Abbott has commenced Absorb II clinical trial, which will investigate the safety, efficacy and performance of its Absorb bioresorbable vascular stent against its Xience Prime everolimus-eluting coronary stent system.

The CE-marked Absorb is designed to treat blocked vessels in coronary artery disease patients and then fully dissolve, leaving the vessel free of a permanent metallic implant.

The randomised, controlled and multicentre trial will enrol around 500 patients with coronary artery disease at about 40 investigational sites in Europe and New Zealand.

Patients will be randomised to receive the Absorb and Xience Prime stent systems at 2:1 ratio, with the primary endpoints of the trial designated as a change in dimension of the lumen, over time and vasomotion at the treated vessel segment.

Clinical endpoints include death, myocardial infarction, target lesion revascularisation, and scaffold/stent thrombosis.

The primary endpoint will be examined based on changes in the vessel diameter in response to a stimulus, while the clinical endpoints will be assessed at 30 and 180 days and at one, two and three years post-treatment, and the quality-of-life measures will be evaluated prior to treatment, at 180 days and at one, two and three years post-treatment.

The first patient was enrolled at King’s College Hospital in London.

Abbott Vascular chief medical officer and Medical Affairs divisional vice-president Charles Simonton said that the Absorb II trial is the first study to compare the company’s Absorb device compared to Xience Prime, a drug-eluting metallic stent, in patients with coronary artery disease.

"This is also the first trial to evaluate clinical endpoints that may be unique to a bioresorbable device, such as measuring the ability of the vessel to respond to normal blood-pressure changes. The potential to restore a treated vessel back to a more natural state will also be assessed in this trial," Simonton added.

Patrick Serruys, a professor of interventional cardiology at Erasmus University Hospital in Rotterdam, the Netherlands, said that the Absorb II trial will test unique endpoints to determine the differences between Absorb and a permanent metallic implant, which may provide an insight into the potential uses of bioresorbable technology in patients with coronary artery disease.

"Absorb has the potential to be an important advancement in the field of interventional cardiology, as clinical trials of this dissolvable device to date suggest that a permanent implant may not be needed to restore and maintain blood flow to the heart," Serruys said.

Earlier studies have shown that the Absorb device restores blood flow by opening a blocked vessel and providing support to the vessel until the device dissolves, which happens after approximately two years.