Regulatory Submission: A Stats Perspective
The Common Technical Document (CTD) serves as a standardized format for submitting new drug applications globally, developed by the International Conference on Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) in 2002. This document facilitates the integration of quality, safety, and efficacy data, which regulatory agencies across all ICH regions accept. Structured like a triangle, the CTD segregates its content into various modules, with detailed data placed in lower modules and increasingly summarized data as one ascends the structure.
Statisticians and programmers primarily engage with the right side of this triangular structure, particularly with Module 5, which is dedicated to clinical data. This includes a specific subsection, Module 5.3.5.3, designated for “Reports of Analyses for More than One Study,” where Integrated Summaries of Safety and Efficacy (ISS/ISE) are included. These summaries are crucial as they compile and contextualize safety and efficacy data across multiple studies, highlighting significant findings pertinent to specific safety or efficacy issues. The integration of data in ISS/ISE allows for a comprehensive review that may utilize individual study data or pooled data from several studies, depending on the nature of the drug development project.
Further summarization occurs in modules such as 2.5 (Clinical Overview), 2.7.3 (Summary of Clinical Efficacy), and 2.7.4 (Summary of Clinical Safety), where detailed factual summaries of the clinical data presented in the CTD are provided. These summaries (SCE/SCS) distill the essence of the integrated review data, providing a critical analysis of the efficacy and safety of the drug.
Given the regulated nature of data submissions, it is essential for statisticians to not only adhere to the guidelines but also understand the nuances of data integration and pooling, tailored to the specifics of the drug development in question. The guidelines such as the FDA’s “Integrated Summaries of Effectiveness and Safety: Location Within the Common Technical Document” from April 2009, and the ICH’s “M4E Common Technical Document for the Registration of Pharmaceuticals for Human Use — Efficacy” from 2016, offer detailed instructions on structuring ISS/ISE and SCS/SCE, emphasizing the flexibility required to adapt to various drug characteristics.
The decision to utilize data pooling in drug submission projects is critical and must be made early in the process, particularly when planning the Summary of Clinical Safety (SCS) and Summary of Clinical Efficacy (SCE). Data pooling is not always mandatory; it should only be employed when it can provide deeper insights than what is achievable through individual study analyses. When considering pooled analyses, the rationale behind such an approach must be clearly articulated, and the methodological validity of combining data across different studies needs to be thoroughly justified.
Key Considerations for Data Pooling:
When approaching FDA data submissions, thorough preparation and a robust follow-through can significantly impact the successful approval of a drug.
Early Discussions with the FDA:
Engaging early with the FDA is crucial. Regular meetings to discuss the status of clinical data standards ensure alignment with FDA expectations and provide an opportunity to address potential issues proactively.
Study Data Standardization Plan (SDSP):
According to the Study Data Technical Conformance Guide, the FDA advises sponsors to draft an SDSP early in the drug development process. This plan should outline the standardized study data to be submitted and be updated continually throughout the development cycle, including any new studies or changes in data integration plans. This document is pivotal for both CDER and CBER divisions, with CBER requiring additional details for vaccine studies, such as specific SDTM mapping requirements.
The SDSP serves as a dynamic record of:
Mock Submission:
The FDA allows for a test submission of your data package to identify any technical issues or noncompliance ahead of the final submission. This test, which often includes only one study, is not about the content but rather the technical aspects of the submission. Choosing a study with complexities, such as one involving complex legacy data transformations, is advisable to maximize the feedback from the FDA’s technical team.
Post-Submission Interactions: Once the eCTD is submitted, it’s crucial to respond promptly to any FDA queries or requests for additional information. This phase is critical as timely and accurate responses can directly influence the review outcome.
Best Practices for Successful Submission:
The Bioresearch Monitoring (BIMO) program of the FDA is a critical component designed to ensure that clinical research adheres to regulatory standards. The success of FDA audits and inspections can hinge on how well sponsors prepare and provide specific data, enhancing both compliance and review efficiency.
