A pilot study of chemoimmunotherapy in the postconsolidation setting for high‐risk neuroblastoma (ANBL19P1): A report from the Children’s Oncology Group

Abstract Background Survival for patients with high‐risk neuroblastoma remains poor despite current‐era multimodality treatment that includes postconsolidation GD2‐directed immunotherapy. Given the promising responses in patients who receive dinutuximab‐based chemoimmunotherapy in the relapsed setting, the Children’s Oncology Group ANBL19P1 study evaluated the feasibility of administering irinotecan, temozolomide, dinutuximab, and sargramostim after frontline consolidation with tandem autologous stem cell transplantation (ASCT). Methods Patients with high‐risk neuroblastoma who received induction therapy followed by tandem ASCT and had no evidence of progressive disease (PD) were eligible. Treatment included five 28‐day cycles of temozolomide and irinotecan (days 1–5), dinutuximab (days 2–5), and sargramostim (days 6–12). Isotretinoin (days 8–21) was given during cycles 1–6. Therapy was deemed feasible if the 95% confidence interval placed on the percentage of patients that completed five cycles of chemoimmunotherapy without PD within 30 weeks contained 75% in the absence of excessive toxicity. Event‐free survival and overall survival were determined from the time of enrollment. Results Forty eligible patients enrolled, and 35 (87.5%; 95% confidence interval, 73.9%–94.5%) completed five cycles without PD within 30 weeks, meeting the feasibility threshold. No unacceptable toxicities occurred on protocol therapy, including no toxic deaths. Five patients discontinued therapy early because of physician determination ( n = 2), patient/parent refusal of further therapy ( n = 2), and PD ( n = 1). The 2‐year event‐free and overall survival rates were 82.5% ± 6.1% and 92.5% ± 4.2%, respectively. Conclusions The administration of chemoimmunotherapy in the postconsolidation setting after tandem ASCT is feasible and tolerable. Future studies will be needed to define the population most likely to benefit from this augmented postconsolidation therapy.