The utility of intravenous immunoglobulin infection prophylaxis in patients on anti-CD38 therapies

Background Anti-CD38 directed therapies have emerged as targeted treatments for multiple myeloma (MM) and light chain (AL) amyloidosis. Intravenous immunoglobulin (IVIG) supplementation has been shown to reduce the risk of bacterial infections by 39% in patients with MM receiving anti-CD38 therapies, with a 72% reduction in grade 3–4 infections. However, there is currently no universal guidance on the optimal population in whom to initiate IVIG prophylaxis to prevent these infectious complications. Methods This study was a retrospective, single-centered chart review of eligible patients treated at Yale New Haven Health System (YNHHS) from 2016–2022. Eligible patients included adults with MM or AL amyloidosis treated with an anti-CD38 based regimen. The primary outcome was to compare the rate of pneumonia in patients who have received IVIG as compared to patients who have not. The secondary outcome was to identify the immunoglobulin G (IgG) level associated with an increased risk of pneumonia. Results Rates of pneumonia were found to be higher within the population receiving IVIG as compared to those not receiving IVIG (29.55% vs. 15.41%, p = 0.05). There were no significant differences in the subgroup analyses including line of therapy, anti-CD38 agent, diagnosis, and IgG disease involvement. There was also no significant correlation demonstrated between baseline IgG level and the occurrence of pneumonia (β1 −0.0001, p = 0.37). Conclusions IVIG supplementation in patients receiving anti-CD38 directed therapy did not significantly reduce the incidence of pneumonia. Given the lack of benefit with IVIG supplementation, careful consideration must be given prior to administration to limit unnecessary utilization.