卡培他滨合成路线图解

卡培他滨(capecitabine,1),化学名为5'-脱氧-5-氟-N-[(戊氧基)羰基]胞嘧啶核苷,是罗氏公司研制的5-氟尿嘧啶(5-FU)前体药物.1998年9月获美国FDA批准,临床用于治疗对紫杉醇(paclitaxel)和多柔比星(adriamycin)等药物无效的晚期原发性或转移性乳腺癌,2003年4月以相同适应症在日本上市.2001年FDA批准本品用于治疗转移性结肠直肠癌[1].     

周剂量CPT-11治疗FOLFOX治疗失败的转移性结直肠癌

目的观察和评价依立替康(CPT-11)联合5-FU/LV治疗FOLFOX治疗失败的转移性结直肠癌的疗效及不良反应。方法入组患者共34例为转移性结直肠癌,经草酸铂及5-FU/LV治疗失败后,予CPT-11 60mg/m2,LV100mg/m2,5-FU 500mg/m2,每周1次,连续3周,每4周重复。患者最多接受6个周期,每例至少2周期化疗后评价疗效。结果全组34病例均可评价。PR为5例,SD为17例,有效率14.7%(95%可信区间3.6%～34.4%),疾病控制率64.7%(95%可信区间46.8%～85.6%),平均TTP为3.5个月(范围1.5～7.5个月)。主要不良反应为白细胞减少,恶心呕吐,手足综合征及延迟性腹泻,其不良反应发生率分别为67.4%(23/34),61.8%(21/34),64.8%(22/34),38.2%(13/34),均无IV度不良反应。结论周剂量伊立替康联合5-FU/LV为草酸铂治疗失败的转移性结直肠癌挽救治疗方案,不良反应轻微,适合于曾经强烈化疗患者。     

伊立替康联合5-氟尿嘧啶/亚叶酸钙治疗晚期大肠癌的临床观察

目的:观察伊立替康(CPT-11)联合5-氟尿嘧啶(5-FU)与亚叶酸钙(CF)治疗晚期大肠癌的临床疗效和不良反应.方法:24例晚期大肠癌患者采用CPT-11 180 mg/m2,化疗第一天ivgtt 90 min;CF 100 mg/d,ivgtt,d1～5;5-FU 500 mg/m2,ivgtt,d1～5,21 d为1周期,治疗2个周期以上评价疗效.结果:24例均可评价疗效,CR 0例,PR 9例,NC 7例,PD 8例,有效率(CR PR)37.5%.中位疾病进展时间(TTP)6.7个月.不良反应主要为迟发性腹泻、中性粒细胞减少及乙酰胆碱综合征.结论:CPT-11联合5-Fu/CF治疗晚期大肠癌疗效肯定,安全性好,不良反应可耐受.可使大部分患者临床获益.     

伊立替康联合5-FU/CF治疗转移性结直肠癌46例

目的：评价伊立替康（CPT—11）联合5-FU／CF方案治疗FOLFOX4或LV5FU2方案失败的结直肠癌的客观疗效，临床受益和不良反应。方法：用CPT—11联合5-FU／CF方案治疗晚期结直肠癌患者46例，采用2周方案，即CPT—11 180mg／m^2 iv d1，CF200mg／m^2 iv d1-2，5-FU400mg iv bolusd1，5-FU600mg／m^2 iv，22hd1—2，每2周重复。观察期3—6个月。结果：完全缓解0例，部分缓解18例（有效率39．13％），稳定20例（43．47％），进展8例（17．39％）。临床受益率82．6％（19／23）。临床反应评价有效者36例（78．86％），生活质量显著提高。结论：CPT-11联合5-Fu／CF方案可作为转移性结直肠癌的二线治疗。     

抗肿瘤新药贝伐单抗的研究进展

Roche公司于2004年2月27日宣布，Genenteeh公司的贝伐单抗（rhu-Mab-VEGF，商品名：Avastin）获FDA批准上市，联合静注5-FU为基础的化疗方案，用于一线治疗初治的转移性结、直肠癌。这是世界上首次批准上市的血管内皮生长因子抑制剂。     

