The safety of self‐administered allergen immunotherapy during the buildup and maintenance phases

Abstract

Background Self-administered allergen immunotherapy is considered controversial. We believe the implementation of a self-administration protocol characterized by patient preselection and a slow buildup phase is safe. Methods We analyzed 23,614 patient records and associated immunotherapy injections for systemic reactions (SR) during a 1-year period (2011 to 2012). SRs were graded in accordance with the World Allergy Organization (WAO) criteria. Results Thirty-seven SRs were reported for 23,614 patients who self-administered 2,021,600 injections yielding an annual SR rate of 0.16% (per patient) or 0.002% (per injection). Only 9 of 4643 pediatric (0.19%) and 28 of 18,971 adult patients (0.15%) experienced 1 or more SRs. No deaths (grade V SR) occurred. From 2009 through early 2014, over 90,000 patients received more than 10 million injections in accordance with the United Allergy Services (UAS) protocol without fatalities. Conclusion We believe this safety profile is due to a preselection of patients to exclude those with a high risk for adverse reactions and a slow immunotherapy buildup phase. In contrast, previous studies documented office-based SRs ranging from approximately 3% to greater than 14%. Thus, the UAS home-immunotherapy SR rate is significantly lower than office-based immunotherapy SR rates (p < 0.0001). The enhanced safety of this protocol results in a decreased frequency and severity of SRs. This safety report, derived from analyses of one of the largest patient cohorts studied, corroborates and expands the observations of previous studies of self-administered subcutaneous immunotherapy in a low-risk patient population by assessing self-administered allergen immunotherapy during the buildup and maintenance phases.

The efficacy assessment of a self‐administered immunotherapy protocol

“…The systemic reaction rate was only 0.16% per individual and 0.002% per injection in comparison to significantly higher office-based rates of approximately 4% to 14%. 12 Consistent with these results, several other reports have previously documented the safety of self-administered or home-based SCIT. 13–17 The authors concluded that the low systemic reaction rates reported showed that home-based immunotherapy was safe.…”

“…12 The rate of allergen dose increase during the buildup phase is considered a prominent factor in immunotherapy-based systemic reactions. 9,65–67 Consistent with these principles, the UAS protocol was designed to incorporate a slow buildup phase in order to diminish the associated high frequency of systemic reactions.…”

“…Also, based upon the administration frequency and allergen concentrations used, cumulative allergen dosing is equivalent to current recommendations. 2,12 A more detailed description of the UAS SCIT protocol has been recently published. 12 …”

“…12–17 A recent criticism hypothesized that 1 set of these safety outcomes was achieved by utilizing subtherapeutic allergen concentrations and thus, the attainment of clinical efficacy was questioned. 18 Therefore, the demonstration of clinical efficacy is a salient issue, particularly for self-administered SCIT protocols.…”

Safety of subcutaneous allergen immunotherapy in children: A retrospective review and bird eye to literature

“…13,23,28 In a study involving 23,610 children and adult patients under immunotherapy, side effects have been shown to be more common in female gender and older ages. 29 There was no significant difference regarding the age group in our study, however side-effects were significantly more common in the female gender.…”