陸國才新藥安全藥理學(xué)研究及進(jìn)展

1、新藥安全藥理學(xué)研究與進(jìn)展,第二軍醫(yī)大學(xué)藥物安全性評價中心 陸國才 袁伯俊,,,內(nèi) 容,安全藥理學(xué)：研究藥物治療范圍內(nèi)或治療范圍以上的劑量時，潛在不期望出現(xiàn)的對生理功能的不良影響次要藥效學(xué)：主要研究藥物非期望的、與治療目的不相關(guān)的效應(yīng)和作用機(jī)制,,概 念,SFDA要求,核心組合試驗(Core Battery) 中樞神經(jīng)系統(tǒng)、心血管系統(tǒng)和呼吸系統(tǒng)研究追加的安全藥理學(xué)研究（Follow-up） 對中樞神經(jīng)系統(tǒng)、心血管系

2、統(tǒng)和呼吸系統(tǒng)進(jìn)行深入的研究 補充的安全藥理學(xué)研究（Supplemental） 研究藥物對三大系統(tǒng)以外器官(如泌尿系統(tǒng)、自主神經(jīng)系統(tǒng)、胃腸道系統(tǒng)和其它器官組織)功能的影響,,概 念,SFDA要求,確定藥物可能存在的非期望藥效作用評價藥物在毒理學(xué)和/或臨床研究中所觀察到的藥物不良反應(yīng)和/或病理生理作用研究所觀察到的和/或推測的藥物不良反應(yīng)機(jī)制,,目 的,SFDA要求,有助于了解新藥的藥理作用特點和機(jī)制有助于發(fā)現(xiàn)新藥理作用

3、，一藥多用，藥盡其用為毒理學(xué)研究打下基礎(chǔ)，是各種毒性實驗的必要補充,,目 的,SFDA要求,貫穿在新藥研究全過程中，可分階段進(jìn)行在藥物進(jìn)入臨床試驗前，應(yīng)完成Core Battery Studies追加和/或補充的安全藥理學(xué)研究可在申報生產(chǎn)前進(jìn)行,,階段性,SFDA要求,,內(nèi)容要求,SFDA要求,神經(jīng)系統(tǒng) 運動功能、行為改變、協(xié)調(diào)功能、感覺運動反射和體溫等的變化(小鼠)心血管系統(tǒng) 給藥前后血壓（包括收縮壓、舒張壓和平均

4、壓）、心電圖（包括QT間期、PR間期、ST段和QRS波等）和心率等變化(Beagle犬)呼吸系統(tǒng) 呼吸頻率和呼吸幅度(Beagle犬)根據(jù)情況增加其它系統(tǒng)或指標(biāo),1.動物選擇 可采用不同類型動物(正?；蚰Ｐ停逍鸦蚵樽?。一般多用正常動物2.劑量途徑 產(chǎn)生主要藥效作用及以上的3個劑量，臨床給藥途徑3.觀察時間 藥效學(xué)和藥代動力學(xué)特性、受試動物、臨床研究方案等因素選擇觀察時間點和觀察時間,SFDA要求,,有關(guān)問題,

5、4.系統(tǒng)指標(biāo)中樞神經(jīng)系統(tǒng)心血管系統(tǒng)呼吸系統(tǒng)根據(jù)情況增加其它系統(tǒng)或指標(biāo)5.體外研究 應(yīng)確定受試物的濃度-效應(yīng)關(guān)系。無明顯影響作用時，應(yīng)說明濃度選擇范圍,SFDA要求,,有關(guān)問題,中樞神經(jīng)系統(tǒng)：對行為、學(xué)習(xí)記憶、神經(jīng)生化、視覺、聽覺和電生理等的影響心血管系統(tǒng)：對心輸出量、心肌收縮作用、血管阻力等指標(biāo)的檢測呼吸系統(tǒng)：對氣道阻力、肺動脈壓力、血氣分析等指標(biāo)的檢測,SFDA要求,,追加安全藥理學(xué),泌尿系統(tǒng)：對腎功能的影響，如對尿

