In the single-arm phase of the trial, 124 high-risk NB pts were enrolled for the treatment with 6 × 106 IU/m2/d s.c. IL-2 (d1–5), followed by a combined application of IL-2 (d8–12) with LTI of ch14.18/CHO (10 × 10 mg/m2/d; d8–18). Here, IL2 is linked to neuroblastoma.