EMEA基因毒性杂质限度指南

1、20060628 EMEA/CHMP/QWP/251344/2006基因毒性杂质限度指南(中英文对照)London, 28 June 2006CPMP/SWP/5199/02EMEA/CHMP/QWP/251344/2006The Europea n Age ncy for the Evaluatio n of Medici nal Products欧洲共同体药物评审委员会(EMEA)COMMITTEE FOR MEDICINAL PRODUCTS FOR HUMAN USE人用药品委员会(CHMP)GUIDLINE ON THE LIMITS OF GENOTOXIC IMPURITIES基

2、因毒性杂质限度指南DESCUSSION IN THE SAFETY WORKINGJune 2002-October 2002PARTY安全工作组之内的讨论TRANSMISSION TO CPMPDecember 2002CPMP传递RELEASE FOR CONSULTATIONDecember 2002专家讨论DEADLINE FOR COMMENTSMarch 2003建议收集最后期限DISCUSSION IN THE SAFETY WORKINGJune 2003-February 2004PARTY AND QUALITY WORKING PARTY安全工作组和质量工作组之间的讨论T

3、RANSMISSION TO CPMP转移给CPMPMarch 2004RE-RELEASE FOR CONSULTATION再次放行给顾问团June 2004DEADLINE FOR COMMENTS收集意见的最后期限December 2004DISCUSSION IN THE SAFETY WORKINGPARTY AND QUALITY WORKING PARTY安全工作组和质量工作组之间的讨论February 2005-May 2006ADOPTION BY CHMP被CHMP采用28 June 2006DATE FOR COMING INTO EFFECT生效日期01Ja nuary

4、 2007KEYWORDS关键词Impurities; Genotoxicity; Threshold of toxicological concern(TTC); Structure activity relationship (SAR)GUIDLINE ON THE LIMITS OF GENOTOXIC IMPURITIES基因毒性杂质限度指南TABLE OF CONTENTS 目录EXECUTIVE SUMMARY 内容摘要.INTRODUCTION 介绍32. SCOPE 范围33. LEGAL BASIS 法 律依据34. TOXICOLOGICAL BACKGROUND毒理学背景

5、45. RECOMMENDATIONS 建议45.1 Geno toxic Compo unds With Sufficie nt Evide nee for a Threshold-Related Mecha nism具有充分证据证明其阈值相关机理的基因毒性化合物 45.2 Geno toxic Compo unds Without Sufficie nt Evide nee for a Threshold-Related Mecha nism不具备充分证据支持其阈值相关机理的基因毒性化合物 55.2.1 Pharmaceutical Assessment 学评价55.2.2 Toxicol

6、ogical Assessme n毒理学评价55.2.3 Application of a Threshold of Toxicological Concern 毒理学担忧阈值应用 55.3 Decisi on Tree for Assessme nt of Acceptability of Geno toxic Impurities基因毒性杂质可接受性评价决策树 7REFERENCES.参考文献8EXECUTIVE SUMMARY 内容摘要The toxicological assessme nt of geno toxic impurities and the determ in ati

7、on of acceptable limits for such impurities in active substances is a difficult issue and not addressed in sufficient detail in the existing ICH Q3X guidances. The data set usually available for genotoxic impurities is quite variable and is the main factor that dictates the process used for the asse

8、ssme nt of acceptable limits. In the absence of data usually needed for the application of one of the established risk assessme nt methods, i.e. data from carci nogeni city Ion g-term studies or data provid ing evide nce for a threshold mecha nism of geno toxicity, impleme ntati on of a gen erally a

9、pplicable approach as defined by the Threshold of Toxicological Concern (TTC) is proposed. A TTC value of 1.5 in take of a geno toxic impurity is con sidered to be associated with an acceptable risk (excess can cer risk of <1 in 100,000 over a lifetime） for most pharmaceuticals. From this thresho

10、ld value, a permitted level in the active substa nee can be calculated based on the expected daily dose. Higher limits may be justified un der certa in con diti ons such as short-term exposure periods.基因毒性杂质的毒理学评估和这些杂质在活性药物中的可接受标准的测定是一件困难的 事情，并且在现有的ICH Q3X指南中也没有详细的规定。现有的关于基因毒性杂质的相关 数据是容易变化的，也是对杂质可接受

