Photo Credit: iStock.com/jitendrajadhav

The following is a summary of “Fluctuations in serum aquaporin-4 antibody titers: the clinical significance in neuromyelitis optica spectrum disorder,” published in the May 2025 issue of Journal of Neurology by Wang et al. 

Researchers conducted a retrospective study to assess the link between aquaporin-4 immunoglobulin G (AQP4-IgG) titer dynamics and relapse in neuromyelitis optica spectrum disorder (NMOSD) and to compare titer changes across therapies. They identified factors associated with antibody seroreversion to negativity. 

They included 171 patients with at least 2 serum AQP4-IgG tests by fixed cell-based assay 30 days apart and at least one positive result. They reviewed clinical and treatment data. 

The results showed that among 171 patients with NMOSD had a median disease duration of 81.3 months, 44 (25.7%) became AQP4-IgG seronegative with a reduced annualized relapse rate (0.16 vs. 0.00, P < 0.001). Decline in AQP4-IgG titers were protective against relapse (HR 0.53, 95% CI 0.36–0.79, P = 0.002). Patients treated only with monoclonal antibodies had higher chances of seroreversion than those on non-specific immunosuppressants (HR 3.01, 95% CI 1.23–7.34, P = 0.016) or those switched from immunosuppressants to monoclonal antibodies (HR 6.17, 95% CI 2.13–17.54, P < 0.001). Male sex (OR 3.95, 95% CI 1.35–11.63, P = 0.012), baseline AQP4-IgG titer (OR 0.71, 95% CI 0.55–0.92, P = 0.008), and monoclonal antibody treatment throughout disease (OR 4.07, 95% CI 1.45–11.40, P = 0.008) were independently linked to seroreversion. 

Investigators found serum aquaporin-4 immunoglobulin G titer was related to relapse risk. They showed early initiation of monoclonal antibodies had a superior suppressive effect on AQP4 autoimmunity, which may help reduce optica nerve-related relapses in NMOSD. 

Source: link.springer.com/article/10.1007/s00415-025-13137-6