Report ID: YN-CXQ-CR01

Version number and date: V2.0, 20250403

Prospective, multicenter, randomized, parallel-controlled, superiority clinical trial report on the safety and efficacy of single-use gel patch formers for clinical use

Name of the test medical device: Disposable gel patch former

Model specification used in clinical trials: YN-PAT 35

Class III medical devices subject to clinical trial approval: Yes No 

Clinical trial team leader unit: Run Shaw Hospital Affiliated to Zhejiang University School of Medicine

Coordinating Investigator: Wang Qiang

Clinical trial start time: October 10, 2024

End time of clinical trial (last subject out of the group): January 12, 2025

Scheme number: YNCXQ-20240820

Solution version number and date: V4.0, March 17, 2025

Sponsor: Hangzhou Yuannang Biotechnology Co., Ltd

Where the original materials are stored:

Run Shaw Hospital Affiliated to Zhejiang University School of Medicine

Ningbo Sixth Hospital

Fill in the instructions

1. The sponsor and principal investigator shall conduct clinical trials in strict accordance with the clinical trial plan in a serious and responsible manner, and complete the clinical trial report fairly and objectively.

2. The sponsor and principal investigator shall be responsible for the authenticity and scientific nature of the test report.

3. This report shall be signed and dated by the principal investigator, and submitted to the sponsor after being reviewed and signed by the medical device clinical trial institution. The multicenter clinical trial report shall be signed and dated by the coordinating investigator, and submitted to the sponsor after being reviewed and signed by the medical device clinical trial institution of the team leader unit.

4. The report should have a table of contents.

5. Abbreviations, references, etc. can be added according to the needs of the report.

Table of contents

1. Report Summary 1

2. Background of clinical trials 4

3. Purpose of clinical trial 5

4. Implementation of clinical trials6

4.1. Test flow diagram 6

4.2. Subject Selection 9

4.3. Clinical trial sample size 10

4.4. Test medical devices 10

4.5. Clinical evaluation criteria 11

5. Statistical analysis methods 16

5.1. Analyze datasets 16

5.2. Subject Exclusion Criteria 16

5.3. Statistical analysis methods 17

5.4. Handling of missing and outlier values 17

6. Clinical trial results 19

6.1. Analyze the dataset 19

6.2. Demographic data and baseline characteristic analysis 20

6.3. Effectiveness evaluation index 23

6.4. Safety evaluation 26

6.5. Adverse events and their treatment 30

6.6. Defects in instruments 31

7. Analysis and discussion of clinical trial results and their indications, contraindications and precautions, etc.32

7.1. Analysis and discussion of clinical trial results 32

7.2. Indications 34

7.3. Contraindications 34

7.4. Precautions 35

8. Clinical trial conclusions 35

9. Existing problems and suggestions for improvement 35

10. Multicenter clinical trials All clinical trial institutions 36

11. List of test personnel 36

12. Explanation of ethical situations 37

13. Other circumstances that need to be explained 38

13.1. Description of the revision of the plan 38

13.2. Deviation of the test protocol 39

14. Coordinate the signature of the researcher, indicate the date, and the review signature of the clinical trial institution 40

Report Summary

A total of 41 subjects were screened in this clinical trial, 1 case failed screening, 2 cases withdrew from the screening period, and finally 38 cases were successfully enrolled and included in the full analysis set ( FAS), including 19 in the experimental group and 19 in the control group. 38 cases met the protocol set (PPS), including 19 cases in the experimental group and 19 cases in the control group. Thirty-seven cases were included in the safety analysis set (SS), including 18 cases in the experimental group and 19 cases in the control group, all of which met the statistical requirements of at least 18 cases in the experimental group and the control group. The total number of cases was 36. In addition, the blood of all subjects was divided into two groups (patch group and PRP group) for pairing experiments under the premise that the three indicators of growth factor concentration, ultimate tensile intensity and platelet concentration were in accordance with the protocol set, so the sample size of each group was 38 Example.

Demographic data

Demographic indicators include age, gender, height, and weight, and are analyzed using the full analysis set (FAS), and the results are as follows:

The average age of the experimental group was (57.95±12.08) years old and that of the control group was (61.63±7.05) years, and the difference between the groups was not statistically significant (P>0.05).

Gender, 18 males in the experimental group, accounting for 94.74%, and 1 female, accounting for 5.26%. In the control group, there were 13 males, accounting for 68.42% and 6 females, accounting for 31.58%, and the differences between groups were statistically significant (P<0.05）。

The average height of the experimental group was (169.38±7.23) cm, and the average height of the control group was (168.01±8.38) cm, and the difference between the groups was not statistically significant (P>0.05). ）。

The mean weight was (68.41±11.99) kg, and the mean weight of the control group was (64.42±9.96) kg, and the difference between the groups was not statistically significant (P>0.05）。

Past history

The anamnesis includes past medical history and medication history, which were analyzed using the full analysis set (FAS), and the results are as follows:

In the experimental group, there were 19 subjects with past medical history, accounting for 100%, and 0 subjects with no past medical history, accounting for 0%. In the control group, there were 19 subjects with a history of medical history, accounting for 100.00%, and 0 subjects with no past medical history, accounting for 0%. There was no significant difference between groups (P>0.05).

Medication history, 19 subjects in the experimental group had a history of medication, accounting for 100%, and 0 subjects had no history of medication, accounting for 0%. In the control group, there were 19 subjects with a history of medication, accounting for 100.00%, and 0 subjects with no history of medication, accounting for 0%, There was no significant difference between groups (P>0.05).

Allergy history, 2 subjects in the experimental group had a history of allergy, accounting for 10.53%, and 17 subjects had no history of medication, accounting for 89.47%. In the control group, there was 1 subject with a history of medication, accounting for 5.26%, and 18 subjects with no history of medication, accounting for 94.74%. There was no significant difference between groups (P>0.05).

