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iological safety of the medical device is an important requirement for market approval. It is important for a medical device manufacturer to evaluate the potential risk of a medical device to a patient or user. This evaluation alone does not suffice, the medical device manufacturers need to address the potential risk of the medical devices. In order to address this issue, medical device manufacturers have developed a biological safety evaluation program. The biological safety of medical devices shall be evaluated by the manufacturer over the whole life cycle of a medical device.

The objective of biological safety evaluation program is to identify unacceptable biological risk. Biological risk means the probability of harm to health occurring as a result of adverse reactions associated with the medical device and medical interactions and the severity of the harm.  The importance of the biological safety evaluation is based on various risks impacting the biological response of the human body to a medical device.

All risks, known and unforeseeable, and any undesirable side effects need to be minimized and brought to an acceptable level when weighed against the evaluated benefits of medical device to a user during the normal condition.

Biological Evaluation and US FDA 510k

One of the main intentions of medical device regulation is to ensure that medical devices are biocompatible. Several biological and nonbiological risk can be associated with a lack of biocompatibility in a device. The cause of these risk can be a potential source of harm once they get in contact with the human body. Hence, biocompatibility is an integral part of biological risk assessment; biocompatibility testing assesses the compatibility of medical devices with a biological system. The area of risk discussed under biocompatibility is not based on the function or use of the device, but on the material and manufacturing process. Hence, this evaluation is done mainly when a new device is invented or developed and when a manufacturer makes a change to a device. For example, if a manufacturer wants to change the sterilization method of the medical device, then biological evaluation needs to be done to assess potential risk associated with this change on biocompatibility. This is also assessed when company decides to change the colorant of the device for marketing purpose.

Medical device manufacturers should refer the ISO 10993-1 as their guide to meet regulatory requirements related to the biocompatibility of the medical device. Medical device manufacturers can critically evaluate their medical devices based on endpoints while at the same time classifying them based on the nature of the body contact, they have with the living bodies and the duration of the body contact. ISO 10993-1 does not recommend the use of animal experiments to check the biological safety of the medical device. Instead, it urges the manufacturers to carryout material characterization of the medical device.

The endpoints required for the evaluation of biological safety; the manufacturers use to evaluate the information about evaluating the endpoints of a medical device which can come in contact with the human blood. These are the endpoints. Physical or chemical information, cytotoxicity, sensitization, irritation, material mediated pyrogenicity, Acute systemic toxicity, chronic toxicity, implantation effects, hemocompatibility, carcinogenicity, reproductive or developmental toxicity, and degradation.

Medical devices comprise multiple components, each will have physical and chemical properties. Inherent varying complexity, risk of injury, and toxic effect of human notified body to expect biological safety evaluation process. This must include physical and chemical characterization, and biocompatibility testing to assess all relevant biological endpoints. It is important to bear in mind that biological safety is not the same as biological equivalence. Manufactures will provide all available information’s on the materials used to evaluate their biocompatibility , examples are material data sheet, certificates, result of research on known ingredients and additives , market experience.