Abbott Pulls Bioresorbable Vascular Scaffold From European Market As FDA Investigates Blood Clot Risks

Abbott Laboratories is removing the Absorb Bioresorbable Vascular Scaffold (BVS) and Absorb GT1 BVS from most of the market in Europe, amid growing concerns over the risk of blood clots associated with the heart implants. 

The company sent an urgent field notice (PDF) to doctors in Europe on March 31, announcing that the BVS will only be available at select institutions through a clinical registry starting May 31. However, the manufacturer did not issue a BVS recall, as the devices still remain on the market and sales have not ceased in the United States.

The announcement came just a couple weeks after the FDA sent a notice to healthcare providers in the United States announcing an investigation into safety issues linked to the Abbott BVS products, after approximately 11% of recipients of the heart implants suffered major adverse cardiac events.

The dissolving stents have come under suspicion after 3-year and 2-year results from clinical trials found an increase in target lesion failure, and another clinical trial was terminated due to safety concerns over an increase in stent thrombosis.

The BVS is a surgical implant used to open coronary arteries blocked by plaque to increase blood flow to the heart. The device is implanted during an angioplasty procedure, and designed to eventually dissolve and be absorbed by the body.

Abbott’s BVS was approved by the FDA in July 2016. However, according to Abbott’s letter, two-year data from a clinical trial, known as ABSORB III, used to convince the FDA to approve the device, indicates a much higher rate of heart problems than expected. Initially, the FDA approved the device looking at only one year of clinical trial data.

The FDA notes that patients who receive coronary stents are required to take dual antiplatelet therapy, typically a combination of aspirin and Plavix, or a similar blood thinner. The agency indicates that most patients who developed blood clots within a year or being implanted with the BVS had discontinued the drug therapy.

Abbott’s letter to its customers indicated that it will review the dissolving stents next summer and that it was working with European regulatory agencies to address questions over stent thrombosis concerns.

“Limiting use to these registries will enable systemic data collection to address questions raised from recent congresses about three-year clinical data and analysis from ABSORB II regarding the frequency of scaffold thrombosis and the duration of optimal DAPT after implantation,” the Abbott letter states. “This will also help to demonstrate the impact on clinical outcomes following changes to implantation technique. These important containment measures are being undertaken in light of recent concerns over elevated rate of major adverse cardiac events, specifically, myocardial infarction and scaffold thrombosis, while we await further data to confirm whether improved implantation techniques will mitigate these higher event rates and for the evaluation of longer-term benefits associated with Absorb.”

While the FDA continues its investigation, it is advising health care providers to closely follow instructions on selecting heart vessels for BVS implants; to warn patients to be aware of any symptoms of heart problems and immediately seek medical attention; to advise patients to stick to their dual antiplatelet therapy; and to report any BVS-related adverse events to the FDA’s MedWatch adverse event reporting program.