Abbott presents two-year data from ABSORB

US drug major Abbott Laboratories presented two-year data from 30 patients in its ABSORB trial demonstrating that its bioabsorbable drug-eluting stent successfully treated coronary artery disease and was absorbed into the walls of treated arteries within two years, leaving behind blood vessels that appeared to move and function similar to unstented arteries, at the Cardiovascular Research Foundation's annual scientific symposium.

The ABSORB trial is a prospective, open-label study designed to enroll up to 110 patients in Belgium, Denmark, France, New Zealand, Poland and the Netherlands. Key endpoints of the study include assessments of safety - major adverse cardiac events (defined as any event that resulted in re-treatment of the treated artery, heart attack or cardiac death) and stent thrombosis (blood clot formation) rates - at 30, 180 and 270 days, with additional annual follow-up for up to five years, as well as an assessment of the acute performance of the bioabsorbable drug-eluting stent. Other key endpoints of the study include successful deployment of the bioabsorbable drug-eluting stent, follow-up measurements assessed by angiography, intravascular ultrasound (IVUS), and state-of-the-art imaging modalities at 180 days and two years.

Potential restoration of unstented artery movement to coronary blood vessels after the bioabsorbable stent was absorbed was revealed at two years with the drugs acetylcholine and nitroglycerin used in nine patients, showing vasodilation in the previously stented area, and methergine used in seven patients, showing vasoconstriction in the previously-stented area. This data shows patients experienced no stent thrombosis out to two years and no new major adverse cardiac events between six months and two years, confirming earlier one-year results. Abbott will begin enrolling the next cohort of 80 patients into the ABSORB trial in the first half of 2009.