BIMO inspections are conducted to verify compliance with FDA regulations by clinical investigators, sponsors, and Institutional Review Boards (IRB). These inspections are crucial for ensuring the integrity of the clinical research and the validity of data submitted for regulatory review.
According to FDA guidelines, particularly those specified for the planning of BIMO inspections in CDER submissions, sponsors are asked to submit three specific types of information:
Clinical Study Level Information: General details about each clinical study involved, especially for pivotal studies.
Subject-Level Data Listings by Clinical Site (By-Site Listings): Detailed listings that allow reviewers to assess data integrity and compliance at the level of individual subjects at each site.
Summary-Level Clinical Site Dataset (CLINSITE): Aggregate data summaries by site to aid in the quick review and identification of potential issues across sites.
Proactive Planning in the SDSP
Proactively incorporating anticipated requests for BIMO-related information in the Study Data Standardization Plan (SDSP) is recommended. This should include plans for how and which trials will provide detailed By-Site Listings and CLINSITE datasets, even if these requirements are primarily for major or pivotal studies. Sponsors should also consider:
Anticipating Agency Requests: The possibility of the FDA requesting additional information during the review period, even after the final eCTD submission, underscores the need for readiness in providing such data.
Automatic Generation of Listings: The FDA plans to eventually automate the generation of By-Site Listings from submitted SDTM or ADaM datasets, which will affect how data needs to be prepared and organized.
The FDA’s implementation of Technical Rejection Criteria (TRC) on September 15, 2021, marked a significant shift in the submission process for Electronic Common Technical Documents (eCTD). These criteria are designed to automatically screen and potentially reject submissions that fail to meet specific technical standards, emphasizing the need for precision in regulatory documentation.
TRCs are automated validation checks incorporated into the FDA’s inbound processing system. These criteria are intended to ensure that all submitted documents and datasets adhere strictly to specified standards. The criteria cover various aspects of the eCTD, including proper file tagging and the inclusion of essential datasets and metadata.
The TRCs for study data focus on the correct formatting and presence of specific files within the eCTD. The criteria include:
define.xml
files in specified sections of Modules 4 and 5
have the correct Study Tagging Files (STF) tags. This includes sections
dealing with both clinical and non-clinical study data.define.xml
must be included in specific sections of Module
4.define.xml
files.The Importance of ts.xpt Dataset
Regardless of the format of the data submission (CDISC or non-CDISC),
the eCTD must include a dataset named ts.xpt
in the
datasets folder. This dataset should contain at least one record with
the parameter TSPARMCD=STSTDTC
, indicating the study start
date. This is critical because the FDA system uses this dataset to
determine whether the data standards apply to your study, specifically
if the study started before or after December 17, 2016. For studies
initiated on or before this date, at least a simplified TS dataset is
required.
When preparing for an NDA submission, it’s essential to follow the FDA’s specific guidelines regarding pooled datasets and the submission of accompanying documentation in the eCTD format.
In scenarios where legacy studies (started before December 2016) are integrated into SDTM pooled datasets, the FDA provides specific guidance:
Alongside dataset submissions, the technical setup of PDF files included in the eCTD is critical. Here are the essential requirements to ensure your PDF files meet FDA standards and avoid technical rejection:
Traceability in the context of clinical data handling, particularly within CDISC standards and the ADaM datasets, plays a crucial role in ensuring the integrity and verifiability of data from collection through to analysis. This process is vital for regulatory reviews, as it allows for the clear understanding and verification of the data’s lineage—tracing back from the analysis outputs to the original data collected during the clinical study.
Both CDISC and the FDA emphasize the significance of traceability:
CDISC Definition: Traceability is described as the attribute that enables an understanding of the data’s lineage, establishing a clear path between an element and its predecessor.
FDA Guidance: The FDA highlights traceability as a critical component, often problematic in data conversions. Without effective traceability, the regulatory review process can be jeopardized, potentially impacting the evaluation and approval of a submission.
Implementing Traceability in ADaM
Traceability within ADaM can be achieved through two primary methods: data-point traceability and metadata traceability.
