Clinical research requirements for dressing products

With the rapid development of dressing technology, dressing companies are increasingly consulting on the registration of related products. In response to these needs, CIRS summarized and analyzed the basic clinical requirements and frequently asked questions of such products, and provided relevant personnel with reference for clinical research and Clinical Study Report preparation of dressing products.

Part 1: the routes of dressing product clinical evaluation

Presently, there are three main types of clinical data submission routes for dressing products clinical evaluation:

◆  Products that are exempted from clinical trials

Ÿ   According to the Class III medical device clinical trial exemption catalogue, polyurethane foam dressings, alginate dressings, alginate filling strips, hydrocolloid dressings, hydrophilic fiber dressings, hydrocolloid oil yarns, etc. can be exempted from clinical trials. 

Ÿ   In the clinical part of the product registration application, you can submit the following information:

1.       Information on the comparison between the dressing products to be registered and the related contents of the Class III medical devices clinical trial exemption catalogue.

2.       Information on the comparison of dressing products to be registered with similar Class III medical devices that have been approved for NMPA.

Ÿ   However, the exemption does not include the following:

1.         Products that claim to promote epithelialization, guide tissue regeneration, promote wound healing, reduce pain, stop bleeding, reduce scarring, and prevent adhesion.

2.         Declared products that can be used for wounds in the body, third-degree burns, wounds infected, wounds with more necrotic tissue, and patients with wound sepsis.

3.         Products containing active ingredients: such as pharmaceutical/medicinal active ingredients, biological products/bioactive ingredients, silver, disinfectants, etc.

4.         Other new products.

◆  Clinical evaluation of the same type of products

Ÿ   For dressings that do not meet the exemption conditions, the clinical data of the same variety of products can be compared, analyzed and evaluated according to the “Guidelines for Clinical Evaluation of Medical Devices” under the premise of meeting the requirements of the registration regulations.

◆  Conduct clinical trial research

Ÿ   For dressing products that do not meet the exemption conditions and cannot be compared to the same variety of products, clinical trial can be conducted. The clinical trial shall comply with the requirements of relevant documents such as the Quality Management Practice for Clinical Devices Clinical Trials.

Part 2: the basic requirements of dressing clinical trials

Before conducting clinical trials of dressing products, the company needs to clarify the clinical mechanism of action of the dressing, the expected effect on the wound, the possible risks and possible adverse events. Moreover, the company needs to fully consider the claimed effects of its products when conducting clinical trials. The basic requirements for dressing clinical trials include, at least, the following:

◆  Clinical trial purpose and type

Ÿ   The purpose of the clinical trial is to scientifically verify whether the dressing applied for registration is safe and effective.

Ÿ   Randomized, controlled or prospective clinical study is recommended.

◆  Research subject

Ÿ   The clinical trial study subject selection depends on the type and extent of the wound that the product is intended to use.

Ÿ   It is necessary to identify contraindicated population in the clinical application, such as patients who are allergic to the ingredients contained in the dressing. 

◆  Control group selection

Ÿ   It is recommended to select a product that has been registered and has sufficient evidence to prove its effectiveness as a control group for clinical study. It is also necessary to explain the basis for selecting this product as a control group. The same treatment and care should be used in both the control and clinical groups.

◆  Evaluation index

Ÿ   The intended use of the dressing usually has two categories: improved wound healing and improved wound care. The company shall select the appropriate evaluation indicators based on the intended use of the product.

Ÿ   For products that claim to have a certain function, such as promoting epithelialization, guiding tissue regeneration, promoting wound healing, relieving pain, stopping bleeding, reducing scarring, anti-adhesion, etc., the clinical group and the control group should be compared in terms of clinical statistics difference.

◆  Evaluation and quantification of clinical endpoints

Ÿ   For clinical trials, the method of assessing the clinical endpoint should be predetermined and consistent throughout the clinical trial. The time to determine the clinical endpoint should be determined based on the developmental characteristics of the applied wound and product claims.

Ÿ   The wounds need to be measured regularly during clinical trials. The evaluating system of the wound is the basis for determining the effectiveness of the study. Clinical trials can use a widely accepted evaluating system in the medical field.


Part 3: Dressing clinical trials Q&A

◆  How to choose the outcome measures of clinical trials?

Ÿ   The appropriate outcome measures of the clinical trial should be selected according to the specific wound condition. It is generally the choice of the complete closure of the wound as the outcome measure, but since some dressings may not be used for the entire process of wound healing, the time point at which the wound is not fully closed may also be selected as the outcome measure. In clinical trials, it is necessary to record the wound closure rate, observe the wound healing rate, explain the basis of each observation time point and outcome measure selection, and evaluate the effect of the dressing on the entire wound healing process.

◆  How to determine the evaluation index of clinical trials

The evaluation indexes should include no less than the effectiveness indexes and safety indexes, and there should be measures for the treatment and prevention of adverse events.

Ÿ   Effectiveness evaluation indicators (Not limited to the following indexes):

1.       Main effectiveness evaluation index: wound closure rate.

2.       Secondary effectiveness evaluation indexes: such as the incidence of wound infection, pain level, exudation, body fluid loss, bleeding, whether the product is convenient to use, whether the product adheres to the wound, etc.

Ÿ   Safety evaluation indicators (Not limited to the following indexes):

1.       Systemic/local reaction and safety.

2.       Laboratory safety Inspection index.

Ÿ   How to choose a wound evaluation method

The methodology for assessing and quantifying wound characteristics is currently in the process of development. Regardless of the method used, it is recommended to consider the following factors:

1.       Classification of wounds

2.       The size of the wound

3.       Wound image recording

4.       Infection


China Medical Device Regulation Related Resources provided by CIRS:

Ÿ   China NMPA Medical Device Filing and Registration

Ÿ   Medical Device Clinical Trial Consulting

Ÿ   Medical Device GMP/GSP/GCP Compliance Consulting

Ÿ   Medical Device GCP Compliance Audits

Ÿ   China Medical Device Regulation Training

Ÿ   Strategic and Regulatory Consulting for Medical Device Registration in China

Ÿ   Guideline: Medical Device Registration in China

Ÿ   Annual Report: Medical Device Market in China

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