What is the Common Technical Document (CTD), and what goes in each module?

1What the CTD is.

ICH M4 sets out “the agreed upon common format for the preparation of a well-structured Common Technical Document for applications that will be submitted to regulatory authorities”. Before it, each region organised registration dossiers its own way: Japan required the GAIYO, Europe required Expert Reports and tabulated summaries, and FDA had its own guidance on the format of an NDA.¹

M4 reached Step 4 on 8 November 2000. The current version, M4(R4) of 15 June 2016, revised its granularity annex to add tables for eCTD v4. It is recommended for adoption by the regulators of the EU, Japan, the US, Canada and Switzerland.¹ FDA publishes it as guidance for industry, with a scope covering new pharmaceuticals “including biotechnology-derived and biological products”.²

The CTD organises information; it does not decide what information is needed. In ICH’s words, it “is not intended to indicate what studies are required”. Applicants should not change its overall organisation, though they may adapt individual formats in the nonclinical and clinical summaries.¹ Three companion guidelines set the detail: M4Q for quality, M4S for nonclinical safety and M4E for clinical efficacy and safety.¹

2The five modules.

Module 1 is region specific, and Modules 2 to 5 “are intended to be common for all regions”. ICH’s diagram of the dossier marks Module 1 as not part of the CTD itself.¹ Module 4’s study reports run from primary and secondary pharmacodynamics and safety pharmacology, through absorption, distribution, metabolism and excretion, to single-dose and repeat-dose toxicity, genotoxicity, carcinogenicity, reproductive and developmental toxicity and local tolerance.³ Module 5’s reports are grouped as biopharmaceutic studies, studies using human biomaterials, human pharmacokinetic and pharmacodynamic studies, efficacy and safety studies, post-marketing experience, and case report forms and individual patient listings.⁴

3What goes in Module 3.

Module 3’s Body of Data is split into the drug substance (3.2.S) and the drug product (3.2.P).⁵

Appendices in 3.2.A cover facilities and equipment, adventitious agents safety evaluation, and excipients. Section 3.2.R holds regional information, such as executed batch records and the method validation package for the US, or the process validation scheme for the drug product in the EU. M4Q says the Body of Data “merely indicates where the information should be located”: the type and extent of data are set elsewhere and may depend on regional guidance.⁵

4How the Module 2 summaries work.

Module 2 opens with an introduction of the pharmaceutical’s class, mode of action and proposed clinical use, generally no longer than a page.¹ The Quality Overall Summary “follows the scope and the outline of the Body of Data in Module 3”, and should not include information, data or justification that Module 3 or another part of the CTD does not already contain. It normally runs to no more than 40 pages of text, or 80 for biotechnology products and other complex processes, excluding tables and figures.⁵ Its sections mirror Module 3: 2.3.P.8, for example, includes a tabulated summary of the stability results in 3.2.P.8.3.⁵

5How the CTD relates to the eCTD.

The CTD is the organisation of the dossier; the eCTD is the electronic format in which it is sent. FDA calls the eCTD “the standard format for submitting applications, amendments, supplements, and reports” to CDER and CBER, and requires it for NDAs, ANDAs, BLAs, commercial INDs and master files such as DMFs, with all their later submissions. It is optional for noncommercial INDs, blood and blood components, and Type III master files.⁶

FDA publishes submission standards for eCTD v3.2.2 and v4.0. From 16 October 2026, CDER and CBER support forward compatibility, so an application first submitted in v3.2.2 can continue in v4.0. FDA has said it will give advance notice before it accepts v4.0 only.⁶ For Modules 2.3 and 3, ICH’s granularity annex sets which documents go where according to the eCTD version, and asks applicants to keep the same approach for the life of the dossier, since changed information is sent as replacement documents.¹

6What is changing.

ICH M4Q(R2) is a major revision of the quality guideline, intended to improve registration and lifecycle management, support digitalisation, and fit recent ICH guidelines and complex or novel products. It is a Step 2b draft: the EU consultation ran from 25 June to 24 October 2025, and EMA published the overview of comments on 20 February 2026.⁷ FDA issued it as draft guidance, not for implementation, in January 2026.⁸ ICH’s work plan of 10 July 2026 expects the comments to be resolved by November 2026 and the final guideline to be adopted at Step 4 in June 2027.⁹ Until it is finalised, the adopted quality guideline remains M4Q(R1), whose Step 4 version is dated 12 September 2002.⁵⁷

7How it runs in Seal.

Seal works inside the CTD’s structure. In the regulatory submissions workflow, each section keeps the studies, batches and results it rests on, and new source data creates review work instead of silently changing approved text. Neil, Seal’s AI agent, can draft a section such as the 2.3.P.8 stability summary with each value cited and flag claims the evidence does not support; authors and reviewers decide what it says, and dossier assembly, validation and transmission stay with your publishing tools.

For CMC, each Module 3 section is prepared from the versioned records it describes: 3.2.S.2 and 3.2.P.3 from process definitions and runs, 3.2.S.4 and 3.2.P.5 from specifications and method versions, and 3.2.S.7 and 3.2.P.8 from stability protocols, data cuts and results. The laboratory, the submission and each market’s approval can hold different versions, and Seal keeps them distinct, with regulatory information management holding each market’s approved state.