EMEA基因毒性雜質(zhì)限度指南

1、20060628 EMEA/CHMP/QWP/251344/2006基因毒性雜質(zhì)限度指南（中英文對(duì)照）London, 28 June 2006CPMP/SWP/5199/02EMEA/CHMP/QWP/251344/2006The European Agency for the Evaluation of Medicinal Products歐洲共同體藥物評(píng)審委員會(huì)(EMEA)COMMITTEE FOR MEDICINAL PRODUCTS FOR HUMAN USE人用藥品委員會(huì)(CHMP) GUIDLINE ON THE LIMITS OF GENOTOXIC IMPURITIES基因毒性

2、雜質(zhì)限度指南 DESCUSSION IN THE SAFETY WORKING PARTY安全工作組之內(nèi)的討論June 2002-October 2002TRANSMISSION TO CPMPCPMP傳遞December 2002RELEASE FOR CONSULTATION專家討論December 2002DEADLINE FOR COMMENTS建議收集最后期限March 2003DISCUSSION IN THE SAFETY WORKING PARTY AND QUALITY WORKING PARTY安全工作組和質(zhì)量工作組之間的討論June 2003-February 2004T

3、RANSMISSION TO CPMP轉(zhuǎn)移給CPMPMarch 2004RE-RELEASE FOR CONSULTATION再次放行給顧問團(tuán)June 2004DEADLINE FOR COMMENTS收集意見的最后期限D(zhuǎn)ecember 2004DISCUSSION IN THE SAFETY WORKING PARTY AND QUALITY WORKING PARTY安全工作組和質(zhì)量工作組之間的討論February 2005-May 2006ADOPTION BY CHMP被CHMP采用28 June 2006DATE FOR COMING INTO EFFECT生效日期01January

4、 2007 KEYWORDS關(guān)鍵詞Impurities; Genotoxicity; Threshold of toxicological concern (TTC); Structure activity relationship (SAR)GUIDLINE ON THE LIMITS OF GENOTOXIC IMPURITIES基因毒性雜質(zhì)限度指南 TABLE OF CONTENTS 目錄EXECUTIVE SUMMARY 內(nèi)容摘要. 31. INTRODUCTION 介紹. 32. SCOPE 范圍 . 33. LEGAL BASIS法 律依據(jù). 34. TOXICOLOGICAL B

5、ACKGROUND 毒理學(xué)背景. 45. RECOMMENDATIONS 建議. 45.1 Genotoxic Compounds With Sufficient Evidence for a Threshold-Related Mechanism具有充分證據(jù)證明其閾值相關(guān)機(jī)理的基因毒性化合物. 45.2 Genotoxic Compounds Without Sufficient Evidence for a Threshold-Related Mechanism不具備充分證據(jù)支持其閾值相關(guān)機(jī)理的基因毒性化合物. 55.2.1 Pharmaceutical Assessment藥學(xué)評(píng)價(jià). 5

6、5.2.2 Toxicological Assessment毒理學(xué)評(píng)價(jià). 55.2.3 Application of a Threshold of Toxicological Concern 毒理學(xué)擔(dān)憂閾值應(yīng)用. 55.3 Decision Tree for Assessment of Acceptability of Genotoxic Impurities基因毒性雜質(zhì)可接受性評(píng)價(jià)決策樹. 7REFERENCES. 參考文獻(xiàn). 8EXECUTIVE SUMMARY 內(nèi)容摘要The toxicological assessment of genotoxic impurities and the

7、 determination 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

8、for the assessment of acceptable limits. In the absence of data usually needed for the application of one of the established risk assessment methods, i.e. data from carcinogenicity long-term studies or data providing evidence for a threshold mechanism of genotoxicity, implementation of a generally a

9、pplicable approach as defined by the Threshold of Toxicological Concern (TTC) is proposed. A TTC value of 1.5 g/day intake of a genotoxic impurity is considered to be associated with an acceptable risk (excess cancer risk of <1 in 100,000 over a lifetime) for most pharmaceuticals. From this thres

