- Yu, Alice L;
- Gilman, Andrew L;
- Ozkaynak, M Fevzi;
- Naranjo, Arlene;
- Diccianni, Mitchell B;
- Gan, Jacek;
- Hank, Jacquelyn A;
- Batova, Ayse;
- London, Wendy B;
- Tenney, Sheena C;
- Smith, Malcolm;
- Shulkin, Barry L;
- Parisi, Marguerite;
- Matthay, Katherine K;
- Cohn, Susan L;
- Maris, John M;
- Bagatell, Rochelle;
- Park, Julie R;
- Sondel, Paul M
Purpose
Previously our randomized phase III trial demonstrated that immunotherapy including dinutuximab, a chimeric anti-GD2 mAb, GM-CSF, and IL2 improved survival for children with high-risk neuroblastoma that had responded to induction and consolidation therapy. These results served as the basis for FDA approval of dinutuximab. We now present long-term follow-up results and evaluation of predictive biomarkers.Patients and methods
Patients recieved six cycles of isotretinoin with or without five cycles of immunotherapy which consists of dinutuximab with GM-CSF alternating with IL2. Accrual was discontinued early due to meeting the protocol-defined stopping rule for efficacy, as assessed by 2-year event-free survival (EFS). Plasma levels of dinutuximab, soluble IL2 receptor (sIL2R), and human anti-chimeric antibody (HACA) were assessed by ELISA. Fcγ receptor 2A and 3A genotypes were determined by PCR and direct sequencing.Results
For 226 eligible randomized patients, 5-year EFS was 56.6 ± 4.7% for patients randomized to immunotherapy (n = 114) versus 46.1 ± 5.1% for those randomized to isotretinoin only (n = 112; P = 0.042). Five-year overall survival (OS) was 73.2 ± 4.2% versus 56.6 ± 5.1% for immunotherapy and isotretinoin only patients, respectively (P = 0.045). Thirteen of 122 patients receiving dinutuximab developed HACA. Plasma levels of dinutuximab, HACA, and sIL2R did not correlate with EFS/OS, or clinically significant toxicity. Fcγ receptor 2A and 3A genotypes did not correlate with EFS/OS.Conclusions
Immunotherapy with dinutuximab improved outcome for patients with high-risk neuroblastoma. Early stoppage for efficacy resulted in a smaller sample size than originally planned, yet clinically significant long-term differences in survival were observed.