Clinical module authoring plays a critical role in determining the success of a medicinal product’s approval in Regulatory submissions. Regulatory authorities worldwide rely heavily on the accuracy, structure, and clarity of Modules 2.5, 2.7, and 5 of the Common Technical Document (CTD). However, even experienced Regulatory teams can fall into common traps that delay approvals, trigger questions, or lead to rejection.

In this blog, we’ll explore the top five mistakes in CTD clinical module authoring and, more importantly, how your team can avoid them.

1. Inconsistent Cross-Referencing Between Clinical Modules

The Problem

Modules 2.5 (Clinical Overview) and 2.7 (Clinical Summaries) are meant to summarize the full clinical study reports (Module 5). However, discrepancies often arise—whether in study numbers, table labels, or interpretation of results. These inconsistencies can erode reviewer confidence and invite unnecessary queries.

The Solution

• Establish a master cross-reference tracker to maintain alignment across modules.
• Use version control systems for Regulatory writing to ensure all references point to the most up-to-date documents.
• Schedule a final consistency checks for CTD submission before compiling the eCTD package.

2. Missing or Broken Hyperlinks in eCTD Submissions

The Problem

Hyperlinks in eCTD clinical modules are essential, allowing regulators to navigate between documents efficiently. Broken links or incorrect document references can significantly delay the Regulatory review process and reflect poorly on the quality of the submission.

The Solution

• Implement a hyperlink validation checklist as part of your QA process.
• Avoid last-minute file renaming, which can break previously inserted links.
• Use document management systems for Regulatory submissions that support automatic hyperlinking for recurring templates and structures.

3. Incomplete Study Synopses in Module 5

The Problem

Each clinical study report in Module 5 should contain a synopsis that captures the study design, objectives, primary/secondary endpoints, safety results, and conclusions. Omissions or vague summaries can raise Regulatory concerns about transparency or data quality.

The Solution

• Use a standardized study synopsis template for Module 5 that covers all critical components.
• Conduct internal peer reviews of clinical documents to check for completeness and clarity.
• Include tabulated data and visual summaries of clinical trial results to enhance understanding.

4. Poorly Structured Clinical Overviews in Module 2.5

The Problem

The Clinical Overview is more than a summary—it’s a strategic narrative. Poorly structured overviews that merely repeat data from Module 2.7 without interpretation or context can miss the opportunity to shape the regulator’s perspective on the product’s benefit-risk profile.

The Solution

• Structure the overview with clear sections: clinical development rationale, efficacy summary, safety profile, and benefit-risk assessment.
• Use data-driven storytelling in Regulatory writing to highlight how each study supports product claims.
• Conclude with a strong, justified recommendation on the intended therapeutic indication.

5. Ignoring Region-Specific CTD Requirements

The Problem

Although the CTD format is internationally harmonized, different Regulatory agencies have region-specific expectations. For instance, EMA may require additional appendices, while the US FDA may prefer certain statistical presentations or data formats.

The Solution

• Maintain an up-to-date checklist for regional CTD submission requirements.
• Assign regional reviewers for clinical submissions to validate the content against local expectations.
• Customize the submission package while retaining core consistency in clinical interpretation.

Bonus Tip: Focus on the Regulatory Reviewer’s Experience

A well-authored clinical module isn’t just accurate—it’s easy to navigate. Use clear headings, consistent formatting, and Regulatory writing best practices to help regulators absorb your message efficiently. The easier you make their job, the smoother your Regulatory approval process will be.

Final Thoughts

Clinical module authoring in Regulatory medical writing demands precision, clarity, and strategic insight. By proactively addressing the mistakes outlined above, you not only reduce the risk of delays but also present your product with the professionalism it deserves.

At Freyr, we specialize in Regulatory medical writing services, including CTD module authoring, clinical data summarization, and global dossier preparation. Our team ensures your submissions are compliant, compelling, and customized to each market’s expectations. Reach out to us today for expert support in authoring, reviewing, or optimizing your clinical modules.