药品信息:
--------------------------------------------------------------- 部分中文紫杉醇处方资料(仅供参考) ---------------------------------------------------------------
紫杉醇新制剂Genexol-PM获得FDA批准进行临床试验 韩国Samyang公司近日已获得美国FDA的临床研究申请(IND)批准,可以进行其新剂型的紫杉醇(Genexol-PM)的Ⅰ期临床,适应证为复发性肿瘤。病员招募工作将于今年第二季度开始。Genexol-PM的研制过程用到了Samyang公司的美国专利技术——生物降解的聚胶粒(micelle polymer)制剂技术——可以溶解疏水性的化合物,故在提高药物剂量时不会增加毒性。临床前的动物模型试验显示,Genexol-PM的最大耐受剂量是Taxol(BMS公司的紫杉醇)的40倍,即具有向肿瘤部位给予更大剂量药物的潜力。据Samyang公司说,卵巢癌和乳腺癌对Genexol-PM的应答都“极为显著”,韩国汉城国立大学进行的I期试验的初步结果显示:9例实体瘤患者(未经麻醉前用药)用药后证明该药的安全剂量达230mg/m2,且未观察到剂量限制毒性、显著的或意料外的不良反应。此聚胶粒技术还可用于其它疏水性抗癌药。
Samyang目前正在美国咨询公司GloboMax LLC的帮助下,立足美国开发Genexol-PM,其中所用的细胞培养技术由其分公司Samyang Genex提供。Samyang Genex公司位于韩国、布局精巧,操作符合GMP和美国FDA标准。目前全球紫杉醇产品的市场约为16亿美元。
胶束化紫杉醇Genexol-PM .就是这种新型纳米材料和传统抗传肿瘤药紫杉醇的完美结合。韩国Samyang 公司于1998 年开始胶束化紫杉醇Genexol-PM .的开发工作,2001 年通过 cGMP Cardinal Health 验证。目前在韩国已经基本完成临床前和临床测试,目前的数据显示:与传统的紫杉醇相比,Genexol-PM .表现出更高的人体耐受性,从而表现出更好的抗肿瘤效果,同时,副作用与紫杉醇基本相似,而传统肿瘤化疗药的最大问题就在于其高毒副作用。 该药预计将于2006 年12 月在韩国上市。同期在美国开始临床试验,预计2009 年3 月向美国FDA 提出新药申请。 (二) 市场前景紫杉醇是90 年代初上市的一种天然抗癌药,原料为“太平洋紫杉”的树皮。由于抑癌作用强,相对其他抗癌药毒性小,上市后销售情况很好,主要用途为治疗晚期卵巢癌、乳癌、非小细胞肺癌和卡波络氏肉瘤等恶性肿瘤疾病。由于紫杉醇对上述肿瘤疾病的疗效确切、副作用较小,故上市以来一直保持较高的年增长率。估计目前全球紫杉醇总销售约有10 亿美元,在植物来源的抗癌药中独占鳌头。
Samyang 公司已经被FDA 批准大规模生产紫杉醇原料药GENEXOL.,使得亚洲成为继美国、欧洲之后第三个原料药生产地。而胶束化紫杉醇Genexol-PM .作为纳米药物的前沿研究成果,相对传统紫杉醇更加具有低毒高效的特点,必然会在抗肿瘤药物市场迅速得到认可。
聚合物胶束是纳米医学发展的最新成果,它在提高药物的溶解性,稳定性和靶向性上表现出了明显的优势。胶束化紫杉醇Genexol-PM .相对于传统药物可以有效地在肿瘤内积累,效果增强,而较少地伤害人体正常组织。对于深受化疗副作用之苦的癌症患者,这无疑是一个福音。
实验室和临床试验都证明胶束化紫杉醇Genexol-PM .在各项药物指标和效果上都显示出了一定的优势,另外动物实验证明它还可以更好地阻止肿瘤在体内转移。如下图所示,与传统紫杉醇相比,Genexol-PM .给药组肿瘤在小鼠体内主要集中在原位瘤(左下),形成的转移瘤数量更少(右下)。
Samyang 公司已在美、欧、亚等世界各地申请与其相关的专利达20 多项,高技术含量带来的低毒高效是其最大竞争力所在。
Paclitaxel (TaxolTM, Bristol-Myers Squibb) has demonstrated significant activity in clinical trials against a variety of human tumors, including ovarian cancer, breast and esophageal cancer, non-small cell lung cancer, melanoma and leukemias. However, the clinical use of this promising anticancer agent is associatedwith several toxic side effects. Because of paclitaxel's poor water solubility, systemic administration of this drug relies upon concomitant use of Cremophor EL (polyoxyl 35 castor oil,USP/NF) to produce an adequately soluble formulation. Unfortunately, Cremophor EL use is also associated with patient toxicity as it is not well tolerated and leads to hypersensitivity reactions in some individuals.
To overcome these difficulties, clinicians have attempted to prolong infusion schedules or use corticosteroids and anti-histamines as a part of a premedication regimen.
However, to improve the efficacy of paclitaxel in anti-cancer therapy, a potential solution must involve reformulation of the drug into better-tolerated drug delivery vehicles.
Genexol-PM (Paclitaxel loaded polymeric micelle) parenteral formulation consists of spherical, polymeric micelles, which do not aggregate or are taken-up by reticulo-endothelial system (RES) and thus freely circulate throughout the vasculature. The need for using a cosolvent to solubilize a compound is eliminated, thereby reducing the overall toxicity of the formulation. Reducing overall toxicity potentially enables higher dose administration, which could improve therapeutic response. Eliminating the use of a cosolvent also eliminates any risk that the compound will precipitate in situ upon contact with blood, which again improves the safety profile for this drug. Some cosolvents require special administration sets to eliminate the risk of leaching plasticizer during infusion. Paclitaxel loaded polymeric micelle formulations does not require special infusion sets.
Genexol-PM is undergoing phase II human clinical investigation in USA in a selected cancer. The Korean development of Genexol-PM is progressing rapidly and three Phase II clinical studies in breast and lung cancers are expected to conclude within year 2005 with the hope product launch in year 2006.
Features Cremophor EL Free Formulation Of Paclitaxel : Free From Toxic Surfactants Easy To Reconstitute Sterile Lyophilized Formulation Fast Blood Clearance High MTD Confirmed
Advantages Low Adverse Reaction Rate Expected High Intratumor Concentration Of Paclitaxel Observed (Animal Studies) Pre-Medication May Not Be Required in All Patients
Benefits High Therapeutic Response High Safety Profile Low Growth Factor Rescue
Samyang's PM platform is a non-toxic, biodegradable polymer based system for solubilization of poorly soluble drugs Patented biodegradable di-block copolymer composed of methoxy poly(ethylene glycol)-poly(lactide) [mPEG-PLA] Core(Hydrophobic)-shell(Hydrophilic) structure High solubilizing power for hydrophobic drugs Self-forming polymeric micelles of nanometer size (ca., 10 ~ 200nm) Apparent thermodynamic stability (i.e., low CMC) In Vivo Anti-tumor Efficacy
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