The objective of this study is to evaluate the effects of tacrolimus sustained-release capsules replacing cyclosporin on kidney function of renal transplant recipients.

Inclusion Criteria:

• 18-65 years of age, male or female
• 1-5 years after kidney transplantation
• The patient has been accepting cyclosporin-based immunosuppressive therapy for ≥6 months, and the therapeutic regimen has kept stable for at least 4 weeks before inclusion
• The dose of cyclosporin has kept stable for at least 4 weeks before inclusion
• At least one of the cyclosporin-related adverse reactions is present or the answer to the 5th question in the questionnaire is "Yes" at the time of inclusion:
• gingival hyperplasia and treatment requested by the patient
• polytrichia and interventional therapy requested by the patient
• post-transplantation hypertension
• post-transplantation hyperlipemia (total cholesterol>5.7 mmol/L (220 mg/dl))
• Serum creatinine<200 μmol/l ( 2.3 mg/dl)
• A promise is made to take contraceptive measures during the study (women at childbearing ages).

Exclusion Criteria:

• Patients having accepted transplantation of other organs apart from kidney transplantation
• Patients with 24-hour urine protein>2 g
• Patients with SGPT/ALT, SGOT/AST or total bilirubin continually increasing to more than twice the normal value(s)
• Patients with refractory infectious foci
• Patients with serious diarrhea or vomiting, active upper gastrointestinal ulcers or malabsorption
• Patients with serious heart or lung diseases or history of sugar tolerance abnormality or malignant tumors
• Patients allergic to tacrolimus or other basic medications
• Pregnant or lactating women
• Patients having participated in other clinical trials within the previous month
• Other patients who are considered by doctors unsuitable for the study

Access to anonymized individual participant level data will not be provided for this trial. Further details on Astellas' data sharing policy can be found at https://www.clinicaltrials.astellas.com/transparency/.