Atacicept is a recombinant fusion protein for the treatment of IgA nephropathy (IgAN), a serious autoimmune kidney disease.
Atacicept works as a dual inhibitor of two key cytokines: BAFF (B-cell Activating Factor, also known as BLyS). APRIL (A PRoliferation-Inducing Ligand).
By binding to these cytokines, it blocks the activation of the TACI receptor on B cells.
This process reduces the production of galactose-deficient IgA1 (Gd-IgA1), the upstream autoantibody responsible for the glomerular inflammation and damage seen in IgAN.
ORIGIN Phase 3 and Phase 2b trials have shown:
Proteinuria Reduction: Participants achieved a 46% reduction from baseline in proteinuria (measured by UPCR) at 36 weeks.
Kidney Function: Long-term data (96 weeks) suggests stabilization of eGFR, shifting the decline profile toward that of the general population without kidney disease.
Safety: Generally well-tolerated, with a safety profile comparable to placebo in randomized trials.
Designed for at-home self-administration via a once-weekly subcutaneous injection.
Currently focused on IgAN, it has been studied for Lupus Nephritis (LN) and Systemic Lupus Erythematosus (SLE), though results in those areas have been mixed.
Treatment with atacicept results in a significantly greater reduction in proteinuria than placebo at 36 weeks in patients with IgA nephropathy.