Artzi Natalie, Tzafriri Abraham R, Faucher Keith M, Moodie Geoffrey, Albergo Theresa, Conroy Suzanne, Corbeil Scott, Martakos Paul, Virmani Renu, Edelman Elazer R
Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
Department of Anesthesiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Ann Biomed Eng. 2016 Feb;44(2):276-86. doi: 10.1007/s10439-015-1435-z. Epub 2015 Aug 28.
The long held assumption that sustained drug elution from stent coatings over weeks to months is imperative for clinical efficacy has limited the choice for stent coating materials. We developed and evaluated an omega-3 fatty acid (O3FA) based stent coating that is 85% absorbed and elutes 97% of its Sirolimus analog (Corolimus) load within 8d of implantation. O3FA coated stents sustained drug levels in porcine coronary arteries similarly to those achieved by slow-eluting durable coated Cypher Select Plus Stents and with significantly lower levels of granuloma formation and luminal stenosis. Computational modeling confirmed that diffusion and binding constants of Corolimus and Sirolimus are identical and explained that the sustained retention of Corolimus was facilitated by binding to high affinity intracellular receptors (FKBP12). First in man outcomes were positive-unlike Cypher stents where late lumen loss drops over 6 month, there was a stable effect without diminution in the presence of O3FA. These results speak to a new paradigm whereby the safety of drug eluting stents can be optimized through the use of resorbable biocompatible coating materials with resorption kinetics that coincide with the dissociation and tissue elimination of receptor-bound drug.
长期以来一直认为,支架涂层在数周甚至数月内持续释放药物对于临床疗效至关重要,这限制了支架涂层材料的选择。我们研发并评估了一种基于ω-3脂肪酸(O3FA)的支架涂层,该涂层85%被吸收,在植入后8天内可洗脱其97%的西罗莫司类似物(科罗莫司)负载量。O3FA涂层支架在猪冠状动脉中维持的药物水平与缓释耐用涂层Cypher Select Plus支架所达到的水平相似,且肉芽肿形成和管腔狭窄水平显著更低。计算模型证实,科罗莫司和西罗莫司的扩散和结合常数相同,并解释了科罗莫司的持续保留是通过与高亲和力细胞内受体(FKBP12)结合来实现的。首例人体试验结果是阳性的——与Cypher支架不同,Cypher支架的晚期管腔丢失在6个月内会下降,而在有O3FA的情况下,其效果稳定且无减弱。这些结果表明了一种新的模式,即通过使用具有与受体结合药物的解离和组织消除相匹配的吸收动力学的可吸收生物相容性涂层材料,可以优化药物洗脱支架的安全性。