Phase 1 study of sorafenib and irinotecan in pediatric patients with relapsed or refractory solid tumors.

BACKGROUND: Sorafenib,an orally bioavailable, multitarget tyrosine kinase inhibitor, and irinotecan, a topoisomerase I inhibitor, have demonstrated activity in pediatric and adult malignancies. We evaluated the toxicity, pharmacokinetic (PK), and pharmacogenomic (PGX) profile of sorafenib with irinotecan in children with relapsed or refractory solid tumors and assessed the feasibility of incorporating patient-reported outcome (PRO) measures as an adjunct to traditional endpoints. METHODS: Sorafenib, continuous oral twice daily dosing, was administered with irinotecan, orally, once daily days 1-5, repeated every 21 days (NCT01518413). Based on tolerability, escalation of sorafenib followed by escalation of irinotecan was planned. Three patients were initially enrolled at each dose level. Sorafenib and irinotecan PK analyses were performed during cycle 1. PRO measurements were collected during cycles 1 and 2. RESULTS: Fifteen patients were evaluable. Two of three patients at dose level 2 experienced dose-limiting toxicity (DLT), grade 3 diarrhea, and grade 3 hyponatremia. Therefore, dose level 1 was expanded to 12 patients and two patients had DLT, grade 4 thrombocytopenia, grade 3 elevated lipase. Nine of 15 (60%) patients had a best response of stable disease with four patients receiving ≥6 cycles. CONCLUSIONS: The recommended dose for pediatric patients was sorafenib 150 mg/m2 /dose twice daily with irinotecan 70 mg/m2 /dose daily × 5 days every 21 days. This oral outpatient regimen was well tolerated and resulted in prolonged disease stabilization. There were no significant alterations in the PK profile of either agent when administered in combination. Patients were willing and able to report their subjective experiences with this regimen.

Fundamental problems with pediatric adaptive dosing of carboplatin using nuclear-medicine-based estimates of renal function.

BACKGROUND: Carboplatin is often adaptively dosed based on glomerular filtration rate (GFR), usually estimated by nuclear medicine tests. At least five pediatric adaptive dosing formulas have been developed. In an effort to standardize dosing in Children's Oncology Group protocols, we explored methodologic variation in GFR estimation and adaptive-dosing formula performance. PROCEDURE: Nuclear medicine GFR data from published series of ≥100 children with cancer were compared. Data from patients for whom body surface area, weight, GFR, and tracer half-life were available were used to compare formulas. RESULTS: Differences in methods used to estimate GFR in children with cancer resulted in highly variable population results, with median GFRs ranging from 96 to 150 mL/min/1.73m2 . The choice of adaptive formula had a major impact on calculated dose. When targeting an area under the curve of 7.9 mg/mL • min, the median difference between the formula yielding the lowest and highest carboplatin dose for individual subjects was 289 (range 96-1 737) mg/m2 . CONCLUSIONS: Wide variation in GFR obtained with nuclear-medicine-based tests in children with cancer primarily results from systematic methodologic errors. Formulas for calculating carboplatin dose produce additional and substantial variation that may place children with cancer at unnecessary risk for excessive toxicity or underdosing. These findings indicate a need for the development of a uniform, validated method for GFR determination in children that should be utilized in all centers. Currently, adaptive dosing of carboplatin based on GFR has serious limitations and in most clinical settings should arguably not be used in place of body-surface-area-based dosing.

Voices of children and adolescents on phase 1 or phase 2 cancer trials: A new trial endpoint?

