anti-GD2 Antibody Ch14 Research Articles

A Multi-Color Flow Cytometric Assay for Quantifying Dinutuximab Binding to Neuroblastoma Cells in Tumor, Bone Marrow, and Blood.

GD2, a disialoganglioside, is present on the surface of most neuroblastomas, as well as on some other cancers, such as melanoma and osteogenic sarcoma. The anti-GD2 antibody ch14.18 (dinutuximab) has an FDA-registered indication for use as maintenance therapy for high-risk neuroblastoma with cytokines and 13-cis-retinoic acid after myeloablative therapy. Recent studies using immunohistochemistry of tumor or tumor cells in marrow have shown that some neuroblastomas are negative for GD2. Dinutuximab and other anti-GD2 antibodies are increasingly used in combination with cytotoxic chemotherapy for treating relapsed neuroblastoma, so it is important to be able to identify patients with tumor cells with low GD2 expression, as such patients may experience toxicity but not benefit from the antibody therapy. As the most common clinical samples available for relapsed neuroblastoma are bone marrow aspirates, we developed a method to quantify dinutuximab binding density and the frequency of neuroblastoma cells positive for the antibody in bone marrow aspirates. Here, we describe a multi-color flow cytometry assay that employs non-GD2 antibodies to identify neuroblastoma cells in a mixed population (tumor, bone marrow, or blood) and an anti-GD2 antibody to quantify both the frequency and density of GD2 expression on neuroblastoma cells.

Targeting GD2 after allogeneic SCT: effector cell composition defines the optimal use of ch14.18 and the bispecific antibody construct NG-CU (GD2-CD3).

We investigated whether T cell-recruiting bispecific anti-CD3/GD2 antibody NG-CU might be an alternative to therapeutic anti-GD2 monoclonal antibody (mAb) ch14.18, mediating complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC) through natural killer (NK) cells for immunotherapy in high-risk/relapsed neuroblastoma after autologous/allogeneic stem cell transplantation (auto/alloSCT). Different antibody concentrations and effector-to-target ratios (E:T) were evaluated using xCELLigence RTCA system, peripheral blood mononuclear cells (PBMCs) (healthy donors and patients after alloSCT), and neuroblastoma cell lines (LS/LAN-1). Mean specific lysis of LS cells utilizing PBMCs from healthy donors and ch14.18 (1µg/ml) was 40/66/75% after 12/24/48 h compared to 66/93/100% in the presence of NG-CU (100 ng/ml). NG-CU showed enhanced cytotoxicity compared to ch14.18, even at lower concentrations and E:T ratios, and completely eradicated LS cells after 72 h. To decipher the influence of effector cell subsets on lysis, different ratios of T and NK cells were tested. At a ratio of 1:1, ch14.18 was more effective than NG-CU. Using patient PBMCs taken at different time points posttransplant, significant lysis with both constructs was detectable depending on percentages and total numbers of T and NK cells; in the early posttransplant phase, NK cells were predominant and ch14.18 was superior, whereas later on, T cells represented the majority of immune cells and NG-CU was more effective. Our study highlights the importance of analyzing effector cell subsets in patients before initiating antibody-based therapy. Consequently, we propose an adjusted administration of both antibody constructs, considering the state of posttransplant immune recovery, to optimize anti-tumor activity.

Mechanisms, Characteristics, and Treatment of Neuropathic Pain and Peripheral Neuropathy Associated with Dinutuximab in Neuroblastoma Patients.

Prognosis of metastatic neuroblastoma is very poor. Its treatment includes induction chemotherapy, surgery, high-dose chemotherapy, radiotherapy, and maintenance with retinoic acid, associated with the anti-GD2 monoclonal antibody (ch14.18) dinutuximab. Immunotherapy determined a significant improvement in survival rate and is also utilized in relapsed and resistant neuroblastoma patients. Five courses of dinutuximab 100 mg/m2 are usually administered as a 10-day continuous infusion or over 5 consecutive days every 5 weeks. Dinutuximab targets the disialoganglioside GD2, which is highly expressed on neuroblastoma cells and minimally present on the surface of normal human neurons, peripheral pain fibers, and skin melanocytes. Anti GD2 antibodies bind to surface GD2 and determine the lysis of neuroblastoma cells induced by immune response via the antibody-dependent cellular cytotoxicity and the complement-dependent cytotoxicity. Dinutuximab has significant side effects, including neuropathic pain, peripheral neuropathy, hypersensitivity reactions, capillary leak syndrome, photophobia, and hypotension. The most important side effect is neuropathic pain, which is triggered by the same antibody–antigen immune response, but generates ectopic activity in axons, which results in hyperalgesia and spontaneous pain. Pain can be severe especially in the first courses of dinutuximab infusion, and requires the administration of gabapentin and continuous morphine infusion. This paper will focus on the incidence, mechanisms, characteristics, and treatment of neuropathic pain and peripheral neuropathy due to dinutuximab administration in neuroblastoma patients.

