Julia L. Glade Bender

Phase I Trial and Pharmacokinetic Study of Bevacizumab in Pediatric Patients With Refractory Solid Tumors: A Children's Oncology Group Study

PURPOSE We conducted a pediatric phase I trial of the vascular endothelial growth factor (VEGF)-neutralizing antibody bevacizumab (BV). Primary aims included estimating the maximum-tolerated dose (MTD) and determining the dose-limiting toxicities (DLTs), pharmacokinetics, and biologic effects of BV in children with cancer. PATIENTS AND METHODS BV (5, 10, 15 mg/kg) was administered intravenously every 2 weeks in 28-day courses to children with refractory solid tumors. RESULTS Twenty-one patients enrolled, 20 (median age, 13 years) were eligible, and 18 completed one course and were fully assessable for toxicity. A total of 67 courses were administered (median, three courses per patient; range, one to 16 courses). Treatment was well tolerated with no DLTs observed. Non-DLTs included infusional reaction, rash, mucositis, proteinuria, and lymphopenia. Increases in systolic and diastolic blood pressure not meeting Common Terminology Criteria for Adverse Events (CTCAEv3) pediatric-specific criteria for hypertension were observed. There was no hemorrhage or thrombosis. Growth perturbation was not detected in a limited sample over the first course. The serum exposure to BV as measured by area under the concentration-time curve (AUC) seemed to increase in proportion to dose. The median clearance of BV was 4.1 mL/d/kg (range, 3.1 to 15.5 mL/d/kg), and the median half-life was 11.8 days (range, 4.4 to 14.6 days). No objective responses were observed. Exploratory analyses on circulating endothelial mobilization and viability are consistent with the available adult data. CONCLUSION BV is well tolerated in children. Phase II pediatric studies of BV in combination with chemotherapy in dosing schedules similar to adults are planned.

Phase I Pharmacokinetic and Pharmacodynamic Study of Pazopanib in Children With Soft Tissue Sarcoma and Other Refractory Solid Tumors: A Children's Oncology Group Phase I Consortium Report

PURPOSE Pazopanib, an oral multikinase angiogenesis inhibitor, prolongs progression-free survival in adults with soft tissue sarcoma (STS). A phase I pharmacokinetic and pharmacodynamic study of two formulations of pazopanib was performed in children with STS or other refractory solid tumors. PATIENTS AND METHODS Pazopanib (tablet formulation) was administered once daily in 28-day cycles at four dose levels (275 to 600 mg/m(2)) using the rolling-six design. Dose determination for a powder suspension was initiated at 50% of the maximum-tolerated dose (MTD) for the intact tablet. Ten patients with STS underwent dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) scanning at baseline and 15 ± 2 days after initiation of pazopanib at the tablet MTD. RESULTS Fifty-three patients were enrolled; 51 were eligible (26 males; median age, 12.9 years; range, 3.8 to 23.9 years). Hematologic and nonhematologic toxicities were generally mild, with dose-limiting lipase, amylase, and ALT elevation, proteinuria, and hypertension. One patient with occult brain metastasis had grade 4 intracranial hemorrhage. The MTD was 450 mg/m(2) for tablet and 160 mg/m(2) for suspension. Steady-state trough concentrations were reached by day 15 and did not seem to be dose dependent. One patient each with hepatoblastoma or desmoplastic small round cell tumor achieved a partial response; eight patients had stable disease for ≥ six cycles, seven of whom had sarcoma. All patients with evaluable DCE-MRI (n = 8) experienced decreases in tumor blood volume and permeability (P < .01). Placental growth factor increased, whereas endoglin and soluble vascular endothelial growth factor receptor-2 decreased (P < .01; n = 41). CONCLUSION Pazopanib is well tolerated in children, with evidence of antiangiogenic effect and potential clinical benefit in pediatric sarcoma.

