Jacek Gan

Antitumor Activity of Hu14.18-IL2 in Patients With Relapsed/Refractory Neuroblastoma: A Children's Oncology Group (COG) Phase II Study

PURPOSE The hu14.18-IL2 fusion protein consists of interleukin-2 molecularly linked to a humanized monoclonal antibody that recognizes the GD2 disialoganglioside expressed on neuroblastoma cells. This phase II study assessed the antitumor activity of hu14.18-IL2 in two strata of patients with recurrent or refractory neuroblastoma. PATIENTS AND METHODS Hu14.18-IL2 was given intravenously (12 mg/m(2)/daily) for 3 days every 4 weeks for patients with disease measurable by standard radiographic criteria (stratum 1) and for patients with disease evaluable only by [(123)I]metaiodobenzylguanidine (MIBG) scintigraphy and/or bone marrow (BM) histology (stratum 2). Response was established by independent radiology review as well as BM histology and immunocytology, and durability was assessed by repeat evaluation after more than 3 weeks. RESULTS Thirty-nine patients were enrolled (36 evaluable). No responses were seen in stratum 1 (n = 13). Of 23 evaluable patients in stratum 2, five patients (21.7%) responded; all had a complete response (CR) of 9, 13, 20, 30, and 35+ months duration. Grade 3 and 4 nonhematologic toxicities included capillary leak, hypoxia, pain, rash, allergic reaction, elevated transaminases, and hyperbilirubinemia. Two patients required dopamine for hypotension, and one patient required ventilatory support for hypoxia. Most toxicities were reversible within a few days of completing a treatment course and were expected based on phase I results. CONCLUSION Patients with disease evaluable only by MIBG and/or BM histology had a 21.7% CR rate to hu14.8-IL2, whereas patients with bulky disease did not respond. Hu14.18-IL2 warrants further testing in children with nonbulky high-risk neuroblastoma.

Phase I Study of Chimeric Human/Murine Anti–Ganglioside GD2 Monoclonal Antibody (ch14.18) With Granulocyte-Macrophage Colony-Stimulating Factor in Children With Neuroblastoma Immediately After Hematopoietic Stem-Cell Transplantation: A Children’s Cancer Group Study

PURPOSE Ganglioside G(D2) is strongly expressed on the surface of human neuroblastoma cells. It has been shown that the chimeric human/murine anti-G(D2) monoclonal antibody (ch14.18) can induce lysis of neuroblastoma cells by antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity. The purposes of the study were (1) to determine the maximum-tolerated dose (MTD) of ch14.18 in combination with standard dose granulocyte-macrophage colony-stimulating factor (GM-CSF) for patients with neuroblastoma who recently completed hematopoietic stem-cell transplantation (HSCT), and (2) to determine the toxicities of ch14.18 with GM-CSF in this setting. PATIENTS AND METHODS Patients became eligible when the total absolute phagocyte count (APC) was greater than 1, 000/microL after HSCT. ch14.18 was infused intravenously over 5 hours daily for 4 consecutive days. Patients received GM-CSF 250 microg/m(2)/d starting at least 3 days before ch14.18 and continued for 3 days after the completion of ch14.18. The ch14.18 dose levels were 20, 30, 40, and 50 mg/m(2)/d. In the absence of progressive disease, patients were allowed to receive up to six 4-day courses of ch14.18 therapy with GM-CSF. Nineteen patients with neuroblastoma were treated. RESULTS A total of 79 courses were administered. No toxic deaths occurred. The main toxicities were severe neuropathic pain, fever, nausea/vomiting, urticaria, hypotension, mild to moderate capillary leak syndrome, and neurotoxicity. Three dose-limiting toxicities were observed among six patients at 50 mg/m(2)/d: intractable neuropathic pain, grade 3 recurrent urticaria, and grade 4 vomiting. Human antichimeric antibody developed in 28% of patients. CONCLUSION ch14.18 can be administered with GM-CSF after HSCT in patients with neuroblastoma with manageable toxicities. The MTD is 40 mg/m(2)/d for 4 days when given in this schedule with GM-CSF.