6、量、比重、滲透壓、pH、電解質(zhì)平衡、蛋白質(zhì)、細(xì)胞和血生化（如尿素氮、肌酐、蛋白質(zhì)）等指標(biāo)的檢測自主神經(jīng)系統(tǒng)：有關(guān)受體的結(jié)合、體內(nèi)或體外對激動劑或拮抗劑的功能反應(yīng)、對自主神經(jīng)的直接刺激作用和對心血管反應(yīng)、壓力反射和心率等指標(biāo)的檢測,SFDA要求,,補充安全藥理學(xué),胃腸系統(tǒng)：觀察藥物對胃腸系統(tǒng)的影響，如胃液分泌量和pH、胃腸損傷、膽汁分泌、離體回腸收縮、胃液pH等指標(biāo)的測定其它研究：潛在的依賴性、骨骼肌、免疫和內(nèi)分泌功能等的影響,SFD

7、A要求,,補充安全藥理學(xué),體內(nèi)血藥濃度低，或其它組織器官分布很少的局部用藥（如皮膚、眼科用藥）只用于治療晚期癌癥病人的細(xì)胞毒類藥物，在首次用于臨床前可不做一般藥理學(xué)研究，但不包括具有新作用機(jī)制的此類藥物,SFDA要求,,免做安全藥理學(xué),,,內(nèi) 容,“Safety pharmacology includes the assessment of effects on vital functions, such as cardiova

8、scular, central nervous system and respiratory systems, and these should be evaluated prior to human exposure.” ICH M3: Nonclinical safety studies for the conduct of human clinical trials for pharmaceuticals. (Jul

9、y 1997)Value of safety pharmacology acknowledged by regulators and sponsors,ICH要求,,ICH Guideline M3, 1997,“[Safety pharmacology studies] .. investigate the potential for undesirable pharmacological activity in appropr

10、iate animal models and, where necessary, to incorporate particular monitoring for these activities in the toxicity studies and/or clinical studies.”“.. these studies may allow for a mechanistically-based explanation of

11、 specific organ toxicities, which should be considered carefully with respect to human use and indication(s).”ICH S6 “Preclinical Safety Evaluation of Biotechnology-Derived Pharmaceuticals” (Jul

12、y 1997)Pharmacological activity in animals should be considered in toxicology and clinical studiesMechanism-based understanding of toxicities (or pharmacological activities) should be carefully considered in the risk a

13、ssessment,ICH要求,,ICH Guideline S6, 1997,“This guidance was developed to help protect clinical trial participants and patients receiving marketed products from potential adverse effects of pharmaceuticals, while avoiding

14、unnecessary use of animals and other resources.”ICH S7A “Safety Pharmacology Studies for Human Pharmaceuticals” (July 2001)Safety pharmacology studies have the potential to reduce use of animals and other r

15、esources,ICH要求,,ICH Guideline S7A, 2001,清醒動物----遙測系統(tǒng),檢測清醒狀態(tài)下、自由活動動物的安全藥理學(xué)指標(biāo) 節(jié)省動物符合動物福利要求適合不同給藥方式連續(xù)動態(tài)、長時間檢測指標(biāo),,ICH要求,,4 x 4拉丁方實驗設(shè)計,ICH要求,,4 x 8拉丁方實驗設(shè)計,ICH要求,Drug to increase gastrointestinal (GI) motilityOver 5.4 mil

16、lion prescriptions in 1996 (US)34 patients TdP, 23 long QT (1993-1996) Cardiotoxicity reported when used with Ketoconazole and/or ErythromycinCase report of 8-year old girl–intensive care,ICH要求,,Cisapride Story,ICH要求,

17、,Drug Interactions Leading to QT?,Drug to increase gastrointestinal (GI) motilityOver 5.4 million prescriptions in 1996 (US)34 patients TdP, 23 long QT 1993-1996 Cardiotoxicity reported when used with Ketoconazole and

18、/or ErythromycinCase report of 8-year old girl–intensive care4 deaths and 16 resuscitated from 1993 to 1996Drug withdrawn from US market –July, 2000,ICH要求,,Cisapride Story,FDA recommended removal of Terfenadine contai

19、ning products from the market in 01/1997FDA issued warning letter to Doctors about cardiac safety of CisapridePost-marketing surveillance became more important – Medwatch reporting systemSafety pharmacology guidances

20、were approved to look at cardiovascular, respiratory and CNS side-effects of drug candidates –ICH S7A and S7BScreening for QT prolongation is now an integral part of drug development (lead optimization to clinical),ICH要

