Case report: Ruxolitinib as first-line therapy for secondary hemophagocytic lymphohistiocytosis in patients with AIDS.

Hemophagocytic lymphohistiocytosis (HLH) is a fatal immunological syndrome resulting from excessive production of inflammatory cytokines. The conventional therapies for HLH, which are based on cytotoxic agents, are not always efficacious and safe, especially in patients with severe immunodeficiency. Ruxolitinib, a strong inhibitor of Janus kinase (JAK) 1/2, has already been evaluated as salvage and first-line therapy for HLH. Despite its promising efficacy and tolerability in the treatment of secondary HLH, the efficacy and safety of ruxolitinib in HLH patients with HIV infection remain to be investigated. Two men (ages: 45 and 58 years) both presented at our hospital with a high fever. They were found to be HIV-positive with severe immunodeficiency and opportunistic infections. Their laboratory tests showed severe pancytopenia, hypofibrinogenemia, hypertriglyceridemia, and increased levels of inflammatory factors and ferritin. Hemophagocytosis was found in the bone marrow, and abdominal computed tomography or ultrasonography showed splenomegaly. Both patients were diagnosed with infection-induced HLH due to severe immunodeficiency. Given they were both highly immunocompromised, we chose ruxolitinib as a first-line treatment alternative to cytotoxic chemotherapy. Rapid remission of clinical symptoms and normalization of laboratory parameters were achieved after ruxolitinib therapy. Neither patient had any associated adverse drug reactions or other laboratory abnormalities. Both patients were eventually discharged and ruxolitinib was discontinued as their disease alleviated, and they did not show signs of relapse during the 3- and 5-month of follow-up examinations. We described two cases of AIDS-related secondary HLH treated with ruxolitinib. Our cases highlight the feasibility of using ruxolitinib as a first-line therapy in patients with HIV infection and secondary HLH. Nevertheless, the safety and efficacy of this novel treatment need to be evaluated in large clinical trials in the future.

Liu X ，Zhu X ，Zhou X ，Xie Y ，Xiang D ，Wan Z ，Huang Y ，Zhu B ... -  《Frontiers in Immunology》

Dose-escalating ruxolitinib for refractory hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a severe disorder characterized by excessive secretion of cytokines. Even with the recommended HLH-94/2004 regimen, over 30% of patients remain refractory to frontline therapy or relapse after an initial response, leading to poor clinical outcomes. Ruxolitinib, a JAK1/2 inhibitor targets key cytokines in HLH, has shown promising therapeutic effects. However, there has been little attention given to patients who do not respond to ruxolitinib and whether an escalating dose can provide a resolution. This study analyzed eight HLH patients who received dose-escalating ruxolitinib who had previously failed to respond to the general dose. The efficacy and safety were mainly analyzed. Overall, four out of eight (50%) patients achieved better remission after dose escalation. Two patients who only showed improvement with the general dose achieved complete remission (CR) after dose escalation, and the other two patients also achieved CR after dose escalation when they did not respond to the general dose. The median time to achieve the best overall response was 18.5 days (IQR 13.25-23.75 days). There was no correlation of treatment outcome with blood count, liver function, LDH, cytokines, ferritin levels, NK cell activity, or the time to initiation of ruxolitinib and maximum dosage. The etiology of HLH (p=0.029) and level of sCD25 (p=0.021) correlated with treatment response to dose-escalating ruxolitinib. The area of sCD25 under the ROC curve was 0.8125 (95% CI 0.5921 to 1.033, p=0.035) when using 10,000 pg/ml as the cut-off value for predicting therapeutic effects. After a median follow-up of 159 days, two patients died, and the estimated 2-month overall survival rate was 75%. Adverse effects possibly related to the dose-escalating of ruxolitinib included two cases of extremity pain and one of aminotransferase increased. No grade 3 or higher adverse events were reported. This is the first comprehensive study on the use of dose-escalating ruxolitinib in HLH. Ruxolitinib at an escalated dose represent a viable and relatively safe solution for managing refractory HLH. The levels of sCD25 (with a cut-off of 10000pg/ml) can serve as an indicator for early consideration of chemotherapy during treatment.

Song Y ，Li X ，He X ，Zhou F ，Du F ，Wang Z ，Chen S ，Wu D ... -  《Frontiers in Immunology》

Ruxolitinib for secondary hemophagocytic lymphohistiocytosis: First case report.

Hemophagocytic lymphohistiocytosis (HLH) is an immune-mediated disorder resulting in hyper-activation of inflammatory cytokines. If left untreated, the uncontrolled inflammatory response can lead to significant tissue injury and potentially life-threatening multi-organ dysfunction. Conventional immunosuppressive agents are available for the management of HLH, including dexamethasone, cyclosporine, and etoposide; however, patients may not respond to these therapies. Clinicians may turn toward alternative pharmacologic agents that likely have less clinical evidence. We describe a case of secondary HLH that did not respond favorably to conventional treatments. Serum inflammatory markers continued to rise significantly with clinical deterioration and worsening pancytopenia. The severe thrombocytopenia and neutropenia were deemed to have contributed to a spontaneous subdural hematoma and candidemia, respectively. Ruxolitinib, a Janus kinase (JAK) 1/2 inhibitor, was then utilized as a novel salvage therapy based on available in vivo murine data at the time. Following initiation, there was improvement seen in several disease markers, including serum ferritin, lactate dehydrogenase, fibrinogen, and liver function tests. However, the pancytopenia did not show signs of recovery. The patient ultimately expired after 7days of ruxolitinib treatment. It is unclear if the improvement in disease markers was attributed to JAK inhibition alone. However, this experience combined with the positive in vivo murine data suggests that ruxolitinib may serve as a potential treatment option for HLH, pending the release of more robust data. To our knowledge, this is the first human case report describing the use of ruxolitinib for HLH. Future studies are warranted to determine the role of ruxolitinib in this setting.

Sin JH ，Zangardi ML 《-》

Short-term effectiveness of ruxolitinib in the treatment of recurrent or refractory hemophagocytic lymphohistiocytosis in children.

Wei A ，Ma H ，Li Z ，Zhang L ，Zhang Q ，Wang D ，Lian H ，Zhang R ，Wang T ... -  《-》

Ruxolitinib for the treatment of lymphoma-associated hemophagocytic lymphohistiocytosis: A cautionary tale.

Trantham T ，Auten J ，Muluneh B ，Van Deventer H ... -  《-》