Abstract IA09: Immunotherapeutic approaches for pediatric solid tumors

Abstract For patients with primary metastatic or recurrent soft tissue sarcomas, cytotoxic chemotherapy is currently the primary treatment modality. Despite intensive chemotherapy, the outcome is poor and additional new therapeutic strategies in combination with chemotherapy have to be investigated. Immunotherapy, which involves the patient’s own or a new allogeneic immune system, might have great potential to improve the outcome of affected patients. We have focused on the use of haploidentical transplantation as a form of intensive immunotherapy in order to utilize a graft-versus-solid tumor effect, which might be exerted by donor-derived alloreactive Natural Killer (NK) cells, but also by donor-derived T cells. In a first pilot trial, we have transplanted 26 patients with relapsed neuroblastoma from a haploidentical donor. The transplant-related mortality (TRM) was 0% and the overall survival (OS) was 20%. We then started a protocol using haploidentical transplantation in 68 patients followed post-transplant by 6-9 cycles of the monoclonal anti-GD2 antibody ch14.18CHO. The TRM was 5% and the 3-year OS is 58%. In addition to neuroblastoma, we also hope to apply similar strategies to other pediatric advanced solid tumors including Ewing’s sarcoma, rhabdomyosarcoma, and others. We conclude that haploidentical transplantation of patients with relapsed/refractory solid tumors is a platform on which further immunotherapeutic strategies can be developed, such as antibodies directed against other targets than GD2, such as CD276, or bispecific T-cell engagers (BiTEs), chimeric antigen receptor (CAR) T-cells or CAR NK cells, or antibody/cytokine fusion proteins, and these approaches will be discussed. The main goal of immunotherapy, however, must be to establish a long-term memory immune response against the tumor, and haploidentical transplantation might facilitate such a response. Citation Format: Rupert Handgretinger. Immunotherapeutic approaches for pediatric solid tumors [abstract]. In: Proceedings of the AACR Special Conference on the Advances in Pediatric Cancer Research; 2019 Sep 17-20; Montreal, QC, Canada. Philadelphia (PA): AACR; Cancer Res 2020;80(14 Suppl):Abstract nr IA09.

Aetiology of Neuropathic Pain (NP) Along with Role of Gabapentinoids Like Pregabalin and Gabapentin in Treating the Excruciating Pain Besides Other Newer Alternatives-a Systematic Review

Neuropathic pain (NP) by definition is a problem that involves the somatosensory system either as a manifestation as disease or as a lesion. Lot of differing causes either of central/peripheral origin can stimulate NP and that might affect life’s quality badly. Worldwide prevalence of NP varies from 6.9-10% with spinal cord injury (SCI) explaining 40% of them. The 2nd commonest cause is diabetic peripheral neuropathy (DPN) that accounts for 22-28% of type 2 diabetes mellitus (T2DM). After having reviewed thoroughly how to manage diabetic neuropathic pain here we decided to conduct a systematic review on varying causes of NP and the role of gabapentenoids in managing the excruciating pain. Besides newer opioid analogues not having addictive potential like fentanyl matrix with its availability in intradermal formulations, delta opioid receptor agonist BBI-11008, an innovative analog N-(1-benzylpiperidin-4-yl)-4-fluorobenzamide (LMH2), that is like haloperidol, along with advantages of Gabapentin-ER as well as therapy of trigeminal neuralgia with anticonvulsants like carbamazepine and use in Immunotherapy utilizing 14,18 anti GD2 antibody (ch14.18) associated excruciating pain and in Meralgia paraesthetica (MP) is discussed besides alternative therapies when gabapentenoids fail.

Multimodal Analgesic Plan for Children Undergoing Chimeric 14.18 Immunotherapy.