BACKGROUND: Pediatric participants on phase 1 or phase 2 clinical trials for incurable cancer are at risk of experiencing toxicities (adverse events [AEs]) related to trial participation. Multiple AEs are subjective; thus, the real impact of trial treatment cannot be known unless patient subjective reports are solicited. METHODS: The authors assessed the feasibility and acceptability of soliciting symptom, function, and quality of life (QOL) reports from participants aged 8 to 18 years who were enrolled on phase 1/2 clinical trials at 4 cancer centers during the first course of chemotherapy. The authors also assessed the reliability and validity of 6 self-report Patient-Reported Outcomes Measurement Information System (PROMIS) pediatric measures and 4 open-ended interview questions at 2 time points (at the time of trial enrollment [T1] and 3 to 4 weeks later [T2]). RESULTS: The enrollment rate of 75.9% (20 participants) exceeded the feasibility criterion, and missingness of measures by person, measure, and items at T1 and T2 were lower than the acceptability criteria. New QOL themes were limited to the impact of treatment on families and being away from home, family, and friends for treatment. All but one measure at T1 met the reliability criterion and all measures did so at T2. Validity support was limited however because as theorized, mobility decreased and fatigue increased as AEs increased. CONCLUSIONS: Soliciting and documenting symptom, function, and QOL reports from patients aged 8 to 18 years who are enrolled on a phase 1/2 clinical trial is feasible and acceptable to participants, particularly when embedded in trials. Reliable and valid findings can result, making patient self-reported outcomes a possible new trial endpoint. Cancer 2017;123:3799-3806. © 2017 American Cancer Society.

Glomerular hyperfiltration in children with cancer: prevalence and a hypothesis.

BACKGROUND: Glomerular hyperfiltration has recently been reported in children with malignancies and has been attributed to increased solute from breakdown of tumor tissues. OBJECTIVE: To evaluate the prevalence of hyperfiltration in the pediatric oncology population and explore its pathophysiological mechanism. MATERIALS AND METHODS: Tc-99 m diethylenetriaminepentaacetic acid (DTPA) glomerular filtration rate (GFR) examinations (437 studies) and medical records of 177 patients <21 years of age diagnosed with a malignancy between January 2005 and October 2013 were retrospectively reviewed. Hyperfiltration was defined as a GFR ≥ 160 ml/min/1.73 m2. RESULTS: Seventy-seven (43.5%) patients had hyperfiltration in at least one GFR exam. A significantly higher percentage of patients with central nervous system (CNS) tumors (63.6%) had hyperfiltration when compared to other tumor types (27.3%, P < 0.001). No association was found between hyperfiltration and age, gender, race or bone marrow involvement. There was a significant trend toward decreasing hyperfiltration after the second cycle of chemotherapy (P = 0.006) and a significant increase in subjects with low GFR (<100 ml/min/1.73 m2) with increasing number of cycles of chemotherapy (P = 0.005). CONCLUSION: Glomerular hyperfiltration is common in children with malignancies at diagnosis and during initial cycles of chemotherapy. It is particularly prevalent in patients with central nervous tumors, which are frequently smaller in volume. Therefore, the pathophysiological mechanism of hyperfiltration cannot be explained solely on the basis of large tumor volume and subsequent cell breakdown. We hypothesize that host hypermetabolic state plays an important role in pathophysiology of hyperfiltration.

Significance of clinical and biologic features in Stage 3 neuroblastoma: a report from the International Neuroblastoma Risk Group project.

BACKGROUND: International Neuroblastoma Staging System (INSS) Stage 3 neuroblastoma is a heterogeneous disease. Data from the International Neuroblastoma Risk Group (INRG) database were analyzed to define patient and tumor characteristics predictive of outcome. PROCEDURE: Of 8,800 patients in the INRG database, 1,483 with INSS Stage 3 neuroblastoma and complete follow-up data were analyzed. Secondary analysis was performed in 1,013 patients (68%) with MYCN-non-amplified (NA) tumors. Significant prognostic factors were identified via log-rank test comparisons of survival curves. Multivariable Cox proportional hazards regression model was used to identify factors independently predictive of event-free survival (EFS). RESULTS: Age at diagnosis (P < 0.0001), tumor MYCN status (P < 0.0001), and poorly differentiating/undifferentiated histology (P = 0.03) were independent predictors of EFS. Compared to other Stage 3 subgroups, outcome was inferior for patients ≥ 547 days with MYCN-NA neuroblastoma (P < 0.0001), and within this cohort, serum ferritin ≥ 96 ng/ml was associated with inferior EFS (P = 0.02). For patients <547 days of age with MYCN-NA tumors, serum ferritin levels were prognostic of overall survival (OS) (P = 0.04) and chromosome 11q aberration was prognostic of EFS (P = 0.03). CONCLUSIONS: Among patients with INSS Stage 3 neuroblastoma patients, age at diagnosis, MYCN status and histology predict outcome. Patients <547 days of age with MYCN-NA tumors that lack chromosome 11q aberrations or those with serum ferritin <96 ng/ml have excellent prognosis and should be considered for therapy reduction. Prospective clinical trials are needed to identify optimal therapy for those patients ≥ 547 days of age with undifferentiated histology or elevated serum ferritin.

