FDA Accepts BLA for Povetacicept in IgA Nephropathy

The US Food and Drug Administration (FDA) has accepted the Biologics License Application (BLA) for accelerated approval of povetacicept in adults with IgA nephropathy (IgAN), with an assigned Prescription Drug User Fee Act (PDUFA) target action date of November 30, 2026.

Vertex Pharmaceuticals announced the decision on June 1, 2026, supported by positive data from a prespecified week 36 interim analysis of the ongoing phase 3 RAINIER trial, in which povetacicept achieved a 52% reduction in urine protein-to-creatinine ratio (UPCR) from baseline.

Povetacicept is an investigational engineered fusion protein and dual inhibitor of the BAFF (B-cell activating factor) and APRIL (a proliferation-inducing ligand) cytokines. Through its engineered TACI domain, povetacicept has demonstrated improved binding affinity, potency, pharmacokinetics, and tissue distribution compared with other APRIL, BAFF, and dual BAFF/APRIL inhibitors in preclinical studies.

The randomized, double-blind, placebo-controlled phase 3 RAINIER trial evaluated the efficacy of povetacicept in reducing proteinuria and preserving kidney function. The study enrolled 605 patients, who were randomized to receive 80 mg povetacicept administered subcutaneously every 4 weeks in addition to standard care or placebo.

The trial's primary endpoint was change in 24-hour UPCR at week 36. The 2 alpha-controlled secondary endpoints were change in serum galactose-deficient IgA1 (Gd-IgA1) and the proportion of patients achieving hematuria resolution at week 36. Exploratory endpoints included the proportion of patients achieving a 24-hour UPCR <0.5 g/g, a threshold consistent with recent Kidney Disease: Improving Global Outcomes (KDIGO) guidance.¹

For the first secondary endpoint, patients treated with povetacicept experienced a 77.4% reduction in Gd-IgA1 compared with a 9.1% increase in the placebo group, yielding a treatment difference of 79.3% versus placebo (P <.0001) from baseline.¹

For the second secondary endpoint, among patients with baseline hematuria, 85.1% of those receiving povetacicept achieved hematuria resolution compared with 23.4% of patients receiving placebo, yielding a treatment difference of 61.7% versus placebo (P <.0001).¹

Overall, povetacicept was generally safe and well tolerated, with most adverse events (AEs) characterized as mild to moderate.¹

References

1. Vertex Announces US FDA Acceptance of Biologics License Application for Accelerated Approval of Povetacicept in IgA Nephropathy | Vertex Pharmaceuticals Newsroom. Vertex Pharmaceuticals Newsroom. Published 2026. Accessed June 1, 2026. https://news.vrtx.com/news-releases/news-release-details/vertex-announces-us-fda-acceptance-biologics-license-application

2. Hillenbrand A. RAINIER: Povetacicept Reduces Proteinuria By 52.0%. HCPLive. Published March 9, 2026. Accessed June 1, 2026. https://www.hcplive.com/view/ranier-povetacicept-achieves-primary-and-all-secondary-endpoints-for-igan