11、标准如何进行评价的主要影响因素。如果缺少风险评 估方法所需要的数据，比如，致癌作用的长期研究数据，或为基因毒性的阀值提供证据的数 据，一般建议使用一般通用的被定义为毒理学关注的阈值（TTC）的方法。一个“ 1$g/day ” 的TTC值，即相当于每天摄入1.5卩g的基因毒性杂质，被认为对于大多数药品来说是可以 接受的风险（一生中致癌的风险小于十万分之1）。按照这个阀值，可以根据这个预期的每日摄入量计算出活性药物中可接受的杂质水平。较高的临界值可以在特定的条件下，如短期暴 露周期等，进行推算。1. INTRODUCTION 介绍A general concept of qualification

12、 of impurities is described in the guidelines for active substances （Q3A, Impurities in New Active Substances） or medicinal products （Q3B, Impurities in New Medicinal Products）, whereby qualification is defined as the process of acquiring and evaluat ing data that establishes the biological safety o

13、f an in dividual impurity or a give n impurity profile at the level（s） specified. In the case of impurities with a geno toxic pote ntial, determ in ati on of acceptable dose levels is gen erally con sidered as a particularly critical issue, which is not specifically covered by the existing guideline

14、s.在原料药（Q3A）和药物制剂（Q3B）的杂质指导原则中，杂质限度确定的依据包括各 个杂质的生物安全性数据或杂质在某特定含量水平的研究概况。而对于遗传毒性杂质限度的确定，通常都认为是特别关键的问题，但目前尚无相关的指导原则。2. SCOPE 范围This Guideli ne describes a gen eral framework and practical approaches on how to deal with genotoxic impurities in new active substances. It also relates to new applications f

15、or existing active substa nces, where assessme nt of the route of syn thesis, process con trol and impurity profile does not provide reas on able assura nee that no new or higher levels of geno toxic impurities are in troduced as compared to products curre ntly authorised in the EU containing the sa

16、me active substa nee. The same also applies to variatio ns to exist ing Market ing Authorisati ons perta ining to the syn thesis. The guideli ne does, however, not n eed to be applied retrospectively to authorisedproducts uni ess there is a specific cause for concern.本指导原则阐述了如何处理新原料药中遗传毒性杂质的一般框架和实际方

17、法。该指导原 则也适用于已有原料药的新申请，如果其合成路线、过程控制和杂质研究尚无法确保不会产 生新的或更高含量的遗传毒性杂质(与EU目前批准的相同原料药相比)。该指导原则同样适用于已上市原料药有关合成方面的补充申请。除非有特殊原因，本指导原则不适用于已上 市的产品。In the curre nt con text the classificati on of a compo und (impurity) as geno toxic in gen eral means that there are positive findings in established in vitro or in

18、vivo genotoxicity tests with the main focus on DNA reactive substances that have a potential for direct DNA damage. Isolated in vitro findings may be assessed for in vivo releva nce in adequate follow-up test in g. In the abse nce of such in formatio n in vitro geno toxica nts are usually con sidere

19、d as presumptive in vivo mutage ns and carci nogens.目前对于基因毒性杂质的分类主要是指：在以DNA反应物质为主要研究对象的体内体外试验中，如果发现它们对 DNA有潜在的破坏性，那可称之为基因毒性。如果有足够的后 续试验，可由单独的体外试验结果，对它的体内关联性进行评估。在缺乏这样的信息时，体 外基因毒性物质经常被考虑为假定的体内诱变剂和致癌剂。3. LEGAL BASIS法规依据This guideli ne has to be read in conjun cti on with Directive 2001/83/EC (as ame n

20、ded) and all releva nt CHMP Guida nce docume nts with special emphasis on:在阅读该指南时有必要参考“Directive 2001/83/EC以及相关的CHMP指南文件，特别是以下几个指南：Impurities Testi ng Guideli ne: Impurities in New Drug Substa nces (CPMP/ICH/2737/99, ICHQ3A(R)Note for Guida nce on Impurities in New Drug Products (CPMP/ICH/2738/99, I

21、CHQ3B (R)Note for Guida nce on Impurities: Residual Solve nts (CPMP/ICH/283/95)Note for Guida nce on Geno toxicity: Guida nce on Specific Aspects of Regulatory Geno toxicity Tests for Pharmaceuticals (CPMP/ICH/141/95, ICHS2A)Note for Guida nce on Geno toxicity: A Sta ndard Battery for Geno toxicity

22、Testi ng of Pharmaceuticals (CPMP/ICH/174/95, ICHS2B)4. TOXICOLOGICAL BACKGROUND毒理学背景Accordi ng to curre nt regulatory practice it is assumed that (in vivo) geno toxic compo unds have the pote ntial to damage DNA at any level of exposure and that such damage may lead/c on tribute to tumour developme