尿苷二磷酸葡糖醛酸转移酶*28基因多态性与FOLFIRI方案治疗晚期结直肠癌毒性的相关性分析

<正>伊立替康(CPT-11)联合5-氟尿嘧啶(5-FU)是治疗晚期结直肠癌的主要化疗方案之一。CPT-11可能引起重度迟发性腹泻和中性粒细胞减少,在欧美高加索人种应用CPT-11治疗晚期结直肠癌的研究中,3~4级不良反应的发生率为20%左右。由于对不良反应的顾虑,在我国以CPT-11为主的方案长期处于二线应用的地位。尿苷二磷酸葡糖醛酸转移酶1A1(UGT1A1)是参与CPT-     

伊立替康在大肠癌治疗中的新进展

伊立替康（camptosar,又称CPT-11）是一种有效的、具有代表性的抗肿瘤新药,它由日本研制开发,1987年开始Ⅰ期临床试验,目前该药已获美国食品和药品管理局（FDA）和欧盟的共同批准,它与奥沙利铂同为新一代抗肿瘤药物,使转移性结直肠癌的近期有效率及生存期均得到了显著提高[1]。现将CPT-11在结直肠癌新辅助治疗与辅助治疗的研究进展综述如下。     

全球医药快讯

FDA连线FDA批准regorafenib治疗转移性结直肠癌2012年9月,美国FDA批准拜耳制药公司的regorafenib用于治疗转移性结肠癌(mCRC)。本品是一种新型多激酶抑制剂,能阻断促进肿瘤生长的多种     

伊立替康联合氟尿嘧啶/亚叶酸钙治疗转移性结直肠癌

目的观察伊立替康联合亚叶酸钙及氟尿嘧啶方案治疗FOLFOX4方案失败的晚期结直肠癌的临床疗效及毒副反应。方法用CPT-11联合5-FU/CF方案治疗晚期结直肠癌患者28例,采用2周方案化疗,至少2个周期,即CPT-11180mg/m2静脉滴注,第1天;四氢叶酸200mg/m2静脉滴注,第1、2天;5-FU400mg/m2静脉推注,第1、2天;5-FU600mg/m2静脉滴注22h,第1、2天。按照WHO实体瘤近期客观疗效评定标准进行评价。结果全组28例患者均可评价疗效及不良反应。其中完全缓解0例,部分缓解10例,稳定9例,进展9例,有效率为35.7%。中位肿瘤进展时间TTP6.5个月,中位生存时间MST为12.5个月。不良反应主要是骨髓抑制,恶心、呕吐,脱发及延迟性腹泻。结论伊立替康联合5-FU/CF为二线治疗晚期结直肠癌安全有效的方案。     

FDA连线

FDA批准Zaltrap用于结肠直肠癌联合治疗 近日美国FDA批准注射用Zaltrap（Ziv—Aflibercept）可与叶酸（folinicacid）、5-氟尿嘧啶（5-fluorouracil）及伊立替康（irinotecan）联用组成化疗方案,用于对含奥沙利铂（oxaliplatin）化疗方案无应答或经含奥沙利铂化疗方案治疗后癌症恶化的转移性结肠直肠癌患者。结肠直肠癌在美国是癌症致死的第四大原因。据NIH估计,美国2012年结肠直肠癌新增病例将有143460例。     

Lessons learned from the irinotecan metabolic pathway

Irinotecan, a camptothecin analogue, is a prodrug which requires bioactivation to form the active metabolite SN-38. SN-38 acts as a DNA topoisomerase I poison. Irinotecan has been widely used in the treatment of metastatic colorectal cancer, small cell lung cancer and several other solid tumors. However, large inter-patient variability in irinotecan and SN-38 disposition, as well as severe but unpredictable diarrhea limits the clinical potential of irinotecan. Intense clinical pharmacology studies have been conducted to elucidate its complicated metabolic pathways and to provide scientific rationale in defining strategies to optimize drug therapy. Irinotecan is subjected to be shunted between CYP3A4 mediated oxidative metabolism to form two inactive metabolites APC or NPC and tissue carboxylesterase mediated hydrolysis to form SN-38 which is eventually detoxified via glucuronidation by UGT1A1 to form SN-38G. The pharmacology of this compound is further complicated by the existence of genetic inter-individual differences in activation and deactivation enzymes of irinotecan (e.g., CYP3A4, CYP3A5, UGT1A1) and sharing competitive elimination pathways with many concomitant medications, such as anticonvulsants, St. John's Wort, and ketoconazole. Efflux of the parent compound and metabolites out of cells by several drug transporters (e.g., Pgp, BCRP, MRP1, MRP2) also occurs. This review highlights the latest findings in drug activation, transport mechanisms, glucuronidation, and CYP3A-mediated drug-drug interactions of irinotecan in order to unlock some of its complicated pharmacology and to provide ideas for relevant future studies into optimization of this promising agent.     

