For the past three decades in Malaysia, heart disease continues to be the number one killer with about 8,000 new heart patients annually and 35% of deaths occurring in individuals aged below 60 years.
Stents are small mesh tubes used to keep narrowed arteries open for proper blood flow in patients with coronary heart disease. Over the years, Cardiology has evolved from using balloon angioplasty to drug-eluting stents, which have polymers as one of its components to control drug release.
BioFreedom™ represents the latest development in Biosensors’ stent technology, featuring a micro-structured abluminal surface, which permits the controlled release of Biolimus A9™ (BA9™) without the use of a polymer. BA9™ is a highly lipophilic antirestenotic drug, which means it dissolves in fats and prevents re-blockage in the treated arteries.
The BioFreedom™ stent offers hope to all patients, especially those at high risk of bleeding.
The roundtable session was chaired by Dato’ Dr. Rosli Mohd Ali, Head Cardiologist & Consultant Cardiologist of the National Heart Institute (IJN) and participated by cardiology experts from IJN, University Malaya Medical Centre (UMMC), HSC Medical Centre, Gleneagles Medical Centre Penang and Pantai Hospital Kuala Lumpur.
“Polymer is the lining around part of or the whole stent struts. Its function is to store the drug and elute it over the next few months. After the drug has been fully eluted, the polymer is redundant. Theoretically, it can be possibly associated with allergic reaction, which can potentially lead to blood clot formation. Prevention of blood clot formation warrants the use of dual antiplatelet agents,” said Tan Sri Dato’ Seri Dr. Robayaah Zambahari, CEO and Senior Consultant Cardiologist, National Heart Institute (IJN).
“Hence, researchers and innovators in the stent industry have developed stents with biodegradable polymer and more recently stents without polymer, with the objective of reducing the need for prolonged dual antiplatelet agents. BioFreedom™ is a polymer-free stent and therefore, theoretically may not need prolonged antiplatelet therapy. This aspect is being tested in an international multi-centre trial and we await the results,” Tan Sri Dato’ Seri Dr. Robayaah added.
Professor Wan Azman Wan Ahmad, Unit Head of Cardiology of University Malaya Medical Centre said: “Though there is a need for polymer to get the drug to the treatment site, the polymer itself has been linked to an increased risk of clotting within the stent which may occur years after the stent implantation. Therefore, patients need to be educated on why polymers are used, and how stents have evolved over the years.”
“Besides the concept of stents, general practitioners or doctors also need to understand why it is important to thin the blood when a stent is implanted using the Dual-Anti-Platelet-Therapy (DAPT), which has to be established after implanting stents to avoid a sudden blockage of the stented artery caused by clots,” said Datuk Dr. Azhari Rosman, Consultant Cardiologist, National Heart Institute (IJN).
According to Dr. Soo Chee Siong, Medical Director and Consultant Cardiologist from HSC Medical Centre, the DAPT prescription applies to all heart patients treated with stenting, and BioFreedom™ may reshape the use of DAPT in patients with complex lesions, which currently requires a longer DAPT treatment.
BioFreedom™ stents are currently undergoing a large clinical trial called LEADERS FREE, designed to assess the potential of the polymer-free drug-coated stent (DCS) in delivering the anti-restenotic benefits of a drug eluting stent whilst prescribing a shorter one-month course of DAPT, which is currently only recommended for bare-metal stents.
Approximately 2,500 patients at a high risk of bleeding are involved in this world’s first prospective, randomized double-blind trial across Europe, Asia and America.
The First in Man (FIM) demonstrated sustained safety up to four years. The goal of Leaders Free is to demonstrate BioFreedom™’s safety levels especially the need for a shorter duration of DAPT. Once this trial is published in 2015, it would then establish the safety and efficacy of BioFreedom™,” said Dato’ Dr. Rosli Mohd Ali.
“We are looking up eagerly to the results of the LEADERS FREE trial. If this trial shows to be positive, the classical bare metal stent will have a diminished use. This would indicate a major breakthrough in the field of interventional cardiology,” said Associate Professor Dr. Eric Eeckhout.
“The next generation of coronary stents should enhance patient safety by reducing stent thrombosis and duration of dual anti-platelet therapy, I think BioFreedom™ is the first of this new generation of stents, with this unique profile of just the stent and drug (termed as drug coated stent), and its unique drug releasing technology,” said Dr. Simon Lo.
Dr. Yee Kok Meng, a Consultant Interventional Cardiologist from Pantai Hospital Kuala Lumpur approaches his patients with balanced treatment and is positive about using BioFreedom™.
“I am glad to have BioFreedom™ as a stent option for my patients, as sometimes it is important to have a shorter duration of DAPT. However, it may be a challenge to educate the public and doctors at this stage as the final results of the trial are still pending,” said Dr. Yee.
According to Dr. Ramesh Singh, Interventional Cardiologist from University Malaya Medical Centre, he is glad to introduce BioFreedom™ to a wide range of patients including high-risk patients as this is a new and novel technology that has long-term promising results.