Inclusion Criteria:

• Signed informed consent
• Female or male patient > 18 years
• Biopsy-verified IgA nephropathy
• Proteinuria: U-albumin >500 mg/24 h
• S-creatinine < 200 umol/L
• A minimum of four available sample results (U-albumin and S-creatinine) prior to inclusion in the study.

Exclusion Criteria:

• Severe gastrointestinal disorders which may impair drug effect, or other conditions which could modify the effect of the trial drug as judged by the investigator
• Consumption of an investigational drug within 30 days prior to enrolment
• Unacceptable blood pressure (treated or untreated), defined as a systolic value >150 mm Hg and/or diastolic >90 mm Hg
• Hyperlipidaemia defined as unacceptable levels of lipids according to the discretion of the Investigator
• Patients in whom an ACE inhibitor was introduced/changed during the last three months prior to enrolment
• Patients treated with immuno-suppressive drugs
• Patients unable to take oral medication
• Severe liver disease (defined as ASAT and/or ALAT and/or gamma-GT above twice the normal value).
• Uncontrolled (treated or untreated) congestive heart failure as judged by the Investigator
• Patients with diabetes
• Patients with current malignancy or history of malignancy during the last three years
• History or presence of psychological or psychiatric illness which may interfere with the patient´s ability to adhere to the protocol
• Alcohol or drug abuse (present)
• Patients unwilling to meet the requirements of the protocol
• Other medical or social reasons for exclusion at the discretion of the Investigator
• Use of drugs inhibiting the cytochrome P-450 enzyme CYP3A4 (including grape fruit juice)
• Kidney transplanted patients
• For women only: pregnant or breast feeding; unwilling to use adequate contraception during the study (only women of childbearing potential)