10、hold value, a permitted level in the active substance can be calculated based on the expected daily dose. Higher limits may be justified under certain conditions such as short-term exposure periods.基因毒性雜質(zhì)的毒理學(xué)評(píng)估和這些雜質(zhì)在活性藥物中的可接受標(biāo)準(zhǔn)的測(cè)定是一件困難的事情，并且在現(xiàn)有的ICH Q3X指南中也沒有詳細(xì)的規(guī)定?，F(xiàn)有的關(guān)于基因毒性雜質(zhì)的相關(guān)數(shù)據(jù)是容易變化的，也是對(duì)雜質(zhì)可接受標(biāo)準(zhǔn)如何進(jìn)

11、行評(píng)價(jià)的主要影響因素。如果缺少風(fēng)險(xiǎn)評(píng)估方法所需要的數(shù)據(jù)，比如，致癌作用的長期研究數(shù)據(jù)，或?yàn)榛蚨拘缘拈y值提供證據(jù)的數(shù)據(jù)，一般建議使用一般通用的被定義為毒理學(xué)關(guān)注的閾值（TTC）的方法。一個(gè)“1.5g/day”的TTC值，即相當(dāng)于每天攝入1.5g的基因毒性雜質(zhì)，被認(rèn)為對(duì)于大多數(shù)藥品來說是可以接受的風(fēng)險(xiǎn)（一生中致癌的風(fēng)險(xiǎn)小于十萬分之1）。按照這個(gè)閥值，可以根據(jù)這個(gè)預(yù)期的每日攝入量計(jì)算出活性藥物中可接受的雜質(zhì)水平。較高的臨界值可以在特定的條件下，如短期暴露周期等，進(jìn)行推算。1. INTRODUCTION 介紹A general concept of qualification of impuriti

12、es 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 evaluating data that establishes the biological safety of an individu

13、al impurity or a given impurity profile at the level(s) specified. In the case of impurities with a genotoxic potential, determination of acceptable dose levels is generally considered as a particularly critical issue, which is not specifically covered by the existing guidelines.在原料藥（Q3A）和藥物制劑（Q3B）的

14、雜質(zhì)指導(dǎo)原則中，雜質(zhì)限度確定的依據(jù)包括各個(gè)雜質(zhì)的生物安全性數(shù)據(jù)或雜質(zhì)在某特定含量水平的研究概況。而對(duì)于遺傳毒性雜質(zhì)限度的確定，通常都認(rèn)為是特別關(guān)鍵的問題，但目前尚無相關(guān)的指導(dǎo)原則。 2. SCOPE 范圍This Guideline describes a general framework and practical approaches on how to deal with genotoxic impurities in new active substances. It also relates to new applications for existing active subst

15、ances, where assessment of the route of synthesis, process control and impurity profile does not provide reasonable assurance that no new or higher levels of genotoxic impurities are introduced as compared to products currently authorised in the EU containing the same active substance. The same also

16、 applies to variations to existing Marketing Authorisations pertaining to the synthesis. The guideline does, however, not need to be applied retrospectively to authorised products unless there is a specific cause for concern.本指導(dǎo)原則闡述了如何處理新原料藥中遺傳毒性雜質(zhì)的一般框架和實(shí)際方法。該指導(dǎo)原則也適用于已有原料藥的新申請(qǐng)，如果其合成路線、過程控制和雜質(zhì)研究尚無法確保

17、不會(huì)產(chǎn)生新的或更高含量的遺傳毒性雜質(zhì)（與EU目前批準(zhǔn)的相同原料藥相比）。該指導(dǎo)原則同樣適用于已上市原料藥有關(guān)合成方面的補(bǔ)充申請(qǐng)。除非有特殊原因，本指導(dǎo)原則不適用于已上市的產(chǎn)品。In the current context the classification of a compound (impurity) as genotoxic in general means that there are positive findings in established in vitro or in vivo genotoxicity tests with the main focus on DNA r

18、eactive substances that have a potential for direct DNA damage. Isolated in vitro findings may be assessed for in vivo relevance in adequate follow-up testing. In the absence of such information in vitro genotoxicants are usually considered as presumptive in vivo mutagens and carcinogens.目前對(duì)于基因毒性雜質(zhì)的