Epithelioid Sarcoma in a Young Child: A Case Report and Literature Review.

Epithelioid sarcoma is a rare, high-grade malignant soft tissue tumor that is often misdiagnosed. Classified as a mesenchymal malignancy, it exhibits both mesenchymal and epithelial markers. Occurrence in children under age 10 is extremely rare. This report describes the clinical course and management of a 5-year-old girl who presented with epithelioid sarcoma in the distal extremity. The lesion was initially misdiagnosed and treated for over a year as a common wart.

Clinical outcome in children with recurrent neuroblastoma treated with ABT-751 and effect of ABT-751 on proliferation of neuroblastoma cell lines and on tubulin polymerization in vitro.

BACKGROUND: ABT-751, an orally bioavailable sulfonamide, binds beta-tubulin to inhibit microtubule polymerization. We described response and event-free survival (EFS) in children with neuroblastoma and other solid tumors receiving ABT-751, assessed in vitro cytotoxicity of ABT-751 and evaluated the effect of ABT-751 on tubulin polymerization in peripheral blood mononuclear cells (PBMC) and pediatric tumor cell lines. PROCEDURE: Patients with neuroblastoma (n = 50) or other solid tumors (n = 26) enrolled on the ABT-751 pediatric phase I and pilot trials were reviewed. The sulforhodamine B (SRB) and ACEA Real-Time Cell Electronic Sensing (RT-CES) assays were used to determine the in vitro cytotoxicity. Pharmacodynamic effects on tubulin polymerization/depolymerization were assessed by Western blot and confocal microscopy using antibodies specific for post-translational modifications of polymerized tubulin. RESULTS: Forty-five patients with neuroblastoma were evaluated for anti-tumor response. No complete or partial responses were documented. The median EFS was 9.3 weeks for children with neuroblastoma and 3.3 weeks for children other solid tumors (P < 0.0001). The ABT-751 IC(50) was 0.6-2.6 mcM in neuroblastoma and 0.7-4.6 mcM in other solid tumor cell lines. Following drug exposure, polymerized tubulin decreased in a concentration- and time-dependent manner in cell lines. CONCLUSIONS: In children treated with ABT-751, the EFS is longer in children with neuroblastoma as compared to other diagnoses. In vitro, ABT-751 was cytotoxic at concentrations tolerable in children. Effects of ABT-751 on polymerization and microtubule structure were time- and dose-dependent but not dependent on tumor type.

Non-High-Risk Neuroblastoma: Classification and Achievements in Therapy.

Neuroblastoma, a tumor of the sympathetic nervous system, is the most common extra-cranial neoplasm of childhood. Variables with prognostic significance in patients with neuroblastoma, including age at diagnosis, disease stage, tumor histology, MYCN gene amplification, tumor cell ploidy, and the presence of segmental chromosomal aberrations are utilized to classify patients based on risk of disease recurrence. Patients with non-high-risk neuroblastoma, low- and intermediate-risk categories, represent nearly half of all newly diagnosed cases. This group has an excellent event-free and overall survival with current therapy. Over time, the objective in treatment of non-high-risk neuroblastoma has been reduction of therapy intensity to minimize short- and long-term adverse events all the while maintaining excellent outcomes.

