The side effects included respiratory infections (14%), with 1 case of SARS-COV-2 pneumonia, one case of herpes zoster infection, one case of cytomegalovirus colitis, one severe infusional reaction, IgG and/or IgM hypogammaglobulinemia (18%), and transient mild-moderate neutropenia (7%). Here, CD40LG is linked to neutropenia.