The United States Food and Drug Administration (FDA) has approved the first fully absorbable stent to treat coronary artery disease.
Following the approval, Absorb, a bio-absorbable or dissolvable stent from US healthcare company Abbott will be finally available on home-turf. Incidentally, Absorb has been available in India over the last three-and-a-half-odd years.
And with about 18,000 Absorb stents estimated to have been used in India, it remains to be seen whether the US development could have an impact on the product use here. The product is priced a little short of Rs. 2 lakh in India.
Demand may go up
The usual practice for doctors is to look for US regulatory approvals on innovative products and with that also coming in the local demand for the dissolvable stent could increase, says an Industry insider.
A stent is a wire-like mesh that is inserted into blood vessels to remove blockages. And it has been at the heart of price control discussions in India involving medical devices.
Absorb is a break-through product in that it is absorbed into the body in about three years. The product further releases the drug everolimus to limit the growth of scar tissue, the FDA explained.
The approval of this medical device offers a new treatment option for individuals who are candidates for angioplasty, but prefer an absorbable device rather than a permanent metallic coronary stent, explained Bram Zuckerman, director of the division of cardiovascular devices at the FDA’s Center for Devices and Radiological Health.
Doctors often treat coronary artery disease with a procedure called angioplasty to widen the artery using a metal stent. Scar tissue can form within the stent causing the artery to narrow again (restenosis), the FDA said. That’s where a drug-eluting stent comes in as it temporarily releases a drug for a few months after stent placement to combat the formation of scar tissue.
Absorb is available in about 100 countries and has been used to treat more than 150,000 people with coronary artery disease worldwide, according to Abbott.
Bio-resorbable
The Absorb GT1 BVS ( bio-resorbable vascular scaffold) is manufactured from a biodegradable polymer called poly(L-lactide), similar to materials used in other types of absorbable medical devices such as sutures.
The device’s absorption by the body gradually eliminates the presence of foreign material in the artery once the stent is no longer needed. After absorption, there are only four very small platinum markers embedded in the walls of the artery, which help cardiologists identify where the Absorb GT1 BVS was originally placed, the FDA said.
The US regulatory agency evaluated data from a randomized trial of 2,008 patients, which compared the rate of major adverse cardiac events between the Absorb GT1 BVS and a drug-eluting metallic stent. After one year, the Absorb GT1 BVS group showed a major cardiac adverse event rate of 7.8 percent, which was clinically comparable to the rate of 6.1 percent observed in the control group, the FDA said.
In addition, after one year, the rate of blood clots forming within the devices was 1.54 per cent for the Absorb GT1 BVS and 0.74 per cent rate for the control.
Possible adverse events that may be associated with the procedure to insert the Absorb GT1 BVS or with the product itself include allergic reactions to materials in the device or medications used during the procedure, allergic reaction to the drug everolimus, infection or irritation at the catheter insertion site, internal bleeding, the development of abnormal connections between arteries and veins, embolism, or other coronary artery complications that may require medical intervention and that could lead to death, the agency cautioned.
The Absorb GT1 BVS is not advised for patients who have a known hypersensitivity or allergy to everolimus or the materials used in the device, such as poly(L-lactide), poly(D,L-lactide), or platinum. It is also contraindicated for those who are not candidates for angioplasty, have sensitivity to contrast, or who cannot take long-term aspirin therapy along with other blood-thinning medications (antiplatelet agents), the USFDA added.
