1、 国家食品药品监督管理局培训中心高级培训班 - “美国仿制药申报最新要求和案例分析”FDA对药物杂质的控制要求：Contents 目录原料药与成品药中的有机杂质有机杂质来源和控制有机杂质控制限度的论证案例分析：杂质控制限度的设置和论证练习-杂质控制限度的设置和论证原料药与成品药中的残留溶剂残留溶剂的指导原则和控制限额的建立案例分析：如何建立残留溶剂控制限额具有基因毒性杂质的控制练习-残留溶剂控制限额的建立和论证Drug Production and Quality Control Synthesis of APIFDA对药物杂质的控制要求 原料药与成品药中的有机杂质p 1999年11月，FDA
2、-“仿制药申请的原料药杂质研究指导原则”，“仿制药申请的制剂杂质研究指导原则”。p 2003年，ICH修订的Q3A(R)“新原料药杂质研究指导原则”，“新制剂的杂质研究指导原则”（简称Q3B(R)。p 杂质分类有机杂质 合成杂质合成杂质(Synthetic Impurity)或工艺杂质或工艺杂质(Process Impurity)：一般来自生产过程中残留的原料、中间体、试剂、配体和催化剂以及反应副产物。只与原料药的生产过程有关，在原料药和制剂的储存中一般不可能增长。通过对合成路线的分析可以确定某一杂质是否为合成杂质。 降解产物降解产物(Degradation Product):来源于原料药通过
3、各种不同的化学反应途径的降解，一般需要结合对合成路线的分析和试验研究的结果，以确定某一杂质是否为降解产物。 有的有机杂质既是合成杂质，又是降解产物。有的有机杂质既是合成杂质，又是降解产物。无机杂质：来自生产过程所用的试剂（如氯化物）、配体和催化剂（如钯，铂等），包括重金属或其它金属残留，以及无机盐（例如，助滤剂、活性炭等）。它们通常是已知和确定的。残留溶剂：生产过程中使用后未完全除去的溶剂（如甲醇、甲苯、四氢呋喃等），残留的可挥发性试剂（如三乙胺等）和反应中生成的可挥发产物。有机杂质来源常见的降解反应常见的降解反应确定降解产物-强制降解研究（Forced Degradation Study)S
4、tress Type强制降解类型Common Stress 常用强制降解Common Forced Degradation Conditions 常见强制降解条件Solution Stress溶液降解Acid 酸0.1N HCl , 室温-100，4小时Base 碱0.1N NaOH，室温-100，4小时H2O2 双氧水1-3% H2O2， 室温，4小时Heat 加热H2O， 100，4小时UV & Visuable Light 紫外光和可见光（300-800nm）15小时（相当于波长范围为300-800nm,约2.0百万勒克斯时Stress固态降解Thermal 加热 60 ，14天Heat
5、/humidity 加热/湿度40 /75%RH，14天UV & Visuable Light 紫外光和可见光（300-800nm）15小时（相当于波长范围为300-800nm,约2.0百万勒克斯时p强制降解试验：强制降解试验：将原料药或制剂置于比通常储存条件剧烈得多的试验条件下进行稳定性考察的一系列试验。p目的：目的：了解该药品的稳定性及其降解途径与降解产物。在一定程度上对有关物质分析方法的专属性进行验证。p实际操作：实际操作：试剂的浓度、反应的温度和时间等都应根据具体情况作调整。p强制降解程度：强制降解程度：根据经验一般认为，控制适当的强制降解条件，从而达到大约10%的原料药降解是比较合适
6、的。p常见的强制降解具体试验项目与试验条件常见的强制降解具体试验项目与试验条件确定降解产物-原料药和制剂的稳定性试验长期（25 2 、相对湿度60% 5%、至少12个月）稳定性试验加速（ 40 2 、相对湿度75% 5%、至少6个月）稳定性试验分析研究收集到的稳定性测试数据（Stability Data）也是确定降解产物的重要依据之一。一般测定不同时间样品的HPLC图谱并进行比较分析，并与长期保留制剂样品的测定结果进行比较。在强制降解试验研究过程中注意观察样品外观性状、原料药含量等变化，并与杂质检查结果相互印证。原料药和杂质的分离和检测：将可能的中间体和副产物作为杂质进行柱效、流动相及流动相比
7、例、波长和分离度等方法学的研究。待方法建立成熟后，根据中间体和副产物的安全性和获得杂质标样的难易程度，决定是否定为已知杂质。如果杂质标样难以得到，且比较安全，可考虑采用杂质校正因子加上相对保留时间的方法，或采用杂质相对保留时间加上自身对照的方法，对该杂质进行定量分析。如果得不到该杂质样品作为标样，对于有紫外吸收的样品可以用二极管阵列检测器，考察未精制的粗品，并对比已精制过的样品，确定粗品种各成分的分离度和样品中可能杂质的检测波长。方法确立后，可采用自身对照方法或面积归一化法控制杂质。原料药与成品药中的有机杂质p药品中有机杂质的分类有机杂质特定杂质（Specified Impurities)：特
8、定杂质是指在质量标准中分别规定了明确的限度，并单独进行控制的杂质。特定杂质包括化学结构已知的杂质（Specified Identified Impurity) 和化学结构未知（Specified Unidentified Impurity）的杂质。美国药典通常采用代号来指认特定杂质，如相关化合物A（Related Compound A）等。非特定杂质（ Unspecified Impurities ）：在标准中未单独列出，而仅采用一个通用的限度进行控制的一系列杂质。其结构未知，在药品中出现的种类与几率并不固定。一般采用合适的定性分析指标加以指认，如相对保留时间为3.5的杂质。有机杂质检测确定原
