For thirty years since the invention of angioplasty, cardiologists have been using stents to repair arteries. First was the balloon stent, then the metal stent, then the drug eluting metal stent. Next it will be the bioabsorbable stent, or should I say now it is the bioabsorbable stent?
Phase I of Abbott's new ABSORB has just been published in The Lancet and the results were very successful. After two years, 30 patients that participated in the trial showed reduction in plaque, no stent thrombosis, no major cardiac events from 6 months to 2 years, and successful absorption of the stent. There was one more result and this one amazed me: the patients' coronary arteries
were virtually restored to normalcy, having regained their ability to contract and expand.
The ABSORB coronary device is made of polylactic acid, a proven biocompatible material that is commonly used in medical implants such as dissolvable sutures. The drug that is eluted by the ABSORB stent is everolimus, an immunosuppressant to prevent the body's rejection of the stent.
Not only is ABSORB the first successful bioabsorbable stent, but the imaging technology that is used to mark its progress is also new, as well as essential to the observability of ABSORB's success. Multislice CT angiography, intravascular ultrasound, and Optical Coherence Tomography (OCT), which were used to measure ABSORB's results, did not exist when stents were first invented.
ABSORB is now going into Phase II trials which will enroll about 80 patients
from European countries, Australia and New Zealand. Drug delivery and vessel support enhancements will be made to the ABSORB stents. It will be at least three years before ABSORB is market-ready.