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.