If you are new to the regulatory guidance, even some peers in the regulated field for a while, it is still quite unclear what are the M10, S6, R2 means in ICH guidelines. So this article is only for the less experienced folks to clarify the nomenclature principles for ICH guideline names.
ICH already has a clear explanation for what are the E, Q, M, S represent. The ICH topics are divided into the four categories below and ICH topic codes are assigned according to these categories. To make it visually easy to read, please refer to the below table.
Letter | Category | explanation |
| E | Efficacy Guidelines | The work carried out by ICH under the Efficacy heading is concerned with the design, conduct, safety and reporting of clinical trials. It also covers novel types of medicines derived from biotechnological processes and the use of pharmacogenetics/genomics techniques to produce better targeted medicines. |
| M | Multidisciplinary Guidelines | Those are the cross-cutting topics which do not fit uniquely into one of the Quality, Safety and Efficacy categories. It includes the ICH medical terminology (MedDRA), the Common Technical Document (CTD) and the development of Electronic Standards for the Transfer of Regulatory Information (ESTRI). |
| Q | Quality Guidelines | Harmonisation achievements in the Quality area include pivotal milestones such as the conduct of stability studies, defining relevant thresholds for impurities testing and a more flexible approach to pharmaceutical quality based on Good Manufacturing Practice (GMP) risk management. |
| S | Safety Guidelines | ICH has produced a comprehensive set of safety Guidelines to uncover potential risks like carcinogenicity, genotoxicity and reprotoxicity. A recent breakthrough has been a non-clinical testing strategy for assessing the QT interval prolongation liability: the single most important cause of drug withdrawals in recent years. |
Now you know what the letter E, M, Q, S means, how about the numbers following the letter. The numbers are assigned to each guideline numerically from 1 to what ever numbers of topic have been regulated. Currently (as Oct. of 2022) there are numbers 1 to 20 for E, 1 to 15 for M, 1 to 14 for Q, and 1 to 12 for S have been used. If ICH make guideline for a new topic, they can continue the number. If one topic was divided into two or more sub-topic, the letter A, B, C… will be assigned after the number. If the new guideline is a revised version, it will be given a suffix like (R2), meaning Revision 2.
Take S1C(R1) for example: S means it is a guideline about the safety, 1 means this is the first topic in the safety category, which ICH provided a guideline. C means this guideline is the third sub-topic.Topic of S1 is: Carcinogenicity Studies; S1C is: Dose Selection for Carcinogenicity Studies of Pharmaceuticals.