Immunotherapy with the chimeric 14.18 anti-GD2 antibody (ch14.18) is associated with severe neuropathic pain. Different analgesic modalities have been employed, but pain management remains challenging and side effects such as desaturation, bradycardia, and hypotension have been reported. We retrospectively analyzed the efficacy of a multimodal regimen based on gabapentin, ketamine, and morphine in controlling pain during ch14.18 chemotherapy. In our cohort, the pain was low, desaturation and hypotension were infrequent, and no episode of bradycardia was reported. Morphine consumption was similar to other studies. Our results suggest that this regimen may be a valid analgesic option in children undergoing ch14.18 infusion.

Reduction of CD11b+ myeloid suppressive cells augments anti-neuroblastoma immune response induced by the anti-GD2 antibody ch14.18/CHO

ABSTRACT Neuroblastoma (NB) still remains a major challenge in pediatric oncology. We recently showed CD11b+-dependent upregulation of the PD-1/PD-L1 checkpoint on NB cells treated with the chimeric anti-GD2 antibody (Ab) ch14.18/CHO. Here, we report effects of reduction of CD11b+ myeloid suppressive cells on ch14.18/CHO immunotherapy against NB. Flow cytometry, immunohistochemistry and RT-PCR were used to assess tumor infiltrating leukocytes and expression of myeloid suppressive cell-associated genes. XTT assay was used to show impact of 5-FU on tumor and effector cells. Antitumor effects of the combined treatment with ch14.18/CHO and reduction of myeloid suppressive cells were evaluated in a syngeneic NB mouse model. Tumor tissue of untreated mice showed a strong infiltration by CD11b+ cells (53% of all tumor infiltrating leukocytes). RT-PCR analysis of tumors revealed strong expression of the myeloid suppressive cell-associated genes analyzed with the strongest induction of M-CSFr, CCL2, IL-1β, IL-4, IL-6 r, IL-8, Arg1, and NOS2. Compared to controls, application of anti-CD11b Ab resulted in reduction of both CD11b+ cells in tumors and expression of myeloid suppressive cell-associated genes as well as delayed tumor growth and prolonged survival. These effects could be further improved by 5-FU. Importantly, the combinatorial immunotherapy with ch14.18/CHO and 5-FU showed the strongest antitumor effects and superior survival rates. In conclusion, reduction of immune suppressive myeloid cells augments anti-NB efficacy of a ch14.18/CHO-based immunotherapy representing a new effective treatment strategy against GD2-positive cancers.

Low CD4⁺/CD25⁺/CD127⁻ regulatory T cell- and high INF-γ levels are associated with improved survival of neuroblastoma patients treated with long-term infusion of ch14.18/CHO combined with interleukin-2

ABSTRACTImmunotherapy with the anti-GD2 antibody (Ab) ch14.18/CHO in combination with interleukin 2 (IL-2) has improved survival of high-risk neuroblastoma (NB) patients. Here, we report immunotherapy-related effects on circulating NK cells, regulatory T cells (Tregs), granulocytes as well as on Ab-dependent cell-mediated cytotoxicity (ADCC) and cytokines IFN-γ, IL-6, IL-10, IL-18 and CCL2 and their association with progression-free survival (PFS).In a closed single-center program, 53 patients received five cycles of 6 × 106 IU/m2 subcutaneous IL-2 (d1-5; 8–12) combined with long-term infusion (LTI) of 100 mg/m2 ch14.18/CHO (d8-18). Immune cells and cytokines were analyzed by flow cytometry and ADCC by calcein-AM-based cytotoxicity assay.IL-2 administration increased cytotoxic NK cell-, eosinophil- and Treg counts in cycle 1 (2.9-, 3.1- and 20.7-fold, respectively) followed by further increase in subsequent cycles, whereas neutrophil levels were elevated only after the ch14.18/CHO infusion (2.4-fold change). Serum concentrations of IFN-γ, IL-6, IL-10, IL-18 and CCL2 in cycle 1 were increased during the combinatorial therapy (peak levels of 3,656 ± 655 pg/ml, 162 ± 38 pg/ml, 20.91 ± 4.74 pg/ml, 1,584 ± 196 pg/ml and 2,159 ± 252 pg/ml, respectively). Surprisingly, we did not observe any correlation between NK-, eosinophil- or neutrophil levels and PFS. In contrast, patients with low Tregs showed significantly improved PFS compared to those who had high levels. Treg counts negatively correlated with INF-γ serum concentrations and patients with high INF-γ and IL-18 had significantly improved survival compared to those with low levels.In conclusion, LTI of ch14.18/CHO in combination with IL-2 resulted in Treg induction that inversely correlated with IFN-γ levels and PFS.