A Phase I Clinical Trial of the hu14.18-IL2 (EMD 273063) as a Treatment for Children with Refractory or Recurrent Neuroblastoma and Melanoma: a Study of the Children’s Oncology Group

Purpose: Evaluate the clinical safety, toxicity, immune activation/modulation, and maximal tolerated dose of hu14.18-IL2 (EMD 273063) in pediatric patients with recurrent/refractory neuroblastoma and other GD2-positive solid tumors. Experimental Design: Twenty-seven pediatric patients with recurrent/refractory neuroblastoma and one with melanoma were treated with a humanized anti-GD2 monoclonal antibody linked to human interleukin 2 (IL-2). Cohorts of patients received hu14.18-IL2, administered i.v. over 4 hours for three consecutive days, at varying doses. Patients with stable disease, partial, or complete responses were eligible to receive up to three additional courses of therapy. Results: Most of the clinical toxicities were anticipated and similar to those reported with IL-2 and anti-GD2 monoclonal antibody therapy and to those noted in the initial phase I study of hu14.18-IL2 in adults with metastatic melanoma. The maximal tolerated dose was determined to be 12 mg/m2/d, with agent-related dose-limiting toxicities of hypotension, allergic reaction, blurred vision, neutropenia, thrombocytopenia, and leukopenia. Three patients developed dose-limiting toxicity during course 1; seven patients in courses 2 to 4. Two patients required dopamine for hypotension. There were no treatment-related deaths, and all toxicity was reversible. Treatment with hu14.18-IL2 led to immune activation/modulation as evidenced by elevated serum levels of soluble IL-2 receptor α (sIL2Rα) and lymphocytosis. The median half-life of hu14.18-IL2 was 3.1 hours. There were no measurable complete or partial responses to hu14.18-IL2 in this study; however, three patients did show evidence of antitumor activity. Conclusion: Hu14.18-IL2 (EMD 273063) can be administered safely with reversible toxicities in pediatric patients at doses that induce immune activation. A phase II clinical trial of hu14.18-IL2, administered at a dose of 12 mg/m2/d × 3 days repeated every 28 days, will be done in pediatric patients with recurrent/refractory neuroblastoma.

Phase I Clinical Trial of the Immunocytokine EMD 273063 in Melanoma Patients

PURPOSE To evaluate the safety, toxicity, in vivo immunologic activation, and maximum-tolerated dose (MTD) of EMD 273063 (hu14.18-IL-2) in patients with metastatic melanoma. PATIENTS AND METHODS Thirty-three patients were treated with EMD 273063, a humanized anti-GD2 monoclonal antibody (mAb) linked to interleukin-2 (IL-2). EMD 273063 was given as a 4-hour intravenous infusion on days 1, 2, and 3 of week 1. Patients with stabilization or regression of disease could receive a second course of treatment at week 5. Dose levels evaluated were 0.8, 1.6, 3.2, 4.8, 6.0, and 7.5 mg/m2/d. RESULTS Nineteen of 33 patients completed course 1 with stable disease and went on to receive course 2. Eight patients had stable disease on completion of course 2. Grade 3 adverse events included hypophosphatemia (11 patients), hyperglycemia (three patients), hypotension (two patients), thrombocytopenia (one patient), hypoxia (three patients), elevated hepatic transaminases (two patients), and hyperbilirubinemia (one patient). Opioids were required for treatment-associated arthralgias and/or myalgias during 17 of 52 treatment courses. No grade 4 adverse events were observed. Dose-limiting toxicities at the MTD included hypoxia, hypotension, and elevations in AST/ALT. Grade 3 toxicities were anticipated based on prior studies of IL-2 or anti-GD2 mAbs, and all resolved. Immune activation was induced, as measured by lymphocytosis, increased peripheral-blood natural killer activity, and cell numbers, and increased serum levels of the soluble alpha chain of the IL-2 receptor complex. CONCLUSION Treatment with the immunocytokine EMD 273063 induced immune activation and was associated with reversible clinical toxicities at the MTD of 7.5 mg/m2/d in melanoma patients.

Genotypes of NK cell KIR receptors, their ligands, and Fcγ receptors in the response of neuroblastoma patients to Hu14.18-IL2 immunotherapy.

Response to immunocytokine (IC) therapy is dependent on natural killer cells in murine neuroblastoma (NBL) models. Furthermore, killer immunoglobulin-like receptor (KIR)/KIR-ligand mismatch is associated with improved outcome to autologous stem cell transplant for NBL. Additionally, clinical antitumor response to monoclonal antibodies has been associated with specific polymorphic-FcγR alleles. Relapsed/refractory NBL patients received the hu14.18-IL2 IC (humanized anti-GD2 monoclonal antibody linked to human IL2) in a Childrens Oncology Group phase II trial. In this report, these patients were genotyped for KIR, HLA, and FcR alleles to determine whether KIR receptor-ligand mismatch or specific FcγR alleles were associated with antitumor response. DNA samples were available for 38 of 39 patients enrolled: 24 were found to have autologous KIR/KIR-ligand mismatch; 14 were matched. Of the 24 mismatched patients, 7 experienced either complete response or improvement of their disease after IC therapy. There was no response or comparable improvement of disease in patients who were matched. Thus KIR/KIR-ligand mismatch was associated with response/improvement to IC (P = 0.03). There was a trend toward patients with the FcγR2A 131-H/H genotype showing a higher response rate than other FcγR2A genotypes (P = 0.06). These analyses indicate that response or improvement of relapsed/refractory NBL patients after IC treatment is associated with autologous KIR/KIR-ligand mismatch, consistent with a role for natural killer cells in this clinical response.