21、求,,Regulatory Response,“The study results can be used to elucidate the mechanism of action and, when considered with other information, estimate risk for delayed ventricular repolarization and QT interval prolongation in

22、 humans.”ICH S7B: Nonclinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation) by Human Pharmaceuticals (October 2005)Mechanism of action can be a goal of studiesUse

23、 data with other data to estimate risk for QT prolongation in humans,ICH要求,ICH Guideline S7B, 2005,,Bazett: QTc = QT / RR 0.5 Fridericia: QTc = QT / RR 0.33,ICH要求,QTc Interval,,心肌動作電位時的離子通道,,ICH要求,IKr: 快速延遲整流K+電流,QT/

24、QTc Prolongation,IKr Inhibition,Delayed Ventricular Repolarization,Arrhythmia,,,ADDITIONAL RISK FACTORS,,,IKr inhibitory potency: can help predict risk of QT/QTc prolongation is a biomarker for increased risk of

25、Ventricular Arrhythmias is not a biomarker for Torsade de Pointes,ICH要求,IKr &TdP,,ICH要求,Early after-depolarization（早后去極化）? TdP,,Drug Class Date WithdrawnTerfenadineAntihistamineFeb 1998SertindoleA

26、ntipsychoticDec 1998AstemizoleAntihistamineJun 1999Grepafloxacin AntibioticNov 1999CisaprideGI ProkineticJuly 2000,ICH要求,Drugs Withdrawn for TdP risk,,采用離體動物或人體心臟細(xì)胞、培養(yǎng)心臟細(xì)胞系或克隆人離子通道的異種表達(dá)體系測定離子流在離體

27、心臟標(biāo)本進(jìn)行動作電位參數(shù)測定，或在麻醉動物中進(jìn)行能體現(xiàn)動作電位周期的特異性電生理參數(shù)檢測測定清醒或麻醉動物的ECG參數(shù)在離體心臟標(biāo)本或動物進(jìn)行致心律失常作用測定,QT間期延長非臨床研究方法,,ICH要求,,,內(nèi) 容,2009,趨勢展望,安全藥理學(xué)政策法規(guī)不斷完善,,趨勢展望,QT間期研究策略,,體外電生理IKr研究采用原代或表達(dá)的IKr通道蛋白(如由hERG編碼的蛋白)評價藥物對離子電流的影響體內(nèi)對QT的研究從體內(nèi)測定心

28、室復(fù)極化，如QT間期檢測結(jié)果進(jìn)行評價化學(xué)/藥理的分類可誘導(dǎo)人QT間期延長作用的藥物如抗精神病類藥物，組胺H-1受體拮抗劑、氟喹酮類,QT間期研究策略,,趨勢展望,追加試驗離體心臟 麻醉動物 重復(fù)給藥試驗動物種屬和性別的選擇用代謝性誘導(dǎo)劑或用拮抗劑用陽性藥和參比化合物其他通道的抑制作用在多個時間點測定電生理參數(shù)模擬病理狀況和心律失常綜合風(fēng)險評估,QT間期研究策略,,趨勢展望,計算機(jī)模擬 (in silico

29、)干細(xì)胞定向分化為心肌細(xì)胞下丘腦病理切片HERG通道體外篩選新方法熒光篩選(測量膜電位)結(jié)合試驗 (標(biāo)記的HERG通道阻滯劑，HTS)斑馬魚HTS結(jié)合藥代/藥效，研究毒理學(xué)生物標(biāo)志，預(yù)測臨床,安全藥理學(xué)研究新技術(shù)新方法,,趨勢展望,計算機(jī)模擬 (in silico)干細(xì)胞定向分化為心肌細(xì)胞下丘腦病理切片HERG通道體外篩選新方法熒光篩選(測量膜電位)結(jié)合試驗 (標(biāo)記的HERG通道阻滯劑，HTS)斑馬魚HTS結(jié)

30、合藥代/藥效，研究毒理學(xué)生物標(biāo)志，預(yù)測臨床,安全藥理學(xué)研究新技術(shù)新方法,,趨勢展望,PART I MUTAGENESIS AND MUTANTSHighly Efficient ENU Mutagenesis in ZebrafishProduction of Pseudotyped Retrovirus and the Generation of Proviral Transgenic Zebrafi

