Key facts

  • Medicare has no coverage policy written specifically for GAE1. Its general policy covers embolization when it is reasonable and necessary for the individual patient5.
  • Medicare has approved coverage of routine costs in some GAE device studies (for example MOTION, NCT05818150)6.
  • Some commercial insurers' policies call GAE experimental or investigational for knee arthritis pain2,3.
  • In the U.S., using GAE particles for knee pain is off-label4.
  • Evidence status as of October 2026: coverage rules can change, so check with your plan before you schedule.

Medicare and Medicare Advantage

Medicare coverage can come from a national decision by CMS, the federal agency that runs Medicare, or from local decisions by the companies that handle Medicare claims in each region. As of October 2026, the Medicare Coverage Database has no national or local coverage policy with GAE in its title1.

CMS's general policy on therapeutic embolization says embolization "is covered when done for hemorrhage, and for other conditions amenable to treatment by the procedure, when reasonable and necessary for the individual patient." It does not name GAE5. Medicare has no coverage policy written specifically for GAE, so ask your doctor's office and your plan before you schedule.

Medicare Advantage plans are run by private companies and can have their own rules, including prior approval. Ask your plan directly.

Medicare has approved coverage of routine costs in some GAE device studies (for example MOTION, NCT05818150)6,7.

Questions to ask

  • Has your office checked how my Medicare plan handles GAE?
  • Do I need prior approval, and who asks for it?
  • Will I be asked to sign a form saying I may have to pay if Medicare does not cover it?

Commercial insurance

Coverage depends on your plan. Some commercial insurers have written policies on GAE. The two current policies we checked call GAE experimental, investigational, or unproven for knee arthritis pain2,3. One of them cites a lack of evidence on long-term safety and how well it works3. Policies can change, and other plans may differ.

The Society of Interventional Radiology (SIR), by contrast, calls GAE "an established treatment option"4. Insurers and medical societies can weigh the same evidence differently. Read what studies show so far.

If a claim is denied, plans usually have an appeal process. Ask your doctor's office whether they help with prior approval and appeals.

Questions to ask

  • Does my plan have a written policy on GAE? Can I see it?
  • If my plan says no, what are my appeal options?
  • Would another treatment be covered instead?

What is the FDA status of GAE?

GAE uses tiny particles (embolic agents) that are already used in other embolization procedures. None of them has an FDA indication for knee pain yet, so in the U.S. their use for knee pain is off-label4. Off-label means a doctor uses a device for a purpose that is not on its label. Ask your doctor which particle they use and why.

Several particles have received the FDA's Breakthrough Device designation for GAE, including Embozene in October 2021, Embosphere in March 2022, and Nexsphere-F in March 20254,8. Breakthrough designation is a program for devices still being developed. It is not the same as approval for that use.

In January 2025, the maker of Nexsphere-F announced FDA permission, called an investigational device exemption, to test it for GAE in the RESORB trial9,10.

Cost questions to ask

This page does not list prices, because costs depend on your plan, where GAE is done, and whether a claim is covered. Ask your doctor's office and your plan:

  • Which codes will be billed for the procedure, the imaging, and the facility?
  • Is prior approval needed, and who requests it?
  • What would I pay if my plan covers GAE, and if it does not?
  • Will I get separate bills from the doctor, the facility, and for sedation?
  • Can I get the estimate in writing?
  • Is there a self-pay price or a payment plan?

Clinical trials as an option

Some people join a clinical trial. In a randomized trial, you may get GAE or a comparison treatment, such as a steroid injection or a sham procedure. Medicare covers routine costs in some approved device studies6. You can search registered GAE trials for knee arthritis on ClinicalTrials.gov11. Ask your doctor whether a trial could fit you.

Common questions

Does Medicare cover GAE?

Medicare has no coverage policy written specifically for GAE, so ask your doctor's office and your plan before you schedule1. Medicare has approved coverage of routine costs in some GAE device studies6.

Does insurance cover GAE?

It depends on your plan. Some commercial insurers' policies call GAE experimental or investigational for knee arthritis pain2,3. Ask your plan for its written policy and whether prior approval is needed.

Why do some insurers call GAE investigational?

One policy cites a lack of evidence on long-term safety and how well GAE works3. SIR calls GAE an established treatment option4. Insurers and medical societies weigh the same evidence differently.

What is the FDA status of GAE?

No particle used for GAE has an FDA indication for knee pain yet, so in the U.S. their use for knee pain is off-label4. Several have the FDA's Breakthrough Device designation for GAE, which is not the same as approval for that use4.

How much does GAE cost?

This page does not list prices. Costs depend on your plan, where GAE is done, and whether a claim is covered. Ask your doctor's office which codes will be billed, and ask for a written estimate.

Can I get GAE in a clinical trial?

Some GAE trials are enrolling, and some are not. Search ClinicalTrials.gov for current GAE trials for knee arthritis, and ask your doctor whether one could fit you11.

Bring questions to your visit

A printable list of questions about GAE, including coverage. Talk with your doctor about these questions.

Questions to ask before GAE

Talk with your doctor before you decide. This information does not replace personal medical advice. Read the medical disclaimer.

Sources

  1. CMS, Medicare Coverage Database (searched October 2026) ↩︎
  2. Blue Cross and Blue Shield of Texas, medical policy SUR705.048, effective July 15, 2025 ↩︎
  3. Molina Clinical Policy No. 410, genicular artery embolization of the knee for osteoarthritis ↩︎
  4. Ahmed et al., Society of Interventional Radiology position statement on genicular artery embolization, Journal of Vascular and Interventional Radiology 2026 (PMID 42118083) ↩︎
  5. CMS, National Coverage Determination 20.28, therapeutic embolization ↩︎
  6. CMS, Medicare-approved investigational device exemption (IDE) studies ↩︎
  7. ClinicalTrials.gov, MOTION randomized trial of GAE versus steroid injection (NCT05818150) ↩︎
  8. Manufacturer press release, Breakthrough Device designation for Embozene microspheres for GAE, October 13, 2021 ↩︎
  9. Manufacturer press release, investigational device exemption for Nexsphere-F and the RESORB trial, January 15, 2025 ↩︎
  10. ClinicalTrials.gov, RESORB randomized trial of GAE versus steroid injection (NCT06872567) ↩︎
  11. ClinicalTrials.gov, registered trials of genicular artery embolization for knee osteoarthritis ↩︎