Telitacicept as a BAFF/APRIL dual inhibitor: efficacy and safety in reducing proteinuria for refractory childhood IgA vasculitis nephritis.

Background: Persistent proteinuria is an independent risk factor for poor prognosis in immunoglobulin A vasculitis nephritis (IgAVN). Recent studies have shown that telitacicept effectively reduces proteinuria levels in patients with IgA nephropathy (IgAN). The treatment has been associated with a significant decrease in galactose-deficient IgA1 (Gd-IgA1) levels. This study aims to elucidate the effectiveness and safety of telitacicept in treating refractory childhood IgAVN.

Methods: This is a single-center, retrospective observational study of seven children with IgAVN who had previously received glucocorticoids and at least one immunosuppressive therapy but still exhibited proteinuria. Telitacicept was administered subcutaneously once a week. Dosage was 80 mg for individuals weighing < 40 kg and 160 mg for those weighing > 40 kg.

Results: The study encompassed seven children, comprising two boys and five girls, with a median age of 15 years. Among the participants, six children (85.7%) exhibited a reduction in proteinuria, ranging from - 23.6 to - 97.5% compared to baseline levels. Conversely, one child (14.3%) did not show any decrease in proteinuria. Throughout the follow-up period, two children (28.6%) achieved complete remission, characterized by proteinuria level below 0.2 g/day/1.73 m and negative dipstick test for blood. Additionally, all participants demonstrated a significant decline in urinary red blood cell counts. In terms of medication administration, all patients discontinued the use of steroids and immunosuppressants. Furthermore, there was a reduction in the incidence of hospitalizations. Importantly, no serious adverse reactions were reported.

Conclusions: Telitacicept has demonstrated both efficacy and safety in treating children with refractory IgAVN.