A Phase I Trial and Pharmacokinetic Study of Sorafenib in Children with Refractory Solid Tumors or Leukemias: A Children's Oncology Group Phase I Consortium Report

Purpose To determine the dose-limiting toxicities (DLT), maximum tolerated dose (MTD), pharmacokinetics and pharmacodynamics of sorafenib in children with refractory extracranial solid tumors and evaluate the tolerability of the solid tumor MTD in children with refractory leukemias. Experimental Design Sorafenib was administered orally q12h for consecutive 28 day cycles. Pharmacokinetics (day 1 and steady state) and pharmacodynamics were performed during cycle 1. Results Of sixty-five patients enrolled, 60 were eligible. In the solid tumor cohort (n=49), 4/6 patients experienced a DLT (hypertension, pain, rash/urticaria, thrombocytopenia, ALT/AST) at the starting dose (150 mg/m2/dose) which resulted in de-escalation to 105 mg/m2/dose. After eligibility criteria modification and dose re-escalation, the MTD was 200 mg/m2/dose for solid tumors and 150 mg/m2/dose for leukemias. Sorafenib exposure was highly variable between patients, but was within the ranges reported in adults. The apparent sorafenib clearance increased with patient age. Diarrhea, rash, fatigue, and increased ALT/AST were the most common sorafenib-related toxicities. Stable disease for ≥ 4 cycles was observed in 14 solid tumor patients, and two patients with acute myeloid leukemia and FLT3 internal tandem duplication experienced a decrease in bone marrow blasts toPurpose: To determine the dose-limiting toxicities (DLT), maximum tolerated dose (MTD), pharmacokinetics, and pharmacodynamics of sorafenib in children with refractory extracranial solid tumors and evaluate the tolerability of the solid tumor MTD in children with refractory leukemias. Experimental Design: Sorafenib was administered orally every 12 hours for consecutive 28-day cycles. Pharmacokinetics (day 1 and steady-state) and pharmacodynamics were conducted during cycle 1. Results: Of 65 patients enrolled, 60 were eligible. In the solid tumor cohort (n = 49), 4 of 6 patients experienced a DLT [hypertension, pain, rash/urticaria, thrombocytopenia, alanine aminotransferase (ALT)/aspartate aminotransferase (AST)] at the starting dose (150 mg/m2/dose) which resulted in de-escalation to 105 mg/m2/dose. After eligibility criteria modification and dose re-escalation, the MTD was 200 mg/m2/dose for solid tumors and 150 mg/m2/dose for leukemias. Sorafenib exposure was highly variable between patients but was within the ranges reported in adults. The apparent sorafenib clearance increased with patient age. Diarrhea, rash, fatigue, and increased ALT/AST were the most common sorafenib-related toxicities. Stable disease for 4 or more cycles was observed in 14 solid tumor patients, and 2 patients with acute myeloid leukemia (AML) and FLT3 internal tandem duplication (FLT3ITD) experienced a decrease in bone marrow blasts to less than 5%. Conclusions: The recommended phase II dose of sorafenib administered every 12 hours continuously for children with solid tumors is 200 mg/m2/dose and 150 mg/m2/dose for children with leukemias. Sorafenib toxicities and distribution in children are similar to adults. The activity of sorafenib in children with AML and FLT3ITD is currently being evaluated, and a phase II study for select solid tumors is ongoing. Clin Cancer Res; 18(21); 6011–22. ©2012 AACR.

Multicenter Feasibility Study of Tumor Molecular Profiling to Inform Therapeutic Decisions in Advanced Pediatric Solid Tumors: The Individualized Cancer Therapy (iCat) Study

Importance Pediatric cancers represent a unique case with respect to cancer genomics and precision medicine, as the mutation frequency is low, and targeted therapies are less available. Consequently, it is unknown whether clinical sequencing can be of benefit. Objective To assess the feasibility of identifying actionable alterations and making individualized cancer therapy (iCat) recommendations in pediatric patients with extracranial solid tumors. Design, Setting, and Participants Clinical sequencing study at 4 academic medical centers enrolling patients between September 5, 2012, and November 19, 2013, with 1 year of clinical follow-up. Participants were 30 years or younger with high-risk, recurrent, or refractory extracranial solid tumors. The data analysis was performed October 28, 2014. Interventions Tumor profiling performed on archived clinically acquired specimens consisted of mutation detection by a Sequenom assay or targeted next-generation sequencing and copy number assessment by array comparative genomic hybridization. Results were reviewed by a multidisciplinary expert panel, and iCat recommendations were made if an actionable alteration was present, and an appropriate drug was available. Main Outcomes and Measures Feasibility was assessed using a 2-stage design based on the proportion of patients with recommendations. Results Of 100 participants (60 male; median [range] age, 13.4 [0.8-29.8] years), profiling was technically successful in 89 (89% [95% CI, 83%-95%]). Median (range) follow-up was 6.8 (2.0-23.6) months. Overall, 31 (31% [95% CI, 23%-41%]) patients received an iCat recommendation and 3 received matched therapy. The most common actionable alterations leading to an iCat recommendation were cancer-associated signaling pathway gene mutations (n = 10) and copy number alterations in MYC/MYCN (n = 6) and cell cycle genes (n = 11). Additional alterations with implications for clinical care but not resulting in iCat recommendations were identified, including mutations indicating the possible presence of a cancer predisposition syndrome and translocations suggesting a change in diagnosis. In total, 43 (43% [95% CI, 33%-53%]) participants had results with potential clinical significance. Conclusions and Relevance A multi-institution clinical genomics study in pediatric oncology is feasible and a substantial proportion of relapsed or refractory pediatric solid tumors have actionable alterations. Trial Registration clinicaltrials.gov Identifier: NCT01853345.