Wound size

The results of FAS-based analysis showed that there were 11 subjects in the experimental group with small and superficial wound size, accounting for 61.11%, and exposed joints or bones6 cases, accounting for 33.33%, and 1 case with extensive, deep and involving surrounding tissues, accounting for 5.56%. In the control group, 10 subjects with small and superficial wound size, accounting for 55.56%, and 2 subjects with exposed joints or bonescases, accounting for 11.11%, and 6 subjects with extensive, deep and involving surrounding tissues, accounting for 33.33%; There was no significant difference between groups (P>0.05).

Debridement assessment score

The results of FAS-based analysis showed that the debridement assessment score of the experimental group was 1 2.58±0.96 points. The debridement assessment score of the control group was 12.58±0.96 points. There was no significant difference between groups (P>0.05).

Study device use

In the full analysis set (FAS), the experimental group used a single-use gel patch former, model: YN-PAT 35, a total of 19 cases (accounting for 100.00%). A total of 19 cases (100.00%) of platelet-rich plasma gels were prepared by secondary centrifugation in the control group.

Effectiveness evaluation indicators

The main evaluation index was the qualified rate of platelet concentration.

In the full analysis set (FAS), a total of 12 platelet concentrations in the experimental group met the set threshold, and 7 cases did not, and the platelet concentration was qualified 63.16%； In the control group, 2 platelet concentrations met the set threshold, 17 cases did not, and the platelet concentration pass rate was 10.53%. The difference between the groups was statistically significant (P<0.05). The difference in the qualified rate of platelet concentration between the two groups was 52.63% (95%CI: 22.02%~73.22%) The lower limit of the 95% CI confidence interval was 22.02%, which was 10% higher than the superiority cut-off, inferring that the effectiveness of the experimental group was better than that of the control group.

In the protocol set (PPS), a total of 12 platelet concentrations in the experimental group met the set threshold, and 7 did not, the platelet concentration pass rate was 63.16%; In the control group, 2 platelet concentrations met the set threshold, 17 cases did not, and the platelet concentration pass rate was 10.53%. The difference between the groups was statistically significant (P<0.05). The difference in the qualified rate of platelet concentration between the two groups was 52.63% (95%CI: 22.02%~73.22%) The lower limit of the 95% CI confidence interval was 22.02%, which was 10% higher than the superiority cut-off, inferring that the effectiveness of the experimental group was better than that of the control group. The conclusions of conformity with the protocol set (PPS) were consistent with the full analysis set (FAS).

In summary, it can be confirmed that the effectiveness of the experimental group is better than that of the control group.

The secondary evaluation indicators were the bacterial condition of the wound, the concentration of growth factors, the ultimate tensile strength, the postoperative wound, the performance of the product, and the platelet concentration in the three days after the operation, and the specific statistical analysis results were as follows:

Wound bacteria at three days after surgery: In the full analysis set (FAS), the bacterial status score of the wound in the experimental group was (0.833±0.514, and the score of wound bacteria in the control group was (0.667±0.594 at three days after surgery), and the difference between the groups was not statistically significant (P% 3E0.05）。 In the conformity set (PPS), the bacterial score of the wound in the experimental group was (0.833±0.514 at three days after surgery, and the score of bacterial status in the wound at three days after operation in the control group was (0.667±0.594), and the difference between the groups was not statistically significant ( P>0.05。

Growth factor concentration: Based on the conformity to protocol set (PPS), the concentration of growth factor PDGF-BB in the patch group extract was (5.89±4.35) pg/mL, PRP The concentration of growth factor PDGF-BB in the extract was (7.13±5.16) pg/mL, and the difference between the groups was not statistically significant (P>0.05). ）。 The concentration of growth factor TGF-β1 in the patch group was (2.52±2.42) ng/mL, and the growth factor TGF-β1 in the PRP group was in the extractThe concentration was (2.49±2.50) ng/mL, and the difference between groups was not statistically significant (P>0.05). The concentration of growth factor IL-1β in the patch group was (2.62±6.88) pg/mL, and the growth factor IL-1β in the PRP group was (2.626.88) pg/mL The concentration was (3.26±7.85) pg/mL, and the difference between the groups was not statistically significant (P>0.05).

Ultimate tensile strength: Based on the conformity scheme set (PPS), the ultimate tensile strength of the patch group was (0.711±0.141, and the ultimate tensile strength of the PRP group was (0.393±0.106) N, the ultimate tensile strength of the patch group was significantly higher than that of the PRP group (P<0.05).

Postoperative wound status: In the full analysis set (FAS), the wound condition score of the experimental group at 3 days after operation was (0.21±0.42) points, and the control group was controlled The wound status score at 3 days after surgery was (0.28±0.46), and the difference between the groups was not statistically significant (P>0.05). ）。 In the protocol set (PPS), the wound condition score was (0.21±0.42) in the experimental group and (0.210.42) after surgery The score of the wound situation at 3 days was (0.28±0.46), and the difference between groups was not statistically significant (P>0.05).

Product use performance: In the full analysis set (FAS), a total of 19 cases in the experimental group were satisfied with the product use performance evaluation and 0 cases were dissatisfied, and the product use performance satisfaction rate was 100.00%. In the PPS protocol set, 19 cases in the experimental group were satisfied with the performance of the product, 0 cases were dissatisfied, and the satisfaction rate of the product performance was 100.00%。

Platelet concentration: Based on the conformity to protocol set (PPS), the platelet concentration in the patch group was (458±285) ×10⁹/L, and the platelet concentration in the PRP group was ( 253±181)×10⁹/L, and the platelet concentration in the patch group was significantly higher than that in the PRP group (P<0.05）。

Based on the above analysis, compared with the control group, the platelet gel patch prepared by the experimental device was better than the platelet-rich plasma gel, and the effectiveness met the clinical needs.

