Personalized management strategies in mast cell disorders: ECNM-AIM User's guide for daily clinical practice

Mastocytosis is a myeloid neoplasm defined by expansion and focal accumulation of clonal mast cells (MCs) in one or more organs. The disease exhibits a complex pathology and may be complicated by MC activation, bone abnormalities, neurological problems, gastrointestinal symptoms, and/or hematologic progression. The World Health Organization divides mastocytosis into cutaneous forms, systemic mastocytosis (SM) and MC sarcoma. In most patients with SM, somatic mutations in KIT are detected. Patients with indolent SM have a normal to near-normal life expectancy, whereas patients with advanced SM, including aggressive SM and MC leukemia, have a poor prognosis. In those with advanced SM, multiple somatic mutations and an associated hematologic neoplasm may be detected. Mediator-related symptoms can occur in any type of mastocytosis. Symptoms may be mild, severe, or even life-threatening. In patients with severe acute symptoms, an MC activation syndrome may be diagnosed. In these patients, relevant comorbidities include IgE-dependent and IgE-independent allergies. Management of patients with SM is an emerging challenge in daily practice and requires in-depth knowledge and a multidisciplinary and personalized approach with selection of appropriate procedures and interventions. In this article, we review the current knowledge on SM and MC activation syndrome, with emphasis on multidisciplinary aspects in diagnosis and patient-specific management. In addition, we provide a user’s guide for application of markers, algorithms, prognostic scores, and treatments for use in daily practice.This work was supported in part by the Austrian Science Fund (FWF; projects F4704 and P32470-B to P.V.) and the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH) (to M.C.C. and D.D.M.). The content is solely the responsibility of the authors and does not represent the official views of the NIH

Efficacy and safety of avapritinib in advanced systemic mastocytosis:interim analysis of the phase 2 PATHFINDER trial

Advanced systemic mastocytosis (AdvSM) is a rare, KIT D816V-driven hematologic neoplasm characterized by mast cell infiltration and shortened survival. We report the results of a prespecified interim analysis of an ongoing pivotal single-arm phase 2 trial (no. NCT03580655) of avapritinib, a potent, selective KIT D816V inhibitor administered primarily at a once-daily starting dose of 200 mg in patients with AdvSM (n = 62). The primary endpoint was overall response rate (ORR). Secondary endpoints included mean baseline change in AdvSM–Symptom Assessment Form Total Symptom Score and quality of life, time to response, duration of response, progression-free survival, overall survival, changes in measures of disease burden and safety. The primary endpoint was successfully met (P = 1.6 × 10(-9)), with an ORR of 75% (95% confidence interval 57–89) in 32 response-evaluable patients with AdvSM who had sufficient follow-up for response assessment, including 19% with complete remission with full or partial hematologic recovery. Reductions of ≥50% from baseline in serum tryptase (93%), bone marrow mast cells (88%) and KIT D816V variant allele fraction (60%) were observed. The most frequent grade ≥3 adverse events were neutropenia (24%), thrombocytopenia (16%) and anemia (16%). Avapritinib demonstrated a high rate of clinical, morphological and molecular responses and was generally well tolerated in patients with AdvSM

Proceedings from the Inaugural American Initiative in Mast Cell Diseases (AIM) Investigator Conference