Preserving the –SEQ Variable: Retaining the sequence variable (e.g., AESEQ from the SDTM AE dataset) in the ADaM dataset (e.g., ADAE) to track the origin of each record.
Variable Derivations and Imputations: When variables are derived or imputed in ADaM:
Complex Derivations: For complex data transformations, using intermediate datasets can be beneficial to maintain step-by-step traceability.
Define.xml Documentation: This should include detailed metadata about the derivation of variables and the structure of the datasets.
Analysis Data Reviewer Guide: This document should outline algorithms used for data transformations and any exclusions or special handling of data points.
The document “ADaM Examples of Traceability,” released in May 2022, provides practical examples and guidance on implementing traceability across various scenarios. These examples help clarify how to maintain a clear and auditable record of data manipulations, which is crucial for regulatory compliance and scientific validity.
The evolving landscape of FDA recommendations and CDISC guidelines presents a significant challenge for data standards implementers, particularly within Contract Research Organizations (CROs) where specialization may be less common than among sponsor-side teams. The sheer volume of guidance documents and therapeutic area-specific user guides (TAUGs) complicates the implementation process, yet adherence to these documents is crucial for regulatory compliance and successful drug development and submission.
Aggregated Safety Analysis Plans (ASAPs) are comprehensive documents that outline the methods and procedures to be used for analyzing safety data across multiple clinical studies or entire programs. These plans are critical in pharmaceutical and biotechnological research, especially for meeting regulatory requirements and ensuring patient safety. Here’s what typically goes into an ASAP:
Objective: The main goal of the plan, which usually involves assessing the safety profile of a drug or treatment across different studies to identify any potential adverse effects that might not be apparent in individual studies.
Scope: Defines which studies or datasets will be included in the analysis. This might cover different phases of clinical trials, different indications, or a combination of studies conducted under similar conditions.
Data Integration Strategy: Describes how data from various studies will be harmonized and integrated. This involves standardizing data formats, coding terminologies, and resolving inconsistencies between datasets.
Statistical Methods: Details the statistical techniques and models that will be used to analyze the safety data. This includes methods for handling missing data, statistical tests for comparing adverse events across groups, and techniques for longitudinal data analysis, if applicable.
Safety Endpoints: Specifies which safety endpoints will be analyzed, such as specific adverse events, laboratory value changes, or other clinically relevant safety outcomes.
Subgroup Analyses: Outlines any planned analyses of subgroups within the data, which might include demographic categories (like age and sex), medical history, or other patient characteristics that could influence safety outcomes.
Interim Analyses and Updates: Includes provisions for interim analyses if the aggregated data will be reviewed periodically as new data become available, as well as how updates to the analysis plan will be handled.
Reporting Standards: Establishes the format and standards for reporting the results, including how detailed the safety data will be presented, the types of tables and figures to be used, and the level of detail required in textual descriptions.
Regulatory Compliance: Ensures that the plan complies with relevant regulatory guidelines, such as those from the FDA, EMA, or other regulatory bodies, concerning safety reporting in clinical trials.
The Aggregated Safety Analysis Plan (ASAP) plays a crucial role in ongoing safety monitoring and signal detection in several ways:
Ongoing Monitoring and Signal Detection: The ASAP includes methodologies for monitoring aggregate safety data from ongoing clinical trials, which might even be blinded. This systematic approach ensures continual safety evaluation, allowing for early detection of safety signals. Without such a plan, signals might not be detected until later, potentially leading to unexpected safety concerns at the end of the study.
Identifying Safety Knowledge Gaps: The ASAP prompts sponsors to identify key safety questions that may remain unanswered by the time of regulatory submission. This includes understanding the frequency and severity of adverse events, their reversibility, and risk factors, especially in specific subpopulations. By highlighting these gaps, sponsors can plan additional studies or post-marketing surveillance to address these questions proactively.