Immunotherapy with anti-GD2 antibody ch14.18/CHO±IL2 within the HR-NBL1/SIOPEN trial to improve outcome of high-risk neuroblastoma patients compared to historical controls.

10539Background: Randomization of immunotherapy versus standard was not possible in the HR-NBL1/SIOPEN trial. In order to explore an impact of immunotherapy on outcome, we used trial patients prior...

Association of regulatory- and helper-T- cells with inferior survival of neuroblastoma patients treated with long-term infusion of ch14.18/CHO combined with interleukin-2.

10530Background: Long-term infusion (LTI) of the anti-GD2 antibody (Ab) ch14.18/CHO in combination with interleukin-2 (IL-2) prolongs survival in patients (pts) with high-risk neuroblastoma compare...

PD-1 blockade augments anti-neuroblastoma immune response induced by anti-GD2 antibody ch14.18/CHO

ABSTRACTImmunotherapy with anti-GD2 antibody (Ab) ch14.18/CHO is effective for treatment of high-risk neuroblastoma (NB) patients and is mainly based on GD2-specific Ab-dependent cellular cytotoxicity (ADCC). Strategies to further enhance the efficacy are important and currently explored in prospective clinical trials randomizing ch14.18/CHO ± IL-2. Recently, expression of programmed death 1 (PD-1) inhibitory receptor by effector cells and its ligand (PD-L1) by tumor cells has been shown. Here, we report for the first time effects of PD-1 blockade on ch14.18/CHO-based immunotherapy and mechanisms involved.Expression of PD-1 and PD-L1 on NB and effector cells was analyzed by RT-PCR and flow cytometry in the presence of ch14.18/CHO and/or IL-2. The effect of PD-1 blockade on ch14.18/CHO-mediated anti-NB immune response was evaluated using anti-PD-1 Ab both in vitro (Nivolumab) and in a syngeneic PD-L1+/GD2+ NB mouse model (anti-mouse PD-1).Culture of NB cells LA-N-1 (low PD-L1 baseline expression) with leukocytes and subtherapeutic ch14.18/CHO concentrations for 24 h induced strong upregulation of PD-L1, which was further increased by IL-2 resulting in complete inhibition of ch14.18/CHO-mediated ADCC. Importantly, blockade with Nivolumab reversed the PD-L1-dependent inhibition of ADCC. Similarly, co-incubation with anti-CD11b Ab abrogated the PD-L1 upregulation and restored ADCC. Mice treated with ch14.18/CHO in combination with PD-1 blockade showed a strong reduction of tumor growth, prolonged survival and the highest cytotoxicity against NB cells.In conclusion, ch14.18/CHO-mediated effects upregulate the inhibitory immune checkpoint PD-1/PD-L1, and combination of ch14.18/CHO with PD-1 blockade results in synergistic treatment effects in mice representing a new effective treatment strategy against GD2-positive cancers.

Effect of PD1/PD-L1 checkpoint blockade on efficacy of anti-GD2 antibody ch14.18/CHO in neuroblastoma.

10548 Background: Immunotherapy (IT) with anti-GD2 antibody (Ab) ch14.18/CHO is effective for treatment of high-risk neuroblastoma (NB) patients mainly due to induction of GD2-specific Ab-dependent cellular cytotoxicity (ADCC). Methods to further enhance the effect are important and currently explored in prospective clinical trials randomizing ch14.18/CHO ± scIL-2. Programmed death-1 (PD-1) is an inhibitory receptor expressed by activated T- and NK-cells, and cancer cells express PD-1 ligand. Here, we report for the first time effect and mechanism of PD-1/PD-L1 blockade in the context of ch14.18/CHO-based IT in preclinical models. Methods: Expression of PD-L1 and PD-1 on NB cells and leukocytes was analyzed by RT-PCR and flow cytometry in the presence of ch14.18/CHO or IL-2. Mechanism of PD-L1 induction was analyzed with anti-CD11b Ab. The effect of PD-1/PD-L1 blockade on ch14.18/CHO-mediated anti-NB immune response was evaluated using anti-PD-1 Ab both in vitro (Nivolumab) and in the syngeneic GD2+ NB NXS2 mouse model (anti-mouse PD-1). Mice (n = 10) were treated with ch14.18/CHO (5x300 µg, i.p.) in combination with anti-PD-1 (8x250 µg, i.p.), and compared to controls. Results: Culture of LA-N-1 (low PD-L1 baseline expression) in the presence of leukocytes and subtherapeutic ch14.18/CHO concentrations for 24h induced strong upregulation of PD-L1 resulting in complete inhibition of ADCC mediated by ch14.18/CHO. Co-incubation with anti-CD11b Ab abrogated this PD-L1 upregulation. Importantly, blockade with Nivolumab reversed the PD-L1-dependent inhibition of ADCC. Mice treated with ch14.18/CHO in combination with PD-1 blockade showed a strong reduction of tumor growth and prolonged survival as well as the highest level of NB cell lysis mediated by serum and leukocytes compared to controls. Conclusions: Ch14.18/CHO-mediated effects upregulate the inhibitory checkpoint PD-1/PD-L1 and combination of ch14.18/CHO with PD-1/PD-L1 blockade results in synergistic treatment effects in mice. This concept will be evaluated in a clinical trial.

