In November 2015, a study published in the American Journal of Kidney Diseases conducted a double-blind randomized placebo-controlled trial on the effectiveness of mycophenolate mofetil (MMF) for the treatment of IgA nephropathy (IgAN). The results showed that treatment with MMF did not significantly reduce urinary protein levels. Previous randomized controlled studies evaluating the effectiveness of mycophenolate mofetil (MMF) in the treatment of IgA nephropathy (IgAN) have yielded inconsistent results. This study was a double-blind randomized placebo-controlled trial. Study procedure: A total of 52 pediatric, adolescent, and adult patients with biopsy-confirmed IgAN at 30 medical centers in the United States and Canada were enrolled in this study. Inclusion criteria: age between 7 and 70 years; urine protein/creatinine ratio (UPCR) ≥ 0.6 g/g (men) or ≥ 0.8 g/g (women); and assessed glomerular filtration rate ≥ 50 mL/min/1.73 m2 (≥ 40 mL/min/1.73 m2 if treated with angiotensin-converting enzyme inhibitors). Mean age was 32 ± 12 (SD) years; 62% male; 73% Caucasian. The investigators gave 94 patients a 3-month treatment with lenopril (or colesartan) combined with high-purity omega-3 fatty acids (Omacor). In addition to treatment with lenopril (or colesartan) combined with high-purity omega-3 fatty acids (Omacor [Pronova Biocare]), 52 patients who developed sustained UPCR ≥0.6 g/g (men) or ≥0.8 g/g (women) were randomized to the MMF treatment group and the placebo control group (target dose, 25 to 36 mg/kg/d). RESULTS: The results showed changes in UPCR after 6 and 12 months of MMF/placebo treatment, and after the end of 12 months of treatment. UPCR was performed on urine samples taken within 24 hours. The researchers performed Schwartz formula (age <18 years) or cockcroft-gault formula (age ≥18 years) calculations of glomerular filtration rate. A total of 44 patients eventually completed 6 months of MMF (n=22) and placebo (n=22) treatment. The trial was terminated early because the data monitoring committee found no benefit. No patients in the trial experienced complete remission (UPCR < 0.2 g/g). The randomized mean UPCRs and UPCRs at 6 months were 1.45 (95% CI,1.16 to 1.75) and 1.40 (95% CI,1.09 to 1.70) in the MMF group and 1.41 (95% CI,1.17 to 1.65) and 1.58 (95% CI,1.13 to 2.04) in the placebo group, respectively. The between-group difference in UPCR (MMF group: placebo group) was -0.22 (95% CI, -0.75 to 0.31; P = 0.4). There were no adverse events other than nausea (MMF group, 8.7%; placebo group, 3.7%). One patient in the MMF group withdrew during the trial. Limitations of this study include the small number of patients included and the short follow-up period. The results of the study suggest that treatment with MMF did not significantly reduce urinary protein levels in IgAN patients presenting with persistent proteinuria treated with lenopril/closartan in combination with Omacor.