19、分類主要是指：在以DNA反應(yīng)物質(zhì)為主要研究對(duì)象的體內(nèi)體外試驗(yàn)中，如果發(fā)現(xiàn)它們對(duì)DNA有潛在的破壞性，那可稱之為基因毒性。如果有足夠的后續(xù)試驗(yàn)，可由單獨(dú)的體外試驗(yàn)結(jié)果，對(duì)它的體內(nèi)關(guān)聯(lián)性進(jìn)行評(píng)估。在缺乏這樣的信息時(shí)，體外基因毒性物質(zhì)經(jīng)常被考慮為假定的體內(nèi)誘變劑和致癌劑。3. LEGAL BASIS 法規(guī)依據(jù)This guideline has to be read in conjunction with Directive 2001/83/EC (as amended) and all relevant CHMP Guidance documents with special emphasis o

20、n:在閱讀該指南時(shí)有必要參考“Directive 2001/83/EC”以及相關(guān)的CHMP指南文件，特別是以下幾個(gè)指南：Impurities Testing Guideline: Impurities in New Drug Substances (CPMP/ICH/2737/99, ICHQ3A(R)Note for Guidance on Impurities in New Drug Products (CPMP/ICH/2738/99, ICHQ3B (R)Note for Guidance on Impurities: Residual Solvents (CPMP/ICH/283/9

21、5)Note for Guidance on Genotoxicity: Guidance on Specific Aspects of Regulatory Genotoxicity Tests for Pharmaceuticals (CPMP/ICH/141/95, ICHS2A)Note for Guidance on Genotoxicity: A Standard Battery for Genotoxicity Testing of Pharmaceuticals (CPMP/ICH/174/95, ICHS2B)4. TOXICOLOGICAL BACKGROUND 毒理學(xué)背景

22、According to current regulatory practice it is assumed that (in vivo) genotoxic compounds have the potential to damage DNA at any level of exposure and that such damage may lead/contribute to tumour development. Thus for genotoxic carcinogens it is prudent to assume that there is no discernible thre

23、shold and that any level of exposure carries a risk.根據(jù)目前的研究實(shí)踐，具有（體內(nèi)）遺傳毒性的化合物在任何暴露量下都有可能對(duì)DNA產(chǎn)生損傷，而這種損傷可能會(huì)引發(fā)腫瘤。因此，對(duì)于遺傳毒性致癌物質(zhì)，應(yīng)謹(jǐn)慎認(rèn)為不存在明確的閾值，任何暴露量下都存在風(fēng)險(xiǎn)。However, the existence of mechanisms leading to biologically meaningful threshold effects is increasingly acknowledged also for genotoxic events. This

24、holds true in particular for compounds interacting with non-DNA targets and also for potential mutagens, which are rapidly detoxified before coming into contact with critical targets. The regulatory approach to such chemicals can be based on the identification of a critical no-observed-effect level

25、(NOEL) and use of uncertainty factors.然而，對(duì)于一些遺傳毒性事件，其產(chǎn)生生物學(xué)意義的閾值效應(yīng)的機(jī)理正越來越為人所了解。對(duì)于非DNA靶點(diǎn)的化合物和潛在致突變劑更是如此，因?yàn)樗鼈冊(cè)谂c關(guān)鍵靶點(diǎn)接觸前就已經(jīng)去毒化了。對(duì)于這些化合物，研究的基礎(chǔ)可以是確定關(guān)鍵的未觀察到影響的劑量（NOEL）和采用不確定因子。Even for compounds which are able to react with the DNA molecule, extrapolation in a linear manner from effects in high-dose studies

26、 to very low level (human) exposure may not be justified due to several protective mechanisms operating effectively at low doses. However, at present it is extremely difficult to experimentally prove the existence of threshold for the genotoxicity of a given mutagen. Thus, in the absence of appropri

27、ate evidence supporting the existence of a threshold for a genotoxic compound making it difficult to define a safe dose it is necessary to adopt a concept of a level of exposure that carries an acceptable risk.即使對(duì)能與DNA分子發(fā)生反應(yīng)的化合物，由于低劑量時(shí)有多種有效的保護(hù)機(jī)制存在，而不能將高劑量下的影響以線性方式外推到很低的（人）暴露水平。不過，目前要用實(shí)驗(yàn)方法證明某誘變劑的遺傳毒性

