Efficacy and safety of telitacicept in children with IgA vasculitis and IgA vasculitis nephritis: a single-center retrospective study.

BACKGROUND: Immunoglobulin A vasculitis (IgAV) is the most common childhood vasculitis and can lead to immunoglobulin A vasculitis nephritis (IgAVN) in severe cases, potentially progressing to kidney failure in a subset of children. Safer and more effective treatments are needed to improve outcomes in these children. This study aimed to evaluate the efficacy and safety of telitacicept in the treatment of children with IgAV and IgAVN. METHODS: This is a single-center, retrospective observational study of twenty four children with IgAV or IgAVN who received telitacicept treatment, and thirty matched children with IgAVN who only received conventional treatment were taken as the control group for children with IgAVN who received telitacicept treatment in acute phase. The treatment response was evaluated through urine protein, serum albumin, eGFR and serum immunoglobulin levels, and data was analyzed at telitacicept initiation and at 4, 12, 24 and 36 weeks after treatment. RESULTS: A total of twenty four children (thirteen boys and eleven girls) with IgAV (n = 5) and IgAVN (n = 19, comprising ten acute and nine chronic cases) were enrolled. All children with IgAV experienced improvement of skin, joint, and gastrointestinal symptoms after telitacicept treatment, with no kidney involvement during follow-up. In children with IgAVN, the urinary protein-to-creatinine ratio (UPCR) significantly decreased at 36 weeks compared to baseline (P < 0.05) in both acute and chronic groups, while estimated glomerular filtration rate (eGFR) remained stable (P > 0.05). In addition, the dose of steroids administered during the treatment with telitacicept was significantly reduced, the acute IgAVN group exhibited significantly greater steroid reduction between weeks 4 and 24 compared with the controls group (P < 0.05). Furthermore, serum immunoglobulin levels (IgA, IgG) significantly decreased 12 weeks after telitacicept treatment (P < 0.01), and no other adverse reactions observed. CONCLUSION: Telitacicept appears to be a promising therapy for children with IgAV and IgAVN, effectively inducing proteinuria remission, improving systemic symptoms, and reducing the use of steroids, with favorable safety.