The Food and Drug Administration (FDA) has granted accelerated approval to Tarpeyo (budesonide) to reduce proteinuria in adults with primary immunoglobulin A nephropathy (IgAN) at risk of rapid disease progression, generally a urine protein-to-creatinine ratio (UPCR) of at least 1.5g/g.

The approval was based on data from a multicenter, randomized, double-blind phase 3 study ( Identifier: NCT03643965), which evaluated the efficacy and safety of Tarpeyo in 299 adults with biopsy-proven IgAN, estimated glomerular filtration rate (eGFR) of at least 35mL/min/1.73m2, and proteinuria (defined as either 1g/day or greater, or UPCR 0.8g/g or greater) who were on a stable dose of maximally-tolerated renin-angiotensin system (RAS) inhibitor therapy. Patients were randomly assigned 1:1 to receive Tarpeyo 16mg once daily or placebo for 9 months, followed by a 2-week taper of Tarpeyo 8mg once daily or placebo.

Results showed that treatment with Tarpeyo was associated with a 34% reduction in UPCR at 9 months compared with a 5% reduction for placebo (treatment difference, 31%; 95% CI, 16-42; P =.0001). The treatment effect was consistent across subgroups, including key demographic and baseline disease characteristics. The most common adverse reactions reported were hypertension, peripheral edema, muscle spasms, acne, dermatitis, increased weight, dyspnea, face edema, dyspepsia, fatigue, and hirsutism.

Tarpeyo contains 4mg of budesonide in a delayed-release capsule. The product is expected to be available in the first quarter of 2022.

Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory clinical trial. It has not been established whether Tarpeyo slows kidney function decline in patients with IgAN. 


  1. FDA grants Calliditas Therapeutics accelerated approval of Tarpeyo (budesonide) to reduce proteinuria in IgA nephropathy. News release. Calliditas Therapeutics. Accessed December 16, 2021.
  2. Tarpeyo. Package insert. Calliditas Therapeutics; 2021. Accessed December 16, 2021.