28、閾值仍然非常困難。所以，在缺乏恰當(dāng)?shù)淖C據(jù)支持遺傳毒性閾值存在的情況下，確定安全劑量很困難，因此非常有必要采用一個(gè)可接受風(fēng)險(xiǎn)的暴露水平概念。5. RECOMMENDATIONS 建議As stated in the Q3A guideline, actual and potential impurities most likely to arise during synthesis, purification and storage of the new drug substance should be identified, based on a sound scientific apprai

29、sal of the chemical reactions involved in the synthesis, impurities associated with raw materials that could contribute to the impurity profile of the new drug substance, and possible degradation products. This discussion can be limited to those impurities that might reasonably be expected based on

30、knowledge of the chemical reactions and conditions involved. Guided by existing genotoxicity data or the presence of structural alerts, potential genotoxic impurities should be identified. When a potential impurity contains structural alerts, additional genotoxicity testing of the impurity, typicall

31、y in a bacterial reverse mutation assay, should be considered (Dobo et al. 2006, Müller et al. 2006). While according to the Q3A guideline such studies can usually be conducted on the drug substance containing the impurity to be controlled, studies using isolated impurities are much more approp

32、riate for this purpose and highly recommended.正如Q3A指導(dǎo)原則所述，根據(jù)合理的化學(xué)反應(yīng)機(jī)理分析，在新的原料藥合成、純化和貯存過程中很有可能產(chǎn)生實(shí)際的和潛在的雜質(zhì)。依據(jù)現(xiàn)有的“可能引起遺傳毒性的結(jié)構(gòu)”數(shù)據(jù)庫，潛在的遺傳毒性雜質(zhì)應(yīng)能被確認(rèn)。如果潛在的雜質(zhì)含有可引起遺傳毒性的結(jié)構(gòu)單元，該雜質(zhì)應(yīng)考慮進(jìn)行遺傳毒性試驗(yàn)（一般是細(xì)菌回復(fù)突變?cè)囼?yàn)）（Dobo等，2006）。雖然Q3A指導(dǎo)原則認(rèn)為這些研究采用含有那些需控制雜質(zhì)的原料藥進(jìn)行是可行的，但用分離出來的雜質(zhì)進(jìn)行這些研究更恰當(dāng)，也是高度推薦的方法。For determination of acceptabl

33、e levels of exposure to genotoxic carcinogens considerations of possible mechanisms of action and of the dose-response relationship are important components. Based on the above considerations genotoxic impurities may be distinguished into the following two classes:根據(jù)以上論述，遺傳毒性雜質(zhì)可以歸納成以下兩類：- Genotoxic

34、compounds with sufficient (experimental) evidence for a threshold-related mechanism有充分閾值相關(guān)機(jī)理證據(jù)（實(shí)驗(yàn)）的遺傳毒性化合物- Genotoxic compounds without sufficient (experimental) evidence for a threshold-related mechanism無充分閾值相關(guān)機(jī)理證據(jù)（實(shí)驗(yàn)）的遺傳毒性化合物5.1 Genotoxic Compounds With Sufficient Evidence for a Threshold-Related

35、Mechanism 具有充分證據(jù)證明其閾值相關(guān)機(jī)理的基因毒性化合物Examples of mechanisms of genotoxicity that may be demonstrated to lead to non-linear or thresholded dose-response relationships include interaction with the spindle apparatus of cell division leading to aneuploidy, topoisomerase inhibition, inhibition of DNA synthes

36、is, overloading of defence mechanisms, metabolic overload and physiological perturbations (e.g. induction of erythropoeisis, hyper- or hypothermia).非線性或閾值明確的劑量效應(yīng)關(guān)系的遺傳毒性機(jī)理包括：與細(xì)胞分化過程中紡錘體相互作用；拓?fù)洚悩?gòu)酶抑制；DNA合成抑制；過度的防御機(jī)制；代謝過度和生理性干擾（如誘導(dǎo)紅血球生成，高體溫和低體溫）。For (classes of) compounds with clear evidence for a thres