Safety evaluation indicators

Laboratory abnormalities: In the safety analysis set (SS), there was no significant difference in the incidence of blood routine abnormalities in the experimental group and the control group at 3 days after surgery (P>0.05). There was no significant difference in the incidence of abnormal liver function at 3 days after operation between the experimental group and the control group (P>0.05). There was no significant difference between the incidence of abnormal renal function at 3 days after operation between the experimental group and the control group (P>0.05). There was no significant difference in the incidence of C-reactive protein abnormalities between the experimental group and the control group at 3 days after operation (P>0.05).

Vital signs: In the safety analysis set (SS), the systolic blood pressure of the experimental group and the control group was 117.74±11.9 mmHg, respectively123.50±15.14 mmHg, and the difference between groups was not statistically significant (P>0.05). The diastolic blood pressure of the experimental group and the control group were 74.16±8.27 mmHg and 73.50±9.58 mmHg, respectively, and the difference between the groups was not statistically significant (P>0.05). ）； The respirations of the experimental group and the control group were 18.21±1.47 breaths/min and 18.00±1.08 breaths/min, respectively, and the comparison between the groups was not statistically significant (P>0.05）； The pulses of the experimental group and the control group were 73.26±8.10 beats/min and 73.22±6.91 beats/min, respectively, and the comparison between the groups was not statistically significant (P>0.05）； The body temperatures of the experimental group and the control group were 36.59±0.24 °C and 36.58±0.27 °C, respectively, and the difference between the groups was not statistically significant (P>0.05).。

Occurrence of adverse events and serious adverse events: In the safety analysis set (SS), a total of 6 subjects in the experimental group had adverse events, with an incidence rate of 31.58%. A total of 8 subjects in the control group had adverse events, with an incidence rate of 44.44%, and the difference between groups was not statistically significant (P>0.05). In this clinical trial, there were no device-related adverse events, no serious adverse events, and no device-related serious adverse events.

Based on the above analysis, it can be confirmed that the disposable gel patch molder entrusted by Hangzhou Yuansang Biotechnology Co., Ltd. to Zhejiang Disai Biotechnology Co., Ltd. is safe in clinical application and meets clinical needs.

Background of the clinical trial

Enhancing wound tissue healing has been the goal of doctors for thousands of years. As China accelerates into an aging society, the trauma care market is growing rapidly. Many patients, especially the elderly with underlying diseases, are not repaired in time after injury, and are prone to develop into chronic wounds and face risks such as gangrene and amputation. Treatment of refractory wounds is an ongoing medical problem, with tens of millions of patients suffering from refractory wounds in China. Taking diabetic foot ulcer (DFU) as an example, its treatment cost accounts for 25-50% of the total cost of diabetes treatment. Among them, 5%-8% of DFU patients require amputation in the first year, and about 45%-55% of patients die 5 years after amputation. Refractory wounds have become a health problem with a large base of patients and urgently need to be solved.

At present, the treatment methods of refractory wounds mainly include necrotic tissue debridement, infection control, revascularization, local decompression and comorbidity treatment. However, these treatment strategies often need to be performed simultaneously and lead to significant treatment costs and complexities. In order to improve the healing of intractable wound tissue, some international companies have developed many types of new technologies and regenerative dressing products, including growth factor delivery, gene therapy, etc. However, due to the complexity of refractory wounds, different individuals have different biochemical characteristics, and it is difficult to achieve ideal wound healing by supplementing a single growth factor or targeting only a single gene, and some advanced treatments have unknown risks. Therefore, these treatments have not been officially approved in China. As a regenerative repair treatment, autologous PRP has been widely used in postoperative repair of fractures in China. There are a large number of clinical studies at home and abroad that confirm that autologous PRP can effectively promote wound healing. As a convenient, painless, low-risk treatment method, rich in a large number of growth factors, the therapeutic effect is remarkable, and autologous PRP treatment is widely accepted by patients.

Although the wound healing effect is excellent, due to the diversity of clinical tissue wounds, there are no PRP products on the market that are well adapted to wound repair, so domestic autologous PRP/PRP gel is not widely used in wound treatment. Most of the PRP products currently on the market are finally made of PRP liquid, which cannot be directly applied to the treatment of tissue repair such as refractory wounds. Some products combine thrombin to make fibrinogen aggregate in PRP plasma to form PRP gels. However, naturally formed PRP gels have a loose structure and extremely high water content. There are many adverse consequences when used directly on the wound: a) Naturally formed PRP gel has a very high water content, after gauze bandaging, the water in the gel will be gradually absorbed by the gauze, and the gel will immediately shrink after water loss, which will cause a large loss of growth factors and cause gauze exudation, increasing the risk of further infection of the wound. b) Naturally formed PRP gels have a loose structure and are easily degraded. Moreover, the surface of the gel is moist and smooth, making it difficult to continue to adhere to the wound, and it is very easy to cause the gel to shift due to the patient's movement. c) From the microstructure, it is found that the pore size of the naturally formed PRP gel is larger than that of leukocytes and platelets (>9μm), so it cannot effectively realize the encapsulation of leukocytes and platelets, and is easy to be quickly lost and degraded under the washing of body fluids. It cannot play a role in promoting continuous repair. Therefore, there are still many inconveniences and problems in the treatment of refractory wounds. Therefore, there is an urgent need for a product that can improve the application of PRP in difficult-to-heal wounds to achieve a good therapeutic effect of PRP in accelerating wound tissue healing.

