Aurinia Pharmaceuticals has announced positive results from a Phase 1 single-ascending-dose study of aritinercept (AUR200), marking a significant milestone for the dual inhibitor of B cell-activating factor (BAFF) and a proliferation-inducing ligand (APRIL) in autoimmune disease treatment. The study demonstrated robust and long-lasting reductions in immunoglobulins with an excellent safety profile across all tested dose levels.
Strong Pharmacodynamic Activity Observed
The Phase 1 study investigated aritinercept doses ranging from 5 mg to 300 mg, administered by subcutaneous injection in 61 healthy subjects. Single doses of the investigational therapy led to substantial and sustained reductions in immunoglobulins, with mean reductions from baseline to Day 28 reaching up to 48% for immunoglobulin A (IgA), 55% for immunoglobulin M (IgM), and 20% for immunoglobulin G (IgG).
These pharmacodynamic effects support the potential for once-monthly dosing, which could offer significant convenience advantages for patients with autoimmune diseases requiring chronic treatment.
Favorable Safety Profile Across All Dose Levels
Aritinercept demonstrated excellent tolerability across all tested dose levels. The study reported no treatment-related Grade ≥3 adverse events, no treatment-related serious adverse events, and no discontinuations due to treatment-related adverse events. The most common adverse events included injection site reactions (24% aritinercept vs. 13% placebo), headache (11% aritinercept vs. 7% placebo), upper respiratory tract infection (7% aritinercept vs. 0% placebo), and back pain (4% aritinercept vs. 0% placebo). Notably, all injection site reactions were Grade 1 in severity.
Mechanism of Action and Clinical Potential
"Dual inhibition of BAFF and APRIL to modulate B cells, including plasma cells, holds great promise in the treatment of a wide range of autoimmune immune diseases where these cells produce disease-causing autoantibodies," said Dr. Greg Keenan, Chief Medical Officer of Aurinia.
The dual targeting approach represents a potentially significant advancement in autoimmune disease treatment, as both BAFF and APRIL play crucial roles in B cell survival and antibody production. By inhibiting both pathways simultaneously, aritinercept may offer superior efficacy compared to single-target approaches.
Next Steps in Clinical Development
Based on these encouraging Phase 1 results, Aurinia plans to initiate clinical studies of aritinercept in at least two autoimmune diseases in the second half of 2025. The company's confidence in advancing the program reflects the strong pharmacodynamic profile and favorable safety data observed in the current study.
Aurinia, which already markets LUPKYNIS (voclosporin) as the first FDA-approved oral therapy for active lupus nephritis, continues to focus on delivering therapies for autoimmune diseases with high unmet medical needs. The development of aritinercept represents the company's expansion into novel mechanisms of action for treating these challenging conditions.