Reversible posterior leukoencephalopathy syndrome in a child treated with bevacizumab

Bevacizumab is a monoclonal antibody targeting vascular endothelial growth factor (VEGF). Hypertension is a well‐recognized, common side effect of VEGF blocking agents. The reversible posterior leukoencephalopathy syndrome (RPLS) has been described as a rare but serious consequence of bevacizumab administration. We present a case of a 6‐year‐old child with refractory hepatoblastoma who developed hypertensive crisis, seizures and MRI changes consistent with RPLS while receiving bevacizumab with gemcitabine and oxaliplatin. Findings completely resolved without neurologic sequelae with stringent blood‐pressure control. Better understanding of risk for RPLS, prompt recognition and aggressive management will be required as bevacizumab gains wider use in pediatrics. Pediatr Blood Cancer 2009;52:669–671.

Implementation of next generation sequencing into pediatric hematology-oncology practice: moving beyond actionable alterations

BackgroundMolecular characterization has the potential to advance the management of pediatric cancer and high-risk hematologic disease. The clinical integration of genome sequencing into standard clinical practice has been limited and the potential utility of genome sequencing to identify clinically impactful information beyond targetable alterations has been underestimated.MethodsThe Precision in Pediatric Sequencing (PIPseq) Program at Columbia University Medical Center instituted prospective clinical next generation sequencing (NGS) for pediatric cancer and hematologic disorders at risk for treatment failure. We performed cancer whole exome sequencing (WES) of patient-matched tumor-normal samples and RNA sequencing (RNA-seq) of tumor to identify sequence variants, fusion transcripts, relative gene expression, and copy number variation (CNV). A directed cancer gene panel assay was used when sample adequacy was a concern. Constitutional WES of patients and parents was performed when a constitutionally encoded disease was suspected. Results were initially reviewed by a molecular pathologist and subsequently by a multi-disciplinary molecular tumor board. Clinical reports were issued to the ordering physician and posted to the patient’s electronic medical record.ResultsNGS was performed on tumor and/or normal tissue from 101 high-risk pediatric patients. Potentially actionable alterations were identified in 38% of patients, of which only 16% subsequently received matched therapy. In an additional 38% of patients, the genomic data provided clinically relevant information of diagnostic, prognostic, or pharmacogenomic significance. RNA-seq was clinically impactful in 37/65 patients (57%) providing diagnostic and/or prognostic information for 17 patients (26%) and identified therapeutic targets in 15 patients (23%). Known or likely pathogenic germline alterations were discovered in 18/90 patients (20%) with 14% having germline alternations in cancer predisposition genes. American College of Medical Genetics (ACMG) secondary findings were identified in six patients.ConclusionsOur results demonstrate the feasibility of incorporating clinical NGS into pediatric hematology-oncology practice. Beyond the identification of actionable alterations, the ability to avoid ineffective/inappropriate therapies, make a definitive diagnosis, and identify pharmacogenomic modifiers is clinically impactful. Taking a more inclusive view of potential clinical utility, 66% of cases tested through our program had clinically impactful findings and samples interrogated with both WES and RNA-seq resulted in data that impacted clinical decisions in 75% of cases.

Translating genomic discoveries to the clinic in pediatric oncology.