In view of the inconvenience of most PRP preparation products on the market for the use of difficult-to-heal wounds, the research team of Hangzhou Yuancapsu Biotechnology Co., Ltd. has developed a molder product that can prepare PRP into concentrated PRP gel patches. As a former, the product prepares loose plasma gels into higher-strength plasma gel patches without changing the chemical structure and biological properties of PRP gels through physical extrusion. The product is simple to operate and has a short preparation time. Compared with the naturally formed PRP gel, the gel patch has stronger mechanical strength, and can be sutured with sutures with wound tissue, and can be cut at will according to the shape of the wound. The formed gel patch significantly prolonged the degradation time of the gel and increased the slow-release concentration and duration of growth factors. At present, this product has been inspected by the National Medical Products Administration (NMPA) certified inspection agency and concluded to be qualified, and has applied for clinical trials in order to further evaluate the clinical safety, efficacy and operability of the device.

Clinical trial objectives

The purpose of this study is to verify the safety and efficacy of the clinical operation of the research single-use gel patch former commissioned by Hangzhou Yuancapsu Biotechnology Co., Ltd. and produced by Zhejiang Disai Biotechnology Co., Ltd.

Implementation of clinical trials

Test flow chart

Case enrollment

Sign the informed consent form (signature and date), and record the subject's basic information, including date of birth, gender, height, weight, clinical diagnosis and past medical history, allergy history, etc. Record the results of the examination that need to be performed before enrollment. Appropriate subjects are selected according to the inclusion and exclusion criteria.

Inspection/Inspection Items

Visit 1: Screening period examination

Preoperative liver function tests: alanine aminotransferase (ALT), aspartate aminotransferase (AST).

Preoperative renal function tests: creatinine (CRE), urea nitrogen (BUN), or urea (UREA).

Preoperative blood routine examination: red blood cell count (RBC), white blood cell count (WBC), neutrophil ratio (NEUT%), lymphocyte ratio (LTMPH%), hemoglobin concentration (HGB). ), platelet count (PLT).

Preoperative C-reactive protein test.

Vital signs (temperature, pulse, respiration, blood pressure).

Visit 2: Chronic ulcer repair

Preoperative peripheral blood draw.

Bacterial culture of wound secretions after debridement.

Evaluation of product use performance after surgery.

Visit 3 (within 3 days after surgery):

Bacterial culture of wound secretions.

Blood routine tests: red blood cell count (RBC), white blood cell count (WBC), neutrophil ratio (NEUT%), lymphocyte ratio (LTMPH%), hemoglobin concentration (HGB). ), platelet count (PLT).

Liver function tests: alanine aminotransferase (ALT), aspartate aminotransferase (AST).

Renal function tests: creatinine (CRE), urea nitrogen (BUN), or urea (UREA).

Postoperative C-reactive protein examination.

Wound assessment.

Vital signs (temperature, pulse, respiration, blood pressure).

Confirm the group

This trial identifies the trial group of subjects according to the principle of randomization.

After the subjects sign the informed consent form, they will be given a screening number first, and the subject number will be given after passing the screening.

The screening number is composed of S+2-digit test center number + 2-digit serial number, and the screening number is given according to the time of signing the informed consent form, and if the serial number is less than 2 digits, 0 is added forward to make up for 2 digits.

Programmed with statistical software, stratified by center, given block length, subjects were divided into experimental and control groups in a 1:1 ratio, resulting in a randomization arrangement of at least 38 subjects, and a corresponding random number table was developed.

The subject number is a four-digit number composed of the center number and the serial number, the first 2 digits are the test center number, the last 2 digits are the serial number, and if the serial number is less than 2 digits, 0 is added forward to make up for 2 digits. After the subjects are selected, the investigator confirms the subject group according to the random envelope and takes the corresponding group of devices for treatment.

Procedure of operation of the test instrument

On the day of surgery, about 50-60mL of peripheral blood was drawn from the patient's vein, and 60mL was collected as much as possible.

About 20mL of peripheral blood were taken, and the control group was centrifuged at 150×g to obtain the upper layer of plasma and platelets, which were transferred to a new centrifuge tube for another 800 ×g centrifugation, discard 3/4 of the supernatant, and mix the lower layer to obtain platelet-rich plasma. The test group performed the same first step of centrifugation to obtain platelet-containing plasma for backup. After preparation, store at 1-10°C and send to the operating room as needed. The remaining blood is used to measure platelet concentration, tension, and growth factor concentration.

The wound site is disinfected according to the requirements of routine surgery, the necrotic tissue is fully removed, and the debridement is thorough until the soft tissue with healthy bleeding is completely exposed. According to the literature report, we designed an evaluation form for debridement treatment (Table 4 "Debridement Evaluation Form"), according to which the researcher scored according to the table, and when the scores of all three dimensions ≥ 4 points, and the total score ≥ 12 points, the debridement can be considered complete, and the secretion from the wound surface can be sent for bacterial culture testing.

References:

Schultz, G., et al. Wound Bed Preparation: A Systematic Approach to Wound Management. Wounds International, 2003. Mar; 11 Suppl 1:S1-28.

Falanga, V. Wound Healing and Its Impairment in the Diabetic Foot. The Lancet, 2005. Nov 12; 366(9498):1736-43.

Armstrong, D.G., et al. Debridement: The Key to Wound Healing. Podiatry Management, 2000. Dec; 6(4):627-60.

Wolcott, R.D., et al. "Biofilms and Chronic Wound Inflammation." Journal of Wound Care, 2008. Aug; 17(8):333-41.

The control group added thrombin in platelet-rich plasma at a volume of 1:10 and left for 3 minutes to form a gel. The control group used sterile forceps to gently pick up the gel and apply it to the wound.

The experimental group injected plasma and thrombin into the molding device according to the instrument operation manual, squeezed to form a gel patch, and gently picked up the gel with sterile forceps and applied it to the wound.

If there is a special need for surgery, the gel patch can be cut appropriately under sterile conditions, and the patch can be sutured and fixed with the soft tissue as needed.

The wound is sutured and covered with a dressing according to the requirements of the routine operation.

