Functionality assessment, combination biologic

Assessment of biologic/device combination product functionality needs to include all of the testing typically performed on bare metal stents (BMS). In the case of our antibody-coated stent model the BMS have been previously approved by CDRH, allowing some of the BMS data to be cross-referenced and not repeated when the effect of the antibody coating on the functionality of the device is considered negligible. These judgments must be made on a case-by-case basis and should be confirmed with the Office for Device Evaluation. 

Structure and function need to be jointly considered in the assessment of effects of stressors on river systems. It has been shown that the two sets of parameters offer complementary information since they cover different time scales and responses. This being shown in the case of biofilms is not a unique characteristic of them, but it might be applied to all other biological communities (e.g. macroinvertebrates, fish). These differ from the biofilm in its higher size and life span, and therefore in their integrative capacity to reflect effects in one part of the ecosystem. Higher traffic levels in addition to biofilms should be considered to study the whole ecosystem. In all of these biological compartments, the combined use of descriptors may amplify our ability to predict the effect of stressors on river basins. 

The Sediment Quality Triad (SQT) is an effects-based conceptual approach that can be used to assess and determine the status of contaminated sediments based on biology (laboratory and/or in situ toxicity tests), chemistry (chemical identification and quantification), and ecology (community structure and/or function). It provides a means for comparing three different lines of evidence (LOE) and arriving at a weight of evidence (WOE) determination regarding the risk posed by contaminated sediments. Effectively, each LOE comprises an independent assessment of hazard combined and integrated, they provide an assessment of risk. 

If the device component of the biologic/device combination product has already been cleared or approved as a stand-alone product, some aspects of device functionality will be known. However, the effect of the biologic will need to be investigated. In the case where the device and biologic are physically associated with each other, the process used to join the two components can affect device performance in a variety of ways. Easily determined parameters such as dimensions and clearances must be confirmed. More subtle issues arise when physical performance and durability are assessed. Additional manufacturing procedures associated with the antibody coating could, at least in theory, alter the properties of the entire device. In some cases, test methods that have been successfully employed for stand-alone devices may need to be modified to accurately assess all relevant parameters that must be considered for the combination product. 

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