Telitacicept reduced the 24-hour urine protein-to-creatinine ratio by 55% compared to placebo at 39 weeks (p < 0.0001) in Stage A of a Phase 3 study in adults with IgA nephropathy in China, with a favorable safety profile reported. The core event is RemeGen’s confirmation that the randomized, double-blind, placebo-controlled, multicenter trial (n=318) met its primary endpoint for proteinuria in patients already on standard therapy. The company plans to submit a BLA to China’s CDE, positioning telitacicept for what could become its fifth approved indication in China. Complete data are slated for presentation at an upcoming medical meeting. Vor Bio, which is collaborating on telitacicept globally across autoimmune indications, highlighted the relevance of UPCR as a recognized regulatory marker in IgAN. The China program complements ongoing global development for other indications, including a Phase 3 trial in generalized myasthenia gravis. Strategically, this is a fast-follower but increasingly credible play in the BAFF/APRIL space, where dual inhibition has become the most closely watched upstream approach in IgAN.
A 55% placebo-adjusted reduction in proteinuria is competitive with top-line signals seen from other mechanistic peers. It exceeds what traditional background therapies achieve, strengthening the case for a surrogate-based filing in China. The design suggests a staged path: Stage A delivers the proteinuria win needed for submission. In contrast, either Stage B or post-marketing commitments will likely need to address eGFR slope and hard renal outcomes—consistent with how global regulators have managed recent IgAN approvals. The move also underscores a China-first development and commercialization cadence, leveraging a large endemic patient base and responsive regulator, while leaving open how—and how quickly—the dataset can be translated into ex-China opportunities. For stakeholders, the near-term effects diverge by region. Chinese sites and CROs should prepare for long-term follow-up infrastructure geared to renal function trajectories, immunoglobulin monitoring, and infection surveillance typical of B-cell–modulating therapies. For sponsors, the readout tightens the competitive race across BAFF/APRIL-targeted assets and raises the bar for the magnitude and durability of proteinuria reductions. Regulators will focus on immunologic safety signals and the relationship between proteinuria reductions and eGFR preservation over time, an area where class effects and dose optimization continue to be scrutinized. Vendors—particularly central laboratories—can expect sustained demand for standardized UPCR workflows and immunoglobulin panels to support both regulatory submissions and pharmacovigilance activities. For patients and prescribers, an additional mechanism beyond corticosteroids, RAS blockade, SGLT2 inhibitors, and sparsentan broadens options, while operationalizing tighter safety monitoring, typical of upstream B-cell pathway inhibitors. The following inflection points are clear. Detailed disclosures need to clarify absolute UPCR changes, responder distributions, eGFR slope data to date, hematuria trends, and the incidence of infections and hypogammaglobulinemia. The CDE’s review will indicate whether approval is conditional on outcomes data and will signal the weight China places on proteinuria as a standalone basis for licensure in 2025–2026. Outside China, watch for whether Vor Bio and partners move to a bridging or complete global Phase 3 in IgAN, how they position telitacicept against other APRIL/BAFF programs, and whether manufacturing, supply, and pharmacovigilance frameworks are scaled for multi-indication use. The open risks are durability and generalizability: sustaining proteinuria reductions alongside preserved eGFR in diverse populations, maintaining an acceptable immunologic safety margin, and navigating crowded trials that compete for the same IgAN patient pool.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
