Low dose ruxolitinib plus HLH-94 protocol: A potential choice for secondary HLH

Abstract Hemophagocytic lymphohistiocytosis (HLH) is an immune-mediated syndrome resulting in cytokine storm. The uncontrolled cytokine storm leads to significant tissue damage and potentially life-threatening multiorgan failure. Conventional first-line treatment for HLH included HLH-94 protocol or HLH-2004 protocol. However, up to 30% of patients do not respond to first-line therapy. We reported 3 cases of secondary HLH/macrophage activation syndrome which were caused by lymphoma (2 cases) and adult-onset still's disease. They received low dose ruxolitinib plus HLH-94 protocol, and had rapid response to treatment without obvious adverse effects. Following the treatment, there was improvement seen in several disease markers, including fever, fibrinogen, serum ferritin, and liver function tests. Our report indicated that treatment with low dose ruxolitinib plus HLH-94 protocol might be a potential choice for secondary HLH, and clinical trials warrants to be further investigated in this treatment regimen.