31、shUndertaking a Successful Gynogenetic Haploid Screen in ZebrafishCryopreservation and In Vitro Fertilization at the Zebrafish International Resource Center,計算機(jī)模擬 (in silico)干細(xì)胞定向分化為心肌細(xì)胞下丘腦病理切片HERG通道體外篩選新方法熒光篩選(測量膜

32、電位)結(jié)合試驗 (標(biāo)記的HERG通道阻滯劑，HTS)斑馬魚HTS結(jié)合藥代/藥效，研究毒理學(xué)生物標(biāo)志，預(yù)測臨床,安全藥理學(xué)研究新技術(shù)新方法,,趨勢展望,PART II TRANSGENESISTransient and Stable Transgenesis Using Tol2 Transposon VectorsAnalysis of Genes and Genome by the Tol2-Mediated Gene

33、and Enhancer Trap MethodsBacterial Artificial Chromosome Transgenesis for ZebrafishSimple and Efficient Transgenesis with Meganuclease Constructs in Zebrafish,計算機(jī)模擬 (in silico)干細(xì)胞定向分化為心肌細(xì)胞下丘腦病理切片HERG通道體外篩選新方法熒光篩選(測

34、量膜電位)結(jié)合試驗 (標(biāo)記的HERG通道阻滯劑，HTS)斑馬魚HTS結(jié)合藥代/藥效，研究毒理學(xué)生物標(biāo)志，預(yù)測臨床,安全藥理學(xué)研究新技術(shù)新方法,,趨勢展望,PART III TISSUE-SPECIFIC MANIPULATIONSNitroreductase-Mediated Cell Ablation in Transgenic Zebrafish EmbryosFocal

35、Electroporation in Zebrafish Embryos and LarvaeTissue Micromanipulation in Zebrafish Embryos,計算機(jī)模擬 (in silico)干細(xì)胞定向分化為心肌細(xì)胞下丘腦病理切片HERG通道體外篩選新方法熒光篩選(測量膜電位)結(jié)合試驗 (標(biāo)記的HERG通道阻滯劑，HTS)斑馬魚HTS結(jié)合藥代/藥效，研究毒理學(xué)生物標(biāo)志，預(yù)測臨床,安全藥理學(xué)研究

36、新技術(shù)新方法,,趨勢展望,PART IV ANALYZING GENE EXPRESSIONZebrafish Spotted-Microarray for Genome-Wide Expression Profiling Experiments. Part I: Array Printing and HybridizationPart II : Data Acquisition and AnalysisValidating m

37、icroRNA Target Transcripts Using Zebrafish Assays,計算機(jī)模擬 (in silico)干細(xì)胞定向分化為心肌細(xì)胞下丘腦病理切片HERG通道體外篩選新方法熒光篩選(測量膜電位)結(jié)合試驗 (標(biāo)記的HERG通道阻滯劑，HTS)斑馬魚HTS結(jié)合藥代/藥效，研究毒理學(xué)生物標(biāo)志，預(yù)測臨床,安全藥理學(xué)研究新技術(shù)新方法,,趨勢展望,PART V IMAGINGMultiple Embryo

38、Time-Lapse Imaging of Zebrafish Development Live Cell Imaging of Zebrafish LeukocytesImaging Zebrafish Embryos by Two-Photon Excitation Time-Lapse MicroscopyMorphological Analysis of the Zebrafish Digestive SystemIn

39、Toto Imaging of Embryogenesis with Confocal Time-Lapse Microscopy,High sensitivityHigh concentration in myocardium after myocardial injuryRapid release for early diagnosisLong half-life in blood for late diagnosisHi

40、gh specificityAbsent in non-myocardial tissuesNot detectable in blood of non-diseased subjects,生物標(biāo)志物,,Ideal Cardiac Biomarker,Analytical characteristicsMeasurable by cost-effective assaySimple to performRapid turnar

41、ound timeSufficient precision and truenessClinical characteristicsAbility to influence therapyAbility to improve patient outcome,生物標(biāo)志物,,Ideal Cardiac Biomarker,Biomarkers of cardiac disease,生物標(biāo)志物,趨勢展望,小 結(jié),,New, R