Inclusion Criteria:

1. Male or female, 18 years of age or older.

2. Must have IgA nephropathy documented by kidney biopsy.

3. Must have greater than 1gm of proteinuria a day.

4. Must be on a stable dose of Angiotensin Converting Enzyme Inhibitor (ACEI) and/or
Angiotensin Receptor Blocking agent (ARB) for at least 4 weeks prior to screening.

Exclusion Criteria:

1. Low platelet count and neutrophil count within certain limits defined for enrollment.

2. Underlying peripheral neuropathy.

3. Having cardiac problems, such as myocardial infarction, heart failure, uncontrolled
angina, severe uncontrolled ventricular arrhythmias, or electrocardiographic evidence
of acute ischemia or active conduction system abnormalities.

4. Allergic to VELCADE®, boron or mannitol.

5. Female subjects who are pregnant or breast-feeding.

6. Recent use of investigational drug within 14 days before enrollment.

7. Having serious medical conditions and infections (including HIV,or hepatitis B or C)
or psychiatric illness likely to interfere with participation in the study.

8. Diagnosed or treated for cancer within 3 years of participation in the study, with
the exception of complete resection of basal cell carcinoma or squamous cell
carcinoma of the skin, and in situ malignancy, or low-risk prostate cancer after
curative therapy.