Phase I Trial of GD2.CART Cells Augmented With Constitutive Interleukin-7 Receptor for Treatment of High-Grade Pediatric CNS Tumors.

PURPOSE: T cells modified with chimeric antigen receptors (CARTs) have demonstrated efficacy for hematologic malignancies; however, benefit for patients with CNS tumors has been limited. To enhance T cell activity against GD2+ CNS malignancies, we modified GD2-directed CART cells (GD2.CARTs) with a constitutively active interleukin (IL)-7 receptor (C7R-GD2.CARTs). METHODS: Patients age 1-21 years with H3K27-altered diffuse midline glioma (DMG) or other recurrent GD2-expressing CNS tumors were eligible for this phase I trial (ClinicalTrials.gov identifier: NCT04099797). All subjects received standard-of-care adjuvant radiation therapy or chemotherapy before study enrollment. The first treatment cohort received GD2.CARTs alone (1 × 107 cells/m2), and subsequent cohorts received C7R-GD2.CARTs at two dose levels (1 × 107 cells/m2; 3 × 107 cells/m2). Standard lymphodepletion with cyclophosphamide and fludarabine was included at all dose levels. RESULTS: Eleven patients (age 4-18 years) received therapy without dose-limiting toxicity. The GD2.CART cohort did not experience toxicity, but had disease progression after brief improvement of residual neurologic deficits (≤3 weeks). The C7R-GD2.CART cohort developed grade 1 tumor inflammation-associated neurotoxicity in seven of eight (88%) cases, controllable with anakinra. Cytokine release syndrome was observed in six of eight (75%, grade 1 in all but one patient) and associated with increased circulating IL-6 and IP-10 (P < .05). Patients receiving C7R-GD2.CARTs experienced temporary improvement from baseline neurologic deficits (range, 2 to >12 months), and seven of eight (88%) remained eligible for additional treatment cycles (range 2-4 cycles). Partial responses by iRANO criteria were observed in two of seven (29%) patients with DMG treated by C7R-GD2.CARTs. CONCLUSION: Intravenous GD2.CARTs with and without C7R were well tolerated. Patients treated with C7R-GD2.CARTs exhibited transient improvement of neurologic deficits and increased circulating cytokines/chemokines. Treatment with C7R-GD2.CARTs represents a novel approach warranting further investigation for children with these incurable CNS cancers.

Phase I/II trial of vorinostat and radiation and maintenance vorinostat in children with diffuse intrinsic pontine glioma: A Children's Oncology Group report.

BACKGROUND: A phase I/II trial of vorinostat (suberoylanilide hydroxamic acid), an oral histone deacetylase inhibitor, was conducted in children with newly diagnosed diffuse intrinsic pontine glioma (DIPG) through the Children's Oncology Group (COG) to: 1) determine the recommended phase II dose (RP2D) of vorinostat given concurrently with radiation therapy; 2) document the toxicities of continuing vorinostat as maintenance therapy after radiation; and 3) to determine the efficacy of this regimen by comparing the risk of progression or death with a historical model from past COG trials. METHODS: Vorinostat was given once daily, Monday through Friday, during radiation therapy (54 Gy in 30 fractions), and then continued at 230 mg/m2 daily for a maximum of twelve 28-day cycles. RESULTS: Twelve patients enrolled in the phase I study; the RP2D of vorinostat given concurrently with radiation was 230 mg/m2/day, Monday through Friday weekly. The six patients enrolled at the RP2D and an additional 64 patients enrolled in the phase II study contributed to the efficacy assessment. Although vorinostat was well-tolerated, did not interrupt radiation therapy, and was permanently discontinued in only 8.6% of patients due to toxicities, risk for EFS-event was not significantly reduced compared with the target risk derived from historical COG data (P = 0.32; 1-sided). The 1-year EFS was 5.85% (95% CI 1.89-13.1%) and 1-year OS was 39.2% (27.8-50.5%). CONCLUSIONS: Vorinostat given concurrently with radiation followed by vorinostat monotherapy was well tolerated in children with newly diagnosed DIPG but failed to improve outcome.

