To evaluate the safety and efficacy of ripertamab and its combination with tacrolimus in the initial treatment of MCD to provide a treatment regimen with higher remission rates, lower recurrence rates, and fewer side effects in patients with MCD.

Minimal change disease is the third most common primary kidney disease in adults with idiopathic nephrotic syndrome. The pathological features of the disease are no or only slight changes under light microscope, and the foot process fusion under electron microscope. The KDIGO guidelines recommend oral adequate doses of glucocorticoids as the initial treatment for adults with MCD. However, 48%-76% of patients relapse after tapering or gradual discontinuation of the drug, requiring a high cumulative dose of glucocorticoids. As the cumulative dose of glucocorticoids increases, the potential for side effects increases. In addition, 10% to 30% of patients frequently relapse, and 15% to 30% of these are steroid dependent. Therefore, the clinical goals for patients with MCD are to achieve early remission of proteinuria, reduce hormonal side effects, and more importantly, prevent the recurrence of proteinuria.

Inclusion Criteria:

1. Age 18-80 years old;
2. Primary minimal change disease confirmed by renal biopsy (Initial therapy);
3. 24h-UTP>3.5g/d or PCR>3500mg/g, and serum albumin<30g/L;
4. Agree to participate in the project and sign the informed consent.

Exclusion Criteria:

1. Secondary minimal change disease;
2. eGFR<60 mL/min/1.73m2;
3. Had history of mental disease, dysnoesia, serious cardiovascular and cerebrovascular diseases, pulmonary insufficiency, malignant tumors or other major diseases that are not suitable for clinical experiments;
4. Active bleeding in the gastrointestinal tract;
5. Prior treatment with corticosteroids or other immunosuppressants;
6. HBV, HCV, HIV or other untreated infections, congenital or acquired immunodeficiency diseases;
7. Have been vaccinated with live vaccine in the past four weeks;
8. Serum bilirubin > 3.6mg/dl for at least 1 month or liver function ≥3 times the upper limit of normal value;
9. Allergic to prednisolone, tacrolimus, or ripertamab;
10. Reluctance to use contraception or plan pregnancy/lactation within 6 months of study completion;
11. Had history of alcohol/drug abuse;
12. Unable to give informed consent.