23、 nt. Thus for geno toxic carc inogens it is prude nt to assume that there is no discer nible threshold and that any level of exposure carries a risk.根据目前的研究实践，具有(体内)遗传毒性的化合物在任何暴露量下都有可能对DNA产生损伤，而这种损伤可能会引发肿瘤。因此，对于遗传毒性致癌物质，应谨慎认为不存在 明确的阈值，任何暴露量下都存在风险。However, the existe nee of mecha ni sms lead ing to b

24、iologically mea nin gful threshold effects is in creas in gly ack no wledged also for geno toxic eve nts. This holds true in particular for compo unds in teract ing with non-DNA targets and also for pote ntial mutage ns, which are rapidly detoxified before coming in to con tact with critical targets

25、. The regulatory approach to such chemicals can be based on the ide ntificatio n of a critical no-observed-effect level (NOEL) and use of un certa inty factors.然而，对于一些遗传毒性事件，其产生生物学意义的阈值效应的机理正越来越为人所了 解。对于非DNA靶点的化合物和潜在致突变剂更是如此，因为它们在与关键靶点接触前就 已经去毒化了。对于这些化合物，研究的基础可以是确定关键的未观察到影响的剂量(NOEL)和米用不确定因子。Even for

26、 compounds which are able to react with the DNA molecule, extrapolation in a linear manner from effects in high-dose studies to very low level (huma n) exposure may not be justified due to several protective mechanisms operating effectively at low doses. However, at present it is extremely difficult

27、 to experime ntally prove the existe nee of threshold for the geno toxicity of a give n mutage n. Thus, in the abse nee of appropriate evide nee support ing the existe nee of a threshold for a genotoxic compound making it difficult to define a safe dose it is necessary to adopt a eon cept of a level

28、 of exposure that carries an acceptable risk.即使对能与DNA分子发生反应的化合物，由于低剂量时有多种有效的保护机制存在， 而不能将高剂量下的影响以线性方式外推到很低的(人)暴露水平。不过，目前要用实验方 法证明某诱变剂的遗传毒性阈值仍然非常困难。所以，在缺乏恰当的证据支持遗传毒性阈值 存在的情况下，确定安全剂量很困难，因此非常有必要采用一个可接受风险的暴露水平概念。5. RECOMMENDATIONS 建议As stated in the Q3A guideline, actual and potential impurities most lik

29、ely to arise during synthesis, purification and storage of the new drug substanee should be identified, based on a sound seie ntifie appraisal of the chemical react ions invo Ived in the syn thesis, impurities associated with raw materials that could con tribute to the impurity profile of the new dr

30、ug substa nee, and possible degradation products. This discussion can be limited to those impurities that might reas on ably be expected based on kno wledge of the chemical reacti ons and con diti ons invo Ived. Guided by existi ng geno toxicity data or the prese nee of structural alerts, pote ntial

31、 geno toxic impurities should be identified. When a potential impurity contains structural alerts, additional geno toxicity test ing of the impurity, typically in a bacterial reverse mutatio n assay, should be eonsidered (Dobo et al. 2006, M ller et ali2006). While according to the Q3A guideline suc

32、h studies can usually be eon ducted on the drug substa nee containing the impurity to be eon trolled, studies using isolated impurities are much more appropriate for this purpose and highly recomme nded.正如Q3A指导原则所述，根据合理的化学反应机理分析，在新的原料药合成、纯化和贮 存过程中很有可能产生实际的和潜在的杂质。依据现有的可能引起遗传毒性的结构”数据库，潜在的遗传毒性杂质应能被确认。如

33、果潜在的杂质含有可引起遗传毒性的结构单元，该 杂质应考虑进行遗传毒性试验(一般是细菌回复突变试验)(Dobo等，2006)。虽然Q3A指导原则认为这些研究采用含有那些需控制杂质的原料药进行是可行的，但用分离出来的杂质进行这些研究更恰当，也是高度推荐的方法。For determ in ati on of acceptable levels of exposure to geno toxic care inogens eon siderati ons of possible mecha ni sms of acti on and of the dose-resp onse relati on sh

34、ip are importa nt comp onen ts. Based on the above considerations genotoxic impurities may be distinguished into the following two classes:根据以上论述，遗传毒性杂质可以归纳成以下两类：-Geno toxic compo unds with sufficie nt (experime ntal) evide nee for a threshold-related mecha nism有充分阈值相关机理证据(实验)的遗传毒性化合物-Geno toxic com

35、po unds without sufficie nt (experime ntal) evide nee for a threshold-related mecha nism无充分阈值相关机理证据（实验）的遗传毒性化合物5.1 Genotoxic Compounds With Sufficient Evidence for a Threshold-Related Mechanism 具有充分证据证明其阈值相关机理的基因毒性化合物Examples of mecha ni sms of geno toxicity that may be dem on strated to lead to non