COVID-19 outcomes in a large pediatric hematology-oncology center in Houston, Texas.

An understanding of the behavior of SARS-CoV-2 in pediatric hematology-oncology patients is essential to the optimal management of these patients during the COVID-19 pandemic. This study describes the characteristics and outcomes of COVID-19 disease in children with cancer or hematologic disorders treated at a large children's hospital. A retrospective cohort study was conducted at Texas Children's Cancer and Hematology Center from January 1, 2020 to September 30, 2020. All patients with a primary hematology-oncology diagnosis and SARS-CoV-2 positivity by reverse transcription polymerase chain reaction were identified. Clinical and laboratory data were obtained from the medical record. Descriptive analyses were performed to evaluate COVID-19-related outcomes and risk factors for severe disease in this population. We identified 109 patients with COVID-19 disease, including 52 hematology, 51 oncology, and 6 HSCT patients; median age was 10.3 years (IQR 4.4-15.9), and 58.7% were male. Seventy-four percent of the patients were managed in the outpatient setting. Patients with sickle cell disease were more likely to require hospitalization. ICU care was needed in 8% (n = 9) of the entire cohort, and mechanical ventilation was required in 6.4% (6 oncology patients, 1 hematology patient). COVID-19 contributed to the deaths of two cancer patients. No deaths occurred in hematology or HSCT patients. In conclusion, the risk of severe COVID-19 complications is slightly higher in pediatric hematology-oncology patients than in the general pediatric population but lower than initially feared. For most asymptomatic patients, primary disease management may continue as planned, but treatment decisions must be individualized.

ZFTA-RELA Dictates Oncogenic Transcriptional Programs to Drive Aggressive Supratentorial Ependymoma.

More than 60% of supratentorial ependymomas harbor a ZFTA-RELA (ZRfus) gene fusion (formerly C11orf95-RELA). To study the biology of ZRfus, we developed an autochthonous mouse tumor model using in utero electroporation (IUE) of the embryonic mouse brain. Integrative epigenomic and transcriptomic mapping was performed on IUE-driven ZRfus tumors by CUT&RUN, chromatin immunoprecipitation sequencing, assay for transposase-accessible chromatin sequencing, and RNA sequencing and compared with human ZRfus-driven ependymoma. In addition to direct canonical NFκB pathway activation, ZRfus dictates a neoplastic transcriptional program and binds to thousands of unique sites across the genome that are enriched with PLAGL family transcription factor (TF) motifs. ZRfus activates gene expression programs through recruitment of transcriptional coactivators (Brd4, Ep300, Cbp, Pol2) that are amenable to pharmacologic inhibition. Downstream ZRfus target genes converge on developmental programs marked by PLAGL TF proteins, and activate neoplastic programs enriched in Mapk, focal adhesion, and gene imprinting networks. SIGNIFICANCE: Ependymomas are aggressive brain tumors. Although drivers of supratentorial ependymoma (ZFTA- and YAP1-associated gene fusions) have been discovered, their functions remain unclear. Our study investigates the biology of ZFTA-RELA-driven ependymoma, specifically mechanisms of transcriptional deregulation and direct downstream gene networks that may be leveraged for potential therapeutic testing.This article is highlighted in the In This Issue feature, p. 2113.

Activity of Crizotinib in Patients with ALK-Aberrant Relapsed/Refractory Neuroblastoma: A Children's Oncology Group Study (ADVL0912).

