Emapalumab, approved by the FDA in 2018, is currently the only drug indicated for refractory or relapsed primary HLH in children (including neonates) and adults.460,461 Other promising agents include the JAK1/2 inhibitor ruxolitinib, the CD52 monoclonal antibody alemtuzumab, IL-6 inhibitors, IL-1Ra anakinra, IL-18 inhibitors and TNF inhibitors.456 Additionally, gene therapy approaches targeting defective genes associated with XLP1, FHL2, and FHL3 have shown encouraging results in preclinical mouse models, offering potential avenues for future curative treatments.462–464. Here, IL18 is linked to hemophagocytic syndrome.