The investigators analyze the clinical outcome of steroid withdrawal protocol starting at 3 months after kidney transplantation using tacrolimus, Mycophenolate Mofetil (MMF), and basiliximab. This study is an open-label, prospective, controlled clinical trial in a single center. Those patients who fulfill the entry criteria could enter in this prospective controlled trial of steroid withdrawal three months after transplantation.

Those patients who fulfill the entry criteria enter in this prospective controlled trial of steroid withdrawal starting at three months after transplantation. The entry criteria include 1) no episode of clinically treated nor biopsy confirmed acute rejection up to entry; 2) serum creatinine level equal to or less than 2 mg/mL on three separate measurements; 3) no proteinuria (urine protein less than 1000 mg/24 hours; 4) tacrolimus trough level > 5 ng/ml without signs of nephrotoxicity; 5) agreement to follow the study protocol.

For the patients who enter into the protocol, prednisolone would be slowly withdrawn by 2.5 mg in every two weeks until 8 weeks after entering the protocol (5 months post-transplantation). The patients visit every week, and they are closely monitored with symptoms and signs, blood cell count, chemistry, and urinalysis.

Inclusion Criteria:

• Patients aged more than 13 years who received a primary kidney transplant
• Subject who is using CNI ± purine synthesis inhibitor + steroid without change within the past 3 months (except the dosage)
• serum creatinine < 2 mg/dL and the variation of serum creatinine < 30% during the past 3 months
• Proteinuria ≤ 1g quantified by 24 hour urine or spot urine protein/creatinine ratio < 1.0
• Subjects who agree with written informed consent

Exclusion Criteria:

• Subjects who received combined non-renal transplantation.
• Subject who received re-transplantation
• Deceased donor without a heartbeat
• Patients with hypersensitivity to Mycophenolate sodium, Mycophenolate acid or Mycophenolate Mofetil or to any of the excipients.
• Patient with HGPRT(Hypoxanthin e-guanine phosphoribosyl-transferase) such as Lesch-Nyhan syndrome and kelley-Seegmiller syndrome.
• HLA-identical living related donor
• ABO blood group incompatible
• HIV, HBsAg, or HCV Ab tests (+)
• Abnormal liver function test (AST or ALT or total bilirubin> upper normal limit x3) ANC < 1,500/μL or WBC < 2,500/μL or platelet < 750,000/μL
• Women who are either pregnant, lactating, planning to become pregnant in the next 12 months.
• Subjects with history of cancer, except successfully treated, localized nonmelanocytic skin cancer Subjects with clinically significant infections within the past 3 months.