Manufacturing

Design Control: Importance And Regulatory Aspects

During all the stages of the development, the “Design reviews” of the activities shall be performed by the team members and the peer reviewers to check if the project is being moved to achieve the user needs. The comment from the reviews will determine the changes in the plan or the design and shall be circulated to all the team members.

The adequacy of the design output against each of the design input shall be demonstrated. It can be achieved through the set of experimentation and the activity is called as “ Design Verification”. The design verification activity shall be done by creating the test cases for each of the design output and corresponding input. The typical example of the verification studies may be technical, physical, chemical characterization or other engineering analysis, bench testing etc. The test protocols are approved before execution and are executed and data collected. The compilation of the data shall be done to interpret the results in the “Summary report” The report shall be reviewed to check if the design output is giving the expected design input expectations. In case, design output attributes fails to achieve the desired expectations laid down in design inputs, then it may call up for the changes in the design. All the changes shall be documented through the “design change requests” which shall be approved by all the team members. Once the change request is approved, then design outputs and/or design is changed with the aim to achieve the expectations given in the design inputs. The repeat verification is performed to recheck if the expected design inputs are being achieved.

It is necessary to verify if the device achieves the user needs before launch of the device in market for commercial use. The activity is called as “Design Validation”. The typical example of the validation studies may be simulated product study, clinical trials, bench testing, Animal studies, reliability studies, usability studies, market surveys etc. The studies are carried out on the production equivalent. The validation plan shall be approved and studies conducted. The studies carried out are adequately documented and reports are prepared. The data collected during the validation activities are used for 510 (k) submission, Technical File, Device Master File etc. The risk analysis and usability studies on final product shall be performed to know, the exact status of the designed product going and suitability of the same for commercial purpose. The output of the risk analysis and usability studies can contribute to make the “Instruction for use” (IFU). The relation ship between design verification and validation can be determined in Figure 2 :

The design verification determines “If we design the product right” and design validation determines “If we design the right product”.

The compilation of all documentation done during the design and development activity is called as “Design History File” (DHF). The DHF is the dynamic document and shall be amended as the changes in the design happen based on the market performance of product. The Corrective and preventive actions arising from the various sources related to product performance may lead to design changes and the activity performed is amended in the DHF.

The design transfer shall be performed to the commercial manufacturing site, the activity is called as “ Design Transfer”. It is the effort to transfer the “know-how” and experience gained during the design and development activity. The design transfer involves the transfer of the Raw material specification, Finished goods specifications and test methods, Test equipment, Process flow charts, manufacturing machines and utilities specifications, In-process test parameters, release p arameters, vendor details, labeling details, Instruction for use, Primary and secondary packaging material details etc. The document in which this is mentioned is called as “Device Master record” (DMR). The relationship between DHF, DMR and DHR is shown on figure 3:

Figure 3: The relationship of the DHF, DMR and DHR can be shown in below schematics:

The DMR becomes the basis to formalize the “ Device History record” (DHR). The DHR provides the adequate traceability for the commercial batches manufactured. In case of the customer complaint or any adverse events, the complete batch history can be traced through DHR.

The continual and deliberate efforts shall be made to collect data from users about the performance of the product and to evaluate the impact of the residual risks posed to the customer the activity is called as “Post market surveillance” (PMS). The adequate post market surveillance will help to “Fine tune” the design of the product and put added features to the device to improvise the device.

The design and development activity plays a vital role in the total lifecycle of the device. This necessitates the regulators and certifying bodies to have the detailed review of the design and development documentation to ensure compliance.