PURPOSE: Anaplastic lymphoma kinase (ALK) aberrations are a promising target for patients with neuroblastoma. We assessed the activity of first-generation ALK inhibitor crizotinib in patients with no known curative treatments and whose tumors harbored an activating ALK alteration. PATIENTS AND METHODS: Twenty patients with relapsed/refractory ALK-positive neuroblastoma received crizotinib at the recommended phase II dose of 280 mg/m2/dose. A Simon two-stage design was used to evaluate the antitumor activity of crizotinib monotherapy. Response evaluation occurred after cycles 1, 3, 5, 7, and then every 3 cycles. Correlation of ALK status and response was a secondary aim of the study. RESULTS: The objective response rate for patients with neuroblastoma was 15% [95% confidence interval (CI): 3.3%-34.3%]: two with partial responses and 1 with a complete response. All three patients had a somatic ALK Arg1275Gln mutation, the most common ALK hotspot mutation observed in neuroblastoma and the only mutation predicted to be sensitive to ALK inhibition with crizotinib. Two patients had prolonged stable disease (10 and 13 cycles, respectively); both harbored an ALK Arg1275Gln mutation. Three patients with ALK Phe1174Leu mutations progressed during cycle 1 of therapy, and one patient with an ALK Phe1174Val received three cycles before disease progression. The two patients with ALK amplification had no response. The most common adverse event was a decrease in neutrophil count. CONCLUSIONS: Despite limited activity seen in this trial, we conclude that this is more likely due to an inability to reach the higher concentrations of crizotinib needed to overcome the competing ATP affinity.See related commentary by Schulte and Eggert, p. 3507.

Safety, tolerability and pharmacokinetics of crizotinib in combination with cytotoxic chemotherapy for pediatric patients with refractory solid tumors or anaplastic large cell lymphoma (ALCL): a Children's Oncology Group phase 1 consortium study (ADVL1212).

PURPOSE: This phase 1 study aimed to determine the safety, tolerability and recommended phase 2 dose (RP2D) of crizotinib in combination with cytotoxic chemotherapy for children with refractory solid tumors and ALCL. METHODS: Pediatric patients with treatment refractory solid tumors or ALCL were eligible. Using a 3 + 3 design, crizotinib was escalated in three dose levels: 165, 215, or 280 mg/m2/dose BID. In Part A, patients received crizotinib oral solution (OS) in combination with topotecan and cyclophosphamide (topo/cyclo); in Part B, crizotinib OS was administered with vincristine and doxorubicin (vcr/dox). In Parts C and D, patients received topo/cyclo in combination with either crizotinib-formulated capsules (FC) or microspheres (cMS), respectively. Crizotinib pharmacokinetic evaluation was required. RESULTS: Forty-four eligible patients were enrolled, 39 were evaluable for toxicity. Parts A and B were terminated due to concerns regarding palatability and tolerability of the OS. In Part C, crizotinib, FC 215 mg/m2/dose BID, in combination with topo/cyclo was tolerated. In Part D, the maximum tolerated dose (MTD) was exceeded at 165 mg/m2/dose of crizotinib cMS. Pharmacokinetics of crizotinib in combination with chemotherapy was similar to single-agent crizotinib and exposures were not formulation dependent. CONCLUSIONS: The RP2D of crizotinib FCs in combination with cyclophosphamide and topotecan was 215 mg/m2/dose BID. The oral solution of crizotinib was not palatable in this patient population. Crizotinib cMS was palatable; however, patients experienced increased toxicity that was not explained by the relative bioavailability or exposure and warrants further investigation. CLINICAL TRIAL REGISTRY: The trial is registered as NCT01606878 at Clinicaltrials.gov.

A phase 2 study of valproic acid and radiation, followed by maintenance valproic acid and bevacizumab in children with newly diagnosed diffuse intrinsic pontine glioma or high-grade glioma.