Subject selection

Selection criteria

Subjects eligible for this trial must meet all of the following criteria:

18-75 years old;

Patients with chronic wounds requiring debridement repair;

Wound duration> 4 weeks;

Volunteer to participate in this study and sign the informed consent form;

Exclusion Criteria  

Subjects should not participate in the trial if any of the following conditions occur:

Patients with severe thrombocytopenia and sepsis;

Patients who are allergic to rubber ingredients;

Patients who have been injected with glucocorticoids within 1 month or systemic corticosteroid therapy within 2 weeks;

Patients with malignant tumors;

Hemoglobin < 100g/L, platelet count < 100×10⁹/L ；

Mental illness, cognitive impairment, critically ill patients, minors, and pregnant women;

Those who have participated in or are participating in drug clinical trials within 3 months, or have participated in or are participating in other medical device clinical trials within 30 days;

Other conditions that the investigator deems unsuitable for participation in the study.

Subject withdrawal criteria

Subjects withdraw on their own

Regardless of the reason, the subject is unwilling or unable to continue the clinical trial, and the clinical trial is terminated by requesting the investigator to withdraw from the clinical trial;

Although the subjects did not explicitly propose to withdraw from the clinical trial, they no longer received treatment and examination and were lost to follow-up.

The researcher decided to withdraw

Subjects with allergic reactions or serious adverse events (SAEs) and unable to complete subsequent trials, the clinical trial should be terminated according to the investigator's judgment;

During the clinical trial, the subject has other complications and is not suitable to continue to undergo the clinical trial;

Subjects who do not meet the inclusion criteria of the trial, are wrongly selected due to meeting the exclusion criteria, and do not use the test device;

During the clinical trial, the subject has serious protocol deviations, such as using devices other than those specified in this protocol during the trial, or using drugs not within the specified range in the middle of the trial, so that the clinical trial results cannot be effectively evaluated;

Poor subject compliance.

After the termination of the subject's trial, the investigator should continue to provide appropriate treatment to the subject from the perspective of protecting the rights and interests of the subject, and inform the subject in detail of the treatment and related treatment received during the trial. Data from subjects can still be used to evaluate the safety of the product. The investigator should promptly feedback the termination of the subject's trial to the sponsor.

Clinical trial sample size

The main evaluation index of this trial was that the platelet concentration in platelet gel patches prepared by a disposable gel patch molder was better than that in platelet-rich plasma prepared under the same conditions. Therefore, this trial is based on the formula:

where α=0.05, β=0.2. PC and PT set thresholds for the platelet concentration symbols of the control group and the test group, which were PC and PT The absolute value of the difference is ∆ the efficiency threshold, and the positive value is taken.

According to the clinical situation, PC is 15%, PT is 65%, ∆=0.1.

The substitution formula yields , N=36.

According to statistical requirements, a total of 36 qualified cases were selected for this clinical trial to be statistically significant. According to the 5% dropout rate, 38 cases need to be selected in the end.

Experiment with medical devices

Experimental group

Peripheral blood was collected, and after debridement, PRP gel patches prepared by a disposable gel patch former were applied to the wound surface. Remaining blood is used for performance testing of PRP gels and gel patches.

Control group

Peripheral blood was collected, and after debridement, PRP gel was applied to the wound surface. Remaining blood is used for performance testing of PRP gels and gel patches.

Clinical evaluation criteria

Effectiveness evaluation

Main evaluation indicators

The main evaluation index was the qualified rate of platelet concentration.

Evaluation methods: Platelet concentrations in PRP and gel patches prepared by the product were tested.

Anticoagulant peripheral blood (about 20mL, evenly divided into platelet-rich plasma (PRP) group and gel patch (patch) group) was collected, and the PRP group was 150 ×g centrifugation 1 0 min to obtain the upper layer of plasma and platelets, transfer 10 mL of platelet-containing plasma to a new centrifuge tube, and centrifuge again at 800×g For 5 minutes, discard about 3/4 of the supernatant, mix the lower layer well to obtain platelet-rich plasma, and measure the platelet concentration as .

The upper layer of plasma and platelets were obtained after centrifugation of 150×g for 10 minutes, and the platelet plasma volume and platelet concentration were measured. According to the product manual, platelet plasma and 1/10 volume of thrombin are mixed in a disposable gel patch former and then extruded into a gel patch. The leachate liquid was retained, and the volume of the leachate fluid and platelet concentration were measured.

Platelet concentrations in each group were measured and calculated according to the formula.

Recording time: within 3 hours after the preparation of PRP gel patches.

Analysis method: Prepare the sample according to the evaluation method and measure it, and calculate the platelet concentration in the gel patch according to the following formula.

According to the blood routine platelet concentration of the patient V1 visit, the enrichment factor N of platelets in the control group and the test group was calculated according to the following formula:

Control group: Experimental group:

If the enrichment multiple is in the range of 2-8 times, it is considered qualified.

The pass rate of platelet concentration in the two groups was calculated and the superiority test was performed

Secondary evaluation indicators

Secondary evaluation indicator 1: Wound bacteria 3 days after surgery.

Evaluation methods: At the end of intraoperative debridement and 3 days after surgery, the investigator took the secretions from the wound site of the control group and the experimental group for bacterial culture examination.

Recording time: intraoperative (end of debridement) and 3 days postoperatively.

Analysis methods: According to Table 2, the bacterial situation of the wound in the two groups was scored, and the difference between the two groups was analyzed.

Secondary evaluation index 2: growth factor concentration.