Defining Risk Factors for Chemotherapeutic Intervention in Infants With Stage 4S Neuroblastoma: A Report From Children's Oncology Group Study ANBL0531.

PURPOSE: Infants with stage 4S neuroblastoma usually have favorable outcomes with observation or minimal chemotherapy. However, young infants with symptoms secondary to massive hepatomegaly or with unfavorable tumor biology are at high risk of death. Our aim was to improve outcomes for patients with symptomatic and/or unfavorable biology 4S neuroblastoma with a uniform treatment approach using a biology- and response-based algorithm. PATIENTS AND METHODS: The subset of patients with 4S disease with MYCN-not amplified tumors with impaired or impending organ dysfunction, or with unfavorable histology and/or diploid DNA index, were eligible. Patients were assigned to receive two, four, or eight cycles of chemotherapy on the basis of histology, diploid DNA index, chromosome arm 1p or 11q loss of heterozygosity (LOH) status, and symptoms. RESULTS: Forty-nine eligible patients were enrolled: 41 were symptomatic and 28 had unfavorable biology. Seventeen patients (symptomatic, favorable biology) were assigned two cycles, 21 patients (any unfavorable biologic feature without 1p or 11q LOH) were assigned four cycles, and 11 patients (unfavorable biology including 1p and/or 11q LOH [n = 7] or symptomatic with unknown biology [n = 4]), were assigned eight cycles. The 3-year overall survival was 81.4% ± 5.8%. Eight of nine deaths were in patients younger than 2 months of age at diagnosis (median, 9 days [range, 1 to 68 days]): five acute deaths were a result of hepatomegaly and associated toxicities; two were a result of late relapse in patients with unfavorable biology; and two were a result of treatment complications. No deaths occurred after protocol-mandated pre-emptive treatment of infants younger than 2 months with hepatomegaly, regardless of symptoms. A new scoring algorithm for emergent chemotherapy in patients with 4S disease was developed on the basis of this experience. CONCLUSION: The outcome for 4S neuroblastoma can be improved with pre-emptive chemotherapy for evolving hepatomegaly or other baseline comorbidities in infants younger than 2 months of age.

Immunotherapy of Relapsed and Refractory Solid Tumors With Ex Vivo Expanded Multi-Tumor Associated Antigen Specific Cytotoxic T Lymphocytes: A Phase I Study.

PURPOSE: Tumor-associated antigen cytotoxic T cells (TAA-Ts) represent a new, potentially effective and nontoxic therapeutic approach for patients with relapsed or refractory solid tumors. In this first-in-human trial, we investigated the safety of administering TAA-Ts that target Wilms tumor gene 1, preferentially expressed antigen of melanoma, and survivin to patients with relapsed/refractory solid tumors. MATERIALS AND METHODS: TAA-T products were generated from autologous peripheral blood and infused over three dose levels: 1, 2, and 4 × 107 cells/m2. Patients were eligible for up to eight infusions administered 4 to 7 weeks apart. We assessed dose limiting toxicity during the first 45 days after infusion. Disease response was determined within the context of a phase I trial. RESULTS: There were no dose-limiting toxicities. Of 15 evaluable patients, 11 (73%) with stable disease or better at day 45 postinfusion were defined as responders. Six responders remain without progression at a median of 13.9 months (range, 4.1 to 19.9 months) after initial TAA-Ts. Patients who were treated at the highest dose level showed the best clinical outcomes, with a 6-month progression-free survival of 73% after TAA-T infusion compared with a 38% 6-month progression-free survival with prior therapy. Antigen spreading and a reduction in circulating tumor-associated antigens using digital droplet polymerase chain reaction was observed in patients after TAA-T infusion. CONCLUSION: TAA-Ts safely induced disease stabilization, prolonged time to progression, and were associated with antigen spreading and a reduction in circulating tumor-associated antigen DNA levels in patients with relapsed/refractory solid tumors without lymphodepleting chemotherapy before infusion. TAA-Ts are a promising new treatment approach for patients with solid tumors.