9、料药和制剂中潜在的合成杂质和降解产物，需要应用专业的有机化学知识对有关合成化学反应和条件、原料药化学结构、理化性质、稳定性等进行全面的科学分析和论证，并且比较实验室对样品的常规分析和强制降解（Forced Degradation Study），以及稳定性研究的结果。Impurities: Origination & Identification Classification of impuritiesSynthetic Impurities (Residual substances in the synthesis) Starting material By-products Intermed
10、iates Degradation during synthesis Reagents, ligands and catalystsDegradation ProductsHydrolysisOxidationEsterificationElimination of water, HCl, etc.DehydrogenationResidual Solvents/OVIs Solvents/reagents used in the reactions, purification process or formed during reactionMeOH, EtOH, IPA, THF, Dic
11、hloromethane, Acetone, Triethylamine, etc.Impurity Resources-API & Drug Product Manufacturing ProcessesImpurities: Origination & Identification Lists of Impurities in ICHOrganic impuritiesEach identified specified impurityEach unidentified specified impurityAny unspecified impurity with an acceptanc
12、e criterion of not more than () the figure in the identification threshold in Attachment 1, ICH Q3A(R)Total impuritiesResidual solventsInorganic impurities有机杂质控制限度设置有机杂质控制限度设置美国药典杂质：美国药典杂质：在美国药典正文（monograph）中列为特定杂质（Specified Impurities）的杂质，其控制限度应设置不高于美国药典的限度。非美国药典杂质：非美国药典杂质：如果美国药典正文没有对该杂质设置控制限度，或者美国
13、药典没有改药物的正文，则根据ICH的杂质指导原则Q3A(R)和Q3B(R)，同时也参考其它药典，如欧洲药典（EP）和英国药典（BP）来设置该杂质的控制限度。就ICH的杂质指导原则来说，如果该杂质在实验测试中的实际观测水平高于ICH的鉴定限，则必须确定为特定杂质，其控制限度必须设置为不高于ICH的论证限（Qualification Threshold）。非特定杂质：非特定杂质：在药品中出现的种类与几率并不固定。因此，在药品的临床前与临床研究中，很难对这些杂质的安全性进行评估。为将这些杂质可能带来的安全性隐患降至最小，ICH的杂质指导原则Q3A(R)和Q3B(R)对其限度用鉴定限（Identifi
14、cation Threshold）做了明确的规定，要求在原料药标准中任何单个非特定杂质的限度不得超过鉴定限。在仿制药或改剂型药品以及药品上市后变更原料药生产商等研究中，即使出现了新的杂质，只要新杂质的含量低于表中的鉴定限，就可以认定这些新杂质的安全性。有机杂质控制限度设置有机杂质控制限度设置Find out the Maximum Daily Dose (MMD,每日最大剂量) from PDR, CPS, etc.Use MDD to calculate the ICH ThresholdsReporting Threshold (RT)Identification Threshold (I
15、T)Qualification Threshold (QT)每日最大剂量1报告限(Reporting Threshold) 2,3鉴定限（Identification Threshold) 3论证限(Qualification Threshold) 3 2 g/day0.05%每日摄入量0.10%或1.0毫克（取低值）每日摄入量0.15%或1.0毫克（取低值） 2 g/day0.03%0.05%0.05%1 每日原料药的服用量。每日原料药的服用量。2 更高的报告限必须提供充足的理由。更高的报告限必须提供充足的理由。3 如果杂质的毒性特别高则适合于更低的报告限。如果杂质的毒性特别高则适合于更低的
16、报告限。Control of Impurities: Compendia & ICH Establishing Acceptance Criteria for ImpuritiesAcceptance criteria (limits) for impurities should be set no higher than the level that has been qualified.In establishing impurity limits, the first critical consideration is whether an impurity is specified i
17、n the USP.If there is a monograph in the USP that includes a limit for an identified specified impurity, the limits should be set no higher than the official compendial limit.If qualified by an FDA-approved human drug product, the limits must be consistent with the level observed in the approved hum
