Boston Scientific announced its support for the Horizons II AMI clinical trial, designed to evaluate safety and efficacy of the Promus Element plus everolimus-eluting platinum chromium (PtCr) coronary stent, versus the Omega platinum chromium bare-metal stent, in acute myocardial infarction (AMI) patients.

Horizons II AMI is a randomised double-blind superiority clinical trial that will enrol around 7,000 to 10,000 patients at up to 400 sites worldwide, to study coronary stents in heart attack patients.

The trial will compare the Promus Element stent to the Omega stent in patients undergoing primary percutaneous coronary intervention (PCI) for ST segment elevation acute myocardial infarction (STEMI).

In the study, the primary clinical endpoints will be target lesion revascularisation (TLR) and stent thrombosis at 12 months, while the non-inferiority pharmacology endpoint includes death, myocardial infarction (MI), stroke, stent thrombosis or thrombolysis in myocardial infarction (TIMI) major / minor bleeding, between one and 15 months. The company said patient enrolment in the trial is scheduled to begin in late 2012.

Horizons II AMI trial builds on data from the original Horizons AMI trial, which evaluated 3,006 patients who were randomised to receive either drug-eluting stents or bare-metal stents for the treatment of AMI.

Boston Scientific global chief medical officer Keith Dawkins said the company supported large clinical trials that provide the medical community with data that can be used in combination with broader clinical judgment to develop optimal treatment strategies for challenging patient and lesion subsets.

"We look forward to the results of this trial comparing the latest generation of drug-eluting and bare-metal stents on the advanced PtCr element platform," Dawkins added.

Principal investigator of the trial Gregg Stone said, as the largest primary PCI randomised trial ever performed in heart attack patients, Horizons II AMI is expected to provide guidance for physicians as to which stents and drugs will optimise outcomes following a heart attack.