A Phase I/IB trial of murine monoclonal anti-GD2 antibody 14.G2a plus interleukin-2 in children with refractory neuroblastoma

The murine monoclonal antibody (MoAb) 14.G2a recognizes GD2, a disialoganglioside expressed in tumors of neuroectodermal origin, and facilitates antibody dependent cellular cytotoxicity (ADCC) in vitro. When given in vivo, interleukin‐2 (IL‐2) can increase ADCC by enhancing the activity and number of circulating lymphocytes.

Phase I Study of ch14.18 With Granulocyte-Macrophage Colony-Stimulating Factor and Interleukin-2 in Children With Neuroblastoma After Autologous Bone Marrow Transplantation or Stem-Cell Rescue: A Report From the Children's Oncology Group

PURPOSE Recurrence of high-risk neuroblastoma is common despite multimodality therapy. ch14.18, a chimeric human/murine anti-G(D2) antibody, lyses neuroblastoma cells. This study determined the maximum tolerable dose (MTD) and toxicity of ch14.18 given in combination with interleukin-2 (IL-2) after high-dose chemotherapy (HDC)/stem-cell rescue (SCR). Biologic correlates including ch14.18 levels, soluble IL-2 receptor levels, and human antichimeric antibody (HACA) activity were evaluated. PATIENTS AND METHODS Patients were given ch14.18 for 4 days at 28-day intervals. Patients received IL-2 during the second and fourth courses of ch14.18 and granulocyte-macrophage colony-stimulating factor (GM-CSF) during the first, third, and fifth courses. The MTD was determined based on toxicities occurring with the second course. After the determination of the MTD, additional patients were treated to confirm the MTD and to clarify appropriate supportive care. RESULTS Twenty-five patients were enrolled. The MTD of ch14.18 was determined to be 25 mg/m(2)/d for 4 days given concurrently with 4.5 x 10(6) U/m(2)/d of IL-2 for 4 days. IL-2 was also given at a dose of 3 x 10(6) U/m(2)/d for 4 days starting 1 week before ch14.18. Two patients experienced dose-limiting toxicity due to ch14.18 and IL-2. Common toxicities included pain, fever, nausea, emesis, diarrhea, urticaria, mild elevation of hepatic transaminases, capillary leak syndrome, and hypotension. No death attributable to toxicity of therapy occurred. No additional toxicity was seen when cis-retinoic acid (cis-RA) was given between courses of ch14.18. No patient treated at the MTD developed HACA. CONCLUSION ch14.18 in combination with IL-2 was tolerable in the early post-HDC/SCR period. cis-RA can be administered safely between courses of ch14.18 and cytokines.

A Phase I Study of Immunization Using Particle-Mediated Epidermal Delivery of Genes for gp100 and GM-CSF into Uninvolved Skin of Melanoma Patients

Purpose: We examined in vivo particle-mediated epidermal delivery (PMED) of cDNAs for gp100 and granulocyte macrophage colony-stimulating factor (GM-CSF) into uninvolved skin of melanoma patients. The aims of this phase I study were to assess the safety and immunologic effects of PMED of these genes in melanoma patients. Experimental Design: Two treatment groups of six patients each were evaluated. Group I received PMED with cDNA for gp100, and group II received PMED with cDNA for GM-CSF followed by PMED for gp100 at the same site. One vaccine site per treatment cycle was biopsied and divided for protein extraction and sectioning to assess transgene expression, gold-bead penetration, and dendritic cell infiltration. Exploratory immunologic monitoring of HLA-A2+ patients included flow cytometric analyses of peripheral blood lymphocytes and evaluation of delayed-type hypersensitivity to gp100 peptide. Results: Local toxicity in both groups was mild and resolved within 2 weeks. No systemic toxicity could be attributed to the vaccines. Monitoring for autoimmunity showed no induction of pathologic autoantibodies. GM-CSF transgene expression in vaccinated skin sites was detected. GM-CSF and gp100 PMED yielded a greater infiltration of dendritic cells into vaccine sites than did gp100 PMED only. Exploratory immunologic monitoring suggested modest activation of an antimelanoma response. Conclusions: PMED with cDNAs for gp100 alone or in combination with GM-CSF is well tolerated by patients with melanoma. Moreover, pathologic autoimmunity was not shown. This technique yields biologically active transgene expression in normal human skin. Although modest immune responses were observed, additional investigation is needed to determine how to best utilize PMED to induce antimelanoma immune responses.

