Safety and Efficacy Study Using Gene Therapy for Critical Limb Ischemia (NL003-CLI-III-2)

Inclusion Criteria:

1. At the age of 20 and 80 (at the time of signing the informed consent), bothmale and female.

2. According to DSA or CTA, patients diagnosed with lower limb arterial ischemicdisease based on the medical history and clinical manifestations and withRutherford grade 5 (with ulcer) must meet the substandardProspective.(if bothlimbs of the subject suffer from lower limb arterial ischemic disease, it is upto the investigator to select one limb for the study.)Resting ankle systolicpressure (dorsal foot artery or posterior tibial artery) ≤70mmHg or ABI≤0.5 orTcPO2 < 30mmHg;In the first 3 months after randomized inclusion, DSA or CTAconfirmed severe stenosis (≥70%) or occlusion of superficial femoral artery orpopliteal artery or inferior knee artery.

3. Patients with chronic lower limb arterial ischemia complicated with ulcerationalso met the following requirements: when signing the informed consent, theischemic ulcer of the artery lasted at least 2 weeks;When signing the informedconsent, the area of a single ulcer is no more than 10cm2;If there are multipleulcers in the affected limb selected at the time of signing the informedconsent, the total number of ulcers shall not exceed 3.Basic ulcer care (according to standard ulcer care procedure) should be maintained during thetest to avoid aggravation of infection.The ulcer did not expose bone or jointcapsule.If there is gangrene, only partial toe gangrene.

4. Agreed to use the basic treatment drugs as required during the test, and kept acomplete record of the subjects' diaries on time. The compliance of the basictreatment drugs and the subjects' diaries during the screening period was ≥70%.

5. Agree to use appropriate contraceptive measures during the experiment;Femalesubjects of reproductive age, blood pregnancy test negative.

6. Signed informed consent.

Exclusion Criteria:

1. Patients with acute lower limb ischemia or acute exacerbation of chronic lowerlimb ischemia.

2. Vascular reconstruction (bypass or intravascular therapy) or sympatheticresection or amputation was performed within 4 weeks prior to the signing ofthe informed consent.

3. Due to the surgical operation, the patient was still in the postoperative riskperiod, and the researcher judged that it was not suitable for the participant.

4. Main-iliac artery stenosis ≥70%.

5. Severe limb infection (cellulitis, osteomyelitis, etc.), distal fascia or boneexposure were observed.

6. Cardiac function NYHA class belongs to Ⅳ grading standards (see appendix 1).

7. Cerebral infarction, cerebral hemorrhage, myocardial infarction or unstableangina pectoris occurred within 3 months before signing the informed consent.

8. Refractory hypertension (systolic blood pressure ≥180mmHg or diastolic bloodpressure ≥110mmHg when taking three or more antihypertensive drugs).

9. Proliferative retinopathy and retinopathy examination is not available.

10. Inability to accurately describe symptoms and emotions.

11. Severe liver disease with uncompensated cirrhosis, jaundice, ascites orhemorrhagic varices.

12. Current recipients of immunosuppressants or chemoradiotherapy.

13. Anti-hiv antibody positive, anti-hepatitis c antibody positive and hepatitis bsurface antigen positive (if the subject is HBsAg positive and HBV DNA inperipheral blood is combined, the researcher believes that the subject'schronic hepatitis b is stable and will not increase the risk of the subject,the subject can be selected).

14. Results of laboratory examination during screening period: hemoglobin < 80g/L,white blood cell count < 3.0×109/L, platelet < 75×109/L, upper limit of normalAST or ALT >, upper limit of normal serum creatinine > was 3 times, or otherlaboratory examination indicators showed abnormalities that researchers thoughtmight affect the evaluation of test results.

15. Poor blood glucose control after treatment (glycosylated hemoglobin > 10%).

16. Previously diagnosed with malignant tumor, or any of the following test resultsdetermined by the investigator to be at risk of tumor: fecal occult bloodtest;Chest X-ray examination or chest CT examination;Alpha-fetoprotein (AFP),carcinoembryonic antigen (CEA) and ca19-9;Male subjects, prostate specificantigen test (PSA, free PSA);Female subjects: cervical smear (Pap),mammography/b-ultrasound, ca-125;The investigators determined that additionaltests were necessary to eliminate the tumor risk.

17. In the opinion of the investigators, patients with comorbidities that affectsafety and efficacy evaluation, or those with a predicted survival of less than 12 months.

18. Frequent drinkers within the 12 months prior to the signing of the informedconsent, i.e., those who drank more than 14 units of alcohol per week (1 unit =360 mL beer or 45 mL alcohol of 40% spirits or 150 mL wine) or substanceabusers.

19. Participate in other clinical trials within 3 months before signing theinformed consent.