PURPOSE: To study the efficacy and tolerability of valproic acid (VPA) and radiation, followed by VPA and bevacizumab in children with newly diagnosed diffuse intrinsic pontine glioma (DIPG) or high-grade glioma (HGG). METHODS: Children 3 to 21 years of age received radiation therapy and VPA at 15 mg/kg/day and dose adjusted to maintain a trough range of 85 to 115 µg/mL. VPA was continued post-radiation, and bevacizumab was started at 10 mg/kg intravenously biweekly, four weeks after completing radiation therapy. RESULTS: From September 2009 through August 2015, 20 DIPG and 18 HGG patients were enrolled (NCT00879437). During radiation and VPA, grade 3 or higher toxicities requiring discontinuation or modification of VPA dosing included grade 3 thrombocytopenia (1), grade 3 weight gain (1), and grade 3 pancreatitis (1). During VPA and bevacizumab, the most common grade 3 or higher toxicities were grade 3 neutropenia (3), grade 3 thrombocytopenia (3), grade 3 fatigue (3), and grade 3 hypertension (4). Two patients discontinued protocol therapy prior to disease progression (one grade 4 thrombosis and one grade 1 intratumoral hemorrhage). Median event-free survival (EFS) and overall survival (OS) for DIPG were 7.8 (95% CI 5.6-8.2) and 10.3 (7.4-13.4) months, and estimated one-year EFS was 12% (2%-31%). Median EFS and OS for HGG were 9.1 (6.4-11) and 12.1 (10-22.1) months, and estimated one-year EFS was 24% (7%-45%). Four patients with glioblastoma and mismatch-repair deficiency syndrome had EFS of 28.5, 16.7, 10.4, and 9 months. CONCLUSION: Addition of VPA and bevacizumab to radiation was well tolerated but did not appear to improve EFS or OS in children with DIPG or HGG.

A phase I/II study of veliparib (ABT-888) with radiation and temozolomide in newly diagnosed diffuse pontine glioma: a Pediatric Brain Tumor Consortium study.

BACKGROUND: A Pediatric Brain Tumor Consortium (PBTC) phase I/II trial of veliparib and radiation followed by veliparib and temozolomide (TMZ) was conducted in children with newly diagnosed diffuse intrinsic pontine glioma (DIPG). The objectives were to: (i) estimate the recommended phase II dose (RP2D) of veliparib with concurrent radiation; (ii) evaluate the pharmacokinetic parameters of veliparib during radiation; (iii) evaluate feasibility of intrapatient TMZ dose escalation; (iv) describe toxicities of protocol therapy; and (v) estimate the overall survival distribution compared with historical series. METHODS: Veliparib was given Monday through Friday b.i.d. during radiation followed by a 4-week rest. Patients then received veliparib at 25 mg/m2 b.i.d. and TMZ 135 mg/m2 daily for 5 days every 28 days. Intrapatient dose escalation of TMZ was investigated for patients experiencing minimal toxicity. RESULTS: Sixty-six patients (65 eligible) were enrolled. The RP2D of veliparib was 65 mg/m2 b.i.d. with radiation. Dose-limiting toxicities during radiation with veliparib therapy included: grade 2 intratumoral hemorrhage (n = 1), grade 3 maculopapular rash (n = 2), and grade 3 nervous system disorder (generalized neurologic deterioration) (n = 1). Intrapatient TMZ dose escalation during maintenance was not tolerated. Following a planned interim analysis, it was concluded that this treatment did not show a survival benefit compared with PBTC historical controls, and accrual was stopped for futility. The 1- and 2-year overall survival rates were 37.2% (SE 7%) and 5.3% (SE 3%), respectively. CONCLUSION: Addition of veliparib to radiation followed by TMZ and veliparib was tolerated but did not improve survival for patients with newly diagnosed DIPG. TRIAL REGISTRATION: NCT01514201.

Phase 1/2 trial of talazoparib in combination with temozolomide in children and adolescents with refractory/recurrent solid tumors including Ewing sarcoma: A Children's Oncology Group Phase 1 Consortium study (ADVL1411).