Survival of neuroblastoma patients treated by long-term infusion of anti-GD2 antibody ch14.18/CHO and killer-cell Ig-like receptor (KIR) genotypes and Fcγ-receptor polymorphisms.

111 Background: Receptors expressed on natural killer (NK) cells and their ligands on target cells involved in antibody-dependent cell-mediated cytotoxicity (ADCC) may influence outcome in patients (pts) with high-risk relapsed/refractory neuroblastoma (NB) treated by long-term infusion (LTI) of anti-GD2 antibody ch14.18/CHO Methods: 53 pts received 6x106 IU/m2 sc IL-2 (d1-5; 8-12), LTI of 100 mg/m2 ch14.18/CHO (d8-17) and 160 mg/m2 oral 13-cis-RA (d19-32) in a closed single center program (53 pts) (APN311-303). Polymorphisms in Fcγ-receptor genes 2A (H131R), -3A (V158F) and -3B (NA1/NA2), and KIR- as well as KIR ligand expression (HLA-C1; HLA-C2; HLA-Bw4+) were determined by real-time PCR. Results: The survival update of the APN311-303 cohort revealed a 5-y OS of 56.4±7.1% (mean OS 4.35y [0.3-6.2y]) and a 5-y PFS of 29.1±6.3% (mean PFS 2.4y [0.1 - 5.9y]). Median TTP/PFS was 1.35 y (95% CI: 0.21-2.48 y). This result is clearly superior to historical controls not treated with ch14.18/CHO with a 5-y OS of 14.8±6.8% (p < 0.005), indicating clinical efficacy of the treatment. In this cohort, we identified 26/53 pts with the NK- stimulatory KIR haplotype (2DS2+) who had superior OS- and PFS-rates compared to 18/53 pts with an inhibitory haplotype and KIR/KIR-ligand match (2DS2-, 3DL1+, Bw4+) (p < 0.02). Similarly, we found 33/53 pts with low affinity FCGR alleles (FCGR2A-H131R/R and/or FCGRA3A-V158 F/F). These patients showed lower PFS rates compared to 20/53 patients with high affinity FCGR polymorphisms (p < 0.01). ADCC analysis on day 15 of cycle 1 showed higher levels in the pt group with NK- stimulatory versus NK- inhibitory KIR/KIR ligand haplotypes (23±6 % vs. 6±2%, p < 0.01). A similar effect was observed in pts with high affinity FCGR polymorphisms with an ADCC increase of 20±6% compared to 11±2% in the low affinity FCGR control. Conclusions: KIR-haplotypes and FCGR- polymorphisms correlated with the functional immune parameter ADCC and clinical outcome, and thus support the relevance of ADCC for clinical efficacy of ch14.18/CHO in neuroblastoma.

Anti-GD2-ch14.18/CHO coated nanoparticles mediate glioblastoma (GBM)-specific delivery of the aromatase inhibitor, Letrozole, reducing proliferation, migration and chemoresistance in patient-derived GBM tumor cells.

