Study of XL784 in Patients With Albuminuria Due to Diabetic Nephropathy

Inclusion Criteria: * Type 1 or Type 2 diabetes mellitus with albuminuria, observed within 3 months of screening * Prior to randomization, subject has a glomerular filtration rate (GFR) \>/= 40 mL/min * Prior to randomization, the subject has albuminuria defined as ACR \>/= 500 mg/g * Stable seated blood pressure at the screening visit and prior to randomization * Subject has been on a stable dose and schedule of an angiotension converting enzyme (ACE) inhibitor and/or an angiotension receptor blocker (ARB) for at least 3 months before first dose of study drug * If on antidiabetic medication, subject has been on a stable dose and schedule for at least 3 months prior to first dose of study drug * Sexually active subjects must use an accepted method of contraception during the course of the study and for 3 months after * Signed informed consent Exclusion Criteria: * Subject has participated in an investigational study and received an investigational drug within 30 days of the first dose of XL784 * Hemoglobin A1c (HbA1c) value of \>10% at screening * Subject has had either organ transplantation or is currently on immunosuppressive therapy * Non-steroidal anti-inflammatory drugs (NSAIDs) within 5 days of urine screening assessments * Current diagnosis of one or more of the following conditions: 1) infection requiring parenteral antibiotics, 2) urinary tract infection, 3) hepatic dysfunction or disease, 4) symptomatic congestive heart failure, 5) unstable angina pectoris, 5) serious cardiac arrhythmia * Clinically evident diabetic gastroparesis or motility disturbance * Proteinuria not due to diabetic nephropathy * Diltiazem or verapamil * Ongoing condition where treatment with NSAIDs is anticipated (aspirin \</= 325 mg/day is allowed) * Recent history of drug or alcohol abuse * Pregnant or breastfeeding female subjects * Known HIV and/or receiving anti-retroviral therapy * Known allergy or hypersensitivity to any component of XL784 formulation