36、-I in ear or thresholded dose-resp onse relati on ships in clude in teracti on with the spin dle apparatus of cell division leading to aneuploidy, topoisomerase inhibition, inhibition of DNA synthesis, overloading of defe nee mecha ni sms, metabolic overload and physiological perturbati ons (e.g. i

37、nductio n of erythropoeisis, hyper- or hypothermia).非线性或阈值明确的剂量效应关系的遗传毒性机理包括：与细胞分化过程中纺锤体相互 作用；拓扑异构酶抑制；DNA合成抑制；过度的防御机制；代谢过度和生理性干扰(如诱 导红血球生成，高体温和低体温)。For (classes of) compo unds with clear evide nee for a thresholded geno toxicity, exposure levels which are without appreciable risk of geno toxicity ca

38、n be established accord ing to the procedure as outlined for class 2 solvents in the Q3C Note for Guidance on Impurities: Residual Solvents. This approach calculates a “ Permitted Daily Exposure ” (PDE), which is derived from the NOEL, or t lowestobserved effect level LOEL) in the most releva nt (an

39、i mal) study using“ un certa inty facto(UF).有明确遗传毒性阈值的化合物，不产生遗传毒性风险的暴露水平可以被确定，方法可参 照Q3C“杂质指导原则”中二类溶剂的限度确定方法。该方法可计算每日最大允许暴露量”(PDE)，数据来源于不确定因数”动物研究中的NOEL (未观察到效果的最低水平)或观察到效果的最低水平(LOEL )。5.2 Genotoxic Compounds Without Sufficient Evidence for a Threshold-RelatedMechanism不具备充分证据支持其阈值相关机理的基因毒性化合物The asse

40、ssme nt of acceptability of geno toxic impurities for which no threshold mecha ni sms are identified should include both pharmaceutical and toxicological evaluations. In general, pharmaceutical measureme nts should be guided by a policy of con trolli ng leve to “ as low as reas on ably practicable”

41、(ALARP prin ciple), where avoid ing is not possible. Levels con sideredbeing con siste nt with the ALARP prin ciple follow ing pharmaceutical assessme nt should be assessed for acceptability from a toxicological point of view (see decisi on tree & followi ng sectio ns).对于此类遗传毒性杂质，研究应包括药学和毒理学评估。总

42、之，如果杂质无法避免，药学方面的控制应遵循 合理可行的最低限量”原则（ALARP原则）。符合ALARP原则的杂质 水平再经毒理学方面的进一步评估，以验证其合理性（见决策树和以下章节）5.2.1 Pharmaceutical Assessment?学评价A specific discussion as part of the overall discussion on impurities (see Q3A(R)should be provided in the application with regard to impurities with potential genotoxicity.申

43、请材料应提供关于潜在遗传毒性杂质的特别讨论资料(见 Q3A (R)。A rati on ale of the proposed formulati on/manu facturi ng strategy should be provided based on available formulati on opti ons and tech no logies. The applica nt should highlight, withi n the chemical process and impurity profile of active substa nee, all chemical

44、substa nces, used asreage nts or prese nt as in termediates, or side-products, known as geno toxic an d/or carc inogenic (e.g.alkylat ing age nts).需要根据现在的配方选择和技术， 提供证明所选的配方/生产策略合理性的证据。申请人 应在合成工艺和杂质研究部分重点指出所有的化学物质， 包括用到的试剂、中间体、副产物, 哪些是已知遗传毒性和/或致癌性物质（如烷化剂）。More gen erally, react ing substa nces and su

45、bsta nces which show“ alerti ng structureof geno toxicity which are not shared with the active substa nee should be con sidered (see e.g. Dobo et al. 2006). Pote ntial alter natives which do no t lead to geno toxic residues in the final product, should be used if available.值得关注的是，虽然有些含有可能引起遗传毒性的结构”

46、（alerting structure）的反应试 剂与最终活性物质并没有共同结构，但也要考虑它们的遗传毒性（see e.g. Dobo et al. 2006。.如果有可能，应该对它们进行一些替代研究，以使最终产品中不会引入基因毒性残留。A justificati on n eeds to be provided that no viable alter native exists, i ncludi ng alter native routes of synthesis or formulations, different starting materials. This might for

47、 instance include cases where the structure, which is resp on sible for the geno toxic an d/or carci nogenic pote ntial is equivale nt to that n eeded in chemical syn thesis (e.g. alkylati on reactio ns).需要提供充分的论证来说明没有可行的替代方法存在，包括可替代的合成路线或配方， 不同的起始物料等。比如，应证明具有遗传毒性和/或致癌性的结构在化学合成中(如烷化反 应)是必需的。If a gen

