FDA grants accelerated approval to Voyxact (sibprenlimab-szsi) to reduce proteinuria in adults with primary immunoglobulin A nephropathy

On November 26, 2025, Otsuka Pharmaceutical Co., Ltd. (Otsuka) and its U.S. subsidiary OPDC officially announced that the U.S. FDA has approved Voyxact (sibeprenimab-szsi) through the accelerated approval pathway to reduce proteinuria in adult patients with primary immunoglobulin A nephropathy (IgAN) who are at risk of disease progression. This is a landmark regulatory event in the field of IgAN treatment, marking the first time that this disease has ushered in a biologically targeted therapy that directly targets key nodes of the pathogenic immune pathway.

1. WhyFDA chose to accelerate the approval of Voyxact

IgAN is a progressive glomerular disease centered on immune abnormalities, and proteinuria is widely considered to be an important indicator reflecting disease activity and risk of renal function deterioration. The FDA granted Voyxact accelerated approval based on "significant reduction in proteinuria", an internationally recognized surrogate endpoint, which reflects the regulatory agency's high regard for the unmet medical needs of IgAN.

In the interim analysis of the prospective phase III study, Voyxact showed a significantly better improvement in proteinuria than placebo within the short-term treatment window. This result was considered to have potential disease-modifying significance and became the core basis for its approval.

2.The mechanism of Voyxact: blocking the APRIL pathway

Voyxact is the world's first and currently only approved therapy targeting APRIL (A-proliferation-inducing ligand). APRIL plays a key upstream position in the classic "4-hit" pathogenesis model of IgAN, continuously driving immune complex deposition and glomerular inflammatory response by promoting the abnormal production of galactose-deficient IgA1 (Gd-IgA1).

By selectively blockingAPRIL signaling, Voyxact can reduce the level of pathogenic Gd-IgA1 in the circulation and cut off the immune source of continued disease progression from a mechanistic level. This is significantly different from traditional supportive care that focuses on "controlling the outcome."

3. Clinical research design and treatment population positioning

SupportThe Phase III study approved by the FDA is a multi-center, randomized, double-blind, placebo-controlled trial involving adult patients with IgAN who received standard supportive care. The research design emphasizes evaluating the gain value of Voyxact on the basis of ACE inhibitors, ARBs and some patients combined with SGLT2 inhibitors, which is closer to the real-world clinical path.

The main efficacy evaluation focuses on the changes in proteinuria at the 9th month of treatment. At the same time, the study is still under continuous follow-up. It is planned to verify whether it can truly slow down the decline of renal function through long-term eGFR changes, which will also determine whether it can obtain traditional full FDA approval in the future.

4. Clinical significance of safety and convenience of administration

Judging from the disclosed safety information,Voyxact is generally well tolerated, with most adverse reactions being mild to moderate, and most of them can resolve spontaneously without affecting the continuity of treatment. Common conditions included mild infections and injection site reactions, and no new serious safety signals were reported.

In terms of medication method,Voyxact adopts a subcutaneous injection and self-administration mode once every four weeks. This feature has practical advantages in the long-term management of chronic kidney disease, helping to improve patient compliance and reduce the burden of frequent medical visits.

5.Potential impact of Voyxact on the treatment landscape of IgAN

As the first IgAN approved drug targeting theAPRIL pathway, Voyxact not only broadens treatment options, but also promotes the conceptual transformation of IgAN treatment from "passive delay" to "mechanical intervention". For patients with persistent proteinuria and risk of progression, the drug's launch provides a new possible path for personalized treatment.

With the subsequent release of key renal function endpoint data,Voyxact is expected to further consolidate its position in the IgAN treatment system and may also provide an important reference for the targeted research and development of other immune-mediated kidney diseases.

Reference materials: UpdatedNovember 26, 2025, https://www.drugs.com/newdrugs/fda-grants-accelerated-approval-voyxact-sibeprenlimab-szsi-reduction-proteinuria-adults-primary-6678.html