Abstract
Three critically ill, chemotherapy-refractory patients with diffuse large B-cell lymphoma (DLBCL) received loncastuximab tesirine in conjunction with standard therapies for secondary malignancy-associated hemophagocytic lymphohistiocytosis (Mal-HLH). All patients were treated inpatient, with one requiring intubation on the day of administration. Each patient had an H-score >238, indicating a >98% probability of HLH. A significant reduction in ferritin levels was observed in two patients, and one patient achieved a complete response (CR). Loncastuximab tesirine demonstrated promise in managing Mal-HLH where previous treatments had failed. This study suggests that loncastuximab tesirine exhibits favorable activity and should be considered a valuable addition to the treatment options for Mal-HLH driven by DLBCL.