Phase I Trial of a Novel Anti-GD2 Monoclonal Antibody, Hu14.18K322A, Designed to Decrease Toxicity in Children With Refractory or Recurrent Neuroblastoma

PURPOSE The addition of immunotherapy, including a combination of anti-GD2 monoclonal antibody (mAb), ch14.18, and cytokines, improves outcome for patients with high-risk neuroblastoma. However, this therapy is limited by ch14.18-related toxicities that may be partially mediated by complement activation. We report the results of a phase I trial to determine the maximum-tolerated dose (MTD), safety profile, and pharmacokinetics of hu14.18K322A, a humanized anti-GD2 mAb with a single point mutation (K322A) that reduces complement-dependent lysis. PATIENTS AND METHODS Eligible patients with refractory or recurrent neuroblastoma received escalating doses of hu14.18K322A ranging from 2 to 70 mg/m(2) per day for 4 consecutive days every 28 days (one course). RESULTS Thirty-eight patients (23 males; median age, 7.2 years) received a median of two courses (range, one to 15). Dose-limiting grade 3 or 4 toxicities occurred in four of 36 evaluable patients and were characterized by cough, asthenia, sensory neuropathy, anorexia, serum sickness, and hypertensive encephalopathy. The most common non-dose-limiting grade 3 or 4 toxicities during course one were pain (68%) and fever (21%). Six of 31 patients evaluable for response by iodine-123 metaiodobenzylguanidine score had objective responses (four complete responses; two partial responses). The first-course pharmacokinetics of hu14.18K322A were best described by a two-compartment linear model. Median hu14.18K322A α (initial phase) and β (terminal phase) half-lives were 1.74 and 21.1 days, respectively. CONCLUSION The MTD, and recommended phase II dose, of hu14.18K322A is 60 mg/m(2) per day for 4 days. Adverse effects, predominately pain, were manageable and improved with subsequent courses.

Ex vivo evaluation of anti-EpCAM immunocytokine huKS-IL2 in ovarian cancer.

Abstract: Despite encouraging responses to treatment, 70% to 80% of women with ovarian cancer will recur due to subclinical residual disease. One experimental agent that merits testing in this setting is the immunocytokine huKS-IL2. Immunocytokines are fusion proteins consisting of a humanized monoclonal antibody linked to IL-2 (or other cytokines). The humanized monoclonal antibody (mAb) huKS, which recognizes the epithelial cell adhesion molecule (EpCAM), has been used to construct the immunocytokine huKS-IL2. To determine the potential therapeutic use of huKS-IL2 in ovarian cancer, the authors evaluated the expression of EpCAM in these cancers and investigated the effects of huKS-IL2 on peritoneal white blood cells and peripheral blood mononuclear cells from women with ovarian cancer. EpCAM expression was determined by immunohistochemistry using both huKS-IL2 and the parent KS1/4 antibody. Ascites fluid was collected and the cellular fraction cultured with or without huKS-IL2 to evaluate the cellular content and potential anti-tumor effects of the peritoneal effector cells (PECs). Peritoneal cells were incubated with FITC-conjugated KS antibody to determine the relative amount of EpCAM-positive cells. Nonadherent cells were analyzed by flow cytometry for hematopoietic origin with CD45 mAb and for CD69 expression as an indication of immune cell activation. EpCAM-positive NIH:OVCAR-3 cells were radiolabeled as targets in a chromium release assay with either PECs or PBMCs as effector cells in the presence or absence of 0.25 mcg/mL huKS-IL2. Differences between treatments were determined by t test. Thirty-two of thirty-three (97%) ovarian cancers were found to express EpCAM via immunohistochemistry. Eleven cases were stained using both KS1/4 and huKS-IL2, and identical patterns of staining were seen. All ascites samples tested had EpCAM-positive cells by flow cytometry. The mean fluorescence intensity of CD69 expression on peritoneal WBCs was increased from 20.7 to 43.9 as a result of culturing with huKS-IL2, indicating effector cell activation. In chromium release assays, KS-IL2 facilitated cell lysis of NIH:OVCAR-3 by PBMCs from both healthy controls and patients with ovarian cancer. PECs from all cases tested showed significant cell lysis induced by huKS-IL2 compared with untreated control cultures. Based on these findings, huKS-IL2 warrants further investigation as a potential immunotherapy for patients with epithelial ovarian cancer, preferably in a minimal disease setting as seen after complete cytoreductive surgery, after a complete clinical response to primary therapy, or when elevated CA-125 levels predict recurrent disease prior to clinical relapse.