The plasma and cerebrospinal fluid pharmacokinetics of erlotinib and its active metabolite (OSI-420) after intravenous administration of erlotinib in non-human primates.

PURPOSE: Erlotinib hydrochloride is a small molecule inhibitor of epidermal growth factor receptor (EGFR). EGFR is over-expressed in primary brain tumors and solid tumors that metastasize to the central nervous system. We evaluated the plasma and cerebrospinal fluid (CSF) pharmacokinetics of erlotinib and its active metabolite OSI-420 after an intravenous (IV) dose in a non-human primate model. METHODS: Erlotinib was administered as a 1 h IV infusion to four adult rhesus monkeys. Serial blood and CSF samples were drawn over 48 h and erlotinib and OSI-420 were quantified with an HPLC/tandem mass spectroscopic assay. Pharmacokinetic parameters were estimated using non-compartmental and compartmental methods. CSF penetration was calculated from the AUC(CSF):AUC(plasma). RESULTS: Erlotinib disappearance from plasma after a short IV infusion was biexponential with a mean terminal half-life of 5.2 h and a mean clearance of 128 ml/min per m(2). OSI-420 exposure (AUC) in plasma was 30% (range 12-59%) of erlotinib, and OSI-420 clearance was more than 5-fold higher than erlotinib. Erlotinib and OSI-420 were detectable in CSF. The CSF penetration (AUC(CSF):AUC(plasma)) of erlotinib and OSI-420 was <5% relative to total plasma concentration, but CSF drug exposure was approximately 30% of plasma free drug exposure, which was calculated from published plasma protein binding values. The IV administration of erlotinib was well tolerated. CONCLUSIONS: Erlotinib and its active metabolite OSI-420 are measurable in CSF after an IV dose. The drug exposure (AUC) in the CSF is limited relative to total plasma concentrations but is substantial relative the free drug exposure in plasma.

Feasibility Study of a Novel Experimental Induction Protocol Combining B43-PAP (Anti-CD19) Immunotoxin With Standard Induction Chemotherapy in Children and Adolescents With Relapsed B-Lineage ALL: A Report From the Children's Oncology Group.

BACKGROUND: B43-pokeweed antiviral protein (B43-PAP) is a high-affinity anti-CD19 immunotoxin that is capable of causing apoptotic death in B-lineage leukemic cells with a drug-resistant phenotype. B43-PAP exhibited in vivo antileukemic activity in preclinical studies as well as on a single-agent phase I clinical trial. This pediatric phase I/II study evaluated the toxicity profile and efficacy of B43-PAP immunotoxin in combination with standard induction chemotherapy in children and adolescents with relapsed CD19-positive B-lineage acute lymphoblastic leukemia (B-ALL). Pharmacokinetic profile and immunogenicity of B43-PAP were assessed. EXPERIMENTAL DESIGN: B43-PAP in combination with standard 3 and 4-drug induction chemotherapy was administered on days 9-13 and 21-25 of a 28-day treatment course with vincristine, prednisone, L-asparaginase, daunomycin, and intrathecal methotrexate. Thirty patients with relapsed B-ALL were enrolled on study CCG-0957. RESULTS: Grade III/IV nonhematologic dose-limiting toxicities were encountered in 4 patients evaluable for toxicity and included myalgias, motor dysfunction, pulmonary toxicity, and elevated liver transaminase. Dose-limiting toxicities occurred only with the 4-drug regimen. Fourteen patients achieved a complete remission at the end of induction among the 20 patients evaluable for response. CONCLUSIONS: B43-PAP in combination with standard induction chemotherapy can be safely administered and exhibits clinical antileukemic activity against relapsed B-ALL.

Pharmacokinetics of temozolomide administered in combination with O6-benzylguanine in children and adolescents with refractory solid tumors.