Purpose of review The present study describes the recent advances in the identification of targetable genomic alterations in pediatric cancers, along with the progress and associated challenges in translating these findings into therapeutic benefit. Recent findings Each field within pediatric cancer has rapidly and comprehensively begun to define genomic targets in tumors that potentially can improve the clinical outcome of patients, including hematologic malignancies (leukemia and lymphoma), solid malignancies (neuroblastoma, rhabdomyosarcoma, Ewing sarcoma, and osteosarcoma), and brain tumors (gliomas, ependymomas, and medulloblastomas). Although each tumor has specific and sometimes overlapping genomic targets, the translation to the clinic of new targeted trials and precision medicine protocols is still in its infancy. The first clinical tumor profiling studies in pediatric oncology have demonstrated feasibility and patient enthusiasm for the personalized medicine paradigm, but have yet to demonstrate clinical utility. Complexities influencing implementation include rapidly evolving sequencing technologies, tumor heterogeneity, and lack of access to targeted therapies. The return of incidental findings from the germline also remains a challenge, with evolving policy statements and accepted standards. Summary The translation of genomic discoveries to the clinic in pediatric oncology continues to move forward at a brisk pace. Early adoption of genomics for tumor classification, risk stratification, and initial trials of targeted therapeutic agents has led to powerful results. As our experience grows in the integration of genomic and clinical medicine, the outcome for children with cancer should continue to improve.

A Phase I Trial and Pharmacokinetic Study of Aflibercept (VEGF Trap) in Children with Refractory Solid Tumors: A Children's Oncology Group Phase I Consortium Report

Purpose: Aflibercept is a novel decoy receptor that efficiently neutralizes circulating VEGF. A pediatric phase I trial was conducted to define the dose-limiting toxicities (DLT), maximum tolerated dose (MTD), and pharmacokinetics (PK) of aflibercept. Experimental Design: Cohorts of three to six children with refractory solid tumors received aflibercept intravenously over 60 minutes every 14 days, at 2.0, 2.5, or 3.0 mg/kg/dose. PK sampling and analysis of peripheral blood biomarkers were conducted with the initial dose. Results: Twenty-one eligible patients were enrolled; 18 were fully evaluable for toxicity. One of six patients receiving 2.0 mg/kg/dose developed dose-limiting intratumoral hemorrhage and two of six receiving 3.0 mg/kg/dose developed either dose-limiting tumor pain or tissue necrosis. None of the six patients receiving 2.5 mg/kg/dose developed DLTs, defining this as the MTD. The most common non-DLTs were hypertension and fatigue. Three patients with hepatocellular carcinoma, hepatoblastoma and clear cell sarcoma had stable disease for >13 weeks. At the MTD, the ratio of free-to-bound aflibercept serum concentration was 2.10 on day 8 but only 0.44 by day 15. A rapid decrease in VEGF (P < 0.05) and increase in placental growth factor (PlGF; P < 0.05) from baseline was observed in response to aflibercept by day 2. Conclusions: The aflibercept MTD in children of 2.5 mg/kg/dose every 14 days is lower than the adult recommended dose of 4.0 mg/kg. This dose achieves, but does not sustain, free aflibercept concentrations in excess of bound. Tumor pain and hemorrhage may be evidence of antitumor activity but were dose-limiting. Clin Cancer Res; 18(18); 5081–9. ©2012 AACR.

Irinotecan–temozolomide with temsirolimus or dinutuximab in children with refractory or relapsed neuroblastoma (COG ANBL1221): an open-label, randomised, phase 2 trial

