Telitacicept, a BAFF/APRIL-targeting fusion protein by RemeGen, delivered a significant reduction in proteinuria in an interim analysis of a Phase 3 trial in high-risk IgA nephropathy. The NEJM-published results were reported after 39 weeks of treatment, based on a prespecified interim endpoint. In patients with biopsy-proven IgA nephropathy and persistent proteinuria despite supportive care, urinary protein-to-creatinine ratio reductions favored telitacicept over placebo. At week 39, proteinuria dropped 58.9% with telitacicept versus 8.8% with placebo, translating to a relative difference of -55.0% (P<0.001). Estimated GFR changes were less favorable in the placebo group, with no unexpected safety signals. Safety was a key focus: adverse events were more frequent with telitacicept (89.3%) than placebo (78.6%), while serious adverse events were less common (2.5% vs. 8.2%). The trial remains a milestone readout given telitacicept’s targeted approach to upstream immune drivers in IgA nephropathy.