Aromatase is a critical enzyme in the irreversible conversion of androgens to oestrogens, with inhibition used clinically in hormone-dependent malignancies. We tested the hypothesis that targeted aromatase inhibition in an aggressive brain cancer called glioblastoma (GBM) may represent a new treatment strategy. In this study, aromatase inhibition was achieved using third generation inhibitor, Letrozole, encapsulated within the core of biodegradable poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs). PLGA-NPs were conjugated to human/mouse chimeric anti-GD2 antibody ch14.18/CHO, enabling specific targeting of GD2-positive GBM cells. Treatment of primary and recurrent patient-derived GBM cells with free-Letrozole (0.1 μM) led to significant decrease in cell proliferation and migration; in addition to reduced spheroid formation. Anti-GD2-ch14.18/CHO-NPs displayed specific targeting of GBM cells in colorectal-glioblastoma co-culture, with subsequent reduction in GBM cell numbers when treated with anti-GD2-ch14.18-PLGA-Let-NPs in combination with temozolomide. As miR-191 is an estrogen responsive microRNA, its expression, fluctuation and role in Letrozole treated GBM cells was evaluated, where treatment with premiR-191 was capable of rescuing the reduced proliferative phenotype induced by aromatase inhibitor. The repurposing and targeted delivery of Letrozole for the treatment of GBM, with the potential role of miR-191 identified, provides novel avenues for target assessment in this aggressive brain cancer.

Neuroblastoma patients with high-affinity FCGR2A, -3A and stimulatory KIR 2DS2 treated by long-term infusion of anti-GD2 antibody ch14.18/CHO show higher ADCC levels and improved event-free survival

ABSTRACTPolymorphisms in Fc-gamma-receptor (FCGR) genes as well as killer cell immunoglobulin-like receptor (KIR) and KIR ligand (KIRL) repertoires may influence antitumor effects of monoclonal antibodies (mAb). Here, we systematically analyzed high- and low-affinity FCGR2A and -3A genotypes as well as stimulating and inhibitory KIR/KIRL combinations in 53 neuroblastoma (NB) patients treated by long-term infusion (LTI) of anti-GD2 IgG1 Ab ch14.18/CHO using validated real-time PCR methods.Patients with high-affinity FCGR2A and -3A genotypes showed a higher level of Ab-dependent cell-mediated cytotoxicity (ADCC) on day 8 after the start of ch14.18/CHO and superior event-free survival (EFS) compared to patients with low FCGR genotypes. Similar observations were made for patients with stimulatory KIR/KIRL haplotype B (combination of KIR genes including activating receptor genes) compared to inhibitory haplotype A (a fixed set of genes encoding for inhibitory receptors, except 2DS4) and stronger effects were found in patients when haplotype B and high-affinity FCGRs were combined. Surprisingly, independent analysis of KIRs showed a major role of activating KIR 2DS2 for high ADCC levels and prolongation of EFS. The greatest effect was observed in 2DS2-positive patients that also had high-affinity FCGR2A and -3A genotypes.In summary, the presence of the activating KIR 2DS2 has a major effect on ADCC levels and survival in NB patients treated by LTI of ch14.18/CHO and may therefore be a useful biomarker in combination with FCGR polymorphisms for Ab-based immunotherapies.

Phase I bridging study of ch14.18/CHO long-term infusion in recurrent or refractory neuroblastoma patients in Japan.

10568Background: The primary objective of this study was to assess safety and toxicity of anti-GD2 antibody ch14.18/CHO continuous long term infusion (LTI) used as single agent in Japanese pediatri...

Phase II clinical trial with long-term infusion of anti-GD2 antibody ch14.18/CHO in combination with interleukin-2 (IL2) in patients with high risk neuroblastoma.

10562Background: A new delivery method of anti-GD2 antibody ch14.18/CHO by long term infusion (LTI) may improve the toxicity profile but maintain effective immune modulation and clinical activity i...

Correlation of killer-cell Ig-like receptor (KIR) haplotypes and Fcγ-receptor polymorphisms with survival of high-risk relapsed/refractory neuroblastoma patients treated by long-term infusion of anti-GD2 antibody ch14.18/CHO.

10548Background: Receptors expressed on natural killer (NK) cells and their ligands on target cells involved in antibody-dependent cell-mediated cytotoxicity (ADCC) may predict outcome in patients ...

