CD22 and graft versus host disease: Similar trials utilizing TALEN-based TRAC KO, including CD19-targeting ALLO-501 (NCT03939026), ALLO-501A (NCT04416984), and UCART19 (NCT02746952), BCMA-targeting ALLO-715 (NCT04093596), and CD22-targeting UCART22 (NCT04150497), reported either no GvHD or GvHD in a small fraction of patients (no more than 8% with grade 1 acute skin GvHD) [67–69, 138, 139].