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Genicular Artery Embolization Vs Observation for Symptomatic Knee Osteoarthritis

GRAVITY: Genicular Artery Embolization Versus Observation for the Treatment of Symptomatic Knee Osteoarthritis: a Randomized Controlled Trial

Status
Active, not recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04682652
Acronym
GRAVITY
Enrollment
100
Registered
2020-12-24
Start date
2023-08-01
Completion date
2027-10-01
Last updated
2026-04-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Degenerative Joint Disease of Knee, Knee Osteoarthritis

Keywords

Microspheres, Artery Embolization, Knee Osteoarthritis, Chronic Pain, Embozene

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 120 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 During the trial, all subjects will also get MRIs and fluid withdrawn from their knee joints at various timepoints in order to precisely figure out how the procedure works on a closer (microscopic) level.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 80 and 40 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 120 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.

Interventions

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.

Sponsors

University of California, Los Angeles
Lead SponsorOTHER
Varian Medical Systems
CollaboratorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

A total of 120 subjects will be enrolled in the double-arm study, subjects will be randomized to GAE or observation in a 2:1 ratio (80 assigned to GAE, 40 assigned to observational). Subjects in the observation group will have the option to crossover to the GAE treatment arm after they've completed their 6-month follow-up time point. Subjects who crossover to treatment arm will undergo the GAE procedure and undergo all subsequent follow-up visits (1 month, 3 month, 6 month, 12 month, 24 month).

Eligibility

Sex/Gender
ALL
Age
40 Years to 79 Years
Healthy volunteers
No

Inclusion criteria

Subjects must meet all of the following inclusion criteria in order to be eligible for this study: * 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

Subjects that meet any of the following

Design outcomes

Primary

MeasureTime frameDescription
Changes in clinical response6 monthsThe primary evaluation is the change in clinical response, measured by The Western Ontario and McMaster Universities Arthritis Index (WOMAC). The primary endpoint is percentage of subjects achieving at least a 50% reduction in WOMAC at 6 months with an intent-to-treat analysis.

Secondary

MeasureTime frameDescription
Short term clinical outcomes1-3 months• Compare clinical success rates (defined as at least 50% reduction in WOMAC) between GAE and observation at 1 and 3 months. This will be a intent-to-treat analysis.
Clinic outcomes at multiple timepoints1-24 months• Compare clinical success rates (defined as at least 50% reduction in WOMAC) between GAE and observation at various timepoints: 1 months, 3 months, 6 months, 12 months, 24 months. This will be a per-protocol analysis.
Degree of change in clinical outcomes via WOMAC1-24 months• Compare mean decrease in WOMAC (measured by percentage) between GAE and observation at various timepoints: 1 month, 3 months, 6 months, 12 months, 24 months. This will be a per-protocol analysis.
Decrease in pain1-24 months• Compare mean decrease in pain (measured by VAS: visual analog scale) between GAE and observation at various timepoints: 1 month, 3 months, 6 months, 12 months, 24 months. This will be a per-protocol analysis.
Change in quality of life1-24 months• Compare mean improvement in health-related quality of life (measured by KOOS5) between GAE and observation at various timepoints: 1 month, 3 months, 6 months, 12 months, 24 months. This will be a per-protocol analysis.
Compare clinical success rates1-24 months• Compare clinical success rates based on varying reductions in WOMAC (16% - minimally clinically important difference, 75%, and 90%) between GAE and observation at all timepoints: 1 months, 3 months, 6 months, 12 months, 24 months. This will be a per-protocol analysis.
Incidence of treatment related adverse events0-24 months• To assess safety via tabulation of adverse events.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORSiddharth A Padia, MD

University of California, Los Angeles

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 30, 2026