Enteric Budesonide Treatment in IgA Nephropathy

Targeted release formulation (TRF)-budesonide was the first drug approved by regulatory authorities for the management of IgA nephropathy (IgAN) but is not available in many countries. Enteric coated (EC)-budesonide is widely available, but there is a paucity of data in IgAN.

This study was a prospective, single arm, multicenter (n = 6) study of EC-budesonide (IgANEF formulation, 9 mg twice daily) on adult (age ≥ 18 years) patients with IgAN (n = 168) who were immunosuppressive naïve, on maximally tolerated supportive regimen. The primary outcome was urine albumin creatinine ratio (UACR; in %) reduction at 9 months. Secondary outcomes included estimated glomerular filtration rate (eGFR) change and proportion of patients achieving ≥ 30% and ≥ 50% UACR reduction at 9 months. A sub-roup analysis was performed for outcomes grouped by baseline proteinuria severity (UACR < 800 vs. > 800 mg/g creatinine) and kidney function (eGFR < 35 vs. > 35 ml/min per 1.73 m²).

The mean age of the cohort was 36.1 ± 11.0 years with 97 males (57.1%). At 9 months (n = 148), geometric mean UACR decreased by 66.3% (from 1732 to 583 mg/g, P < 0.001). UACR response rates were 88.5% for ≥ 30% reduction and 75.7% for ≥ 50% reduction. Mean eGFR improved +5.0 ml/min per 1.73 m² (P < 0.001, n = 137). The outcome was similar in subgroups of both UACR and eGFR. There were no serious adverse events reported requiring discontinuation.

In this prospective multicenter, single arm study of EC-budesonide in IgAN, the safety, proteinuria reduction, and eGFR stabilization were encouraging. The drug has promising efficacy in regions where other approved drugs are unavailable.