BACKGROUND Outcomes for children with relapsed and refractory neuroblastoma are dismal. The combination of irinotecan and temozolomide has activity in these patients, and its acceptable toxicity profile makes it an excellent backbone for study of new agents. We aimed to test the addition of temsirolimus or dinutuximab to irinotecan-temozolomide in patients with relapsed or refractory neuroblastoma. METHODS For this open-label, randomised, phase 2 selection design trial of the Childrens Oncology Group (COG; ANBL1221), patients had to have histological verification of neuroblastoma or ganglioneuroblastoma at diagnosis or have tumour cells in bone marrow with increased urinary catecholamine concentrations at diagnosis. Patients of any age were eligible at first designation of relapse or progression, or first designation of refractory disease, provided organ function requirements were met. Patients previously treated for refractory or relapsed disease were ineligible. Computer-based randomisation with sequence generation defined by permuted block randomisation (block size two) was used to randomly assign patients (1:1) to irinotecan and temozolomide plus either temsirolimus or dinutuximab, stratified by disease category, previous exposure to anti-GD2 antibody therapy, and tumour MYCN amplification status. Patients in both groups received oral temozolomide (100 mg/m2 per dose) and intravenous irinotecan (50 mg/m2 per dose) on days 1-5 of 21-day cycles. Patients in the temsirolimus group also received intravenous temsirolimus (35 mg/m2 per dose) on days 1 and 8, whereas those in the dinutuximab group received intravenous dinutuximab (17·5 mg/m2 per day or 25 mg/m2 per day) on days 2-5 plus granulocyte macrophage colony-stimulating factor (250 μg/m2 per dose) subcutaneously on days 6-12. Patients were given up to a maximum of 17 cycles of treatment. The primary endpoint was the proportion of patients achieving an objective (complete or partial) response by central review after six cycles of treatment, analysed by intention to treat. Patients, families, and those administering treatment were aware of group assignment. This study is registered with ClinicalTrials.gov, number NCT01767194, and follow-up of the initial cohort is ongoing. FINDINGS Between Feb 22, 2013, and March 23, 2015, 36 patients from 27 COG member institutions were enrolled on this groupwide study. One patient was ineligible (alanine aminotransferase concentration was above the required range). Of the remaining 35 patients, 18 were randomly assigned to irinotecan-temozolomide-temsirolimus and 17 to irinotecan-temozolomide-dinutuximab. Median follow-up was 1·26 years (IQR 0·68-1·61) among all eligible participants. Of the 18 patients assigned to irinotecan-temozolomide-temsirolimus, one patient (6%; 95% CI 0·0-16·1) achieved a partial response. Of the 17 patients assigned to irinotecan-temozolomide-dinutuximab, nine (53%; 95% CI 29·2-76·7) had objective responses, including four partial responses and five complete responses. The most common grade 3 or worse adverse events in the temsirolimus group were neutropenia (eight [44%] of 18 patients), anaemia (six [33%]), thrombocytopenia (five [28%]), increased alanine aminotransferase (five [28%]), and hypokalaemia (four [22%]). One of the 17 patients assigned to the dinutuximab group refused treatment after randomisation; the most common grade 3 or worse adverse events in the remaining 16 patients evaluable for safety were pain (seven [44%] of 16), hypokalaemia (six [38%]), neutropenia (four [25%]), thrombocytopenia (four [25%]), anaemia (four [25%]), fever and infection (four [25%]), and hypoxia (four [25%]); one patient had grade 4 hypoxia related to therapy that met protocol-defined criteria for unacceptable toxicity. No deaths attributed to protocol therapy occurred. INTERPRETATION Irinotecan-temozolomide-dinutuximab met protocol-defined criteria for selection as the combination meriting further study whereas irinotecan-temozolomide-temsirolimus did not. Irinotecan-temozolomide-dinutuximab shows notable anti-tumour activity in patients with relapsed or refractory neuroblastoma. Further evaluation of biomarkers in a larger cohort of patients might identify those most likely to respond to this chemoimmunotherapeutic regimen. FUNDING National Cancer Institute.

Clinical Development of VEGF Signaling Pathway Inhibitors in Childhood Solid Tumors

Angiogenesis is a target shared by both adult epithelial cancers and the mesenchymal or embryonal tumors of childhood. Development of antiangiogenic agents for the pediatric population has been complicated by largely theoretical concern for toxicities specific to the growing child and prioritization among the many antiangiogenic agents being developed for adults. This review summarizes the mechanism of action and preclinical data relevant to childhood cancers and early-phase clinical trials in childhood solid tumors. Single-agent adverse event profiles in adults and children are reviewed with emphasis on cardiovascular, bone health, and endocrine side effects. In addition, pharmacological factors that may be relevant for prioritizing clinical trials of these agents in children are reviewed. Considerations for further clinical evaluation should include preclinical data, relative potency, efficacy in adults, and the current U.S. Food and Drug Administration approval status. Toxicity profiles of vascular endothelial growth factor (VEGF) signaling pathway inhibitors may be age dependent and ultimately, their utility in the treatment of childhood cancer will require combination with standard cytotoxic drugs or other molecularly targeted agents. In combination studies, toxicity profiles, potential drug interactions, and late effects must be considered. Studies to assess the long-term impact of VEGF signaling pathway inhibitors on cardiovascular, endocrine, and bone health in children with cancer are imperative if these agents are to be administered to growing children and adolescents with newly diagnosed cancers.