the region of pain. One of the causes of pain in the setting of knee arthritis is increased blood flow going to the specific area of pain. The goal of this procedure is to decrease the blood flow (embolize) to the specific region of the knee that is causing your pain. This is done by infusing Embozene particles into the specific blood vessel (genicular artery) supplying the area of pain in the knee.

Intervention Type: DEVICE

Other Intervention Names

Color-Advanced Microspheres; Microspheres for Embolization

Eligibility Criteria

Inclusion Criteria

• Provided informed consent
• Age ≥ 40 years and less than 80 years
• Ineligibility for or refusal of surgical management
• Moderate-severe knee pain as determined by visual analog scale > 5 out of 10
• Osteoarthritis based on X-ray. Kellgren-Lawrence score > 2 based on radiograph completed within 3 months of procedure date.
• Resistant/failed conservative treatment (e.g. NSAIDS/physical therapy/steroid joint injection/ hyaluronic acid joint injection) for at least 3 months
• Able to comply with all treatments and protocol follow-up visits

Exclusion Criteria

• Mild knee pain as determined by visual analog scale < 5 out of 10
• OA on knee radiograph resulting in greater than 20 degree varus or valgus angulation
• Moderate loss of kidney function, define as estimated glomerular filtration rate of less than 45 mL/min.
• Significant arterial atherosclerosis that would limit selective angiography
• History of fibromyalgia, autoimmune, or inflammatory disorder
• History of any lumbar spine surgery, spine injections, or radicular pain in the extremity believed to originate from the spine
• Allergy to iodinated contrast agents
• Active Infection or malignancy
• Recent (within 12 months) or active cigarette use
• Prior total or partial knee replacement in the subject knee
• Active pregnancy
• Uncorrectable bleeding diasthesis

• Minimum Eligible Age: 40 Years
• Maximum Eligible Age: 79 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Varian Medical Systems

INDUSTRY

Sponsor Role: collaborator

University of California, Los Angeles

OTHER

Sponsor Role: lead

Responsible Party

Siddharth Padia, MD

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Siddharth A Padia, MD

Role: PRINCIPAL_INVESTIGATOR

University of California, Los Angeles

Locations

UCLA Santa Monica Hospital

Santa Monica, California, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Aniket Joglekar, BA

Role: CONTACT

ajoglekar@mednet.ucla.edu

310-948-8026

Saima Chaabane, PhD

Role: CONTACT

SChaabane@mednet.ucla.edu

424-465-4482

Facility Contacts

Siddharth A Padia, MD

Role: primary

spadia@mednet.ucla.edu

3104817545

References

Padia SA, Genshaft S, Blumstein G, Plotnik A, Kim GHJ, Gilbert SJ, Lauko K, Stavrakis AI. Genicular Artery Embolization for the Treatment of Symptomatic Knee Osteoarthritis. JB JS Open Access. 2021 Oct 21;6(4):e21.00085. doi: 10.2106/JBJS.OA.21.00085. eCollection 2021 Oct-Dec.

Reference Type: BACKGROUND

PMID: 34703964 (View on PubMed)

Other Identifiers

22-001004

Identifier Type: -

Identifier Source: org_study_id