International Circulation:  In other words do you think some of these trials aimed to demonstrate inferiority rather than superiority?
　　Prof David Kandzari: Indeed， there is always a succession of non-inferiority trials which can lead to new approvals. There is a concept called statistical creep whereby a succession of non inferiority trials could result in the product becoming no better than what  it was  and so we have to be very cautious this respect. It is easier to put a new stent on the market based on non inferiority. This is because to demonstrate superiority in terms of stent thrombosis and safety from these bioresorbable stents given that we are already seeing fairly low rates of thrombosis from these second generation drug eluting stents would be very difficult .
　　International Circulation: Therefore in order to demonstrate any noticeable difference we will need to design a very large trial and enrol many patients?
　　Prof David Kandzari:  Yes， by a magnitude of tens of thousands of patients and because of this issue and because of the changes of the regulatory requirements all over the world where they are being more stringent and restrictive in terms of margins of non-inferiority， it is going to take a very large trial to get a new stent onto the market.
　　International Circulation:  For these large trials do you think this will make China a more attractive option to conduct these trials?
　　Prof David Kandzari: I think there are many important points which China a very attractive option to conduct early phase and advanced stent trials. One of the reasons is that China represents a significant proportion of the population in the world and cardiovascular death is emerging as one of the leading cause of death. This alone makes evaluating new therapies and drugs attractive. Secondly， on behalf of the Chinese clinicians and investigators who are now organizing in a way that is creating a very solid infrastructure for clinical trial conduct， design and follow up. We are seeing an increasing volume of publications from China demonstrating both the systematic approach to trial design and execution as well as the credibility of the data. In the U.S for example the FDA has recognized that in order to conduct a large trial it will need to be global. We cannot conduct a trial with thirty- forty- thousand patients in the United States alone.  Therefore a more global representation is needed and certainly China represents one of the leading geographies.