Phases of Clinical Trials for Diagnostics
Research for new diagnostics used to diagnose or monitor medical conditions, such as a genetic test or imaging technique, follows a structured process with clearly defined steps (phases).
Trial Participants | Trial Endpoints | Regulatory Pathways | Post-Market Surveillance |
|---|---|---|---|
Patients with the target medical condition and, sometimes in early phases, healthy volunteers. | Typically related to the disease or condition such as symptom improvement, disease progression, or survival rates. | In the United States, clinical trials for drugs are governed by agencies like the Food and Drug Administration (F.D.A.). | Monitoring of safety and efficacy in real-world settings. |
Trial phases focus on validation & comparison to standards
The ability to provide accurate and reliable test results involves comparisons with established standards of diagnosis as well as regulatory review, though the specifics vary depending on the nature of the diagnostic tool.
Steps commonly involved in clinical trials for a new diagnostic
Phase 0: Development & feasibility assessment
Researchers and developers work to create and refine the diagnostic test or imaging technique. Any preliminary studies are conducted in a laboratory or with limited patient samples.
Objective: Evaluate feasibility, accuracy, and potential clinical utility.
Methodology: Lab tests, analysis of specificity and sensitivity, and other approaches.
Validation studies
Researchers test technical performance, including sensitivity, specificity, precision, and reliability. Well-defined patient samples are used to assess the ability of the diagnostic to accurately detect or measure a target biomarker or condition.
Objective: Rigorously assess the diagnostic tool in a clinical setting.
Methodology: Compare to a “gold standard” diagnostic method such as an MRI for brain tumor diagnosis.
Phase I: Exploratory clinical studies
Also known as early phase studies, exploratory studies typically involve a small number of participants, often with the target condition and a control group without the condition.
Objective: Gather data on diagnostic performance in a clinical setting, including the sensitivity and specificity of the diagnostic.
Outcomes: Parameters and algorithms of a diagnostic may be refined based on these early findings.
Analytical & clinical validation studies
Researchers conduct large-scale studies with a diverse and representative patient population.
Objective: Assess the accuracy, safety, and clinical utility of a diagnostic.
Methodology: Compare diagnostic results to a reference test to establish the clinical validity and performance characteristics.
Regulatory submission & review
Data from clinical trials are compiled and submitted to regulatory agencies for review and approval. For example, in the United States, the F.D.A. oversees the approval of diagnostic tests.
Objective: Evaluate the test’s safety, accuracy, and clinical performance before granting market clearance or approval.
Outcomes: Approval, delay (e.g., sponsor may need to conduct additional studies), or denial (e.g., unexpected safety issues, failure to demonstrate effectiveness) by the regulator.
Phase IV: Surveillance
Post-market surveillance studies occur after approval or clearance of the diagnostic test via ongoing data collection.
Objectives: Identify unforeseen issues, assess long-term performance, and ensure the test remains safe and effective.
Focus: Monitor real-world clinical application and results.
Optional comparative studies
In some cases, additional research may be conducted to assess diagnostic performance compared to existing tests or techniques. These studies can provide valuable information about the diagnostic’s added benefits or limitations.
Periodic updates & refinements to diagnostics
In order to improve diagnostic performance or address emerging clinical needs, a phase or phases may be repeated. The specific step(s) and requirements vary depending on the nature of the test, the target condition, and the regulatory landscape in the country where the trials are conducted. The ultimate goal is to demonstrate that the diagnostic is safe, accurate, and clinically valuable for diagnosing or monitoring a specific medical condition. There are similar phases for medical device trials.
Need help?
We can guide you to a clinical trial that’s actively recruiting
Finding the right clinical trial can be intimidating. And time consuming. Which is why Unity Trials provides a unique concierge service for people interested in medical research.