48、otoxic impurity is considered to be unavoidable in a drug substance, technical efforts (e.g. purification steps) should be undertaken to reduce the content of the genotoxic residues in the final product in complia nce with safety n eeds or to a level as low as reas on ably practicable (see safety as

49、sessme nt). Data on chemical stability of reactive in termediates, reacta nts, and other comp onents should be in cluded in this assessme nt.如果遗传毒性杂质在原料中不可避免，则应该采取适当的技术(如纯化步骤)降低该杂 质的含量，以满足安全性要求，或符合合理可行的最低限量”原则(见安全评估)。药学评估还应包括反应中间体、反应物和其它组件等的化学稳定性研究。Detectio n an d/or qua ntificati on of these residu

50、es should be done by state-of-the-art an alytical tech niq ues.应该使用比较先进的分析检测技术来检测和量化这些残留的杂质。522 Toxicological Assessment 理学评价The impossibility of defi ning a safe exposure level (zero risk con cept) for geno toxiccarci nogens without a threshold and the realizatio n that complete elim in ati on of g

51、eno toxic impurities from drug substa nces is ofte n un achievable, requires impleme ntati on of a con cept of an acceptable risk level, i.e. an estimate of daily huma n exposure at and below which there is a n egligible risk to huma n health.鉴于在没有明确阈值的前提下定义安全暴露水平(零风险)是不可能的，且从原料药中 完全除去遗传毒性杂质经常是很难做到的

52、，所以有必要提出一个可接受风险水平”(acceptable risk leve)的概念，比如估算一个 每日最大暴露量”值，低于该暴露量时就可以 忽略其对人体健康的风险。Procedures for the derivatio n of acceptable risk levels are con sidered in the Appe ndix 3 of the Q3C Note for Guidance on Impurities: Residual Solvents for Class 1 solvents. However, these approaches require availa

53、bility of adequate data from Ion g-term carci nogeni city studies.对于可接受风险水平的推导过程请参见Q3C (杂质指南注释：一类溶液残留)中的附件三。然而，应用这些方法必须有足够多的长期致癌性研究数据。In most cases of toxicological assessme nt of geno toxic impurities on ly limited data from invitro studies with the impurity (e.g. Ames test, chromosomal aberration

54、test) are available and thus established approaches to determ ine acceptable in take levels cannot be applied. Calculati on of“ safety multiples ” from in vitro data (e.g. Ames test) are con sidered in appropriate for justificati on of acceptable limits. Moreover, n egative carc inogeni city and gen

55、o toxicity data with the drug substa nee containing the impurity at low ppm levels do not provide sufficie nt assura nee for sett ing acceptable limits for the impurity due to the lack of sensitivity of this testing approach. Even pote nt mutage ns and carc inogens are most likely to remai n un dete

56、cted whe n tested as part of the drug substa nee, i.e. at very low exposure levels. A pragmatic approach is therefore n eeded which recog ni ses that the prese nee of very low levels of geno toxic impurities is not associated with an un acceptable risk.大多数情况下，遗传毒性杂质的毒理学评估只是局限于杂质的体外研究(如Ames试验，染色体畸变试验

57、)，但这些方法并不适用于确定杂质可接受的摄入水平。也就是说，根据体 外数据(如Ames试验)计算杂质的 安全倍数(safety multiples)”、进而确定可接受的限度， 是不合适的。此外，用含有较低(ppm级)杂质水平的原料药研究其致癌性和遗传毒性，即 使得出阴性结果也不足以确保该杂质限度的合理性，因为这种试验方法缺少必要的灵敏度。 有些具有很强致突变性和致癌性物质与原料药一起进行试验时，因为在非常低的暴露水平情况下，很有可能因为低于检测限而无法检出。所以，如果认识到含量非常低的遗传毒性杂质 不存在不可接受的风险”(unacceptable risl)，那么可以采取实用的方法来控制该杂质

58、。523 Application of a Threshold of Toxicological Concent 理学相关的阈值应用A threshold of toxicological concern (TTC) has bee n developed to defi ne a com mon exposurelevel for any unstudied chemical that will not pose a risk of significant carcinogenicity or other toxic effects (Mu nro et al. 1999, Kroes and Kozia nowski 2002). This TTC value was estimated to be 1.5 卩 g/pers on /day. The TTC, origi nally developed as a“ threshold of regulati onfor food con tact materials (Rulis 1989, FDA 1995) was established based on the an alysis