Revision of the ICH Guideline Q3C: New toxicological Data for Methyl Isobutyl Ketone and Triethylamine
ICH指南Q3C修订：甲基异丁酮和三乙胺新的毒性数据
The ICH guideline Q3C "Impurities: Guideline for residual solvents" contains specifications for several organic solvents that are used in the synthesis of active pharmaceutical ingredients, intermediate products or raw materials. Due to their, in some cases, high toxic potential, appropriate limit values in the final products must be checked and observed, specifying the remaining solvent content.
新的ICH指南Q3C“杂质：残留溶剂指南”中包括了几个用于原料药、中间体或原料合成的新的有机溶剂的质量标准。鉴于其在某些情况下较高的潜在毒性，在制剂成品中残留的溶剂含量必须进行检查，并定义适当的限度值。
ICH Q3C divides solvents into 4 classes:
ICH Q3C将溶剂分为四类：
Class 1: Solvents to be avoided. These substances are highly toxic, in some cases genotoxic or harmful to the environment and should not be used. If their use is unavoidable, the stated limit values must be observed.
第一类：要避免使用的溶剂。这些物质具有高毒性，在有些情形下具有基因毒性或对环境有害，不应该使用。如果不避免使用，则必须查出其所声明的限度值。
Class 2: Solvents to be limited. These solvents are toxic in certain concentrations but can be tolerated below their maximum permitted daily doses (PDE values).
第二类：限制使用溶剂。这些溶剂在特定的浓度下有毒，但低于最大允许日摄入量（PDE值）时可以允许。
Class 3: Solvents with low toxic potential. The intake of these solvents is uncritical in quantities of up to 50 mg per day without any significant health risk. However there are no long-term toxicology studies for most of these solvents.
第三类：低毒性溶剂。每天摄入这些溶剂达50mg时不会对健康有明显的风险。但是，大多数三类溶剂还没有长期毒性研究数据。
Class 4: Solvents for which no adequate toxicological data was found. According to ICH Q3C manufacturers of active ingredients and excipients still must give a reason for the remaining content of these substances in the final product (important for the authorisation dossier).
第四类：还没有发现足够的毒性数据的溶剂。根据 ICH Q3C，原料药和辅料生产商还是必须给出制剂中这些物质残留量的理由（对于上市许可注册文件来说非常重要）。
In the course of scientific advances, this guideline was revised on several occasions due to the reclassification of solvents or a change in their PDE values as a result of new toxicological data. The currently valid ICH Q3C version is the ICH Q3C(R5).
由于科学研究的进展，本指南对溶剂进行了重新分类，或根据新的毒性数据对其PDE值进行变更，从而进行了几次修订。现行有效版本是ICH Q3C（R5）。
In June this year the ICH published a further revision as a "Draft Consensus Guideline" ICH Q3C(R6)" (Step 2 document). The document contains the following changes:
本年6月，ICH公布了修订版本为“一致同意的指南草案ICH Q3C(R6)”（第2阶段文件）。文件包括以下变更：
Reassessment of methyl isobutyl ketone (MIBK): In more recent studies, a higher toxic potential was determined compared to the data from older studies. As a result, MIBK was reclassified from class 3 to class 2.
甲基异丁酮（MIBK）的重新评估：在最近的研究中，相比于之前的研究，认为其具有更高的毒性。因此，MIBK被从原来的第三类重新分类为第二类。
Addition of triethylamine to the guideline: This solvent is frequently used due to its favourable solubility properties, which allows it to catalyse certain chemical reactions. Based on the latest toxicological data, it is classified under class 3.
增加三乙胺：由于其较好的溶解性质，使用较为频繁，它可以催化某些化学反应。根据最近的毒性数据，它被划分为第三类。
ICH Q3C(R6) was released for comment on 4 August 2015 on the "Scientific Guidelines" site of the EMA as a Step 2b document (end of consultation period: 3. November 2015).
ICH Q3C(R6)于2015年8月4日在EMA的“科学指南”栏目中作为第2b阶段文件公开征求意见（征求意见截止2015年11月3日）。