Hegelmaier_2025_Med__100776

BACKGROUND: Autoimmune encephalitides are a heterogeneous group of autoantibody-associated central nervous system disorders. The clinical course of autoimmune encephalitides can be life threatening, and treatment can be challenging. OBJECTIVE: This report describes a case of treatment-refractory, anti-diacylglycerol lipase alpha (DAGLA) antibody-associated autoimmune encephalitis successfully treated with chimeric antigen receptor (CAR) T cells. METHODS: Treatment was done by single intravenous infusion of fully human, second-generation CAR T cells (KYV-101) targeting CD19 and depleting B cells. Clinical response was measured by International Cooperative Ataxia Rating Scale and Clinical Assessment Scale in Autoimmune Encephalitis scores. Autoantibodies against DAGLA were measured by a recombinant cell-based indirect immunofluorescence assay in the serum and the cerebrospinal fluid and confirmed by staining of primary murine neurons and brain sections. FINDINGS: A 36-year-old man developed rapidly progressing generalized myoclonus, cerebellar head tremor, vertical binocular nystagmus, and tetraparesis despite treatment with pulse glucocorticoid therapy, plasma exchange, and rituximab. Anti-DAGLA antibodies were positive in the indirect immunofluorescence assay, in serum and cerebrospinal fluid, and reacted with neurons and brain sections. Due to his severe clinical condition and treatment refractoriness, the patient received a single infusion of autologous anti-CD19 CAR T cells. Clinical scores improved significantly after treatment, and anti-DAGLA antibody levels in serum and cerebrospinal fluid diminished. Oligoclonal bands in the cerebrospinal fluid were initially positive and became negative after CAR T cell therapy. CONCLUSION: The report highlights the therapeutic potential of anti-CD19 CAR T cell therapy in severe, treatment-refractory autoimmune encephalitis. FUNDING: There was no external funding for the treatment or the data generated.