PURPOSE: Temozolomide pharmacokinetics were evaluated in children receiving concurrent O(6)-benzylguanine (O(6)BG), which enhanced the hematological toxicity of temozolomide. METHODS: Temozolomide was administered orally, daily for 5 days starting at 28 mg/m(2) per day with escalations to 40, 55, 75 and 100 mg/m(2) per day with O(6)BG intravenously daily for 5 days at doses of 60, 90 or 120 mg/m(2) per day. Plasma samples were drawn over 48 h after the day 5 dose. Temozolomide was quantified with a validated HPLC/tandem mass spectroscopic assay. RESULTS: Temozolomide was rapidly absorbed (mean T (max), 2.1 h). The mean apparent clearance (CL/F) (96 mL/min/m(2)) was similar to the CL/F for temozolomide alone and was not age- or gender-dependent. There was minimal inter-patient variability. CONCLUSIONS: The enhanced hematologic toxicity resulting from combining O(6)BG with temozolomide does not appear to be the result of a pharmacokinetic interaction between the agents.

Phase 2 trial of recombinant tumor necrosis factor-alpha in combination with dactinomycin in children with recurrent Wilms tumor.

Tumor necrosis factor (TNF), a peptide produced by macrophages with cytostatic and cytolytic effects, demonstrated single agent antitumor activity and synergistic effect when administered with dactinomycin in in vitro tumor cell lines, in vivo xenograft models, and adult and pediatric phase 1 clinical trials. This phase 2 pediatric trial evaluated the efficacy and further defined the toxicity profile of recombinant TNF (rTNF) and dactinomycin in patients with recurrent or refractory Wilms tumor. On this 2 stage Children's Cancer Group trial, dactinomycin (15 microg/kg/d, IV) immediately followed by rTNF (200 microg/m/d, IV), once daily for 5 consecutive days, was administered to patients with recurrent or refractory Wilms tumor. Cycles repeated every 21 days to a maximum of 12 courses. Nineteen of 21 consecutive patients, ranging 0.9 to 16.5 years of age at the time of initial diagnosis, were evaluable for response and toxicity. Three patients (15.8%) had a complete response, 5 (26.3%) had stable disease, and 11 (57.9%) had progressive disease. Following 59 patient treatment cycles, the most commonly observed grade 3/4 toxicities were thrombocytopenia (40.7%), elevated liver transaminases (23.7%), neutropenia (20.3%), leucopenia (13.6%), anemia (11.9%), and myalgias (10.2%). Before completion of stage 2, the study closed due to unavailability of rTNF. The documented complete responses and disease stabilization suggest antitumor activity of rTNF with dactinomycin in patients with recurrent Wilms tumor. The combination was well tolerated. Although grade 3/4 adverse events were reported, dose adjustments were not required. Toxicities resolved without significant interventions.

Utility of PET scans to predict disease relapse in pediatric patients with Hodgkin lymphoma.

BACKGROUND: Positron emission tomography (PET) differentiates normal from abnormal cells based on metabolic activity. Numerous studies report that PET scan offers increased sensitivity, specificity and predictive values as compared to computed tomography (CT) in adult lymphoma patients. PROCEDURE: Twenty-three consecutive pediatric Hodgkin lymphoma (HL) patients were evaluated with PET scan either at diagnosis or during treatment, then at therapy completion and in follow-up. RESULTS: Twenty two of the 23 patients had a negative PET scan at the end of therapy; however, ten later developed a positive scan for a total of 11 (47.8%) patients with a positive post treatment PET scan. Six tissue biopsies were performed in five patients; four specimens were negative for disease and two confirmed HL relapse. Six patients were monitored clinically and remained asymptomatic; four had resolution of abnormalities on repeat PET while two had persistently positive, but stable PET scan findings and continue to be in remission at 11 and 40 months following treatment. Twelve (52.2%) patients of the original cohort have had consistently negative PET scans and have not relapsed. CONCLUSIONS: PET is a sensitive (100%), but not a specific (57.1%) method for evaluating post-treatment pediatric HL patients with a strong negative predictive value (NPV; 100%), but poor positive predictive value (PPV; 18.2%). We do not recommend treatment decisions be based solely on PET scan results.