18、an drug product.In other circumstances (e.g. metabolites), the limits may need to be set tighter than the qualified level to assure drug substance quality. If the level of the impurity is above the level specified in the USP, qualification is necessary. Then, if appropriate qualification has been ac
19、hieved, an applicant may wish to petition the USP for revision of the impuritys limits.Control of Impurities: Compendia & ICH ICH Q3A(R) and Q3B(R). ScopeDoes not apply to new drug substances (Q3A(R) ) or products (Q3B(R) used during the clinical research stages of development. Both do not cover: Bi
20、ological/ biotechniological products Fermentation products Peptides Semi-synthetic products Oligonucleotides Herbal products Radiopharmaceuticals Crude products of animal Plant originQ3B (R) does not cover:lExtraneous contaminants that should not occur in new drug products and are addressed as GMP i
21、ssues.lPolymorphic formslEnantiomeric impurities制剂的杂质限度制剂的杂质限度Q3B(R2). ICH Threshold for Degradation Products in New Drug Products每日原料药最大剂量 *报告限（Reporting Threshold)鉴定限（Identification Threshold)论证限(Qualification Threshold) 1g0.1%N/AN/A 1g0.05%N/AN/A 10mg 2gN/A0.2% or 2mg TDIN/A 100mg 2gN/AN/A0.2% or
22、 3mg TDI 2gN/A0.10%0.15%*取低值，按百分含量或每日总摄入量（TDI）计。有机杂质控制限度论证有机杂质控制限度论证杂质控制限度论证：对一定限度的杂质的生物安全性进行研究和评估，建立杂质的可接受限度并提供包括安全性考虑在内的依据。如果杂质在样品测试中的实际观察值较高，而需要设置一个高于美国药典或ICH论证限（ Qualification Threshold ）的控制限度时，则必须提供一个充分合理的论证来说明所设的控制限度是合理的。有时将杂质水平降低至美国药典或ICH论证限以下是最为简单的杂质控制方法。对杂质控制限度的论证如果被FDA接受，申请人还可以向美国药典提出修改该杂质
23、限度的申请（Petition）。 制订和论证杂质合理限度的决策树有机杂质控制限度的论证方法有机杂质控制限度的论证方法对比分析法：对比分析法：仿制药申请中原料药的杂质可以采用相同的已验证的分析方法（如HPLC法），与FDA已批准的同品种人用制剂（Reference Listed Drug, 简称RLD，参照药品）进行对比研究。如果无法获得参照药品，也可对含有相同原料药，以及相同给药途径和特征的不同药物制剂（如片剂对胶囊）的杂质含量进行研究。如果仿制药申请原料药中已鉴别杂质的水平与相应已获准上市人用药物的杂质水平相当，则可以认为该杂质得到了合理控制。科学文献和主要代谢物法：科学文献和主要代谢物法：
24、如果科学文献已经证明某一水平的杂质在安全性方面没有问题，那么根据这一水平建立的该杂质的限度就无需进一步论证。此外，如果科学文献证明某杂质本身也是原料药在体内代谢的主要代谢物，其安全性是显而易见的，因而即使对该杂质设置高于ICH论证限的控制限度，通常可以也认为该杂质已得到合理控制。遗传毒性研究法：遗传毒性研究法：由于遗传毒性试验费时间且成本高昂，此法一般是在前两种都无法对杂质合理研究论证的情况下才采取的方法。这项研究可以采用含该杂质的制剂或原料药直接进行研究，但实际上采用已分离的杂质进行研究可能更为恰当。有机杂质控制限度的论证方法有机杂质控制限度的论证方法杂质的合理控制应基于多种因素，包括患者人
25、群、日剂量、给药途径以及给药周期。杂质合理控制的最基本原则就是考虑其安全因素。根据ICH的杂质指导原则Q3A(R)和Q3B(R)。 当满足下述一个或多个条件时，可以认为该杂质的控制限度是合理的：当杂质实际观察水平以及控制限度未超出FDA已经批准的人用制剂杂质实际观察水平； 当杂质本身是原料药在动物和/或人体内重要的代谢产物时；当杂质实际观察水平以及控制限度有充分合理的科学文献支持时；当杂质实际观察水平以及控制限度未超过通过体外遗传毒性比较研究得出的正确评估限度时。有机杂质控制限度的论证方法有机杂质控制限度的论证方法当杂质本身是原料药在动物和当杂质本身是原料药在动物和/或人体内重要的代谢产物时或