PURPOSE: We conducted a phase 1/2 trial of the poly(ADP-ribose) polymerase 1/2 inhibitor talazoparib in combination with low-dose temozolomide (TMZ) to determine the dose-limiting toxicities (DLTs), recommended phase 2 dose (RP2D), and pharmacokinetics of this combination in children with recurrent/refractory solid tumors; and to explore clinical activity in Ewing sarcoma (EWS) (NCT02116777). METHODS: Talazoparib (400-600 µg/m2 /dose, maximum daily dose 800-1000 µg) was administered q.d. or b.i.d. orally on day 1 followed by q.d. dosing concomitant with q.d. dosing of oral TMZ (20-55 mg/m2 /day) on days 2 to 6, every 28 days. RESULTS: Forty patients, aged 4 to 25 years, were enrolled. Talazoparib was increased to 600 µg/m2 /dose b.i.d. on day 1, and q.d. thereafter, with 20 mg/m2 /day of TMZ, without DLTs. TMZ was subsequently increased, during which dose-limiting neutropenia and thrombocytopenia occurred in two of three subjects at 55 mg/m2 /day, two of six subjects at 40 mg/m2 /day, and one of six subjects at 30 mg/m2 /day. During dose-finding, two of five EWS and four of 25 non-EWS subjects experienced prolonged stable disease (SD), and one subject with malignant glioma experienced a partial response. In phase 2, 0 of 10 EWS subjects experienced an objective response; two experienced prolonged SD. CONCLUSIONS: Talazoparib and low-dose TMZ are tolerated in children with recurrent/refractory solid tumors. Reversible neutropenia and thrombocytopenia were dose limiting. The RP2D is talazoparib 600 µg/m2 b.i.d. on day 1 followed by 600 µg/m2 q.d. on days 2 to 6 (daily maximum 1000 µg) in combination with temozolomide 30 mg/m2 /day on days 2 to 6. Antitumor activity was not observed in EWS, and limited antitumor activity was observed in central nervous system tumors.

A Phase II Study of Alisertib in Children with Recurrent/Refractory Solid Tumors or Leukemia: Children's Oncology Group Phase I and Pilot Consortium (ADVL0921).

PURPOSE: Aurora A kinase (AAK) plays an integral role in mitotic entry, DNA damage checkpoint recovery, and centrosome and spindle maturation. Alisertib (MLN8237) is a potent and selective AAK inhibitor. In pediatric preclinical models, antitumor activity was observed in neuroblastoma, acute lymphoblastic leukemia, and sarcoma xenografts. We conducted a phase 2 trial of alisertib in pediatric patients with refractory or recurrent solid tumors or acute leukemias (NCT01154816). PATIENTS AND METHODS: Alisertib (80 mg/m2/dose) was administered orally, daily for 7 days every 21 days. Pharmacogenomic (PG) evaluation for polymorphisms in the AURK gene and drug metabolizing enzymes (UGT1A1*28), and plasma pharmacokinetic studies (PK) were performed. Using a 2-stage design, patients were enrolled to 12 disease strata (10 solid tumor and 2 acute leukemia). Response was assessed after cycle 1, then every other cycle. RESULTS: A total of 139 children and adolescents (median age, 10 years) were enrolled, 137 were evaluable for response. Five objective responses were observed (2 complete responses and 3 partial responses). The most frequent toxicity was myelosuppression. The median alisertib trough concentration on day 4 was 1.3 µmol/L, exceeding the 1 µmol/L target trough concentration in 67% of patients. No correlations between PG or PK and toxicity were observed. CONCLUSIONS: Despite alisertib activity in pediatric xenograft models and cogent pharmacokinetic-pharmacodynamic relationships in preclinical models and adults, the objective response rate in children and adolescents receiving single-agent alisertib was less than 5%.

Current Activities of the Coalition of Cancer Cooperative Groups.

The Coalition of Cancer Cooperative Groups is an organization representing the interests of patients and researchers who conduct research through the National Cancer Institute-supported National Clinical Trials Network (NCTN). The NCTN provides a crucial mechanism for executing practice-changing cancer clinical research to achieve both cancer control and development of new therapeutic agents or modality approaches. Public funding, largely through the National Cancer Institute, ensures that the work of the NCTN achieves important research that would not otherwise be accomplished in the private sector. In fall 2017, the Coalition of Cancer Cooperative Groups convened a Scientific Leadership Council to review the current state of the network with regard to research capabilities and to develop a list of research questions to be prioritized by the network. This report presents the results of this meeting, detailing a roadmap for future work by the NCTN.

Brentuximab vedotin with gemcitabine for paediatric and young adult patients with relapsed or refractory Hodgkin's lymphoma (AHOD1221): a Children's Oncology Group, multicentre single-arm, phase 1-2 trial.

