In general, a clinical evaluation is expected for any device regardless of risk category. Clinical evaluation of a MD is completed before it is placed on the market and throughout its lifetime. Clinical evaluation may take different forms and you can conduct clinical investigations for your device.
Many people mistakenly think that the design of clinical trials is identical for drugs and medical devices. Below we will clarify the differences and similarities in the design of clinical trials so you have a greater ability to manage your future clinical trials.
There are 4 phases of clinical trials for drug evaluation. Let’s compare these phases to those of the medical device.Phase 1 (Pharma) and « Feasibility Study » (MD)
Phase 1 is the first trial of the medication on human. This phase is carried out on healthy subjects, except for highly toxic products such as in Oncology. The objective is to evaluate the safety of the product’s use, its fate in the body, and its tolerance threshold and adverse effects. It is performed on 20-100 subjects. For an MD, this preliminary phase is called the “Feasibility Study” and it is performed on a reduced number of patients (between 10 and 30).Phase 2-3 (Pharma) and « Pivotal » Study (MD)
Phase 2 is performed on patients. Its objective is to test the effectiveness of the product and determine the optimal dosage. It is carried out on a larger number of patients.
Phase 3 called « Pivotal » is performed on 100 to 1000 patients and it allows comparison between the therapeutic efficacy of the molecule to the standard treatment or to a placebo.
In the MD, these two phases (2 and 3) are combined into a single phase called the « Pivotal Study ». It is generally carried out on 100 to 300 patients and evaluates the efficacy and the safety of the MD.
Phase 4 (Pharma) and “Post-Marketing Clinical Follow-up (PMCF) Study”
Phase 4 aims to identify possible rare side effects of medications not detected in previous phases (pharmacovigilance) and specify the conditions of use for certain groups of patients at risk. During this phase, the MD and the drug merge completely. The only difference is that the term Phase 4 does not exist in for MDs. The term « PMCF study » roughly corresponds to “post-registration study” for Phase 4 studies on drugs.
For drugs, long term data will be collected and the focus will be on unexpected adverse effects. For MDs , PMCF studies will often focus on effectiveness (efficacy in real life) and emerging risks, especially if the technology is still evolving.
The methodological design of clinical studies on MDs and on drugs has many similarities and some differences. While the MD has 3 phases of clinical investigations, the drug has 4. In addition, the number of patients participating in MD studies is generally more modest.
However, the way forward is the same between the different products; it allows achieving the same result : the patient’s safety.
Written by Vanessa Montanari
Pharmaspecific, see her on Linkedin