Efficacy and Safety of HN2301 in Autoimmune Diseases（AIDs）

Inclusion Criteria:

1. Patients aged between 18 and 69 (inclusive), of any gender, diagnosed with SLEaccording to the 2019 EULAR/ACR SLE diagnostic criteria;

2. A history of SLE for at least 6 months, having used a stable standard treatmentregimen for at least 8 weeks, with the dosage stabilized for 2 weeks, yet thedisease remains active or has relapsed; Standard treatment refers to the stable useof the following drugs alone or in combination: non-steroidal anti-inflammatorydrugs (NSAIDs), antimalarials, corticosteroids; immunosuppressants includingcyclophosphamide, methotrexate, azathioprine, mycophenolate mofetil, leflunomide,tacrolimus, cyclosporine, etc.; targeted drugs include belimumab, rituxima,eculizumab, rituximab, etc.

3. Oral corticosteroids are prednisone (or equivalent drug) ≥7.5mg/day and ≤30mg/day.If used in combination with immunosuppressants, there is no minimum daily doserequirement;

4. At least two immunosuppressants have been used in a standardized manner (includinghydroxychloroquine);

5. Screening period tests meet: positive blood antinuclear antibody (ANA), and/orpositive anti-ds-DNA antibodies, and/or hypocomplementemia;

6. Screening period SLEDAI-2K score ≥6 points. If scoring includes low complementand/or anti-ds-DNA antibodies, the score for SLEDAI-2K clinical symptoms (excludinglow complement and/or anti-ds-DNA antibodies) should be ≥4 points; SSc-meets theclassification criteria of ACR and EULAR, 10-35 in mRSS score; RA-meets theclassification criteria of ACR and EULAR, DAS28-ESR>3.2, ACPA possitive.

7. Appropriate bone marrow, coagulation, cardiopulmonary, liver, and kidney functions.Bone marrow function: ANC ≥1.5×10^9/L, ALC ≥0.8×10^9/L, Hb ≥80g/L. No use oftransfusions and growth factors allowed within 7 days prior to screening to meetthese requirements. Coagulation function: INR or APTT ≤1.5×ULN. Cardiac function:Echocardiography (ECHO) assessment of left ventricular ejection fraction (LVEF) ≥40%. Lung function: ≤CTCAE grade 1 dyspnea and SpO2 ≥92% (measured by pulseoximetry) while breathing indoor air. Liver function: ALT and AST ≤2.5×ULN, totalbilirubin <2.0mg/dL (Gilbert syndrome subjects total bilirubin <3.0mg/dL). Kidneyfunction: defined as creatinine clearance rate (Cockcroft-Gault) ≥50mL/min withoutneed for fluid assistance;

8. Non-pregnant/non-lactating participants, willing to adopt contraceptive measureswithin 12 months after drug infusion.

Exclusion Criteria:

1. Individuals with positive Hepatitis B surface antigen (HBsAg) and/or Hepatitis Bcore antibody (HBcAb), and Hepatitis B virus (HBV) DNA positivity or titers abovethe detection threshold; those with positive Hepatitis C virus (HCV) antibodies andHCV RNA positivity or titers above the detection threshold; individuals with HumanImmunodeficiency Virus (HIV) antibodies positivity, CMV DNA positivity or above thedetection limit; those with positive syphilis antigen or antibodies;

2. Presence of other uncontrolled active infections;

3. History of major organ transplantation (such as heart, lung, liver, kidney) or bonemarrow/hematopoietic stem cell transplantation;

4. Pregnant or breastfeeding women;

5. Receiving any mRNA-LNP product or other LNP medications within the past two years;

6. History of any of the following cardiovascular diseases within the last 6 monthsbefore screening: Class III or IV heart failure defined by the New York HeartAssociation (NYHA), myocardial infarction, unstable angina, uncontrolled orsymptomatic atrial arrhythmias, any ventricular arrhythmias, or other clinicallysignificant cardiac diseases;

7. History of live vaccine administration within the last 30 days;

8. Individuals with asthma, severe allergies;

9. Other conditions deemed inappropriate for participation in this clinical study bythe investigator.