Current strategies in the management of hypereosinophilic syndrome, including mepolizumab

From DREAM to REALITI-A and beyond: Mepolizumab for the treatment of eosinophil-driven diseases

Effective treatment of inflammatory diseases is often challenging owing to their heterogeneous pathophysiology. Understanding of the underlying disease mechanisms is improving and it is now clear that eosinophils play a complex pathophysiological role in a broad range of type 2 inflammatory diseases. Standard of care for these conditions often still includes oral corticosteroids (OCS) and/or cytotoxic immune therapies, which are associated with debilitating side effects. Selective, biological eosinophil‐reducing agents provide treatment options that improve clinical symptoms associated with eosinophilic inflammation and reduce OCS use. Mepolizumab is a humanized monoclonal antibody that binds to and neutralizes interleukin‐5, the major cytokine involved in eosinophil proliferation, activation, and survival. Mepolizumab is approved for the treatment of severe eosinophilic asthma, eosinophilic granulomatosis with polyangiitis and hypereosinophilic syndrome. Additionally, the efficacy of add‐on mepolizumab has been observed in patients with severe chronic rhinosinusitis with nasal polyposis and chronic obstructive pulmonary disease with an eosinophilic phenotype. Here, we review the development, approval, and real‐world effectiveness of mepolizumab for the treatment of patients with severe eosinophilic asthma, from the DREAM to REALITI‐A studies, and describe how knowledge from this journey extended to the use of mepolizumab and other biologics across a broad spectrum of eosinophilic diseases.

Budd-Chiari Syndrome Associated With Hypereosinophilic Syndrome Treated by Deceased-Donor Liver Transplantation: A Case Report

INTRODUCTION

Budd-Chiari syndrome (BCS) associated with hypereosinophilic syndrome (HES) is very rare, and only a few reports have described its treatment. Furthermore, no report to date has described the performance of liver transplantation for the treatment of BCS associated with HES. We herein describe a 54-year-old man who underwent deceased-donor liver transplantation (DDLT) for treatment of BCS associated with HES.

CASE

A 54-year-old man was found to have an increased eosinophil count during a medical check-up. After exclusion of hematopoietic neoplastic diseases and secondary eosinophilia, idiopathic hypereosinophilia was diagnosed. Oral prednisolone was administered to the patient, and his eosinophil count immediately decreased to a normal level. He had an uneventful course without complications for 11 months but then presented with bloating and malaise. Imaging studies including ultrasonography, enhanced computed tomography, and angiography revealed BCS associated with HES. Transjugular intrahepatic portosystemic shunt failed because of complete obstruction of the hepatic veins. Therefore, the patient was introduced to our hospital for liver transplantation. DDLT was performed with venovenous bypass 1 month after the patient was placed on the DDLT waiting list. The explanted hepatic veins were completely occluded and organized. The patient's eosinophil count was maintained at a normal level with prednisolone treatment after DDLT.

CONCLUSIONS

Liver transplantation can be a treatment option for BCS associated with HES if neoplastic diseases and secondary eosinophilia have been excluded. Life-long oral steroid therapy is required to control HES even after liver transplantation.

Thrombosis in the portal venous system caused by hypereosinophilic syndrome: A case report

RATIONALE

Extensive thrombosis in the portal venous system caused by hypereosinophilic syndrome (HES) is rare, and there is no consensus on anticoagulant and thrombolytic treatments for arteriovenous thrombosis caused by HES.

PATIENT CONCERNS

The clinical data of a patient with extensive thrombosis in his portal venous system (superior mesenteric, splenic, hepatic, and portal veins), renal artery thrombosis, and mesenteric thrombosis caused by HES with secondary gastrointestinal bleeding and intestinal necrosis were retrospectively analyzed. Before admission, his eosinophil count increased to 7.47 × 10/L, and HES had been confirmed via bone marrow cytology. The patient experienced fever, cough, abdominal pain, massive hematemesis, and hematochezia that developed in succession. Abdominal computed tomography showed portal vein and superior mesenteric vein thromboses.

DIAGNOSIS

Hypereosinophilic syndrome; extensive thrombosis in the portal venous system; acute eosinophil-associated pneumonia; gastrointestinal bleeding; intestinal necrosis.

INTERVENTIONS

The patient was first treated with methylprednisolone, plasma exchange/hemofiltration, and single or combined use of unfractionated heparin and argatroban for anticoagulation. He was also administered alteplase and urokinase, successively, for thrombolytic treatment. Once the thromboses finally disappeared, the patient underwent surgery to excise a necrotic intestinal canal.

OUTCOMES

The thromboses disappeared with these treatments, and the patient recovered after the necrotic intestinal canal was excised.

