Retrospective Crossover of Patients with Primary Immunodeficiency Switching from Standard Immune Globulin Replacement Therapy to ASCENIV

ASCENIV is a 10% intravenous immune globulin (IVIG) indicated for the treatment of primary humoral immunodeficiency (PI) in adults and adolescents (12 to 17 years of age). ASCENIV contains a blend of normal source plasma and plasma containing high antibody titers to respiratory syncytial virus (RSV). In the phase 3 trial, 59 PI patients were treated with ASCENIV 300–800 mg/kg every 3 or 4 weeks for 12 months. The study resulted in zero acute serious bacterial infections, meeting the primary endpoint. Since the approval, case reports have described select clinical cases of patients with PI who have switched from standard immune globulin (IG) to ASCENIV due to recurrent respiratory infections and experienced fewer infections. The goal of this retrospective crossover was to investigate the changes in infections in patients with PI who transitioned from a previous IG product to ASCENIV. Data were collected from de-identified medical records through Soleo Health using SoleMetrics from January 1, 2020, to December 31, 2024. Patients were included if they received ASCENIV for the treatment of PI for a minimum of 120 assessment days and received a different IG replacement therapy from the same specialty pharmacy prior to transitioning to ASCENIV. Medical records included data on reported infections from telephonic visits from the pharmacy care team or nursing visits for IG administration. The number of infections on previous IG products compared to the number of infections on ASCENIV was analyzed using Poisson regression. Fourteen patients were included in the data collection. Patients were primarily female (n = 10, 83.3%) with an average age of 69.9 years. During the observation period on the previous IG product, a mean of 3.4 infections occurred (standard deviation [SD]: 3.94), whereas during the observation period of patients on ASCENIV, 1.2 infections occurred (SD: 0.89; p = 0.0169). IG product selection should be individualized for each patient’s clinical needs and comorbidities. This study suggests that ASCENIV may reduce infections in patients with PI who experience infections despite IG therapy. Larger, prospective studies are needed to confirm these results and further understand the select patient population that may benefit from ASCENIV.