Paclitaxel Prodrugs with Sustained Release and High Solubility in Poly(ethylene glycol)-b-poly(ε-caprolactone) Micelle Nanocarriers: Pharmacokinetic Disposition, Tolerability, and Cytotoxicity
作者:M. Laird Forrest、Jaime A. Yáñez、Connie M. Remsberg、Yusuke Ohgami、Glen S. Kwon、Neal M. Davies
DOI:10.1007/s11095-007-9451-9
日期:2008.1
Develop a Cremophor® and solvent free formulation of paclitaxel using amphiphilic block co-polymer micelles of poly(ethylene glycol)-b-poly(ɛ-caprolactone) (PEG-b-PCL) and characterize their release, solubility, cytotoxicity, tolerability, and disposition. Hydrophobic prodrugs of paclitaxel were synthesized via DCC/DMAP or anhydride chemistry to overcome the poor loading (<1% w/w) of paclitaxel in micelles of PEG-b-PCL. Micelles were prepared by a co-solvent extraction technique. A micellar formulation of paclitaxel prodrug (PAX7′C6) was dosed intravenously to rats (10 mg/kg) and compared to Taxol® (paclitaxel in CrEL:EtOH) and PAX7′C6 in CrEL:EtOH as controls at the same dose. Pharmacokinetic parameters and tissue distribution were assessed. Paclitaxel prodrugs had solubilities >5 mg/ml in PEG-b-PCL micelles. Resulting PEG-b-PCL micelles contained 17-22% w/w prodrug and were less than 50 nm in diameter. PEG-b-PCL micelles released paclitaxel prodrugs over several days, t1/2>3 d. Only the 7′derivative of paclitaxel with the shortest acylchain 7′hexonoate (PAX7′C6) maintained cytotoxic activity similar to unmodified paclitaxel. PAX7′C6 micelles demonstrated an increase in area under the curve, half-life, and mean residence time while total clearance and volume of distribution decreased. Paclitaxel prodrugs in PEG-b-PCL micelle nanocarriers augment the disposition and increase tolerability making further studies on tumor efficacy warranted.
开发一种不含克莫弗®(Cremophor®) 和溶剂的紫杉醇制剂,使用两亲性嵌段共聚物微球聚乙二醇-b-聚己内酯(PEG-b-PCL),并表征其释放、溶解性、细胞毒性、耐受性和分布。通过DCC/DMAP或酐化学合成紫杉醇的亲水性前药,以克服PEG-b-PCL微球中紫杉醇的低负荷(<1% 重量/重量)。微球通过共溶剂提取技术制备。将紫杉醇前药制剂(PAX7′C6)静脉注射给大鼠(10 mg/kg),并与泰素®(Taxol®)(紫杉醇在克莫弗®乙醇溶液中)和PAX7′C6在克莫弗®乙醇溶液中作为对照,剂量相同。评估药代动力学参数和组织分布。紫杉醇前药在PEG-b-PCL微球中的溶解度>5 mg/ml。所得PEG-b-PCL微球含有17-22% 重量/重量的前药,直径小于50 nm。PEG-b-PCL微球在几天内释放紫杉醇前药,半衰期>3天。只有具有最短酰链的7′己酸酯衍生物(PAX7′C6)保持与未修饰紫杉醇相似的细胞毒活性。PAX7′C6微球显示曲线下面积、半衰期和平均停留时间增加,而总清除率和分布容积减少。紫杉醇前药在PEG-b-PCL微球纳米载体中增强了分布并增加了耐受性,使得进一步研究肿瘤疗效值得。