Abstract A032: Immunotherapy with ch14.18/CHO in combination with IL2 is active and effective in high-risk relapsed/refractory neuroblastoma patients

Abstract Background: Ganglioside GD2 is a glycolipid highly expressed on neuro-ectodermal tumors including melanoma and neuroblastoma (NB). It is ranked on position 12 of the list of tumor associated antigens by the NCI. Anti-GD2 antibody (Ab) ch14.18/CHO targets this antigen and effectively orchestrates innate immune effector mechanisms against GD2 expressing malignancies. However, one on target effect of anti-GD2 Abs is the induction of neuropathic pain when applied as short term infusion (STI) requiring co-medication with intravenous morphine. Here we investigated whether long-term infusion (LTI) of anti-GD2 Ab ch14.18/CHO may have an improved pain toxicity profile and at the same time mediate an effective immune response in patients (pts) with high risk relapsed/refractory NB which translates to objective clinical responses and an improved survival. Methods: 97 pts received 6x106 IU/m2 sc IL2 (d1-5; 8-12), LTI of 100 mg/m2 ch14.18/CHO (d8-17) and 160 mg/m2 oral 13-cis-RA (d19-32) in an ongoing SIOPEN Phase II study (APN311-202) (NCT01701479) (44 pts) and a closed single center program (53 pts) (APN311-303). Response assessments followed INRG criteria. Serum ch14.18/CHO concentration-time curves were determined by validated ELISA methods and pharmacokinetics parameter were analyzed using standard non-compartmental methods. Fcγ;-receptor polymorphisms FCGR2A (H131R), -3A (V158F) and -3B (NA1/NA2) and patient-specific antibody-dependent cell-mediated cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC) and whole blood cytotoxicity (WBT) responses were determined. Results: LTI was associated with low pain scores and a decreasing morphine usage compared to STI. Clinical overall responses were 30% (APN311-303) and 31% (APN311-202). The survival update of the APN311-303 cohort revealed a 1-y & 4-y OS of 94.2±3.2% & 60.9±9.0% (median FU 2.9y [0.7-5.2y]) and a 1-y & 4-y PFS of 54.4±6.9% & 32.3%±6.9% (median FU 2.8y [0.7 - 4.9y]). Median TTP was 571d (95% CI: 232.7d). The comparator is the reported historical gold standard for relapsed refractory NB patients with 1-y & 4-y PFS of 19±2% & 8±3% and OS of 56±3% & 14±4% and a median TTP of 63 d (95% CI: 56.8d). NB pts with high affinity FCGR alleles and an increase in ADCC (cut off 15%) are associated with longer PFS and OS rates (p<0.03; p<0.005), supporting NK-cell mediated ADCC as the mechanism of action. Parameters of immune modulation (CDC, and WBT) and PK of ch14.18/CHO were comparable between APN311-202 and -303 cohorts. PK of ch14.18/CHO was analyzed in cycle 1: Cmax=12.2±0.4μg/ml, t½=8.4±1.1 d, AUC=145.3± 5.8 μg*d/ml, Vdss=9.3±0.5L/m2. A pro-inflammatory cytokine response (IL-2, IL-6, IL-8, IFNγ) translated into the expansion of effector NK- (3x) and T-cells (2x). We observed HACA in 17/97 pts (17.5%) of which only 9/97 (9.3%) were neutralizing with respect to the inhibition of CDC and WBT activity. In HACA negative patients, levels of ch14.18/CHO and functional parameters (CDC and WBT) analyzed before subsequent treatment cycles indicate persistent anti-NB activity for the entire treatment period. Conclusion: LTI of ch14.18/CHO has an improved pain toxicity profile and at the same time is active and effective in high-risk relapsed/refractory NB. Citation Format: Holger N. Lode, Dominique Valteau-Couanet, Alberto Garaventa, Juliet Gray, Victoria Castel, Isaac Yaniv, Nikolai Siebert, Christian Jensen, Stefanie Endres, Lena Pill, Christin Eger, Diana Seidel, Madlen Jüttner, Silke Kietz, Karoline Ehlert, Evelyne Janzek, Carla Manzitti, Ina Müller, Hans Loibner, Ruth Ladenstein. Immunotherapy with ch14.18/CHO in combination with IL2 is active and effective in high-risk relapsed/refractory neuroblastoma patients. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr A032.

Long-term infusion of anti-GD2 antibody ch14.18/CHO in combination with interleukin-2 (IL2) activity and efficacy in high-risk relapsed/refractory neuroblastoma patients.

TPS10080 Background: Long-term infusion (LTI) of anti-GD2 antibody ch14.18/CHO may improve outcome in patients (pts) with high risk relapsed/refractory neuroblastoma (NB). Methods: 97 pts received ...