This is a brief overview of information related to FDA's approval to market this product. See the links below to the Summary of Safety and Effectiveness Data (SSED) and product labeling for more complete information on this product, its indications for use, and the basis for FDA's approval.
Product Name: Absorb GT1™ Bioresorbable Vascular Scaffold (BVS) System
PMA Applicant: Abbott Vascular, Inc.
Address: 3200 Lakeside Drive, Santa Clara, California 95054
Approval Date: July 5, 2016
Approval Letter: http://www.accessdata.fda.gov/cdrh_docs/pdf15/P150023a.pdf
What is it? The Absorb GT1 Bioresorbable Vascular Scaffold (GT1 BVS) System is a fully absorbable stent mounted on a balloon dilatation catheter. It is made of an absorbable polymer, poly(L-lactide) (PLLA), with a thin coating of the absorbable polymer poly(D,L-lactide) (PDLLA) containing the drug everolimus. The absorbable stent contains two (2) platinum marker beads, one (1) embedded at each end. The delivery system is comparable to the one used in Abbott Vascular's XIENCE Alpine Coronary Stent System (CSS) (P110019/S066).
The absorbable stent is placed into a blood vessel (coronary artery) during angioplasty to help keep the coronary artery open. The stent dissolves and will be absorbed by the body in approximately three (3) years, leaving behind only the platinum markers.
How does it work?
- A catheter with a small balloon mounted on the end is inserted into a blood vessel in the groin or arm and advanced into a coronary artery.
- The catheter is then positioned at the narrowed portion of the artery and the balloon is inflated. As the balloon inflates, it stretches the coronary artery wall (a procedure known as balloon angioplasty).
- The balloon is then deflated, and the catheter is removed from the artery.
- The GT1 BVS delivery catheter is then positioned at the narrowing of the coronary artery. The balloon on the stent delivery catheter is inflated, which expands the stent and presses it against the coronary artery wall. This procedure may be followed by repeat balloon inflations within the stent to achieve the desired stent expansion.
- The stent remains implanted within the coronary artery to help keep the artery open.
- The drug (everolimus) is released over time into the artery wall around the stent to help prevent the vessel from re-narrowing.
- Both the PDLLA coating and the PLLA stent dissolve over time and are absorbed into the body.
When is it used? The GT1 BVS is used in patients who have a narrowing in their coronary arteries caused by coronary artery disease – a condition that occurs when the arteries that supply oxygen-rich blood and nutrients to the heart muscle become narrowed or blocked by a gradual build-up of "plaque." Plaque is made up of fatty deposits (cholesterol), white blood cells, calcium, and scar tissue that collect over time in the coronary artery wall. If these arteries become blocked or narrowed, treatment may be required to improve blood flow and increase the supply of oxygen to the heart.
The GT1 BVS is a temporary scaffold that will fully resorb over time and is to be used in patients who have a narrowing in their coronary artery lesions that is less than or equal to 24 mm long with a reference vessel diameter of ≥ 2.5 mm and ≤ 3.75 mm.
What will it accomplish? A significantly narrowed coronary artery limits blood flow to the heart muscle and can cause chest pain (angina). Placement of the GT1 BVS Stent within the narrowed coronary artery improves blood flow. After a coronary artery stent is implanted, re-narrowing of the artery may occur. The drug (everolimus) is released over time from the GT1 BVS Stent surface into the adjacent artery wall to help prevent re-narrowing of the vessel.
Absorb was studied in a large randomized clinical trial in the United States (ABSORB III) that compared Absorb with the XIENCE metallic stent. The trial enrolled 1,322 patients treated with Absorb and 686 patients treated with XIENCE. All patients will be followed for 5 years. At 1 year, the combined rate of cardiac death, heart attack associated with the vessel treated by the scaffold or stent, or retreatment of the lesion due to vessel re-narrowing was 7.8% in the Absorb group and 6.1% in the XIENCE group. The rate of blood clot formation within the scaffold or stent was 1.5% in Absorb and 0.7% in XIENCE. An additional analysis showed that the use of Absorb to treat blockages in small heart arteries was associated with an increased risk of cardiac events (primarily heart attack and blood clot formation within the scaffold) compared to treatment with the XIENCE stent. To address this issue, the instructions for use includes specific information regarding the importance of vessel sizing to identify arteries that are appropriate for Absorb implantation. Overall, clinical outcomes in the Absorb group were comparable to XIENCE, and demonstrated that the Absorb GT1 BVS is safe and effective for patients for whom the device is intended.
When should it not be used? The GT1 BVS is contraindicated for use in:
- Patients who cannot tolerate, including allergy or hypersensitivity to, procedural anticoagulation or post-procedural antiplatelet regimen.
- Patients with hypersensitivity or contraindication to everolimus or structurally-related compounds, or known hypersensitivity to scaffold components (poly(L-lactide), poly(D,L-lactide), platinum) or with contrast sensitivity.
Additional information (including warnings, precautions and adverse events): Summary of Safety and Effectiveness Data and labeling are available online.