2020) One of these trials (NCT03126916) also includes an arm for patients with anaplastic lymphoma kinase (ALK) mutations whose treatment will include the tyrosine kinase inhibitor (TKI) crizotinib, which has previously shown modest success in HRNB patients with ALK mutations

2020) One of these trials (NCT03126916) also includes an arm for patients with anaplastic lymphoma kinase (ALK) mutations whose treatment will include the tyrosine kinase inhibitor (TKI) crizotinib, which has previously shown modest success in HRNB patients with ALK mutations.(Foster, Voss et al. antibodies (SADA) == Introduction == The 5-12 months survival rate of high-risk neuroblastoma (HRNB) has been driven above 50% with the addition of GD2-targeting monoclonal antibodies (mAbs) to multimodal treatment.(Yu, Gilman et al. 2010,Cheung, Cheung et al. 2012) Patients with HRNB are typically treated in three phases: 1) Induction: chemotherapy (usually a combination of platinum-based drugs, alkylating brokers, and topoisomerase inhibitors), stem cell collection (peripheral or from bone marrow), and surgery to resect the primary tumor, 2) Consolidation: high-dose Pralidoxime Iodide chemotherapy followed by autologous stem cell transplant (ASCT) and radiation therapy to eliminate residual disease, and 3) Maintenance: anti-GD2 mAb-based immunotherapy with interleukin-2 (IL-2), granulocyte-macrophage colony-stimulating factor (GM-CSF), and isotretinoin to prevent relapse.(Smith and Foster 2018) More recent updates have disproven the need for IL-2(Ladenstein, Potschger Pralidoxime Iodide et al. 2018) or isotretinoin.(Matthay, Reynolds et al. 2009. Errata, J Clin Oncol 32:1862-1863, 2014.) Despite this aggressive treatment strategy, close to half of patients still relapse and succumb to their disease. Efforts are ongoing to improve outcomes during all three phases of treatment and to develop new strategies capable of effectively treating relapsed disease. Among these experimental treatments is usually131I-metaiodobenzylguanidine (MIBG), a radionuclide-conjugated norepinephrine analog selectively taken up by cells expressing the norepinephrine transporter and organic cation transporters (OCT),(Lpez Quiones, Wagner et al. 2020) including neuroblastoma cells. Due to this selectivity,123I-MIBG is considered the gold standard imaging agent for HRNB.(Pandit-Taskar and Modak 2017) Treatment with131I-MIBG has resulted in complete and partial responses in some HRNB patients and remains under investigation (NCT03126916,NCT03561259,NCT03332667NCT01850888).(Mastrangelo, Rufini et al. 2011,Villablanca, Maris et al. 2020) One of these trials (NCT03126916) also includes an arm for patients with anaplastic lymphoma kinase (ALK) mutations whose treatment will include the tyrosine kinase inhibitor (TKI) crizotinib, which has previously shown modest success in HRNB patients with ALK mutations.(Foster, Voss et al. 2021) Another radiopharmaceutical treatment being developed is usually131I-8H9 (Omburtamab), a radiolabeled monoclonal antibody targeting B7 homolog 3 (B7-H3) delivered via Ommaya reservoir to target central nervous system (CNS) and leptomeningeal tumors (NCT00089245,NCT03275402). Other investigational treatments administered during the maintenance phase to prevent relapse include a GD2/GD3 ganglioside vaccine, which was shown to be safe and tolerable in a Phase I trial(Kushner, Cheung et al. 2014) and has since completed a Phase II in 102 patients (NCT04936529).(Cheung, Cheung et al. 2021) Anti-GD2 immunoglobulin G (IgG) 1 seroconversion was associated with continuous progression free survival and Pralidoxime Iodide overall CFD1 survival in a multivariable analysis, and strongly correlated with dectin-1 single nucleotide polymorphism. Remarkably, despite the anti-GD2 titer, there were no pain or Pralidoxime Iodide neuropathy side effects. Difluoromethylornithine (DFMO), an ornithine decarboxylase inhibitor, when added to patients in remission following anti-GD2 immunotherapy was safe, with favorable event-free survival (EFS) and overall survival (OS) compared to historical controls.(Lewis, Kraveka et al. 2020) Other researchers are screening GD2-specific chimeric antigen receptor (CAR) T cells, which have been shown to be safe, though only moderately effective.(Straathof, Flutter et al. 2020) Given that potential on-target, off-tumor toxicity against neural cells expressing GD2 was a major security concern and studies have shown this not to be an issue, research efforts are ongoing in an effort to increase efficacy, possibly by combining CAR T cells with other brokers, including immune checkpoint inhibitors.(Heczey, Louis et al. 2017) CAR T cells targeting L1 cell adhesion molecule (L1CAM), another tumor-associated antigen expressed by neuroblastoma tumors, have also been confirmed Pralidoxime Iodide safe in Phase I trials, but with even fewer responses than GD2-CAR T cells.(Park, Digiusto et al. 2007,Richards, Sotillo et al. 2018) Another type of immunotherapy under investigation for treatment of HRNB is usually bispecific antibodies (BsAbs), which have been successfully implemented to treat hematological cancers and are in various stages of development for solid tumors.(Velasquez, Bonifant et al. 2018) BsAbs are engineered to possess specificity for two antigens; in the case of BsAbs used in malignancy therapy one of these antigens is usually a tumor-associated antigen and the other is an immune cell receptor, usually CD3 on T cells. This design allows the BsAbs to serve as a bridge between polyclonal immune cells and tumor cells, inducing a synthetic immune response against the tumors. Although neuroblastoma, like many.