Clinical pharmacokinetics of irinotecan-based chemotherapy in colorectal cancer patients

Irinotecan (CPT-11) significantly improves the efficacy of colorectal cancer treatment, demonstrating a superior efficacy with respect to leucovorin-modulated 5-fluorouracil (5-FU), also in fluoropyrimidine-resistant neoplasms. Preclinical studies demonstrated the inhibition of topoisomerase I by CPT-11 active metabolite 7-ethyl-10-hydroxycamptothecin (SN-38), and the possible synergistic interaction with other drugs effective against colorectal cancer, including 5-FU and oxaliplatin. Because of the occurrence of toxicities due to the large interpatient variability in drug metabolism, irinotecan is a candidate for therapeutic drug monitoring and pharmacokinetic optimisation. New schedules of drug administration (i.e. prolonged infusion) have led to improved cytotoxic effect of irinotecan, which resulted in improved overall survival and time to relapse together with reduced toxicity in comparison with 5-FU-based regimens. Furthermore, the analysis of the conversion of irinotecan into SN-38 by carboxylesterase, the detoxification of irinotecan and SN-38 by CYP3A4 and UDP-glucuronosyl transferases, and the activity of excretory systems (i.e., cMOAT, P-gp and MRP) seems able to predict the interindividual variability in pharmacokinetics and pharmacodynamics, being possible to predict untolerable toxicities. Finally, pharmacogenetics may elucidate drug interaction and gene expression modulation by irinotecan, while pharmacokinetic/pharmacodynamic models represent a valuable approach to further define the pharmacologic profile ofirinotecan and improve its therapeutic index.     

Pharmacogenetics of uridine diphosphoglucuronosyltransferase (UGT) 1A family members and its role in patient response to irinotecan

Glucuronidation, catalyzed by the glucuronosyltransferase (UGT) superfamily, is a major biotransformation pathway for several drugs, including irinotecan. Irinotecan is commonly used in colorectal cancer chemotherapy. Irinotecan undergoes metabolism in humans and is converted to its active metabolite SN-38, a topoisomerase I inhibitor. SN-38 is inactivated via glucuronidation catalyzed by various hepatic and extrahepatic UGT1A isozymes. Although the role of the UGT1A1 *28 genetic variant has received much attention in altered toxicity upon irinotecan treatment, other UGT1A enzymes also play an important role. This review summarizes pharmacokinetic, toxicologic, and pharmacogenetic studies carried out to date in irinotecan and SN-38 disposition.     

Pharmacogenetics of Uridine Diphosphoglucuronosyltransferase (UGT) 1A Family Members and its Role in Patient Response to Irinotecan

Glucuronidation, catalyzed by the glucuronosyltransferase (UGT) superfamily, is a major biotransformation pathway for several drugs, including irinotecan. Irinotecan is commonly used in colorectal cancer chemotherapy. Irinotecan undergoes metabolism in humans and is converted to its active metabolite SN-38, a topoisomerase I inhibitor. SN-38 is inactivated via glucuronidation catalyzed by various hepatic and extrahepatic UGT1A isozymes. Although the role of the UGT1A1 *28 genetic variant has received much attention in altered toxicity upon irinotecan treatment, other UGT1A enzymes also play an important role. This review summarizes pharmacokinetic, toxicologic, and pharmacogenetic studies carried out to date in irinotecan and SN-38 disposition.     

The in vitro metabolism of irinotecan (CPT-11) by carboxylesterase and beta-glucuronidase in human colorectal tumours

