(104 days)
Embozene® Microspheres are intended for embolization of arteriovenous malformations, and hypervascular tumors, including uterine fibroids.
Embozene® Microspheres are tightly calibrated, compressible microspheres intended to occlude vasculature for the purpose of blocking blood flow to a target tissue such as a hypervascular tumor (HVT) or arteriovenous malformation (AVM). Embozene® Microspheres are manufactured from sodium polymethacrylate and coated with proprietary Polyzene®-F. The microspheres are compressible to enable smooth delivery through the indicated delivery catheter. Embozene® Microspheres are color coded by size to allow easy identification of the different sizes. Embozene® Microspheres are supplied sterile and packaged in 20ml polycycloolefin syringes with a standard 7ml fill volume across the range. Embozene® Microspheres syringes or vials are available in 1 ml or 2 ml microsphere volume.
The acceptance criteria for the Embozene® Microspheres and the study demonstrating its performance are detailed below.
It's important to note that this submission relies heavily on substantial equivalence to previously cleared predicate devices, rather than establishing entirely new performance criteria through a de novo study.
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance | Study Reference |
|---|---|---|---|
| Intended Use | Embolization of arteriovenous malformations and hypervascular tumors (including uterine fibroids) | Device is intended for these uses. Specificity for uterine fibroids is the update from predicate. | Clinical experience reviewed (Smeets et al.) |
| Technological Characteristics | - Same manufacturer, classification, regulation, product codes (with added NAJ for uterine fibroids). |
- Same method of delivery, Rx status.
- Same mechanism of action (mechanical occlusion).
- Same material class, design, and composition (Crosslinked polyacrylate hydrogel with Polyzene-F).
- Same size ranges, biocompatibility, microsphere volume, sterility assurance level ($10^{-6}$), pyrogen-free status, packaging, and shelf-life (3 years). | All technological characteristics are identical to the primary predicate device (Embozene® Microspheres, K073417 and K132675). The only difference is the broadened indication for use to explicitly include uterine fibroids, which is supported by clinical data. | Non-Clinical Performance Testing (bench testing) and comparison to predicate device. |
| Safety | No unique safety concerns regarding use for uterine fibroid embolization. | Review of published and unpublished data regarding adverse events did not identify any unique safety concerns. Adverse events observed in the Smeets et al. study (hysterectomy due to incomplete fibroid expulsion or persistent pain) are documented, but not deemed "unique safety concerns" for the device itself. | Clinical Experience (Smeets et al.) |
| Clinical Effectiveness (for Uterine Fibroids) | Improvement in fibroid symptoms and/or reduction in fibroid/uterine volume, successful infarction. (Implicitly comparable to predicate device performance) | - UFS-QOL Symptom Severity Scores: Mean score dropped from 64 at baseline to 23 at 3 months (n=85), and to 16 at 12.8 months (n=81). - Fibroid/Uterine Volume Reduction: Mean dominant fibroid volume reduction of 45% at 3 months. Mean total uterine volume reduction of 42% at 3 months.
- Fibroid Infarction: 94% rate of >90% infarction of dominant fibroid at 3 months. 91% rate of >90% infarction of total fibroid load at 3 months. | Clinical Experience (Smeets et al.) |
Study Details
The submission's primary evidence for meeting acceptance criteria for the expanded indication (uterine fibroids) comes from a review of clinical information, specifically a published study by Smeets et al., and a comparison to predicate devices. No new, prospective, de novo clinical trial was conducted for this 510(k) submission.
1. A table of acceptance criteria and the reported device performance:
See table above.
2. Sample size used for the test set and the data provenance:
- Sample Size for Clinical Data:
- Smeets et al. study: n=85 patients for initial 3-month follow-up on UFS-QOL scores. n=81 patients for extended 12.8-month follow-up on UFS-QOL scores.
- Data Provenance:
- Smeets et al. study: Published data, conducted outside the United States. The document states "published and unpublished data on the use of use of Embozene® for the treatment of uterine fibroids (outside the United States)". This indicates a retrospective or prospective observational study conducted previously.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This information is not provided in the summary. The clinical study (Smeets et al.) relied on patient-reported outcomes (UFS-QOL) and objective measurements from MRI (uterine and fibroid volume, fibroid infarction). The interpretation of MRI results would have been by medical professionals (radiologists), but their number and specific qualifications are not specified in this 510(k) summary.
4. Adjudication method for the test set:
- This information is not provided in the summary. For the Smeets et al. study, it doesn't mention any specific adjudication method for patient-reported outcomes or MRI interpretations.
5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
- No, an MRMC comparative effectiveness study was not done. This device is a vascular embolization device, not an AI-assisted diagnostic tool. Therefore, the concept of "human readers improve with AI assistance" is not applicable.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- No, this is not an algorithm or AI-based device. It is a physical device (microspheres) for embolization. Therefore, standalone algorithm performance is not relevant.
7. The type of ground truth used:
- For the clinical effectiveness concerning uterine fibroids, the ground truth was established through:
- Patient-reported outcomes: Uterine Fibroid Symptom Quality of Life (UFS-QOL) instrument.
- Imaging-based objective measures: Uterine and fibroid volume reduction and percent fibroid infarction as determined by MRI.
8. The sample size for the training set:
- Not applicable / Not explicitly stated. This is not an AI/machine learning device that involves a training set in the conventional sense. The "training" for the device's effectiveness is based on the general understanding of embolization therapy and the established performance of predicate devices. The clinical data from Smeets et al. serves as evidence for effectiveness, not as a training set for an algorithm.
9. How the ground truth for the training set was established:
- Not applicable. As mentioned, there isn't a "training set" in the context of an algorithm. The evidence base relies on existing medical knowledge, predicate device performance, and clinical study outcomes.
§ 870.3300 Vascular embolization device.
(a)
Identification. A vascular embolization device is an intravascular implant intended to control hemorrhaging due to aneurysms, certain types of tumors (e.g., nephroma, hepatoma, uterine fibroids), and arteriovenous malformations. This does not include cyanoacrylates and other embolic agents, which act by polymerization or precipitation. Embolization devices used in neurovascular applications are also not included in this classification, see § 882.5950 of this chapter.(b)
Classification. Class II (special controls.) The special control for this device is the FDA guidance document entitled “Class II Special Controls Guidance Document: Vascular and Neurovascular Embolization Devices.” For availability of this guidance document, see § 870.1(e).