TIMED BIORESORBABLE Y 90 MICROSPHERES FOR RADIOTHERAPY

定时生物可吸收微球正在研究作为运载放射性同位素，特别是Y-90的局部放射治疗。 在第一阶段制备的几种磷酸钙玻璃微球已被证明在体外保留99.0%至99.9%的钇。 它们是无毒和生物可吸收的。 这些微球在临床上使用之前必须在体内保持相似的结构完整性和钇释放特性，因为放射性从注射部位泄漏会降低治疗功效，诱导对正常组织的不期望的损伤，并增加副作用和继发性瘤形成的风险。表征Y-90在体内的释放并确定体外和体内生物再吸收速率之间的关系将为玻璃组合物优化提供有价值的输入，并将通过纳米级化学设定生物再吸收控制的标准。 一组杰出的合作者气体已经形成，导致在使用定时生物可吸收Y-90微球治疗实体瘤，关节炎关节等的安全性和有效性评价动物实验的目的是解决各种安全性问题，并提出了充分的疗效研究。 XL Sci-Tech预计将在第二阶段研究结束时生产可安全用于临床研究的定时生物可吸收Y-90微球的试验数量。拟议的商业应用：定时生物可吸收Y-90微球将提供高度局部化的β辐射，而没有放射性泄漏的风险。 这些微球对于直接瘤内注射治疗肝癌、胰腺癌等是理想的，和类风湿性关节炎的放射性滑膜切除术。

Timed-bioresorbable microspheres are being investigated as a vehicle for delivery of radioisotopes, particularly, Y-90 for localized radiotherapy. Microspheres of several calcium phosphate glasses prepared in Phase I have been shown to retain 99.0 to 99.9% of yttrium in vitro. They are non-toxic and bioresorbable. These microspheres must maintain similar structural integrity and yttrium release characteristics in vivo before they are clinically useful, since leakage of radioactivity from injection site reduces therapeutic efficacy, induces undesirable damage to normal tissues, and increases the risk of side effects and secondary neoplasia. Characterizing the release of Y-90 in vivo and identifying the relationship between in vitro and in vivo bioresorption rates will provide valuable input for glass composition optimization, and will set the criteria for bioresorption control through nano-scale chemistry. A team of distinguished collaborators gas been formed to lead in the safety and efficacy evaluations of using timed- bioresorbable Y-90 microspheres for treating solid tumors, arthritic joints, etc. Animal experiments are designed to address a variety of safety issues and adequate efficacy studies are also proposed. XL Sci-Tech expects to produce pilot quantities of timed-bioresorbable Y-90 microspheres that are safe for clinical investigations by the conclusion of the Phase II study. PROPOSED COMMERCIAL APPLICATIONS: Timed-bioresorbable Y-90 microspheres will deliver highly localized beta radiation without risk of activity leakage. These microspheres are ideal for direct intratumoral injection in treatment of cancers of liver, pancreas, etc., and radiation synovectomy of rheumatoid arthritis.