TX Q&A

The precision of quantitative in vitro diagnostic reagents is influenced by various factors such as operator, measurement instrument, measurement protocol, reagent lot, calibration (calibrator lot, calibration interval), run, time, location, and environmental conditions. Generally, it is not necessary to evaluate each influencing factor separately. A balanced nested design can be used to integrate these factors to design precision tests, thereby obtaining analytical results for repeatability, within-laboratory precision, between-laboratory precision, and lot-to-lot precision.

The length, width, thickness, hole diameter, number and distribution of holes, surface treatment methods, etc., of a metallic bone plate can all affect its bending performance. When setting acceptable limits for performance indicators, all these factors should be considered rather than just the thickness of the bone plate.

For changes in contraindications and other contents outside the items specified in the registration certificate and its annexes, the registrant can apply for changes by submitting an application to notify the change of the instructions for use.

The LOD and linearity studies for in vitro diagnostic reagents involve the establishment and validation of LOD and linearity. The samples used for establishing and validating the LOD should not be duplicated, and the samples during the study should cover all claimed types or major types. Applicants should submit registration information for all applicable instrument types, structural composition, instrument performance, reaction program settings, and a comparison of reaction systems. Representative instrument types and other types should have basic similarities in working principles, detection methods, reaction conditions, and signal processing. If there are representative instrument types within the applicable models for the product, applicants may choose to perform the establishment study on three batches of products and the validation study on one batch of products using the representative instrument type. They should also perform the validation study on three batches of products using other instrument types. Alternatively, applicants can choose to perform the establishment study on three batches of products and the validation study on one batch of products using all applicable instrument types. The analytical performance of all applicable instrument types should be essentially consistent. If any analytical performance for a particular test item differs across different instrument types, a thorough analytical performance establishment and validation study should be carried out specifically for those differences using the different instrument types. These are the general requirements for conventional in vitro diagnostic reagents. For new products, new methods, special products, or new issues that arise during performance evaluation, the specific situation should be analyzed based on the submitted documentation.

The generic name of medical devices should follow the "Guiding Principles for Naming Generic Names of Medical Devices" and the naming guidelines of various product classification catalogs. The GB 9706.1 standard provides clear definitions for "handheld equipment", "mobile equipment", "portable equipment", and "transportable equipment"; however, meeting these definitions does not automatically allow the inclusion of these descriptive terms in the product name. Characteristics that are inherently common to a type of product are generally not reflected in its generic name. For example, a surgical electrode is invariably handheld, so the term "handheld" would not be added to its name. Conversely, if a product type usually comes in various designs and it's necessary to distinguish between these designs, then descriptive terms might be added. For instance, a "portable ultrasound diagnostic device" typically supports prolonged internal battery operation and is easy to hold and carry, suitable for switching between different usage scenarios like outpatient clinics, wards, operating rooms, and emergency situations. On the other hand, an ultrasound diagnostic device without any descriptive term typically refers to a cart-based mobile system, which usually does not involve changes in usage scenarios but simply moves between different locations (e.g., from one exam room to another). Therefore, descriptive terms are only considered in the product name when the product design significantly deviates from the norm and excluding such terms would cause ambiguity. For example, ultrasound surgical devices typically consist of a console (tabletop equipment), a transducer, and a handpiece. If a product integrates the power source, control components, transducer, and handpiece into a single handheld unit, it could be named "handheld ultrasound surgical device."

According to GB 27949-2020 "General Requirements for Disinfectants for Medical Devices", the shelf life of a properly packaged product should be no less than 12 months. The test items should refer to the relevant clauses in the technical requirements, such as the content of each main active ingredient (the content decline after storage should be ≤10%, and the content of the main active ingredients after storage should not be lower than the lower limit specified in the product technical requirements), microbial killing indicators, appearance (including whether there are color changes, precipitation or the formation of suspensions), fill volume, pH value, corrosion resistance, etc.

In the registration application materials, the description of blue light blocking performance should avoid using promotional language such as "reducing radiation hazards." Instead, it is recommended to describe the performance indicators in accordance with the product technical requirements and research data, using terms like "blue light radiation reduction rate" and "UV light radiation reduction rate."

If the raw materials for orthopedic or dental implant products come from two suppliers, the applicant needs to evaluate the suppliers according to the requirements of the quality management system. In the registration application materials, the product raw material suppliers must be clearly identified. If the same raw material is sourced from two different suppliers and it is not possible to confirm that the components, content, and synthesis methods used by the two manufacturers are identical, the provided documentation must include performance verification/validation and risk assessment (including biological evaluation) for the products made from raw materials of different sources. This ensures that the products made from the raw materials from both sources have consistent performance and meet safety and effectiveness requirements.

For bone implant products, if the applicant directly purchases the designed and finalized products without any further processing, only performing subsequent steps like repackaging, sterilization, and packaging, the applicant can apply for registration as the certificate holder. The applicant needs to incorporate the quality control of the products provided by the supplier into their own quality control system. Additionally, when submitting the registration application, the applicant must provide the necessary registration documents for the application product according to current regulations and normative documents, such as performance research data, biological evaluation data, product technical requirements, inspection reports, and clinical evaluation data.

For medical devices that provide energy or substance therapy to patients, it is usually necessary to provide research data on the dose-response relationship and energy safety. This data should demonstrate the safety, effectiveness, and rationality of the treatment parameter settings, reflect the effects and relationships between energy and tissues, and confirm that the energy does not cause unacceptable harm to normal tissues beyond the intended target tissues. The dose-response relationship and energy safety research should include data analysis and summary from one or more non-clinical trials (bench tests, ex vivo tissue tests, in vivo animal tests), clinical trials, etc., of the product being submitted. The dose-response relationship study should evaluate the correlation between different energy output levels (covering all performance parameters and adjustment ranges of the product) and clinical application effects (including various indications or types of tissues) under all working modes and output methods of the product being submitted. These data can also serve as the basis for determining performance parameters and support materials for indications. The dose-response relationship study can be conducted through laboratory simulated tissues, ex vivo tissues, and/or in vivo animal tests, with clinical trial data and clinical experience data also being part of it. Energy safety studies should evaluate whether the energy, when acting on the target tissue under all working modes and output methods, causes unacceptable harm to the surrounding normal tissues. For the same indications and application sites, the maximum output energy level can usually be analyzed to represent other levels. Energy safety studies can be conducted through tissue and/or animal tests, analyzing the morphological and pathological changes in tissues before and after the treatment to determine if unacceptable energy damage has occurred. It's important to note that the related studies mentioned above should be conducted based on the product itself to demonstrate its energy characteristics. When conducting these studies, establishing a control group and performing equivalence analysis with already marketed products can also be considered to confirm that the dose-response relationship and energy safety are acceptable.