Evaluation methods: Approximately 20mL of anticoagulant peripheral blood was collected, and it was evenly divided into PRP group and patch group. The upper layer of plasma and platelets were obtained after centrifugation at 150×g for 10 minutes, and the platelet-containing plasma was transferred to a new centrifuge tube againCentrifuge 800×g for 5 minutes, discard 3/4 of the supernatant, mix the lower layer well to obtain platelet-rich plasma, add 1/10 volume of thrombin to form a gel and put in 50 In a mL centrifuge tube, add 4 times the volume of normal saline at 37°C for 1 hour.

According to the product manual, platelet-containing plasma and 1/10 volume of thrombin were mixed in a disposable gel patch former, and then extruded into gel patches.× Place the patch in a 50mL centrifuge tube and add 4 times the volume of normal saline to 37 °C for 1 h. After the extraction, the gel and gel patch were removed, and the concentrations of PDGF-BB, TGF-β1 and IL-1β were detected with the ELISA kit.

Recording time: within 12 hours after the preparation of PRP gel and gel patch is completed.

Analysis methods: The concentration of growth factors released by PRP gel and gel patch was detected according to the evaluation method, and the difference analysis between groups was carried out.

Secondary evaluation index 3: ultimate tensile strength.

Evaluation methods: The remaining platelet-rich plasma (PRP group) and gel patch (patch group) were taken for tensile strength testing.

In the PRP group, 1.8mL of platelet-rich plasma and 1/10 volume of thrombin were added to φ35 mm round cake dish to form a gel.

The maximum tensile force that the gel can withstand is tested with a handheld tensile meter.

Recording time: within 3 hours after the preparation of PRP gel and gel patch is completed.

Analysis methods: The maximum ultimate tensile force of PRP gel and gel patch was recorded according to the evaluation method, and the difference analysis between groups was performed to verify the effectiveness of the product in enhancing the gel tensile force.

Secondary evaluation criterion 4: postoperative wound condition

Evaluation method: 3 days after surgery, the investigator scored the wound of the subjects according to the "Table 3 Wound Assessment Form" to evaluate the wound infection. The Wound Assessment Form is as follows:

References:

Armstrong DG., et al. Diabetic Foot Ulcers: A Review. JAMA. 2023. Jul; 3; 330(1):62-75.

Recording time: 3 days postoperatively.

Analysis method: According to the evaluation method, the wound conditions of the control group and the test group were scored 3 days after surgery, and the difference between the groups was analyzed.

Secondary evaluation indicator 5: product use performance

Evaluation method: The performance of the test instrument was evaluated by the surgical investigator after surgery, and the evaluation content was as follows:

Among the three dimensions of product performance, operation process, and preparation performance, at least one evaluation in each dimension is "yes", and at least 9 of the above 12 evaluation contents are rated as "yes", and the performance evaluation is "satisfactory". Otherwise, the performance of the use is rated as "unsatisfactory".

Recording time: The day the surgery is completed.

Analysis method: According to the evaluation method and the following formula, the satisfaction of the performance of the test instrument is counted.

Secondary evaluation indicator 6: platelet concentration

Evaluation methods: The platelet concentrations of P RP group and patch group were obtained according to the measurement and calculation results in the main evaluation indicators. Analysis of differences between groups was performed.

Recording time: within 3 hours after the preparation of PRP gel patches.

Analysis methods: The platelet concentrations of PRP group and patch group were analyzed between groups.

Safety evaluation

Safety evaluation indicators: abnormal laboratory examination, vital sign examination, adverse events and serious adverse events.

Safety evaluation index 1: Abnormal laboratory examination

Evaluation methods: Blood routine, liver function, and kidney function were reviewed 3 days after surgery, and red blood cell count (RBC), white blood cell count (WBC), neutrophil ratio (NEUT%), and hemoglobin concentration () were recorded in blood routine HGB), platelet count (PLT) test results; The results of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in liver function were recorded. The results of creatinine (CRE), urea nitrogen (BUN) or urea (UREA) tests in renal function were recorded. Record blood C-reactive protein results. If the test results are normal or abnormal but not clinically significant, the results are judged to be normal, and if the test results are abnormal and clinically significant, they are treated as abnormal results.

Recording time: 3 days postoperatively.

Analysis method: Calculate laboratory abnormalities according to the evaluation method and the following formula.

Safety evaluation index 2: vital sign examination

Evaluation methods: Basic vital signs were reviewed 3 days after surgery, and body temperature, pulse, respiration, and blood pressure were recorded.

Recording time: 3 days postoperatively.

Analysis method: According to the evaluation method, the vital signs of the experimental group and the control group were recorded 3 days after surgery, and the difference between groups was analyzed.

Safety evaluation index 3: occurrence of adverse events and serious adverse events

Evaluation methodology: Any adverse medical event during the trial, whether or not device-related, is an adverse event. Serious adverse events are determined if they occur during the course of a clinical trial that result in death or serious deterioration of health. All adverse events and serious adverse events should be determined to be related to the test device. The relationship between adverse events and serious adverse events and the test device is divided into "definitely related", "likely related", "possibly related", "possibly unrelated", "not related", and divided into adverse events, serious adverse events and device-related adverse events, Serious adverse events reflect the safety of the test device.

Expected adverse events of the test device include: device defects, wound discomfort, wound infection, etc.

Device defects: refers to whether there are functional failures such as broken device packaging and equipment damage during surgery.

Wound discomfort: refers to the occurrence of severe pain, numbness, and itching in the wound after surgery.

Wound infection: refers to whether wound infection occurs after surgery.

Note: Conditions related to clinical diagnosis and previous underlying disease (based on baseline examination or past medical history) may not be reported as adverse events if the severity and treatment do not change.

Recording time: From the time the subject is confirmed to enroll to the group 3 days after surgery.

Analysis methods: Adverse events and serious adverse events that occurred during the trial were recorded according to the evaluation method, and the incidence of adverse events and serious adverse events was calculated according to the following formula, and the difference analysis between groups was carried out.

