- Reduce intensity of therapy for patients 365 to < 547 days (12-18 months) of age with stage 3 MYCN-nonamplified but unfavorable histology neuroblastoma and maintain a 3-year EFS rate consistent with that for patients < 1 year of age with stage 3, MYCN-nonamplified, unfavorable histology neuroblastoma treated on COG-A3961.