Medical Device Clinical Trials
Based on the region, there are a variety of classification systems, and definitions and requirements for medical devices also vary.
The US Food and Drug Administration (FDA) is responsible for overseeing every step, including clinical trials, to ensure that medical devices meet safety and effectiveness standards before they are marketed.
The article below will review the classification of medical devices and discuss which clinical trials need to be conducted and how they are conducted.
The Definition of Medical Device
Medical devices encompass a wide range of products, from simple, small items like thermometers to complex, large-scale MRI machines.
According to the FDA, the medical device is āan instrument, apparatus, contrivance, implant, in vitro reagent or other similar or related articleā that is used alone or in combination for one or more of the following medical purposes:
- Diagnosis, monitoring, alleviation, treatment or prevention of diseases or injuries
- The investigation, modification, replacement or support of the anatomy or physiological processes
- Control of conception
- Supporting or sustaining life
Medical devices do not achieve their principal intended purposes by chemical action or by being metabolized.
Classification of Medical Devices and Control Measures
There are more than 1500 different types of devices on the FDA list. Based on the risks of the device use and the level of control necessary to assure safety. All of them fall into one of the 3 categories:
Class I (low risk)Ā ā Out of all medical devices, 47% fall into this category and most are subject to general controls, with some exempt from premarket notification requirements. Gauzes, toothbrushes, bandages, and stethoscopes fall into this category.
Class II (moderate risk)āApproximately 43% of medical devices, including suture needles, contact lenses, catheters, and surgical gloves, fall into this category. Pregnancy test kits are also Class II devices but require special controls for approval.
Class III (high risk) ā Itās the smallest group, containing devices that support or sustain life, are implanted, or present an unreasonable risk of illness or injury. This includes pacemakers, heart valves, and implantable defibrillators. HIV test kits are generally Class II devices.
Pacemakers, ventilators, angioplasty catheters, heart valves, and various other types of implants are classified as Class III.
As we can see, the risks increase from I to III, and so do the regulatory controls. Class I devices can be subjected to general control only.
Class II devices require special controls for approval, while Class III, high-risk devices need general controls, special controls, and premarket approval.
You can find more information about these regulatory controls at FDA.gov. To cut a long story short, clinical trials may not be required for some devices. But they are an absolute necessity for all class III and some class II devices.
How are Clinical Trials Initiated?
To conduct a human study in the US, the FDA requires submission and FDA review of an Investigational New Drug (IND), with most reviews completed within 30 days.
Before the FDA gives this approval, multiple factors need to be considered: the background of medical issues, detailed description of the device, previous preclinical and clinical studies, careful risk analysis, patient monitoring and follow-up plan, sample size, and inclusion and exclusion criteria, etc.
After the review, the FDA can decide to approve the trial, disapprove it, or approve it with conditions.
In the latter case, the trial can start if the sponsor agrees to address all conditions listed in the approval letter within 45 days.
The FDA can approve IDE applications for various types of clinical trials, such as early feasibility studies, pivotal studies, and studies under the Safer Technologies Program (STeP). The exact descriptions are below.
Clinical Trials
- Early Feasibility Study (EFS) ā It may include fewer than 15 patients. This type of trial is for devices that are in the early stage of development, and the device design is not final; hence, the approval of EFS IDE may be given based on insufficient clinical data.
- Feasibility study ā A small clinical trial, often including 20 to 100 subjects, designed to provide preliminary data on the deviceās safety and efficacy. Instead, it focused mainly on patient safety. Feasibility studies are often required by the FDA to assess the safety and answer basic research questions before they permit conducting the larger pivotal study.
- Pivotal study ā A larger study that typically follows a successful feasibility study, designed to gather sufficient evidence on safety and effectiveness to support a marketing application. Endpoints and sample sizes are statistically driven and provide support for marketing applications. The FDA review here is much more complex than in the case of previous trials.
- Post-approval study ā even if the FDA approves a medical device, further studies are often required to obtain long-term data, especially for Class III and some Class II devices.
Does Successful Study Imply Device Approval
The short answer is often, but not always. Sometimes, alternative clinical or non-clinical data may conflict with study results, or serious safety concerns may be observed in subsequent clinical trials.
This may lead to disapproval or approval with limited indication and the requirement for new, reliable data.
In turn, the study failure does not always lead to premarket approval application disapproval, since the FDA claims it is always willing to review all available data to determine whether there is a reasonable assurance that the device is safe and effective
Take-home Points
Not all medical devices require clinical trials to get FDA approval. Companies need to grant IDE approval to conduct clinical trials in the U.S.
There are multiple types of clinical trials, with separate goals, like proving subsequent studiesā safety or demonstrating the deviceās effectiveness.
In general, medical device clinical trials include fewer subjects than drug studies.
See Also
Clinical Research Project Manager
Clinical Trials Patient Retention
Durable Medical Equipment Suppliers