FDA Warns of Heart Risks with Abbott Absorb Bioresorbable StentMar 24, 2017
FDA Says Absorb Stent has Higher Rate of Cardiac Events
The U.S. Food and Drug Administration (FDA) has issued a safety alert warning that the Absorb GT1 Bioresorbable Vascular Scaffold (BVS), a bioresorbable stent manufactured by Abbott Vascular, is associated with an increased rate of cardiac events compared to a metal stent. Heart risks include adverse events such as cardiac death, heart attack, and the need for an additional procedure to re-open the heart vessel.
Parker Waichman LLP has decades of experience in medical device injury litigation and keeps up-to-date with drug and medical device safety news. The firm continues to offer free legal consultations to individuals with questions about filing an Absorb GT1 Bioresorbable Vascular Scaffold (BVS) lawsuit.
According to a Mar. 18, 2017 safety alert posted on the FDA website, patients with the BVS have higher rates of cardiac events compared to those with an already-approved Abbott metal stent (called the XCIENCE). The agency cited two-year data from the ABSORB III clinical trial, which found that the Absorb stent was associated with an 11 percent increased risk of major cardiac events compared to 7.9 percent in patients with the XCIENCE.
Additionally, the FDA also identified a higher incidence of blood clots in patients the Absorb, which was associated with a 1.9 percent increased risk. Comparatively, the metallic stent was associated with a 0.8 percent increased risk of blood clots.
In a letter to healthcare professionals, the FDA said "The FDA is informing health care providers treating patients with Absorb GT1 Bioresorbable Vascular Scaffold (BVS) that there is an increased rate of major adverse cardiac events observed in patients receiving the BVS, when compared to patients treated with the approved metallic XIENCE drug-eluting stent."
Regulators said the cardiac events were more likely to occur when the BVS is used in smaller arteries. The notification states, "These observed higher adverse cardiac event rates in BVS patients were more likely when the device was placed in small heart vessels,"
"The FDA is working with Abbott Vascular, Inc. to conduct additional analyses to better understand the cause(s) of the higher cardiac event and device thrombosis rates in patients treated with BVS compared to the XIENCE stent," the agency said. "The FDA will continue to monitor the performance of the BVS in ongoing clinical studies and in reports submitted to FDA through MedWatch. We will update this communication when additional information or analyses become available.
According to the FDA safety announcement, patients with the Abbott Absorb stent should seek medical attention if they have symptoms of cardiac events, including:
- irregular heartbeats
- chest pain
- shortness of breath
Abbott presented ABSORB III clinical trial data at the American College of Cardiology meeting in Washington, D.C., Fierce Biotech reports. When comparing rates of target lesion failure (TLF) between the Absorb and the XCIENCE, the company found "no statistically significant difference." TLF was measured in rates of cardiac adverse events; the rate was 3.7 percent for Absorb compared to 2.5 percent for XIENCE.
At the ACC meeting, E. Magnus Ohman, MBBS, of Duke Clinical Research Institute in Durham, N.C., commented to MedPage Today "This is somewhat surprising in one level because most of us had been enthusiastic about using bioabsorbable scaffolding to remove that permanent metallic stent in our vessels,"
"Interventional cardiology is fascinating in that it takes two steps forward and then usually one back."
"In this particular case, it may have been that high-pressure delivery of the bioabsorbable stents, that was not traditionally done, in this trial may actually play out to be really important," said Ohman. "But I also think that it's up to the ABSORB investigators that the newer technology, the better use of imaging, and those really make a difference. Because we know this is occurring on the background of dual antiplatelet therapy, which is obviously why there is some concern."
One doctor, Deepak Bhatt, MD, MPH, of Brigham and Women's Hospital, noted that early clinical suggested that the Absorb may present a higher risk of stent-related blood clots. According to Medpage Today, Dr. Bhatt said it was challenging to support the use of Absorb over the metal XIENCE stent at this time, since evidence suggests that the metallic stent is safer and more cost effective.
"The FDA's letter to healthcare providers emphasizes the importance of following instructions for use when implanting Absorb," Abbott Vascular said in an emailed statement to Medpage Today. "When implanted in appropriately-sized vessel sizes and following current instructions for use, the results for Absorb are comparable to the leading metallic drug-eluting stent - with the added feature of leaving no metal behind once it dissolves."
Abbott Absorb BVS Background
The BVS is a stent, a type of medical device used to hold up the artery in patients with heart disease, in which cholesterol builds up in the walls of arteries and impedes blood flow. The BVS is bioresorbable, meaning it is absorbed by the body after the patient heals; this occurs roughly three years after the stent is implanted.
The BVS should not be used in very small arteries, the instructions state.
The FDA approved the BVS based on one-year data from the ABSORB III clinical trial, which contained 2,008 patients in the United States. The device was cleared under the condition that Abbott Vascular conduct follow-up on these patients for another five years.
According to device instructions, adverse events associated with the BVS may include hypotention/hypertension, infection, nausea and vomiting, palpitations, dizziness, syncope, chest pain, fever, pain and death.
BVS complications may include allergic reactions, vascular complications, pericardial complications, cardiac arrhythmias and other cardiac risks, stroke, system organ failures and blood cell disorders, among other things.
Filing an Absorb GT1 Bioresorbable Vascular Scaffold Lawsuit
Parker Waichman has years of experience representing clients in medical device injury lawsuits. If you or someone you know is interested in filing an Absorb bioabsorbable stent lawsuit against Abbott, contact one of our experienced product liability lawyers today. Our firm offers free, no-obligation case evaluations. For more information, fill out our online form or call 1-800-YOURLAWYER (1-800-968-7529).