What should be noted about the types of extraction media for biological experiments?
According to the provisions of the GB/T 16886 series standards, when conducting biological experiments, the selected extraction media should be suitable for the characteristics and use of the final product as well as the purpose of the experiment, taking into account the material chemical properties of the device materials, extractable substances, or residues. For cytotoxicity tests, as serum-containing culture medium is a necessary medium that supports cell growth in the test system and has the ability to extract both polar and non-polar substances, it should be considered as the preferred extraction medium for cytotoxicity tests. In this case, only one extraction medium containing serum culture medium can be used. For sensitization tests, irritation or intracutaneous reaction tests, acute systemic toxicity tests, etc., consideration should be given to selecting both polar and non-polar extraction media. For genetic toxicity tests, according to the GB/T 16886.3 standard, when appropriate, two suitable extraction solvents should be used—one polar solvent and the other non-polar solvent or a liquid suitable for the nature and use of medical devices, and both solvents should be compatible with the test system.
How to select typical products for testing blood concentrators?
The selection of typical products includes all raw materials and components, the most complex structure, the highest risk, and the performance that can cover other models of this registration unit, for full project registration testing. For products within the same registration unit, it is recommended to conduct full project testing on the model with the largest membrane area, and then test the physical performance of the model with the smallest membrane area. All components should undergo registration testing, especially those with special structures and performance. After completing the testing of typical products, differential testing can be conducted on other models within the same registration unit.
Can a product have two raw material suppliers?
The application materials need to specify the product's raw material suppliers. If there are two suppliers for the same raw material, the applicant must control the procurement of materials provided by each supplier separately (relevant application materials include quality agreements between raw material suppliers and product manufacturing companies, raw material quality control standards, raw material test reports, qualifications of raw material suppliers, etc.). Products made from raw materials from different sources must undergo separate performance verification/confirmation and risk assessment (including biocompatibility evaluation) to ensure that products made from two different sources of raw materials have consistent performance and meet safety and efficacy requirements. If necessary, the product manufacturing company also needs to conduct on-site audits of raw material suppliers.
How should the registration units of mandibular distractors be divided?
Mandibular distractors are mainly divided into upper jaw distractors and lower jaw distractors, which should be classified into different registration units. If the materials used in the product components (including material brands) are different, they should be classified into different registration units. If the materials of the product components are different but the products are assembled or used together as a whole, they can be declared under the same registration unit.
Requirements for environmental testing of in vitro diagnostic equipment
In vitro diagnostic equipment generally specifies its environmental conditions in the instructions or labels. Therefore, whether it's a domestic or imported product, when there are changes in the environmental conditions of in vitro diagnostic equipment applying for product registration or approved products, the relevant verification data for environmental testing must be submitted to demonstrate the safety and effectiveness of the declared product under its claimed environmental conditions. 1. If the declared product complies with applicable mandatory standards that reference GB/T 14710, environmental testing should be included as part of the product's technical requirements. Refer to the requirements of the mandatory standards without needing to detail each experimental condition; simply state that it should comply with the applicable chapters of GB/T 14710. The registration inspection report should include the content of the environmental testing. 2. If the declared product doesn't comply with applicable mandatory standards, one of the following documents can be submitted as verification data demonstrating that environmental conditions do not affect the safety and effectiveness of the product, and there is no need to reference GB/T 14710 in the product's technical requirements: (1) Registration inspection report including environmental testing. (2) Commissioned inspection report for environmental testing. (3) Research data showing that environmental conditions do not affect the safety and effectiveness of the product, including climate conditions (temperature, humidity), mechanical conditions (vibration, impact), transportation conditions, power adaptability, and other relevant factors.
There are various products on the market containing sodium hyaluronate, such as eye drops, face masks, and intra-articular injection solutions. Which of these products are considered medical devices?
According to the "Announcement on the Management Categories of Medical Sodium Hyaluronate Products" (CFDA Announcement No. 81 of 2009), medical sodium hyaluronate (hyaluronic acid sodium) products are categorized based on different clinical uses (indications) as follows: (1) Products with a defined pharmacological effect used to treat arthritis, dry eye syndrome, skin ulcers, etc., are managed as pharmaceuticals. (2) Products used for assisting ophthalmic surgery, preventing surgical adhesions, filling to increase tissue volume, etc., are managed as medical devices. Injectable modified sodium hyaluronate used in plastic surgery, intended to increase tissue volume, should be managed as Class III medical devices. For injectable cosmetic products used in plastic surgery that are not intended to increase tissue volume, their classification as medical devices depends on their specific ingredients and primary mechanisms of action. Companies must apply to the relevant authorities for the determination of the product's management category or attributes before declaring them.
How to determine the sample size in clinical trials of medical devices
The sample size for a trial is determined based on the main evaluation criteria of the trial. The clinical trial protocol should outline the relevant factors for determining the sample size and the specific calculation method for the sample size. Relevant factors for determining the sample size include the type of clinical trial design and comparison, the type and definition of the main evaluation criteria, the clinically meaningful threshold δ for the main evaluation criteria (if applicable), relevant parameters for the main evaluation criteria (such as expected efficacy rate, mean, standard deviation, etc.), Type I error rate α and Type II error rate β, as well as the expected dropout rate of subjects. The relevant parameters for the main evaluation criteria are estimated based on publicly available data or the results of exploratory trials. The clinical trial protocol should clearly specify the basis for these estimated values. For example, in the design of a non-inferiority trial for an aortic stent graft, it is generally recommended to set α at two-sided 0.05 and β not exceeding 0.20. You can refer to the "Guiding Principles for the Design of Clinical Trials of Medical Devices" for more details. For medical devices with specific sample size requirements outlined in the relevant guidance principles, it is important to consider meeting the corresponding requirements as per the guidance principles.
How should the registration unit for sternal plates be divided?
Sternal plates are used for sternal fixation after sternotomy or internal fixation of sternal fractures. If the constituent materials (including material grades) of the product are different, they should be classified into different registration units. If the constituent materials of the product components are different but are used as a whole assembly or in combination, they can be declared under the same registration unit. Accessories such as bone screws used in conjunction with sternal plates can be registered together with the sternal plate to form a sternal fixation system.
Can calibration and quality control materials be added to the reagent registration unit through a change application?
If an applicant wishes to add calibration and/or quality control materials to an in vitro diagnostic reagent registration unit that originally did not include them, they can apply for this through a change in licensing under the following conditions: they must provide evidence demonstrating that the added calibration and/or quality control materials were indeed intended for use with the reagent at the time of registration, these added materials match the original product's reaction system and testing processes, adding calibration and/or quality control materials does not alter the product's traceability and quality control methods, and the quality system at the time of registration should cover the intended additional calibration and quality control materials. Supporting evidence may include, but is not limited to: proof of using the intended calibration and quality control materials during product registration testing, evidence of quality system coverage, and documentation from the original registration that supports the above points. Otherwise, calibration and/or quality control materials cannot be added to the original registration unit through a change in licensing.
Can high-frequency electrodes with coated tips be classified in the same registration unit as those without coating?
According to the "Guiding Principles for the Division of Medical Device Registration Units" (Notice No. 187 of 2017) and with reference to the principles of registration unit division in the "Guiding Principles for the Registration Review of Surgical Electrodes" (Revised in 2017), high-frequency electrodes with coated tips can be considered the same registration unit as those without coating.