Statistical analysis methods

Analyze the dataset

Full Analysis Set (FAS): A full analysis set is as close as possible to include all randomized subjects and should generally include all enrolled subjects who have used a device/received a single treatment, and only in very limited cases can exclude subjects, including cases where important enrollment criteria have been violated and there is no observational data after enrollment.

Conformance set (PPS): Conformance set is a subset of the full analysis set, including subjects who have received the treatment specified in the protocol, have observed data for the primary endpoint, and have no significant violations of the trial protocol.

Safety Analysis Set (SS): The safety dataset should generally include all enrolled subjects who have used a device/treatment once and have undergone a safety evaluation.

Note: If subjects are excluded from the full analysis set and the conformance set, one must meet the definition in the protocol, and the other must fully explain the reason for exclusion, and the reason for exclusion must be clarified during the blind review.

Subject Exclusion Criteria

In the following three situations, it is necessary to decide whether to remove them after discussion in the data review stage.

Subjects who do not meet the inclusion criteria;

Subjects who meet the exclusion criteria;

Subjects who violate/deviate from the protocol.

Statistical analysis methods

Statistical software: SPSS 29 statistical analysis software was used.

Basic principle: All statistical tests are two-tailed tests, and a P value of less than or equal to 0.05 will be considered to be statistically significant for the difference tested.

The description of the quantitative indicator will calculate the mean, standard deviation, median, minimum, maximum.

The description of classification indicators uses the number of examples and percentages of various categories.

Statistical analysis should include at least the following parts:

a. Description of clinical trial completion: including the overview of clinical trials (number of enrolled, completed, number of people lost to follow-up/withdrawn/eliminated, etc.), and list of incomplete cases and cases that have not entered each population;

b. Baseline description: Baseline demographic indicators and other relevant medical history indicators should be described; The t-test was used for the normality and homogeneity of variance, the non-parametric test was used for the non-normality test, and the corrected t-test was used for the normality but not the homogeneity of variance.

c. Effect evaluation: In addition to the point estimate, the 95% confidence interval of the point estimate should be given, and the lower limit of the 95% confidence interval of the overall rate difference should be compared with the pre-specified superior threshold in the scheme to determine whether the test device is satisfied Superior hypothesis.

Statistical evaluation methods

Effectiveness evaluation

The main evaluation index was performed by the confidence interval method, the pass rate of platelet concentration in the experimental group and the control group was counted, and the lower limit of the confidence interval between the experimental group and the control group was calculated , ∞] is completely within the range of [ ∆, ∞], or C_L > ∆, and the conclusion of superiority can be drawn。

The difference test was used for the secondary evaluation indicators, the t-test was used for the normality and variance homogeneity of the measurement data, the non-parametric test was used for the non-normality test, and the corrected t-test was used for the normality but not the homogeneity of variance. The chi-square^test or Fisher exact test was used for counting.

Safety evaluation

The safety index was tested by difference, the t-test was used for the normality and homogeneity of the variance, the non-parametric test was used for the non-parametric test that did not conform to the normality, and the corrected t-test was used for the normality but not the homogeneity of variance. The chi-square^test or Fisher exact test was used for counting.

Handling of missing and outliers

All missing, unused, or erroneous data (including withdrawals and withdrawals) and unreasonable data shall be discussed and finalized by researchers and biostatisticians. The basic statistical principles for the processing of these data are as follows:

Describe the details of each subject who drops out;

Missing data from baseline can be estimated without estimation;

Wrong and unreasonable data can be treated as missing values;

Missing values for all safety indicators are not estimated.

Clinical trial results

Analyze the dataset

Enrolled cases and safety analysis population

A total of 41 subjects were screened in this trial, 1 case failed screening, 2 cases withdrew from the screening period, and finally 38 cases were successfully enrolled. Thirty-eight cases were included in the FAS analysis set, 38 cases in accordance with the protocol set (PPS), and 37 cases in the safety analysis set (SS).The number of cases in each analysis set reached the statistical requirement of 36.

Table 4 Basic information of enrolled cases

Table 5 Safety and efficacy analysis population

Dropouts, exclusions, deviations from the protocol Details of the case

The data of 38 subjects were comprehensively analyzed, and a total of 30 subjects deviated from the protocol. Among them, 1 subject was lost to follow-up, which affected the results of the safety evaluation index and did not affect the results of the primary evaluation index and most of the secondary evaluation indicators, which was a slight deviation and was not included in the safety analysis set (SS).

In addition, the remaining subjects had mild deviations, and because they did not affect the evaluation of the primary and secondary effectiveness indicators, they were included in the full analysis set (FAS), conformity set (PPS), and safety analysis set (SS).

The details of the cases of dropout, exclusion, and deviation from the protocol are shown in the table below.

Table 6 List of subjects dropped out, eliminated, and deviated from the protocol

Demographic data and baseline characteristic analysis

Demographic data

Demographic indicators include age, gender, height, weight.

The results of FAS-based analysis showed that the average age of the experimental group was (57.95±12.08) years old and that of the control group was (61.63±7.05) years, and the difference between the groups was not statistically significant (P>0.05). There were 18 males in the experimental group, accounting for 94.74% and 1 female, accounting for 5.26%. In the control group, there were 13 males, accounting for 68.42% and 6 females, accounting for 31.58%, and the difference between groups was not statistically significant (P>0.05). The average height of the experimental group was (169.39±7.23) cm, and that of the control group was (168.01±8.388) cm, and the difference between the groups was not statistically significant ( P>0.05）。 The average weight of the experimental group was (68.41±11.99) kg, and the average weight of the control group was (64.42±9.96) kg, and the difference between the groups was not statistically significant (P% 3E0.05）。

Table 7 Demographic data (FAS).

Past history

Anamnesis includes past medical history and allergy history.

