risks. As regards prior use data, once again the site and duration of exposure of the new device compared to the prior use should be kept in mind. These data provide either an estimate of risk in line with Clause 4.4 of EN/ISO 14971 or a measure of the acceptability of risks in line with Clause 4.5, respectively.

Acceptable results from appropriate biological tests, of the sort described in the EN/ISO 10993 series of standards, may give a degree of reassurance that the risk of adverse reactions occurring during clinical use is low. EN/ISO 10993-1 indicates evaluation tests which can form a framework for the development of an assessment programme. These tests, commonly termed biocompatibility tests, differ from basic toxicity tests in that they typically attempt to mimic the conditions of clinical exposure to medical devices and thus provide an indication of the probability of adverse effects arising during use. They tend, as a result, to be less sensitive than basic toxicity tests and are thus a less discriminating indicator of risk. Biocompatibility test data should therefore be used to complement an assessment based on materials characterisation, rather than as a replacement for it.

It may not be necessary to perform tests suggested by the standard in all cases. Where the proposed materials have already been extensively used or tested, little or no biological testing may be necessary to judge the biological safety of the device. Conversely, the need for additional tests such as mutagenicity or metabolism studies should be considered on a case by case basis. National laws may prohibit unnecessary animal tests and the need for testing should always be judged in relation to the predictive value of the test and animal welfare considerations.

At GLR we offer comprehensive program of biological safety assessments, literature search, identify data gaps and biocompatibility testing. Our scientists have extensive experience in risk assessment and safety evaluation of all classes of medical device and can offer expert advice on how to go about testing of medical devices.

We are providing some basic information on biocompatibility ie., classification of medical devices. These information will be very useful when placing biocompatibility tests. Please feel free to contact us if you have any questions.

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