BACKGROUND: Patients with primary refractory Hodgkin's lymphoma or early relapse have a poor prognosis. Although many salvage regimens have been developed, there is no standard of care. Brentuximab vedotin and gemcitabine have been shown to be active in patients with relapsed or refractory Hodgkin's lymphoma when used as monotherapy, and each has been successfully used in combination with other agents. Preclinical data suggest that brentuximab vedotin can sensitise lymphoma cells to gemcitabine, supporting the use of the combination. We aimed to define the safety and efficacy of brentuximab vedotin with gemcitabine in children and young adults with primary refractory Hodgkin's lymphoma or early relapse. METHODS: In this Children's Oncology Group, multicentre, single-arm, phase 1-2 trial, we recruited patients with Hodgkin's lymphoma from hospitals across the USA and Canada. Eligible patients were aged younger than 30 years, had no previous brentuximab vedotin exposure, and had primary refractory disease or relapse of less than 1 year from completion of initial treatment. Each 21-day cycle consisted of 1000 mg/m2 intravenous gemcitabine on days 1 and 8 and intravenous brentuximab vedotin on day 1 at 1·4 mg/kg or 1·8 mg/kg. The primary objectives were to establish the recommended phase 2 dose of brentuximab vedotin in this combination, the safety of the combination, and the proportion of patients who achieved a complete response among those treated at the recommended phase 2 level, within four cycles of treatment. This trial is registered with ClinicalTrials.gov, number NCT01780662. FINDINGS: Between Feb 5, 2013, and Aug 19, 2016, 46 patients were enrolled, including one who was found to be ineligible, in the two phases of the study. The recommended phase 2 dose of brentuximab vedotin was 1·8 mg/kg in combination with gemcitabine 1000 mg/m2. 24 (57%) of 42 evaluable patients (95% CI 41-72) given this dose level had a complete response within the first four cycles of treatment. Four (31%) of 13 patients with a partial response or stable disease had all target lesions with Deauville scores of 3 or less after cycle 4. By modern response criteria, these were also complete responses (total number with complete response 28 [67%] of 42 [95% CI 51-80]). The most common grade 3-4 adverse events in all 42 participants treated at the recommended phase 2 dose were neutropenia (15 [36%]), rash (15 [36%]), transaminitis (9 [21%]), and pruritus (4 [10%]). There were no treatment-related deaths. INTERPRETATION: Brentuximab vedotin with gemcitabine is a safe combination treatment with a tolerable toxicity profile for patients with primary refractory Hodgkin's lymphoma or high-risk relapse. The preliminary activity of this combination shown in this trial warrants further investigation in randomised controlled trials. FUNDING: National Institutes of Health and the St. Baldrick's Foundation.

A phase 1 study of eribulin mesylate (E7389), a novel microtubule-targeting chemotherapeutic agent, in children with refractory or recurrent solid tumors: A Children's Oncology Group Phase 1 Consortium study (ADVL1314).

BACKGROUND: Eribulin mesylate is a novel anticancer agent that inhibits microtubule growth, without effects on shortening, and promotes nonproductive tubulin aggregate formation. We performed a phase 1 trial to determine the dose-limiting toxicities (DLTs), maximum tolerated or recommended phase 2 dose (MTD/RP2D), and pharmacokinetics (PK) of eribulin in children with refractory or recurrent solid (excluding central nervous system) tumors. METHODS: Eribulin was administered intravenously on days 1 and 8 in 21-day cycles. Three dose levels (1.1, 1.4, and 1.8 mg/m2 /dose) were evaluated using the rolling six design with additional patients enrolled into a PK expansion cohort at the MTD. PK samples were obtained following the day 1, cycle 1 dose. RESULTS: Twenty-three patients, ages 3-17 (median 14) years were enrolled; 20 were evaluable for toxicity. DLTs occurred in 0/6 and 1/6 subjects at the 1.1 and 1.4 mg/m2 /dose, respectively. One subject at the 1.4 mg/m2 /dose had grade 4 neutropenia and grade 3 fatigue. At the 1.8 mg/m2 /dose, 2/5 subjects experienced dose-limiting (grade 4) neutropenia. Grade 3/4 non-DLTs included lymphopenia and hypokalemia, while low-grade toxicities included anorexia and nausea. No episodes of grade > 2 corrected QT interval prolongation or peripheral neuropathy were reported. Eribulin pharmacokinetic parameters were highly variable; the median elimination half-life was 39.6 (range 24.2-96.4) hr. A partial response was observed in one patient (Ewing sarcoma). CONCLUSIONS: Eribulin was well tolerated in children with refractory or recurrent solid tumors with neutropenia identified as the primary DLT. The RP2D of eribulin is 1.4 mg/m2 /dose on days 1 and 8 of a 21-day cycle.

