The Investigational Medicinal Product Dossier (IMPD) is a central regulatory and study document for clinical trials involving medicinal products. It describes the investigational medicinal product (and, if applicable, comparators or placebo) in sufficient detail to enable authorities and ethics committees to assess quality, manufacturing, non-clinical data, and clinical information within the context of a specific clinical trial. In the EU, the IMPD is closely linked to the application procedure under the Clinical Trials Regulation and is usually submitted via CTIS.
Purpose: What Authorities Derive from the IMPD
The IMPD provides the technical basis for assessing the safety and scientific plausibility of a clinical trial. Authorities use it, in particular, to verify whether the quality of the investigational medicinal product is adequately controlled, whether manufacturing and testing processes are suitable, and whether non-clinical data justify the transition to clinical application. Furthermore, the IMPD serves to make the proposed dosage, administration, and risk minimization measures comprehensible in conjunction with the clinical trial protocol.
For sponsors and CROs, the IMPD also serves as a steering instrument: it consolidates CMC (Chemistry, Manufacturing and Controls) information, supply chain responsibilities, and the quality strategy. Especially for biological products, ATMPs, or complex dosage forms, the IMPD is often one of the time-critical paths in study start-up.
Typical Structure (Quality / Non-clinical / Clinical)
In terms of content, the IMPD is often divided into three main areas:
- Quality (CMC): Composition, manufacturing process, specifications, analytics, stability, packaging/labeling, GMP aspects, and release processes.
- Non-clinical: Summaries of pharmacology, pharmacokinetics, and toxicology, as well as their relevance for the planned clinical setting.
- Clinical: Overview of previous clinical data, safety and efficacy signals, and justification of the intended dose and administration schedule.
Depending on the stage of development, it may have varying levels of detail: in early phases, not all information may be fully available, but existing data must be presented coherently, and knowledge gaps made transparent. In later phases, the IMPD often becomes more extensive and standardized, especially if it is to be harmonized with an electronic Common Technical Document.
For operational implementation, it is crucial that the IMPD is “auditable”: data sources, versions, responsibilities, and approved content must be documented traceably. In practice, CMC information is often supplied by manufacturers or contract developers; the sponsor and CRO must consolidate, review, and present this content in a way that is consistent and understandable for regulatory assessment.
Distinction from Related Documents
The IMPD is often prepared together with the Investigator’s Brochure, the clinical trial protocol, and other application documents. The IB primarily addresses the information needs of investigators, while the IMPD focuses more on the regulatory assessment of quality and non-clinical/clinical data. The eCTD, on the other hand, is a format and structure standard for marketing authorization applications; IMPD content can later be incorporated into marketing authorization dossiers but is not automatically identical.
There is also a connection to documents such as the Certificate of Analysis: CoAs provide batch-specific test results and are typical appendices or references in the quality section, but they do not replace the overall presentation in the IMPD.
Regulatory Framework and GCP Reference (EU/Germany)
The legal basis for clinical trials in the EU is Regulation (EU) No. 536/2014. It defines, among other things, which documents are required for the application and how coordinated assessment between Member States takes place. In Germany, BfArM and PEI are involved as federal authorities; additionally, the approval of the responsible ethics committee is required. For sponsor teams, this means: IMPD content must not only be scientifically correct but also consistent, auditable, and available in the correct version within the application package.
From a GCP perspective, the IMPD is part of the quality and documentation landscape that ensures investigational medicinal products are appropriately manufactured, tested, stored, and used. ICH E6(R3) emphasizes risk-based quality management; this translates into practical requirements for change control, supplier management, and the traceability of critical quality decisions, which should be reflected in the IMPD.
Updates, Change Management, and Common Pitfalls
IMPDs are updated during the course of a study if manufacturing processes, specifications, stability data, or clinical findings change. Changes that could affect product quality or the risk profile are particularly critical. In such cases, the sponsor and CRO must assess whether a substantial modification exists and how it should be submitted within the regulatory processes.
Typical problems include inconsistent information between the IMPD, IB, and clinical trial protocol, unclear responsibilities in the supply chain, missing stability data for the planned duration, or inadequately justified specifications. Best practices include early CMC alignment, clearly defined data sources, a rigorously maintained change control system, and review by quality assurance and regulatory affairs.
FAQ
When is an IMPD required?
An IMPD is generally required in the EU for clinical trials involving investigational medicinal products that are applied for via the European procedure under Regulation (EU) No. 536/2014. Exceptions may be possible for authorized medicinal products or certain risk constellations, but these are case-dependent.
What role does GMP play in the IMPD?
The quality section describes manufacturing and testing steps, specifications, and release processes. GMP aspects essential for product safety and quality must be addressed comprehensibly, without unnecessarily disclosing confidential details.
Which regulatory references are particularly relevant for the IMPD?
For the EU, Regulation (EU) No. 536/2014 as the legal framework for clinical trials and ICH E6(R3) Good Clinical Practice as a GCP reference are particularly important. Additionally, ICH E8(R1) can be consulted as context for modern study planning.