The American Initiative in Mast Cell Diseases (AIM) held its inaugural investigator conference at Stanford University School of Medicine in May 2019. The overarching goal of this meeting was to establish a Pan-American organization of physicians and scientists with multidisciplinary expertise in mast cell disease. To serve this unmet need, AIM envisions a network where basic, translational, and clinical researchers could establish collaborations with both academia and biopharma to support the development of new diagnostic methods, enhanced understanding of the biology of mast cells in human health and disease, and the testing of novel therapies. In these AIM proceedings, we highlight selected topics relevant to mast cell biology and provide updates regarding the recently described hereditary alpha-tryptasemia. In addition, we discuss the evaluation and treatment of mast cell activation (syndromes), allergy and anaphylaxis in mast cell disorders, and the clinical and biologic heterogeneity of the more indolent forms of mastocytosis. Because mast cell disorders are relatively rare, AIM hopes to achieve a coordination of scientific efforts not only in the Americas but also in Europe by collaborating with the well-established European Competence Network on Mastocytosis.The research reported in this publication was supported by the National Center for Advancing Translational Sciences of the National Institutes of Health (NIH) (award no. R13TR002722 to J.G.). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. We thank The Mast Cell Disease Society, Inc (TMS), a national 501c3 nonprofit, for their partnership and support of AIM, for patient-centered research, and for sponsoring international physicians at this inaugural meeting. J.G. expresses gratitude for the support of the Charles and Ann Johnson Foundation, the staff of the Stanford Mastocytosis Center, and the Stanford Cancer Institute Innovation Fund. M.C., J.J.L., and D.D.M. are supported in part by the Division of Intramural Research of the National Institute of Allergy and Infectious Diseases, NIH. D.F.D. is supported by the Asthma and Allergic Diseases Cooperative Research Centers Opportunity Fund (award no. U19AI07053 from the NIH). P.V. has been supported by the Austrian Science Fund (FWF) (grant nos. F4701-B20, F4704-B20, and P32470-B)

Mast Cell Diseases in Practice and Research: Issues and Perspectives Raised by Patients and Their Recommendations to the Scientific Community and Beyond

Background: Since 2010, patients and physicians have collaborated to understand unmet needs of patients with mast cell diseases, incorporating mastocytosis and mast cell activation disorders, which include mast cell activation syndromes. Objective: This Open Innovation in Science project aims to expand understanding of the needs of patients affected by mast cell diseases, and encourage global communication among patient advocacy groups, physicians, researchers, industry, and government. A major aim is to support the scientific community's efforts to improve diagnosis, management, therapy, and patients’ quality of life by addressing unmet needs. Methods: In collaboration with mast cell disease specialists, 13 patient advocacy groups from 12 countries and regions developed lists of top patient needs. A core team of leaders from patient advocacy groups collected and analyzed the data and proposed possible actions to address patient needs. Results: Findings identified similarities and differences among participating countries in unmet needs between patients with mastocytosis and those with mast cell activation syndromes. Issues emphasized struggles relating to the nature and rarity of mast cell diseases, their impact on quality of life, the diagnostic process, access to appropriate care, more effective treatment, and the need for research. Conclusions: Solutions vary across countries because situations differ, in particular regarding the existence of and access to centers of excellence and reference centers. Multifaceted mast cell activation syndrome barriers necessitate innovative approaches to improve access to appropriate care. The outcomes of this project should greatly support scientists and clinicians in their efforts to improve diagnosis, management, and treatment of patients with mastocytosis and mast cell activation disorders.The authors thank Tania Bray, Jan Hempstead, Heather Mayne, Joanne Mulder-Brambleby, and Irene Wilson for their supporting contributions, and all patients and families affected by MCDs, who shared their needs and concerns for development of this project. Authors involved in study conception and design were P. Valent, S.V. Jennings, C.C. Finnerty, J.S. Hobart, M. Martín-Martínez, K.A. Sinclair, V.M. Slee, J. Agopian, C. Akin, I. Álvarez-Twose, P. Bonadonna, A.A. Bowman, K. Brockow, H. Bumbea, C. de Haro, J.S. Fok, K. Hartmann, N. Hegmann, O. Hermine, M. Kalisiak, C.H. Katelaris, J. Kurz, P. Marcis, D. Mayne, D. Mendoza, A. Moussy, G. Mudretzkyj, N. Nidelea Vaia, M. Niedoszytko, H. Oude Elberink, A. Orfao, D.H. Radia, S. Rosenmeier, E. Ribada, W. Schinhofen, J. Schwaab, F. Siebenhaar, M. Triggiani, G. Tripodo, R. Velazquez, Y. Wielink, F. Wimazal, T. Yigit, and C. Zubrinich. Authors involved in acquisition and review of data were S.V. Jennings, C.C. Finnerty, J.S. Hobart, M. Martín-Martínez, K.A. Sinclair, V.M. Slee, J. Agopian, C. Akin, I. Álvarez-Twose, P. Bonadonna, A.A. Bowman, K. Brockow, H. Bumbea, C. de Haro, J.S. Fok, K. Hartmann, N. Hegmann, O. Hermine, M. Kalisiak, C.H. Katelaris, J. Kurz, P. Marcis, D. Mayne, D. Mendoza, A. Moussy, G. Mudretzkyj, N. Nidelea Vaia, M. Niedoszytko, H. Oude Elberink, A. Orfao, D.H. Radia, S. Rosenmeier, E. Ribada, W. Schinhofen, J. Schwaab, F. Siebenhaar, M. Triggiani, G. Tripodo, R. Velazquez, Y. Wielink, F. Wimazal, T. Yigit, C. Zubrinich, and P. Valent. The Core Group (analysis and interpretation of data and drafting of the manuscript) include S.V. Jennings, C.C. Finnerty, J.S. Hobart, M. Martín-Martínez, K.A. Sinclair, and V.M. Slee. Critical revision was performed by S.V. Jennings, C.C. Finnerty, J.S. Hobart, M. Martín-Martínez, K.A. Sinclair, V.M. Slee, J. Agopian, C. Akin, I. Álvarez-Twose, P. Bonadonna, A.A. Bowman, K. Brockow, H. Bumbea, C. de Haro, J.S. Fok, K. Hartmann, N. Hegmann, O. Hermine, M. Kalisiak, C.H. Katelaris, J. Kurz, P. Marcis, D. Mayne, D. Mendoza, A. Moussy, G. Mudretzkyj, N. Nidelea Vaia, M. Niedoszytko, H. Oude Elberink, A. Orfao, D.H. Radia, S. Rosenmeier, E. Ribada, W. Schinhofen, J. Schwaab, F. Siebenhaar, M. Triggiani, G. Tripodo, R. Velazquez, Y. Wielink, F Wimazal, T. Yigit, C. Zubrinich, and P. Valent

