Super-refractory status epilepticus during blinatumomab initiation for B-cell acute lymphoblastic leukemia

Seizures have been reported as an adverse effect of blinatumomab, a bispecific T-cell engager monoclonal antibody, which is mainly used for the treatment of pediatric relapsed/refractory leukemia. Here, we present the first reported case of super-refractory status epilepticus in an 11-year-old boy with B-cell acute lymphoblastic leukemia (B-ALL) while receiving blinatumomab. Our patient had a complete return to baseline despite enduring encephalopathy, refractory subclinical seizures requiring prolonged therapeutic burst suppression and MRI signal changes. This case demonstrates that super-refractory status epilepticus is a possible neurotoxic adverse effect of blinatumomab treatment, which responds well to conventional protocols for acute refractory seizures. Plain language summarySeizures are a known side effect of blinatumomab, a relatively new immunotherapy drug, which is mainly used for the treatment of relapsed leukemia in children. Here, we present the first reported case of seizure continuing for more than 24 h despite appropriate antiseizure treatment while also receiving blinatumomab. Despite an extended period of altered mental status, new abnormalities on imaging of the brain and a medication-induced coma to treat unrelenting seizures, our patient returned completely to his healthy brain function. This case demonstrates that seizures, which are especially difficult to treat, can be associated with blinatumomab immunotherapy for pediatric refractory B-ALL; however, standard-tiered seizure treatments can be effective.