clinical endpoints

By Ethical 21 Feb, 2024

Different Types of Clinical Endpoints and How to Assess Them?

A clinical study endpoint refers to a predefined outcome or event that is used to determine the success or failure of a clinical trial. Defining clinical endpoints is vital for measuring treatment effectiveness, comparing different interventions, and obtaining regulatory approval, but can present several challenges. Well-defined endpoints provide the necessary data to support the approval process and ensure that only safe and effective treatments reach the market. Endpoint adjudication is the procedure by which clinical events identified as potential endpoints are submitted to a panel of independent experts to be assessed in a blinded way. The procedure can be cumbersome and is greatly facilitated by a user-friendly software tool such as Ethical’s eAdjudication®.

The different types of clinical endpoint 

Clinical endpoints refer to the specific outcomes or events that are measured to determine the effectiveness or safety of a treatment. Endpoints can vary depending on the nature of the trial, but commonly include measures such as disease progression, mortality rates, or improvement in symptoms.

Primary endpoints are the most important outcomes or events in a clinical trial. They are the key focus of the study and are used to determine the treatment's overall efficacy. 
The selection of primary endpoints depends on various factors, such as the therapeutic area, treatment goals, and available measurement tools. Primary endpoints are typically measured objectively and quantitatively. They provide the most direct evidence of a treatment's effectiveness and serve as the basis for regulatory decisions and clinical practice guidelines.

Secondary endpoints provide additional information that helps researchers gain a more comprehensive understanding of the treatment's effects. Secondary endpoints can include a wide range of outcomes, such as specific symptoms, biomarkers, or quality of life measures. 
While secondary endpoints do not carry the same weight as primary endpoints in regulatory decisions, they complement the primary endpoints and provide a more comprehensive picture of the treatment's effects, contributing to the overall understanding of the treatment's benefits and potential side effects. 

Surrogate endpoints are outcomes or events that are used as substitutes for the actual clinical outcomes of interest. They are used when measuring the primary endpoint directly is impractical, time-consuming, or ethically challenging. Surrogate endpoints act as indirect indicators of patient outcomes. Using surrogate endpoints has its advantages, such as shorter trial durations and reduced costs. However, strong scientific basis and correlation with the desired clinical outcomes are evaluated by regulatory bodies when considering treatment approvals. 

Patient-reported outcomes (PROs) are another important type of clinical study endpoint. PROs capture the patients' perspectives on their symptoms, functioning, and quality of life. 

PROs can include questionnaires, surveys, or interviews that assess various aspects of the patient experience, such as pain levels, physical functioning, emotional well-being, and treatment satisfaction. By incorporating PROs as endpoints, researchers can better understand the patient's lived experience and the true impact of the treatment on their daily lives. 

Challenges in Selecting Clinical Endpoints

Selecting and measuring clinical endpoints can present several challenges.

Firstly, Researchers and regulatory bodies may have different perspectives on what constitutes a meaningful clinical outcome. This lack of consensus can lead to variability in endpoint selection across studies and difficulties in comparing treatment effectiveness.

Secondly, measuring certain endpoints can be challenging due to their subjective nature or the lack of reliable measurement tools. Patient-reported outcomes, for example, rely on patients' self-assessment and may be influenced by various factors such as recall bias or social desirability. Developing valid and reliable measurement tools for subjective endpoints is an ongoing research endeavor.

Lastly, clinical endpoints need to be sensitive to detect clinically meaningful differences between treatments. If the selected endpoints are not sensitive enough, the study may fail to demonstrate the treatment's effectiveness, even if it has true clinical benefits.

Ensuring that the chosen clinical endpoints are appropriate and adequately capture the treatment's impact is crucial for reliable study results. 

Assessing clinical endpoints

An independent panel of experts, known as the adjudication committe, carefully examines all relevant information, including medical records, laboratory results, and imaging studies, to make a conclusive determination regarding the occurrence and severity of the clinical event. The purpose of clinical endpoints adjudication is to provide an unbiased evaluation of the clinical endpoints, ensuring that the data collected is consistent and reliable. 

An important aspect of adjudication is the establishment of standardized criteria for evaluating clinical endpoints. These criteria are developed prior to the start of the trial and guide the adjudication committee in their decision-making process. The criteria provide clear definitions and guidelines for assessing the occurrence and severity of specific events, ensuring consistency across different sites and investigators.

The adjudication process can be quite cumbersome. An electronic tool such as Ethical’s eAdjudication® software solution helps manage smoothly and efficiently all adjudication operations by connecting the key adjudication actors, supporting data manageability, quality and security, streamlining workflow, and simplifying process governance.


In conclusion, clinical endpoints are crucial elements in evaluating the effectiveness of new drugs and treatments. From primary endpoints that focus on the main objectives of a study to secondary endpoints that provide additional insights, each type of endpoint contributes to the overall understanding of a treatment's impact.

When reviewing clinical trial data, regulatory agencies consider the endpoints used and their relevance to the disease or condition being studied. They assess the validity, reliability, and clinical significance of the endpoints to make informed decisions about treatment approvals.

The adjudication of clinical endpoints plays a vital role in ensuring the integrity and validity of clinical trial data. Clinical teams greatly benefit from a tool like Ethical’s flexible, GCP-compliant, cost-effective and easy to use eAdjudication® software solution that supports operational excellence.

Clinical Endpoint Examples

Clinical study endpoints vary depending on the therapeutic area being investigated. Here are a few clinical endpoint examples in different therapeutic areas:

1. Oncology: Overall survival, progression-free survival, tumor response rate, time to progression.
2. Cardiovascular Disease: Major adverse cardiovascular events, cardiovascular mortality, hospitalization for heart failure.
3. Infectious Diseases: Time to viral clearance, reduction in pathogen load, prevention of disease transmission.
4. Neurology: Improvement in cognitive function, reduction in seizure frequency, motor function improvement.
5. Rheumatology: Reduction in joint swelling and tenderness, improvement in physical function and quality of life.
6. Psychiatry: Reduction in depressive symptoms, improvement in anxiety levels, treatment response rate.

These clinical endpoint examples illustrate the diverse range of endpoints used in clinical trials across various therapeutic areas. The selection of endpoints depends on the specific disease or condition being studied, the treatment goals, and the available measurement tools. 

The Complete Manual / Reference Book (34 pages) with all the topics related to the Independent Endpoint Adjudication Committees Management

Endpoint Adjudication Process, How to Manage Endpoint Adjudication Committees


Download Ethical eAdjudication for Endpoint Adjudication Dossier

Solution Description


Request a Demo of the eAdjudication® Software Solution

We are EU-GDPR compliant: Your Data will never be used improperly

Event Adjudication Charter Guide

Event Adjudication
Charter Guidebook
Free Download

Previous Next

Key Requirements for ISO/IEC 27001  Compliance in Clinical Trials

ISO/IEC 27001 is an internationally recognized standard for information security management systems (ISMS) that serves as a tool for risk management, cyber-resilience and operational excellence. [...]

ISO certificateREAD MORE

How Ethical’s eAdjudication® supports successful endpoint adjudication

Let’s review the software-integrated six-step process that supports endpoint adjudication performance.

endpoint adjudication processREAD MORE

Training the Endpoint Adjudication Committee Members

It comes to the sponsor to ensure that EAC members are adequately trained (and occasionally re-trained) in the procedures and approaches of the particular study.

Training the Endpoint Adjudication CommitteeREAD MORE