AIMS: Irinotecan (CPT-11) is a prodrug that is used to treat metastatic colorectal cancer. It is activated to the topoisomerase poison SN-38 by carboxylesterases. SN-38 is metabolized to its inactive glucuronide, SN-38 glucuronide. The aim of this study was to determine, the reactivation of SN-38 from SN-38 glucuronide by beta-glucuronidase may represent a significant pathway of SN-38 formation. METHODS: The production of SN-38 from irinotecan and SN-38 glucuronide (2.4, 9.6 and 19.2 microm) was measured in homogenates of human colorectal tumour, and matched normal colon mucosa from 21 patients). RESULTS: The rate of conversion of irinotecan (9.6 microm) was lower in tumour tissue than matched normal colon mucosa samples (0.30+/-0.14 pmol min-1 mg-1 protein and 0.77+/-0.59 pmol min-1 mg-1 protein, respectively; P<0.005). In contrast, no significant difference was observed in beta-glucuronidase activity between tumour and matched normal colon samples (4.56+/-6.9 pmol min-1 mg-1 protein and 3.62+/-2.95 pmol min-1 mg-1 protein, respectively, using 9.6 microm SN-38 glucuronide; P>0.05). beta-Glucuronidase activity in tumour correlated to that observed in matched normal tissue (r2>0.23, P<0.05), whereas this was not the case for carboxylesterase activity. At equal concentrations of irinotecan and SN-38 glucuronide, the rate of beta-glucuronidase-mediated SN-38 production was higher than that formed from irinotecan in both tumour and normal tissue (P<0.05). However, at concentrations that reflect the relative plasma concentrations observed in patients, the rate of SN-38 production via these two pathways was comparable. CONCLUSIONS: Tumour beta-glucuronidase may play a significant role in the exposure of tumours to SN-38 in vivo.     

Full-profile pharmacokinetics,anticancer activity and toxicity of an extended release trivalent PEGylated irinotecan prodrug

Irinotecan is an anticancer topoisomerase I inhibitor that acts as a prodrug of the active metabolite,SN-3 8.Unfortunately,the limited utility of irinotecan is attributed to its pH-dependent stability,short half-life and dose-limiting toxicity.To address this problem,a novel trivalent PEGylated prodrug(PEG-[Irinotecan]₃) has been synthesized and its full-profile pharmacokinetics,antitumor activity and toxicity compared with those of irinotecan.The results show that after intravenous a...     

Insights, challenges, and future directions in irinogenetics

Irinotecan is widely used in the treatment of metastatic colorectal cancer and extensive small-cell lung cancer. Its use is limited by severe toxicities such as neutropenia and delayed-type diarrhea. Irinotecan is converted to its active metabolite SN-38. SN-38 is further metabolized to SN-38G by various hepatic and extrahepatic UGT1A isozymes, mainly UGT1A1. Impaired glucuronidation activity of the UGT1A1 enzyme has been linked with elevated levels of SN-38, leading to toxicities. UGT1A1*28 involves an extra TA repeat in the UGT1A1 promoter region and is the variant most frequently contributing to interpatient variability in irinotecan pharmacokinetics and toxicities. This information led to the revision of the irinotecan label by the US Food and Drug Administration. Recently, UGT1A1*6 seems to contribute to the risk of toxicity of irinotecan in Asian patients. The pharmacogenetics of irinotecan (irinogenetics) is one of few promising examples of the application of pharmacogenetics to individualized drug therapy. This review summarizes ongoing studies and unanswered questions on irinogenetics.     

Effect of 5-fluorouracil treatment on SN-38 absorption from intestine in rats

5-Fluorouracil (5-FU)-based chemotherapies with irinotecan have been applied for the treatment of cancers, and a common dose-limiting toxicity is neutropenia and diarrhea. In this study, we investigated the effect of 5-FU treatment on expression levels of drug transporters for SN-38 transportation and SN-38 absorption from the intestine following 5-FU treatment. Expression levels of several drug transporters and nuclear receptors in rats after 5-FU treatment were evaluated. SN-38 absorption from the intestine was evaluated by SN-38 concentration levels in serum following SN-38 injection into the intestine of 5-FU treated rats. The levels of renal multidrug resistance protein 2 (Mrp2) on day 4 after treatment (400 mg/kg) showed significant upregulation, 359.2 ± 33.2% (mean ± S.E.) of control. Mrp2 levels in the intestine were downregulated to 26.2 ± 8.4% of control. 5-FU treatment (400 mg/kg) also significantly downregurated expression levels of P-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp) to 41.2 ± 14.7%, 15.7 ± 4.3% of control, respectively. To evaluate SN-38 absorption from the intestine, SN-38 was loaded in to the intestine on day 4 after 5-FU treatment. Pretreatment with 5-FU significantly increased SN-38 concentration in the blood 30, 60 and 90 min after SN-38 administration. The area under the curve for SN-38 in the 5-FU group was significantly higher than in vehicle groups. 5-FU treatment decreased expression levels of P-glycoprotein and Bcrp in intestine. The present study suggests that combination chemotherapy of 5-FU with irinotecan (CPT-11) may elevate SN-38 absorption from intestine.