Biosensors International has announced four- year results from the BioFreedom First in Man study (FIM), which demonstrated similar clinical outcomes between BioFreedomTM, a polymer-free drug-coated stent (DCS), and Boston Scientific's TaxusTM LibertéTM drug-eluting stent (DES), with no evidence of definite and/or probable stent thrombosis. Results were presented by Dr. Ricardo Costa, Instituto Dante Pazzanese de Cardiologia, Sao Paulo, Brazil, at the 25th annual Transcatheter Cardiovascular Therapeutics (TCT) meeting, sponsored by the Cardiovascular Research Foundation.
BioFreedom represents the latest development in Biosensors' stent technology, featuring a micro-structured abluminal surface which permits the controlled release of Biolimus A9TM (BA9TM) without the use of a polymer. BA9 is a highly lipophilic antirestenotic drug developed by Biosensors specifically for use with stents.
In this First in Man ('FIM') study, 182 patients were randomized into three equally sized treatment groups: BioFreedom; a low-dose formulation of BioFreedom that is not being commercialized; and Taxus Liberté. 93.5% of enrolled patients were followed up at four years.
At four years, the rate of MACE (a composite of all death, MI, emergent cardiac artery bypass graft (CABG) and target lesion revascularization (TLR)) observed in patients treated with BioFreedom was not significantly different from that observed in patients treated with Taxus Liberté (13.6% vs. 13.3%: p= non-significant (>0.05)). TLR was performed nearly half as often on patients treated with BioFreedom as on those treated with Taxus Liberté (5.2% vs. 10.2% p= non-significant (>0.05)).
BioFreedom demonstrated sustained safety up to four years, including absence of definite and/or probable stent thrombosis.
Another important trial - LEADERS FREE - has been designed to assess the potential for a DCS to deliver the anti-restenotic benefits of a DES while giving a shorter one-month course of DAPT, currently only recommended for a bare-metal stent (BMS). It is the world's first prospective, randomised double-blind trial between a DCS and BMS, exclusively involving patients at high risk of bleeding. Patients in both arms of the study are being prescribed only one month of DAPT, although they are taking a single anti-platelet drug indefinitely.
Approximately 2,500 patients are being enrolled in the study at 65 sites across Europe, Asia and South America, with follow-up scheduled for two years. 1,000 patients have been enrolled to date. Investigators anticipate completing the enrollment process by early 2014. Primary endpoint data is likely to be presented during 2015.
In January this year, BioFreedom received CE Mark approval, supported by strong primary endpoint data from the earlier-mentioned FIM study. At 12 months, BioFreedom was non- inferior (pnon-inferiority=0.001) to Taxus Liberté in terms of Late Lumen Loss, with a trend towards superiority (p=0.11). Median in-stent late lumen loss in patients receiving BioFreedom was reduced to 0.17 mm as compared with a median in-stent late lumen loss of 0.35 mm in the Taxus Liberté group.
BioFreedom is in the process of being launched in selected markets, with a full commercial launch anticipated during 2014.