The results of analysis based on FAS showed that there were 19 subjects in the experimental group with a past medical history, accounting for 100%, and 0 subjects with no past medical history, accounting for 0%. In the control group, there were 19 subjects with a history of medical history, accounting for 100%, and 0 subjects with no past medical history, accounting for 0%. There were 19 subjects in the experimental group, accounting for 100%, and 0 subjects with no history of drugs, accounting for 0%； In the control group, there were 19 subjects with a history of drug use, accounting for 100%, and 0 subjects with no drug history, accounting for 0%。 In the experimental group, there were 2 subjects with allergy history, accounting for 10.53%, and 17 subjects without allergy history, accounting for 89.47%. 1 subject in the control group had a history of allergy, accounting for 5.26%), and 18 subjects had no allergy history, accounting for 94.74%, and the difference between the groups was not statistically significant (P% 3E0.05）。

Table 8 Subjects' anamnesis (FAS).

Wound size

The results of FAS-based analysis showed that there were 11 subjects in the experimental group with small and superficial wound size, accounting for 61.11%, and subjects with exposed joints or bones6 cases, accounting for 33.33%, and 1 case with extensive, deep and involving surrounding tissues, accounting for 5.56%; In the control group, 10 subjects with small and superficial wound size, accounting for 55.56%, and 2 subjects with exposed joints or bonescases, accounting for 11.11%, and 6 subjects with extensive, deep and involving surrounding tissues, accounting for 33.33%; There was no significant difference between groups (P>0.05).

Table 9 Wound size (FAS).

Debridement assessment score

The results of FAS-based analysis showed that the debridement assessment score of the experimental group was 1 2.58±0.96 points. The debridement assessment score of the control group was 12.58±0.96 points. There was no significant difference between groups (P>0.05).

Table 10 Debridement assessment score (FAS).

Study device use

The results of FAS-based analysis showed that the test group used gel patches prepared by the study device, model: YN-PAT 35, a total of 19example(100.00%); The control group was tested with platelet-rich plasma gel prepared by secondary centrifugation, with a total of 19 cases (accounting for 100.00%).

Table 11 Research device usage (FAS).

Effectiveness evaluation indicators

Main effectiveness evaluation indicators

The main evaluation index was the qualified rate of platelet concentration.

The results of FAS-based analysis showed that a total of 12 cases in the experimental group had qualified platelet concentrations and 7 cases had unqualified platelet concentrations, and the qualified rate of platelet concentrations was63.16%； In the control group, 2 cases had qualified platelet concentration, 17 cases had unqualified platelet concentration, and the qualified platelet concentration rate was 10.53 %； The difference between the groups was statistically significant (P<0.05). The difference in platelet concentration qualification rate between the two groups was 52.63% (95%CI: 22.02%~73.22%), of which 95% The lower limit of CI confidence interval was 22.02%, which was 10% higher than the superiority cut-off, inferring that the effectiveness of the experimental group was better than that of the control group.

The results of PPS-based analysis showed that a total of 12 platelet concentrations in the experimental group were qualified, and 7 platelet concentrations were unqualified, and the platelet concentration was qualified63.16%； In the control group, 2 cases had qualified platelet concentration, 17 cases had unqualified platelet concentration, and the qualified platelet concentration rate was 10.53 %； The difference between the groups was statistically significant (P<0.05). The difference in platelet concentration qualification rate between the two groups was 52.63% (95%CI: 22.02%~73.22%), of which 95% The lower limit of CI confidence interval was 22.02%, which was 10% higher than the superiority cut-off, inferring that the effectiveness of the experimental group was better than that of the control group.

Table 12 Platelet concentration rate pass rate (FAS).

Table 13 Platelet concentration rate pass rate (PPS).

Secondary effectiveness evaluation indicators

Bacterial condition of the wound 3 days after surgery

Wound bacteria at three days after surgery: In the full analysis set (FAS), the bacterial status score of the wound in the experimental group was (0.833±0.514, and the bacterial status score in the control group was (0.667±0.594 at three days after surgery ), and the difference between groups was not statistically significant (P>0.05). In the conformance protocol set (PPS), the bacterial status score of the wound in the experimental group was (0.833±0.514 at 3 days after surgery, and the bacterial status score of the wound in the control group was (0.667±0.594 at 3 days after surgery), and the difference between the groups was not statistically significant (P% 3E0.05）。

The results of PPS-based analysis showed that the bacterial score of the wound in the experimental group was (0.833±0.514 at three days after surgery, and the bacterial score of the wound in the control group was (0.667±0.594 at three days after surgery, and the difference between the groups was not statistically significant (P>0.05). ）。 In the PPS conformance set, the bacterial score of the wound was (0.833±0.514 in the experimental group and (0.667±0.594 in the control group at three days after surgery, and the difference between the groups was not statistically significant (P% 3E0.05）。

Table 14 Bacterial status (FAS) of wound wound at three days after surgery

Table 15 Wound bacterial status (PPS) at three days after surgery

Growth factor concentration

Concentration of growth factors: Based on the conformity to the protocol set (PPS), the concentration of growth factor PDGF-BB in the extract of the patch group was (5.89±4.35) pg/ The concentration of growth factor PDGF-BB in the extract of mL, PRP group was (7.13±5.16) pg/mL, and the difference between groups was not statistically significant (P>0.05). The concentration of growth factor TGF-β1 in the patch group was (2.52±2.42) ng/mL, and the growth factor TGF-β1 in the PRP group was in the extractThe concentration was (2.49±2.50) ng/mL, and the difference between groups was not statistically significant (P>0.05). The concentration of growth factor IL-1β in the patch group was (2.62±6.88) pg/mL, and the growth factor IL-1β in the PRP group was (2.626.88) pg/mL The concentration was (3.26±7.85) pg/mL, and the difference between the groups was not statistically significant (P>0.05).

Table 16 Concentration of growth factors