Safety and Tolerability of Home Infusions in Down Syndrome Regression Disorder.

Purpose: Down syndrome regression disorder (DSRD) is a rare neuropsychiatric condition affecting otherwise healthy individuals with Down syndrome. Multiple studies on DSRD have revealed that immunotherapy with intravenous immunoglobulin (IVIg) is both safe and effective, although site of infusion has never been studied. This study sought to evaluate the safety and tolerability of IVIg in individuals with DSRD receiving home-based infusions.

Methods: A single-center, retrospective chart review evaluating infusion reactions was performed for individuals meeting criteria for DSRD and having received IVIg infusions between 2019 and 2024. Adverse events (AEs) were evaluated for severity and need for alterations in infusion plan. A cohort of individuals receiving home-based infusions was compared with a cohort of individuals receiving infusions at an academic medical center.

Findings: A total of 315 individuals (162 institutional infusions [51%] and 153 home infusions [49%]) met the inclusion criteria. There were no statistical differences between the demographic and clinical features of the cohorts. Individuals receiving home infusions had the same rate of AE during an infusion (P = 0.14), although they did have a lower number of total AEs (P < 0.001). Individuals receiving home infusions experienced a lower number of behavioral issues with infusions (P = 0.03) and had significantly lower discontinuations of infusions secondary to behavioral issues (P = 0.04).

Implications: Rates of AEs and serious AEs in those with DSRD were the same regardless of site of infusion. These data should be considered in policy regarding the appropriateness of home-based infusions as a safe alternative, when suitable for patients and caregivers, for individuals with DSRD.