26、人体内重要的代谢产物时如果有可靠文献报道该杂质系人体代谢产物，其限度的确定并不需要从安全性方面进行论证。限度设定时主要考虑批分析数据、稳定性研究数据。具体限度的确定因药物而异，但应能保证批间药品质量的一致性，且得到批分析数据、稳定性数据的支持。Example:Simvastatin EP Imp A, Degradation Product: Proposed to increase the limit from 0.5% to 1.0%.Rationale: The FDA guideline for ANDAs: Significant metabolites do not need fu
27、rther qualification. The metabolic profiles of Simvastatin in human and dog plasma showed that Simvastatin EP Imp A is one of the major metabolites.Impurity Limit Establishment: Examples Simvastatin Tablets USP. Limits for SV RCA and SV RCBSimvastatin (Zocor): A lipid-lowering drug approved by FDA i
28、n Dec.1991. It reduces cholesterol by inhibiting an enzyme in the liver (HMG-CoA reductase) required for the production of cholesterol. Other statins include Lovastatin (Mevacor), atorvastatin (Lipitor), fluvastatin (Lescol), and rosuvastatin (Crestor).SV RC A and SV RC B were controlled at NMT0.5%
29、and 0.1%, respectively before. However, the results form the long term stability test exceeded the limits.SV RC B, Degradation Product: Proposed to increase the limit from 0.1% to 0.2%.Rationale:The ICH guideline Q3B(R): QT for degradation products can be 0.5% or 200mg TDI, whichever is lower, for t
30、he drug with MDD of 10-100mg.MDD for Simvastatin is 80mg. QT can be 0.25%. Impurity Limit Establishment: ExamplesBupropion ER Tablets: Justification for Increasing LimitsThe limit for RC m-chlorobenzoic acid in Bupropion Hydrochloride ER Tablets is proposed to increase from 0.3% to 0.5%.Rationale:Bu
31、propion is extensively metabolized in humans, rats and dogs. Metabolism studies in human indicated that bupropion was metabolized to m-chlorohippuric acid, erythro-amino alcohol (EB), threo-amino alcohol (TB), hydroxy metabolite (HB) (references 1-3).It was obvious that m-chlorohippuric acid, which
32、is excreted as the major urinary metabolite, was resulted from oxidation of the bupropion side chain to give m-chlorobenzoic acid followed by conjugation with glycine. Other aminoalcohol metabolites such as EB, TB and HB are formed from hydroxylation nof the tert-butyl group of bupropion and /or red
33、uction of the intact parent aminoketone. This metabolism pathway has been confirmed by the fact that the metabolism in rats and dogs gave predominantly m-chlorohippuric acid and m-chlorobenzoic acid as the metabolites, which are formed from side chain oxidative cleavage.The FDA guideline for impurit
