Safety of Two Cluster Schedules for Subcutaneous Immunotherapy in Allergic Rhinitis or Asthma Patients Sensitized to Inhalant Allergens

Abstract

Background: Subcutaneous immunotherapy (SCIT) usually requires a long titration phase, which can be associated with various adverse events (AEs). Objectives: It was the aim of this study to determine the safety of 2 cluster regimens for SCIT in patients with allergic rhinitis, with or without mild or moderate allergic asthma, who were sensitized to grass and/or tree pollen, or house dust mites (HDM). Patients and Methods: Adult patients were included in a European, open-label, prospective trial. Pollen-allergic patients received grass pollen, grass and olive pollen, or hazel, alder and birch pollen according to a 3-week titration cluster. HDM-allergic patients received HDM extract according to a 2-week titration cluster. The safety of the titration phase was assessed in terms of local and systemic AEs. Results: The safety analysis included 157 patients: 110 received pollen and 47 HDM extract. During the cluster titration, 248 AE episodes were reported in the pollen group and 113 in the HDM group; these were mainly local reactions. Around one third of patients (30.9% pollen and 38.3% HDM) did not experience any AE. In most cases (67.1% of pollen and 71.1% of HDM patients), AEs did not lead to a change in titration schedule. No anaphylactic reaction or other serious life-threatening systemic AEs were reported. Only 2 patients in the HDM group discontinued treatment because of AEs. Conclusions: Rapid cluster titration was well tolerated in adults with allergic rhinitis, with or without mild to moderate allergic asthma, due to pollen or HDM. This short-titration, high-dose cluster regime may allow better patient compliance and cost savings.

Accelerated Up-Dosing of Subcutaneous Immunotherapy with a Registered Allergoid Grass Pollen Preparation

“…Accelerated schedules of allergen-specific immunotherapy such as ‘rush’ or ‘cluster’ protocols aim to achieve the maintenance dose of immunotherapy more rapidly than conventional schedules. The safety of accelerated protocols has been shown in previous studies evaluating SCIT [6,7,8,9,10,11,12]. In addition, accelerated up-dosing may induce clinical and immunologic improvements sooner [10,11,12].…”

Cluster Subcutaneous Allergen Specific Immunotherapy for the Treatment of Allergic Rhinitis: A Systematic Review and Meta-Analysis

“…The remaining 24 full-text articles were reviewed for more detailed evaluation; 15 of them were also excluded. Of them, 4 studies were not real randomized/controlled studies [13]–[16], 10 studies in which some patients included were asthmatics alone without AR [17]–[26], and 1 study did not perform a real cluster protocol [27]. Additional, a RCT was excluded due to repeated data [28].…”

Chinese Guideline on allergen immunotherapy for allergic rhinitis

“…The protocols of cluster AIT have been investigated in several clinical trials using chemically modified allergen extracts (179,(196)(197)(198)(199). Compared to the normal build-up phase of around 4 months in conventional AIT, the build-up dosing phase in cluster AIT lasts between 6 to 8 weeks, and is followed by a dose-maintenance phase ( Table 4).…”