LESSONS

The clinical manifestations of HES are complex and varied, and this condition can cause severe and extensive arteriovenous thrombosis. Anticoagulation therapy and thrombolysis are necessary interventions, and appear to be safe and effective.

Case for diagnosis. Erythroderma as manifestation of hypereosinophilic syndrome

Hypereosinophilic syndrome is defined as persistent eosinophilia (>1500/µL for more than six months) associated with organ involvement, excluding secondary causes. It is a rare, potentially lethal disease that should be considered in cutaneous conditions associated with hypereosinophilia. We report a case of erythroderma as a manifestation of hypereosinophilic syndrome. A 36-year-old male with no comorbidities presented progressive erythroderma, pruritus, peripheral neuropathy, and eosinophilia in the previous seven months. No mutations were found in FIP1L1/PDGFRA. Patient experienced rapid remission in response to oral prednisone and hydroxyurea. Cutaneous manifestations may be the only evidence of hypereosinophilic syndrome. Genotyping excludes myeloproliferative disease, thereby orienting treatment and prognosis.

Eosinophils and megakaryocytes support the early growth of murine MOPC315 myeloma cells in their bone marrow niches

Multiple myeloma is a bone marrow plasma cell tumor which is supported by the external growth factors APRIL and IL-6, among others. Recently, we identified eosinophils and megakaryocytes to be functional components of the micro-environmental niches of benign bone marrow plasma cells and to be important local sources of these cytokines. Here, we investigated whether eosinophils and megakaryocytes also support the growth of tumor plasma cells in the MOPC315.BM model for multiple myeloma. As it was shown for benign plasma cells and multiple myeloma cells, IL-6 and APRIL also supported MOPC315.BM cell growth in vitro, IL-5 had no effect. Depletion of eosinophils in vivo by IL-5 blockade led to a reduction of the early myeloma load. Consistent with this, myeloma growth in early stages was retarded in eosinophil-deficient ΔdblGATA-1 mice. Late myeloma stages were unaffected, possibly due to megakaryocytes compensating for the loss of eosinophils, since megakaryocytes were found to be in contact with myeloma cells in vivo and supported myeloma growth in vitro. We conclude that eosinophils and megakaryocytes in the niches for benign bone marrow plasma cells support the growth of malignant plasma cells. Further investigations are required to test whether perturbation of these niches represents a potential strategy for the treatment of multiple myeloma.

Clinical overview of cutaneous features in hypereosinophilic syndrome

The hypereosinophilic syndromes (HES) are a heterogeneous group of disorders defined as persistent and marked blood eosinophilia of unknown origin with systemic organ involvement. HES is a potentially severe multisystem disease associated with considerable morbidity. Skin involvement and cutaneous findings frequently can be seen in those patients. Skin symptoms consist of angioedema; unusual urticarial lesions; and eczematous, therapy-resistant, pruriginous papules and nodules. They may be the only obvious clinical symptoms. Cutaneous features can give an important hint to the diagnosis of this rare and often severe illness. Based on advances in molecular and genetic diagnostic techniques and on increasing experience with characteristic clinical features and prognostic markers, therapy has changed radically. Current therapies include corticosteroids, hydroxyurea, interferon-α, the tyrosine kinase inhibitor imatinib mesylate, and (in progress) the monoclonal anti-interleukin-5 antibodies. This article provides an overview of current concepts of disease classification, different skin findings, and therapy for HES.

Biologic modulators in allergic and autoinflammatory diseases

PURPOSE OF REVIEW

The advent of molecular techniques has resulted in the ability to tailor medications to specific protein targets. This review will emphasize several biological therapies, specifically directed toward cytokine receptors and inhibitors, and their role in the treatment of atopic and autoinflammatory diseases.

RECENT FINDINGS

Translational research and the identification of the molecular pathophysiology of diseases have led to more targeted treatment approaches. The biologic modulators encompassing monoclonal antibodies as cytokine inhibitors, receptor blocking antibodies, and new fusion receptors are now being applied to diseases beyond their original application.

SUMMARY

The expanded use of biological therapies has experienced success in the treatment of numerous disorders, especially in subsets of patients with disease that has been refractory to conventional therapies.

Animal models of asthma: value, limitations and opportunities for alternative approaches

Asthma remains an area of considerable unmet medical need. Few new drugs have made it to the clinic during the past 50 years, with many that perform well in preclinical animal models of asthma, failing in humans owing to lack of safety and efficacy. The failure to translate promising drug candidates from animal models to humans has led to questions about the utility of in vivo studies and to demand for more predictive models and tools based on the latest technologies. Following a workshop with experts from academia and the pharmaceutical industry, we suggest here a disease modelling framework designed to better understand human asthma, and accelerate the development of safe and efficacious new asthma drugs that go beyond symptomatic relief.