37、holded genotoxicity, exposure levels which are without appreciable risk of genotoxicity can be established according 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

38、derived from the NOEL, or the lowestobserved effect level (LOEL) in the most relevant (animal) study using “uncertainty factors” (UF).有明確遺傳毒性閾值的化合物，不產(chǎn)生遺傳毒性風(fēng)險(xiǎn)的暴露水平可以被確定，方法可參照Q3C“雜質(zhì)指導(dǎo)原則”中二類溶劑的限度確定方法。該方法可計(jì)算 “每日最大允許暴露量”（PDE），數(shù)據(jù)來源于 “不確定因數(shù)”動(dòng)物研究中的NOEL（未觀察到效果的最低水平）或觀察到效果的最低水平（LOEL）。5.2 Genotoxic Compounds W

39、ithout Sufficient Evidence for a Threshold-Related Mechanism 不具備充分證據(jù)支持其閾值相關(guān)機(jī)理的基因毒性化合物The assessment of acceptability of genotoxic impurities for which no threshold mechanisms are identified should include both pharmaceutical and toxicological evaluations. In general, pharmaceutical measurements shou

40、ld be guided by a policy of controlling levels to “as low as reasonably practicable” (ALARP principle), where avoiding is not possible. Levels considered being consistent with the ALARP principle following pharmaceutical assessment should be assessed for acceptability from a toxicological point of v

41、iew (see decision tree & following sections).對(duì)于此類遺傳毒性雜質(zhì)，研究應(yīng)包括藥學(xué)和毒理學(xué)評(píng)估?？傊?，如果雜質(zhì)無法避免，藥學(xué)方面的控制應(yīng)遵循“合理可行的最低限量”原則（ALARP原則）。符合ALARP原則的雜質(zhì)水平再經(jīng)毒理學(xué)方面的進(jìn)一步評(píng)估，以驗(yàn)證其合理性（見決策樹和以下章節(jié)）。5.2.1 Pharmaceutical Assessment 藥學(xué)評(píng)價(jià)A specific discussion as part of the overall discussion on impurities (see Q3A(R) should be provid

42、ed in the application with regard to impurities with potential genotoxicity.申請(qǐng)材料應(yīng)提供關(guān)于潛在遺傳毒性雜質(zhì)的特別討論資料（見Q3A（R）。 A rationale of the proposed formulation/manufacturing strategy should be provided based on available formulation options and technologies. The applicant should highlight, within the chemical

43、 process and impurity profile of active substance, all chemical substances, used as reagents or present as intermediates, or side-products, known as genotoxic and/or carcinogenic (e.g. alkylating agents).需要根據(jù)現(xiàn)在的配方選擇和技術(shù)，提供證明所選的配方/生產(chǎn)策略合理性的證據(jù)。申請(qǐng)人應(yīng)在合成工藝和雜質(zhì)研究部分重點(diǎn)指出所有的化學(xué)物質(zhì)，包括用到的試劑、中間體、副產(chǎn)物，哪些是已知遺傳毒性和/或致癌性物

44、質(zhì)（如烷化劑）。More generally, reacting substances and substances which show “alerting structure” in terms of genotoxicity which are not shared with the active substance should be considered (see e.g. Dobo et al. 2006). Potential alternatives which do not lead to genotoxic residues in the final product, sh

45、ould be used if available.值得關(guān)注的是，雖然有些含有“可能引起遺傳毒性的結(jié)構(gòu)” （alerting structure）的反應(yīng)試劑與最終活性物質(zhì)并沒有共同結(jié)構(gòu)，但也要考慮它們的遺傳毒性(see e.g. Dobo et al. 2006).。如果有可能，應(yīng)該對(duì)它們進(jìn)行一些替代研究，以使最終產(chǎn)品中不會(huì)引入基因毒性殘留。A justification needs to be provided that no viable alternative exists, including alternative routes of synthesis or formulation

46、s, different starting materials. This might for instance include cases where the structure, which is responsible for the genotoxic and/or carcinogenic potential is equivalent to that needed in chemical synthesis (e.g. alkylation reactions).需要提供充分的論證來說明沒有可行的替代方法存在，包括可替代的合成路線或配方，不同的起始物料等。比如，應(yīng)證明具有遺傳毒性和

