Omalizumab in the treatment of adult patients with mastocytosis: A systematic review

Abstract

Background Mastocytosis is associated with mast cell (MC) mediator‐related symptoms for which limited therapies are available. Objective Our aim was to assess the efficacy and safety of omalizumab in the treatment of MC mediator‐related symptoms in adult patients with mastocytosis. Results We identified one multi‐centre retrospective cohort study (39 patients), one retrospective cohort study (13 patients), 4 case series and 10 case reports. No published controlled randomized study was identified. We included 69 patients (13 patients with cutaneous mastocytosis and 56 with systemic mastocytosis). The mean age was 48 years. Omalizumab maintenance dose was 300 mg for the majority of patients. The mean duration of treatment was 17 months. Treatment led to a tolerability of venom immunotherapy and to a complete resolution of severe reactions in all patients with post‐honeybee sting anaphylaxis. Complete resolution of idiopathic anaphylaxis episodes was noted in 84% of the patients. Complete resolution of palpitations, gastrointestinal, cutaneous, neuropsychiatric, respiratory and musculoskeletal symptoms was observed at a rate of 43%, 29%, 27%, 11%, 9% and 0%, respectively. Efficacy was maintained for the entire duration of the treatment in all but four responders. Adverse events were reported for 13 patients. Conclusions and Clinical Relevance Omalizumab appears to prevent some life‐threatening reactions associated with mastocytosis and may be a good option to treat the associated symptoms. However, the evidence relied upon is observational, uncontrolled and from a small number of patients. A randomized controlled trial is needed to better understand the place of omalizumab in mastocytosis treatment.

Mediator-Related Symptoms and Anaphylaxis in Children with Mastocytosis

“…Recently, omalizumab has been proposed for mastocytosis patients to treat severe mediator-related symptoms and to prevent anaphylaxis (3,(91)(92)(93)(94)(95)(96)(97)(98)(99)(100)(101). The drug was indeed found to be effective in the prevention of recurrent episodes of idiopathic anaphylaxis in adults with mastocytosis (91)(92)(93)(94)(95)(96)(97)(98)(99)(100)(101), but has only be licensed for use in children over 12 years of age. The results of the XOLMA study has shown that omalizumab was safe and improved mastocytosis symptoms like diarrhea, dizziness, flush and anaphylactic reactions (100).…”

Risk and management of patients with mastocytosis and MCAS in the SARS-CoV-2 (COVID-19) pandemic: Expert opinions

“…Patients with MCAS suffering from recurrent anaphylactic events due to IgE-dependent venom allergy are advised to undergo venom immunotherapy and/or are treated with anti-IgE antibodies (omalizumab) along with precautions to avoid the allergen. [34][35][36] The most dangerous form of MCAS is the mixed variant (primary plus secondary), where both clonal MC (6an MC neoplasm) and an IgE-dependent allergy are found. 36 These patients are at high risk to develop a fatal MCAS event.…”

Mast cells as a unique hematopoietic lineage and cell system: From Paul Ehrlich's visions to precision medicine concepts

“…The clinical efficacy of many of these agents is currently being explored in clinical trials. Finally, for patients with severe allergies and MCAS, and for those who are suffering from severe allergies, MCAS and/or additional aggravating MC conditions (like HAT and/or mastocytosis), application of antibodies removing IgE, such as omalizumab or ligelizumab, or targeting MC tryptase, may represent promising additional approaches 310 - 314 . Finally, a number of inhibitory receptors, such as Siglec-7, Siglec-8, or CD300a, have been identified on human MCs and are currently being validated for their role as therapeutic target sites 315 - 318 .…”