Mast Cell Diseases in Practice and Research:Issues and Perspectives Raised by Patients and Their Recommendations to the Scientific Community and Beyond

Background: Since 2010, patients and physicians have collaborated to understand unmet needs of patients with mast cell diseases, incorporating mastocytosis and mast cell activation disorders, which include mast cell activation syndromes. Objective: This Open Innovation in Science project aims to expand understanding of the needs of patients affected by mast cell diseases, and encourage global communication among patient advocacy groups, physicians, researchers, industry, and government. A major aim is to support the scientific community's efforts to improve diagnosis, management, therapy, and patients’ quality of life by addressing unmet needs. Methods: In collaboration with mast cell disease specialists, 13 patient advocacy groups from 12 countries and regions developed lists of top patient needs. A core team of leaders from patient advocacy groups collected and analyzed the data and proposed possible actions to address patient needs. Results: Findings identified similarities and differences among participating countries in unmet needs between patients with mastocytosis and those with mast cell activation syndromes. Issues emphasized struggles relating to the nature and rarity of mast cell diseases, their impact on quality of life, the diagnostic process, access to appropriate care, more effective treatment, and the need for research. Conclusions: Solutions vary across countries because situations differ, in particular regarding the existence of and access to centers of excellence and reference centers. Multifaceted mast cell activation syndrome barriers necessitate innovative approaches to improve access to appropriate care. The outcomes of this project should greatly support scientists and clinicians in their efforts to improve diagnosis, management, and treatment of patients with mastocytosis and mast cell activation disorders

Ruxolitinib: evolution or revolution in treatment of patients with polycythemia vera?

Current treatments for polycythemia vera have remained unchanged for decades with phlebotomy, hydroxycarbamide (also named hydroxyurea) and to a lesser extent interferon being the cornerstones in our therapeutic armamentarium. However, some patients do not respond to, or indeed experience significant side effects to, these current agents and development of alternative therapeutic options is required. Ruxolitinib, a potent JAK1/2 inhibitor, initially approved for myelofibrosis, was recently approved for patients with polycythemia vera refractory or intolerant to hydroxycarbamide. In this article, we review the currently available efficacy and safety data