47、/或致癌性的結(jié)構(gòu)在化學(xué)合成中（如烷化反應(yīng)）是必需的。 If a genotoxic 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 compliance with safety needs or to a level as low as reason

48、ably practicable (see safety assessment). Data on chemical stability of reactive intermediates, reactants, and other components should be included in this assessment.如果遺傳毒性雜質(zhì)在原料中不可避免，則應(yīng)該采取適當(dāng)?shù)募夹g(shù)（如純化步驟）降低該雜質(zhì)的含量，以滿足安全性要求，或符合“合理可行的最低限量”原則（見安全評(píng)估）。藥學(xué)評(píng)估還應(yīng)包括反應(yīng)中間體、反應(yīng)物和其它組件等的化學(xué)穩(wěn)定性研究。Detection and/or quantific

49、ation of these residues should be done by state-of-the-art analytical techniques.應(yīng)該使用比較先進(jìn)的分析檢測(cè)技術(shù)來檢測(cè)和量化這些殘留的雜質(zhì)。5.2.2 Toxicological Assessment 毒理學(xué)評(píng)價(jià)The impossibility of defining a safe exposure level (zero risk concept) for genotoxic carcinogens without a threshold and the realization that complete el

50、imination of genotoxic impurities from drug substances is often unachievable, requires implementation of a concept of an acceptable risk level, i.e. an estimate of daily human exposure at and below which there is a negligible risk to human health.鑒于在沒有明確閾值的前提下定義安全暴露水平（零風(fēng)險(xiǎn)）是不可能的，且從原料藥中完全除去遺傳毒性雜質(zhì)經(jīng)常是很難

51、做到的，所以有必要提出一個(gè)“可接受風(fēng)險(xiǎn)水平”（acceptable risk level）的概念，比如估算一個(gè)“每日最大暴露量”值，低于該暴露量時(shí)就可以忽略其對(duì)人體健康的風(fēng)險(xiǎn)。Procedures for the derivation of acceptable risk levels are considered in the Appendix 3 of the Q3C Note for Guidance on Impurities: Residual Solvents for Class 1 solvents. However, these approaches require avail

52、ability of adequate data from long-term carcinogenicity studies.對(duì)于可接受風(fēng)險(xiǎn)水平的推導(dǎo)過程請(qǐng)參見Q3C（雜質(zhì)指南注釋: 一類溶液殘留）中的附件三。然而，應(yīng)用這些方法必須有足夠多的長期致癌性研究數(shù)據(jù)。In most cases of toxicological assessment of genotoxic impurities only limited data from in vitro studies with the impurity (e.g. Ames test, chromosomal aberration test

53、) are available and thus established approaches to determine acceptable intake levels cannot be applied. Calculation of “safety multiples” from in vitro data (e.g. Ames test) are considered inappropriate for justification of acceptable limits. Moreover, negative carcinogenicity and genotoxicity data

54、 with the drug substance containing the impurity at low ppm levels do not provide sufficient assurance for setting acceptable limits for the impurity due to the lack of sensitivity of this testing approach. Even potent mutagens and carcinogens are most likely to remain undetected when tested as part

55、 of the drug substance, i.e. at very low exposure levels. A pragmatic approach is therefore needed which recognises that the presence of very low levels of genotoxic impurities is not associated with an unacceptable risk.大多數(shù)情況下，遺傳毒性雜質(zhì)的毒理學(xué)評(píng)估只是局限于雜質(zhì)的體外研究（如Ames試驗(yàn)，染色體畸變?cè)囼?yàn)），但這些方法并不適用于確定雜質(zhì)可接受的攝入水平。也就是說，根據(jù)體外數(shù)據(jù)（如Ames試驗(yàn)）計(jì)算雜質(zhì)的“安全倍數(shù)（safety multiples）”、進(jìn)而確定可接受的限度，是不合適的。此外，用含有較低（ppm級(jí)）雜質(zhì)水平的原料藥研究其致癌性和遺傳毒性，即使得出陰性結(jié)果也不足以確保該雜質(zhì)限度的合理