TX Q&A

The detection system for in vitro diagnostic reagents refers to a combination that includes products for sample processing, test reagents, calibrators, quality controls, and testing equipment, capable of completing all stages from sample processing to the final result report. The entire detection system undergoes a thorough safety and efficacy evaluation and is approved for use. During the product registration process for in vitro diagnostic reagents, it is possible that not all other products needed to complete the testing are included. In such cases, it is necessary to clearly specify the accompanying products in the instructions manual to ensure that the testing is conducted according to the detection system composed of all supporting products. For example, for nucleic acid test reagents that do not include extraction reagents, the extraction reagents specified in the manual must be used during performance evaluation and clinical evaluation.

In October 2020, the National Medical Products Administration issued an announcement (2020 No. 112) regarding adjustments to some contents of the "6840 Sub-catalog of In Vitro Diagnostic Reagents Classification (2013 Edition)." The management category for some tumor marker-related reagents used for therapeutic monitoring has been adjusted to Class II. The tumor marker-related reagents used for auxiliary diagnostic purposes in the "6840 Sub-catalog of In Vitro Diagnostic Reagents Classification (2013 Edition)" have not undergone category adjustments and continue to be managed as Class III.

According to the current GB/T 16886 "Biological Evaluation of Medical Devices" series of standards, the overall biological evaluation should consider the following aspects: (1) materials used in manufacturing; (2) expected additives, process contaminants, and residuals; (3) leachable substances; (4) degradation products (if applicable); (5) other components and their interactions in the final product; (6) performance and characteristics of the final product; (7) physical properties of the final product, including but not limited to porosity, particle size, texture, and surface morphology. Based on the clinical intended use of the product, the biological evaluation should consider the cumulative duration of use, in accordance with the requirements for prolonged contact between the external device and circulating blood. If the product uses new materials, or may contain carcinogenic, mutagenic, and/or reproductive toxic substances, it is also recommended to consider related endpoints in the risk assessment.

Applicants for registration must provide verification data related to the functional compatibility of the product with the injection pen. Generally, this includes verification of needle hub assembly, dose accuracy, and needle hub disassembly torque. The needle head is connected to the injection pen by applying a specified torque, and the integrity of the clinically relevant fluid pathway is confirmed through dose accuracy testing. The disassembly torque of the needle hub is also measured and recorded. Additionally, a rationale should be provided for the number of products verified, clarifying parameters such as confidence levels and reliability.

Polyurethane foam dressings with adhesive backing are included in the "Catalog of Medical Devices Exempt from Clinical Evaluation." However, it is important to note that the exemption from clinical evaluation does not apply to the following situations: 1) Products claimed to promote epithelialization, guide tissue regeneration, enhance wound healing, relieve pain, stop bleeding, reduce scarring, prevent adhesion, etc.; 2) Products claimed to be used for internal wounds, third-degree burns, infected wounds, wounds with extensive necrotic tissue, patients with wound sepsis, etc.; 3) Products containing active ingredients such as drugs/pharmaceutical active ingredients, biological products/biological active components, silver, disinfectants, etc.; 4) Other novel products.

Risk assessment for medical devices that utilize nanomaterials should be conducted according to GB/T 16886.1 "Biological Evaluation of Medical Devices Part 1: Evaluation and Testing within a Risk Management Process," YY/T 0316 "Application of Risk Management to Medical Devices," and "Medical Device Product Benefit-Risk Assessment Registration Technical Review Guidelines." It is crucial to consider risk factors such as the potential for nanomaterials to be released from the device, exposure dose, routes of exposure, contact sites, and exposure duration. The most critical factor in the risk assessment is the likelihood of nanomaterial release from the medical device. The risk assessment should be conducted in stages and systematically, taking into account exposure assessment (release of nanomaterials), distribution and persistence of nanomaterials, environmental transformation, and hazard identification. Finally, the overall risk of the product should be considered in light of the scope of its use and whether it provides sufficient benefits to the patients.

Clearance rate is a primary functional parameter of dialyzers and a key indicator for evaluating the quality of dialyzers. Commonly used indicators for evaluating the clearance performance of dialyzers include urea, creatinine, phosphate, and vitamin B12. For high-flux dialyzers, performance testing and clinical evaluation data for β2-microglobulin clearance should also be provided. According to the mandatory industry standard YY 0053 "Blood Dialysis and Related Treatments: Blood Dialyzers, Blood Dialysis Filters, Blood Filters, and Blood Concentrators," high-flux hemodialysis should evaluate the β2-microglobulin clearance rate at clinically common blood flow rates, and a single blood flow rate can be selected for this assessment.

For metal materials used in additive manufacturing processes such as laser selective melting, it is crucial to first clarify the methods and parameters of heat treatment. The suitability of these heat treatment methods should be assessed and verified. This includes establishing the basis for determining heat treatment parameters, such as heating time, holding time, and holding temperature. Additionally, criteria for the acceptability of the results after heat treatment should be clearly defined.

When selecting the worst-case scenario samples for the mechanical performance of intervertebral fusion devices, consider the impact of various factors such as the size of the bone grafting area, side hole dimensions, angle, length, width, and height of different models and specifications of the fusion devices. Additionally, the model and specifications of the worst-case scenario samples may vary depending on the mechanical performance indicators, such as compression, compressive shear, and torsion. Considerations should be made in conjunction with the methods and loading modes of dynamic and static mechanical performance tests for cervical and thoracolumbar intervertebral fusion devices, to comprehensively determine the selection of the worst-case scenario samples.

Biological evaluation cannot be exempted outright. However, equivalence comparisons can be used to demonstrate that the product under application has the same biocompatibility as an already marketed product, thereby potentially reducing or exempting the need for biological testing of the application product. Even though materials compliant with YY 0341.1 Appendix B are clinically proven to be acceptable, equivalence comparisons are still necessary. For instance, it should be demonstrated whether the manufacturing process introduces new biological risks. This includes comparing both products' manufacturing processes, such as processing, sterilization, and packaging, as production processes can introduce new harmful substances, such as residues from sterilants, processing aids, or release agents. If the evaluation determines that the manufacturing process does not introduce new biological risks, then biological testing may be exempted.