Supporting Consistent Safety Messaging: The ASAP helps establish a foundation for consistent safety messaging throughout a product’s lifecycle. It guides the creation of a “safety storyboard,” a tool (whether a slide deck or document) that evolves over time to include safety data from various stages of clinical development. This storyboard helps in aligning safety communications to regulatory bodies, healthcare professionals, trial participants, and the public. It includes identified risks with established causal associations, suspected risks, and safety concerns of interest based on epidemiology or traditional concerns, like drug-induced liver injury. It also incorporates risk minimization measures, ensuring that key safety messages are clear and consistent across all communications.
A Data and Safety Monitoring Plan (DSMP) is designed to ensure the safety of participants and the integrity of data in clinical trials. Here are the essential components that should be included in a DSMP:
A Study Data Standardization Plan (SDSP) is a critical document used in clinical trials to outline the standards and processes for collecting, managing, and reporting data in a consistent and regulatory-compliant manner. Here’s what an SDSP typically includes:
A Clinical Data Integration Plan (CDIP) is crucial for coordinating and merging data across different clinical trials or healthcare databases, ensuring seamless data analysis and supporting broader research objectives. This plan helps to manage data from diverse sources, such as clinical trial systems, electronic health records (EHRs), patient registries, and more. Here’s a detailed breakdown of what should be included in a Clinical Data Integration Plan:
In clinical research, Integrated Summary of Safety (ISS) and Integrated Summary of Efficacy (ISE) are critical components of a regulatory submission to health authorities like the FDA. These integrated summaries play a vital role in the review process for new drug applications (NDAs) or biologics license applications (BLAs). Here’s a brief overview of both components:
The Integrated Summary of Safety (ISS) and the Integrated Summary of Effectiveness (ISE) is useful for:
The ISS is a comprehensive evaluation of the safety data collected from all relevant clinical trials conducted with the investigational drug. The main objective of the ISS is to provide a complete picture of the drug’s safety profile across different patient populations, dosages, and treatment durations. The ISS should:
The ISE is a consolidated document that evaluates the efficacy of the drug based on data from multiple clinical studies. Its goal is to establish a clear and robust argument for the drug’s effectiveness across various patient populations and clinical settings. The ISE should: - Combine efficacy data from individual studies to provide overall estimates of treatment effects. - Include meta-analyses or pooled analyses when appropriate to strengthen the evidence of efficacy. - Discuss consistency of the treatment effect across different demographic and geographic subgroups. - Highlight any differences in the efficacy outcomes between the investigational drug and any control or comparator groups used in the trials.
Before integrating datasets, it is important to identify the following points but, not limited to:
Compiling Integrated Summary of Safety (ISS) and Integrated Summary of Efficacy (ISE) reports presents a range of challenges that can be complex and demanding due to the nature of data integration, the breadth of analysis required, and regulatory expectations. Here are the key challenges often encountered with ISS and ISE:
Dataset integration is a critical process in the preparation of integrated summaries for safety or efficacy, involving the pooling of data from multiple studies to produce combined statistical results. Here’s how this process typically unfolds:
There are various methods to approach dataset integration, each suited to different scenarios:
Method 1: Integrating Using Individual ADaM Datasets
Method 2: Integrating Using Study Level Tabulation Datasets
Method 3: Integrating Using Integrated SDTM Datasets
When preparing Integrated Summaries of Safety (ISS) or Integrated Summaries of Effectiveness (ISE) for regulatory submissions, the selection of the appropriate data integration strategy is crucial but can often be complex due to the lack of definitive guidance from regulatory bodies. Based on the white paper released by PHUSE in October 2020, three primary integration strategies are identified, each with its pros and cons:
Note:
Factors to Consider in Choosing an Integration Strategy
Data harmonization is a critical process in clinical research, especially when integrating data from multiple studies into a unified submission for regulatory review. Harmonization ensures that the data presented are consistent, accurate, and compliant with regulatory standards. The steps involved in data harmonization include:
Integrating data from multiple studies into a cohesive dataset for ISS (Integrated Summary of Safety) or ISE (Integrated Summary of Effectiveness) submissions involves several critical considerations to ensure consistency, compliance, and clarity in the final analysis. Here’s an in-depth look at the key factors and recommendations for successful data integration: