What an IB is and why does it matter?
The IB is more than a regulatory requirement. It is a living scientific document that brings together clinical and nonclinical data to help investigators understand the investigational product, assess potential risks, and conduct the trial safely and effectively.
A well-written IB should be clear, objective, non-promotional, and aligned with related study and regulatory documents, including protocols, informed consent forms, IMPDs, DSURs, and safety updates.
Inside the guide, we cover:
- Best practices for maintaining consistency across IB versions and related regulatory documents
- How to structure an original IB in line with ICH E6(R3)
- Adapting IBs across regulatory jurisdictions
- Key considerations when writing first-in-human IBs
- How IBs evolve across early- and late-stage development
- Practical steps for planning an annual IB update
- Managing source documents, stakeholders, review cycles, QC, and publishing
- Medical writing tips for IB success
Core Structure of an IB
Developing a new IB requires more than assembling available data. Medical writers need to interpret and present information from multiple sources in a way that is scientifically accurate, balanced, and useful for investigators.
For early-stage assets, this often includes summarising pharmacology, toxicology, pharmacokinetics, formulation, handling information, and the rationale for clinical development.
Key IB components typically includes sections:
- Title page
- Table of Contents
- Summary
- Introduction
- Physical, chemical, and pharmaceutical properties
- Nonclinical studies
- Effects in humans
- Summary of data and guidance
- Reference Safety Information (RSI)
- References
Planning in Advance:
IB updates are highly collaborative and often involve input from clinical development, pharmacovigilance, regulatory affairs, nonclinical, CMC, and medical writing teams. A successful update starts with understanding what has changed since the previous version and how those changes affect the document.
The complexity of the update can vary significantly depending on the volume of new data, the maturity of the development program, the quality of the existing IB, and the expected review and approval process.
Common Challenges
Common challenges in IB development and updates include:
- Late availability of source documents
- Inconsistent information across clinical, nonclinical, safety, and regulatory documents
- Unclear ownership of review comments and decisions
- Overly lengthy IBs that lose focus for investigators
- QC and publishing requirements being considered too late in the timeline
Best Practices for Maintaining an Effective Investigator’s Brochure
A strong IB depends on more than accurate data. It also requires clear planning, cross-functional alignment, consistent document standards, and an investigator-focused approach. In the full guide, we explore five best practices for maintaining an effective IB throughout clinical development:
- Manage stakeholder input early
- Keep the IB investigator-focused
- Establish strong document standards
- Plan IB updates well in advance
- Maintain writer continuity across IB updates
Download the full guide to explore each best practice in more detail, including practical considerations for medical writers, sponsors, and cross-functional review teams.
Download the full guidePractical tip: Treat the IB as a long-term document, not a one-off deliverable. Establishing templates, style conventions, reference management processes, and QC expectations early can make future updates more efficient and reduce rework between versions.
How Morula Health Supports IB Development
Morula Health supports sponsors with the development, update, QC, and publishing of Investigator’s Brochures across clinical development. Our medical writing teams combine scientific expertise, structured project management, and established quality processes to help maintain clear, compliant, investigator-focused IBs.
Need support with an upcoming IB update? Contact our team to discuss how we can help.
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