Medical devices clinical safety evaluation

As a general rule, clinical data are required as evidence to support conformity with the requirements of the Active Implantable Medical Devices (AIMD) and the Medical Device (MD) directives with regards to safety and effectiveness under the normal conditions of use, evaluation of undesirable side effects, and the acceptability of the benefit/risk ratio. Risk analysis should be used to establish key objectives that need to be addressed by clinical data, or alternatively to justify why clinical data are not required (mainly for Class I devices). The risk analysis process should help the manufacturer to identify known (or reasonably foreseeable) hazards associated with the use of the device, and decide how best to investigate and estimate the risks associated with each hazard. The clinical data should then be used to establish the safety and effectiveness of the device under the intended use conditions, and to demonstrate that any of the residual risks are acceptable, when weighed against the benefits derived from use of the device. 

Studies to investigate the safety and effectiveness of In Vitro Diagnostic (IVD) medical devices under intended use conditions are conducted as performance evaluations. They are considered to present less risk than clinical investigations since, by their nature, studies involving IVDs cannot have any direct impact on the health and safety of trial subjects. 

For any intervention intended to impact favorably upon human health, it is important to evaluate its safety and efficacy in order to demonstrate that it does not cause harm and it does provide the expected benefit. The gold standard method for evaluating any intervention, whether it be a botanical product, dietary supplement, drug, medical device or medical procedure, is the randomized, clinical trial (RCT). A clinical trial is a type of experiment conducted in human subjects where the effects of at least two interventions are compared. Often, the clinical trial takes the form of an active treatment compared to an inactive control or placebo. 

Clinical trials are studies to evaluate the effectiveness, pharmacokinetics, and safety of medications or medical devices by monitoring their effects on large groups of people. Clinical research trials may be conducted by government health agencies, researchers affiliated with a hospital or university, independent researchers, or private industry. The use of an approved medicinal product in nonapproved conditions (different administration route, dose, clinical indications, etc.) requires also a new clinical trial. 

Although the Editors and contributors frequently refer to synthetic and, in some cases, processed natural materials as biomaterials, nothing herein should be taken as either an implied or explicit warrantee of the usefulness, safety or efficacy of any material or any grade or variation of any material in any medical device or surgical implant. Such determinations are an intrinsic part of the design, development, manufacture and clinical evaluation process for any device. Rather, the materials listed here should be considered, on the basis of their intrinsic properties and, in many cases, prior use, to be candidates to serve as biomaterials possibly to become parts of successful devices to evaluate, direct, supplement, or replace the functions of living tissues. 

It is unnecessary to state that contact lenses are considered to be a medical device. As this is the ease, very strict evaluation by every country where they are used is required regarding both safety and effectiveness. These are restrictions and standardizations placed on any medical device. The European Union (EU) in recent years established international standards (ISO) touching upon the material, product, performance, biosafety tests, and clinical trials. 

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