34、ies for ANDAs (See Guidance for Industry. ANDAs: Impurities in Drug Substances) indicates that the impurities that are significant metabolites do not need further qualification.It is considered reasonable to increase the test limit from 0.3% to 0.5% for BP RC2 (m-chlorobenzoic acid ).Impurity Limit
35、Establishment: ExamplesSynthetic Impurities: No Need to Monitor/Report in DP SpecificationsResponse form FDA on this type of question: Synthetic impurities need not be reported or monitored for release and /or stability testing of the drug product. Thus, no drug product limits for drug substance pro
36、cess impurities need be included in the drug testing protocol.Rationale:Synthetic impurities are generated during the manufacturing process of the drug substance.They are controlled in the drug substance specification.They are not expected to increase during the production and storage of the drug pr
37、oduct.Impurity Limit Establishment: Examples Semi-Synthetic or Synthetic Chemical?“Why is the FDA asking us to qualify an impurity observed in this semi-synthetic drug substance? Arent semi-synthetics excluded from the recommendations?”Rationale: It depends on how far the drug substance is from the
38、naturally derived source material. In general, drug substances separated from the source material by one or two chemical manipulations are still excluded from the recommendations. However, the Agency believes that those drug substances separated from the source material by several synthetic steps re
39、sulting in multiple isolated and purified intermediates resemble traditional chemicals more than they resemble classical semi-synthetic moieties. Hence, the new recommendations would apply to such drug substances. Impurity Limit Establishment: Examples Clyndamycin. Semi-synthetic or Synthetic Chemic
40、al?案例分析：有机杂质控制限度设置和论证案例分析：有机杂质控制限度设置和论证 卡托普利（卡托普利（Captopril) 原料药的合成路线原料药的合成路线卡托普利（卡托普利（Captopril）有机杂质控制限度的设置）有机杂质控制限度的设置卡托普利（卡托普利（Captopril）有机杂质控制限度的）有机杂质控制限度的设置设置l美国药典和欧洲药典都发表了有关卡托普利原料药的正文。根据美国药典正文，Captopril disulphide 杂质控制限度不超过1.0%，而其它单一杂质不超过0.2%，总杂质不超过0.5%。欧洲药典正文把杂质A,B,C,D,E和F作为特定杂质控制在不超过0.15%（其中
41、例外的是杂质A控制在1.0%，杂质F控制在0.2%），非特定杂质控制在不超过0.10%，总杂质不超过1.2%。l如果原料药生命符合美国或欧洲药典标准，通常必须符合该药典正文的每一项要求。然而，对于与合成路线毫无关系的药典杂质，在实验测试结果显示“None Detected未检出”的基础上，可以从合成路线和化学反应机理的角度进行论证，提供足够理由说明在原料药标准中可以不设限度进行常规控制。l下面以声明符合美国药典标准的卡托普利为例来说明如何提供适当的理由对所指定的标准进行论证。从化学反应机理的角度考虑，杂质B和D产生于含溴的原料，与康乐化学公司的合成路线无关。标准规格中勿需设定限度来控制杂质B和
42、D。l卡托普利的最高剂量为450毫克/日。根据ICH指导文件Q3A(R)，原料药的报告限（Reporting Threshold)为0.05%，鉴定限（Identification Threshold）为0.10%，论证限(Qualification Threshold) 为0.15%。l原料药中的控制限度设置如下：已知杂质C和E中单一已知杂质不超过0.1%，杂质A不超过0.5%，杂质F不超过0.2%，单一未知杂质不超过0.10%，总杂质不超过0.5%。此杂质控制限度符合或紧于美国药典要求，也与ICH和原料药厂家的要求一致。练习练习-杂质控制限度的设置和论证杂质控制限度的设置和论证Michel
