Comparison of Standard, Cluster, and Rush Allergy Immunotherapy Buildup Protocols

Abstract

Background: Allergy immunotherapy (AIT) involves a dose-escalation phase following 1 of 3 protocols: standard, cluster, or rush. Although the cluster and rush protocols have been shown to decrease the time to reach maintenance dosing, there is a lack of direct comparison between the protocols.

Objective: This study aimed to evaluate the differences in time to maintenance dosing and occurrence of adverse reactions among the dose-escalation protocols.

Methods: A retrospective observation study of patients on AIT was conducted. Patients were categorized as participating in the standard, cluster, or rush buildup protocols. Patients on the rush protocol, unlike the standard and cluster protocols, were required to receive prednisone, montelukast, cetirizine, and famotidine on the rush day and first 2 weekly injections thereafter. Variables analyzed include patient demographics, time until maintenance dosing, rate of adverse reactions, treatments required for reactions, and AIT formulation.

Results: Data were reviewed on 237 patients on the standard (n = 41), cluster (n = 122), and rush (n = 74) protocols. The maintenance dose was achieved faster with the rush (16.50 weeks) and cluster (19.33 weeks) buildup protocols than the standard (31.09 weeks) protocol (P < .001). There was no statistically significant difference between time to maintenance dosing when comparing the cluster and rush protocols (P = .322). Despite pretreatment with the rush protocol, the rate of systemic reactions was the same for the standard (9.76%), cluster (9.84%), or rush (14.86%) buildup protocols (P = .526).

Conclusion: Patients on the cluster buildup protocol for AIT achieved maintenance dosing in a comparable time frame as the rush protocol with a similar rate of systemic reactions and without the need for the pretreatment required with rush immunotherapy.

Keywords: Adverse reactions; Allergy immunotherapy; Buildup; Cluster; Rush.