43、le is working in a generic pharmaceutical company to develop a drug product called OME for ulcer disease. She adopts the European Pharmacopoeia HPLC method to analyze the drug substance and observed known EP impurities A (0.25), B(0.46%) and C (0.20%), and an unknown impurity 1 (0.18%). The maximum
44、daily dose for OME is 120mg. It is reported that impurity B is a degradation product and metabolite, impurities A is also a degradation product, while impurity C is a synthetic impurity. Table 1. ICH Thresholds for Impurities in New Drug SubstancesMaximum Daily Dose-1Reporting Threshold2,3Identifica
45、tion Threshold 3Qualification Threshold 32g/day0.05%0.10% or 1.0mg per day intake (whichever is lower)0.15% or 1.0mg per day intake (whichever is lower)2g/day0.03%0.05%0.05%1 The amount of drug substance administered per day.2 Higher reporting thresholds should be significantly justified.3 Lower thr
46、esholds can be appropriate if the impurity is unusually toxic.练习练习-杂质控制限度的设置和论证杂质控制限度的设置和论证Active ingredient maximum daily doseReporting ThresholdsIdentification Threshold*Qualification Threshold* 1g0.1%N/AN/A 1g0.05%N/AN/A 10mg 2gN/A0.2% or 2mg TDIN/A 100mg 2gN/AN/A0.2% or 3mg TDI 2gN/A0.10%0.15%Ta
47、ble 2. ICH Thresholds for Degradation Products in New Drug Products* Take the lower figure, % or total daily intake (TDI)练习练习-杂质控制限度的设置和论证杂质控制限度的设置和论证lUse the above Tables 1 and 2 as references and other knowledge you learned from this course to establish appropriate controlling limits and fill into
48、 Table 3 for Impurities A, B and C for both drug substance and drug product if necessary.lIt is not required to establish a limit to control impurity C for drug product. However, the HPLC method for degradation products should be capable of detecting and separating impurity C from other impurities.
49、Why?lWhy can a limit for a degradation product be considered qualified even it exceeds the ICH limit?Reporting Threshold (%)Impurity A (%)Impurity B (%)Impurity C (%)Unknown Impurity 1 (%)ICH limits for Drug substanceRecommended Limits for Drug SubstanceICH limits for Drug ProductRecommended Limits
50、for Drug ProductFDA对药物杂质的控制要求对药物杂质的控制要求 原料药与成品药中的残留溶剂原料药与成品药中的残留溶剂1997年，ICH制订了“Q3C杂质：残留溶剂的指导原则”。美国药典（USP）2008年修正了第节，重新命名为残留溶剂（Residual solvents）。ICH将药品生产及纯化过程中常用的69种有机溶剂按照对人体和环境的危害程度分为4类。第1类溶剂：指已知或极可能对人体致癌和对环境有害的溶剂，在药品制造过程中必须避免使用。其残留量必须严格控制在规定的范围内。第2类溶剂：指无基因毒性但有动物致癌性的溶剂，可以选择适当的方法并建立一定的限度进行控制。第3类溶剂：指