A phase 1 study of cabozantinib in children and adolescents with recurrent or refractory solid tumors, including CNS tumors: Trial ADVL1211, a report from the Children's Oncology Group.

BACKGROUND: We conducted a phase 1 trial to determine the maximum tolerated dose (MTD), toxicity profile, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary activity of cabozantinib in children with refractory or relapsed solid tumors. METHODS: Patients received cabozantinib tablets on a continuous dosing schedule in a rolling-six escalating phase 1 trial design. PK and PD studies were performed. RESULTS: Forty-one patients, median (range) age 13 (4-18) years, received cabozantinib to achieve a weekly cumulative dose equivalent to 30 (n = 6), 40 (n = 23). or 55 (n = 12) mg/m2 /day. At 40 mg/m2 /d, dose-limiting toxicities (DLTs) were palmar-plantar erythrodysesthesia syndrome, mucositis, and elevated alanine aminotransferase, lipase, and bilirubin. At 55 mg/m2 /d, hypertension, reversible posterior leukoencephalopathy syndrome, headache, fatigue, and proteinuria were DLTs. Frequent non-DLTs included diarrhea, hypothyroidism, fatigue, nausea, vomiting, elevated hepatic transaminases, and proteinuria. In subsequent cycles, DLTs occurred at all dose levels. Across all dose levels, the steady-state exposure and peak cabozantinib concentrations were similar. Four patients experienced a confirmed partial response: medullary thyroid cancer (MTC; n = 2), Wilms tumor, and clear cell sarcoma. Stable disease (>6 cycles) was seen in seven patients (MTC [n = 2], Ewing sarcoma, synovial sarcoma, alveolar soft part sarcoma, paraganglioma, and ependymoma). CONCLUSIONS: A protocol-defined MTD was not reached; DLTs and dose reductions for toxicity occurred in the first and subsequent cycles at all dose levels. Based on the toxicity profile, pharmacokinetics, and responses, the recommended dose of cabozantinib in pediatric patients with refractory solid tumors is 40 mg/m2 /day. A phase 2 study of cabozantinib is being conducted.

Outcome of pediatric patients with acute lymphoblastic leukemia/lymphoblastic lymphoma with hypersensitivity to pegaspargase treated with PEGylated Erwinia asparaginase, pegcrisantaspase: A report from the Children's Oncology Group.

BACKGROUND: Erwinia asparaginase is a Food and Drug Administration approved agent for the treatment of acute lymphoblastic leukemia (ALL) for patients who develop hypersensitivity to Escherichia coli derived asparaginases. Erwinia asparaginase is efficacious, but has a short half-life, requiring six doses to replace one dose of the most commonly used first-line asparaginase, pegaspargase, a polyethylene glycol (PEG) conjugated E. coli asparaginase. Pegcristantaspase, a recombinant PEGylated Erwinia asparaginase with improved pharmacokinetics, was developed for patients with hypersensitivity to pegaspargase. Here, we report a series of patients treated on a pediatric phase 2 trial of pegcrisantaspase. PROCEDURE: Pediatric patients with ALL or lymphoblastic lymphoma and hypersensitivity to pegaspargase enrolled on Children's Oncology Group trial AALL1421 (Jazz 13-011) and received intravenous pegcrisantaspase. Serum asparaginase activity (SAA) was monitored before and after dosing; immunogenicity assays were performed for antiasparaginase and anti-PEG antibodies and complement activation was evaluated. RESULTS: Three of the four treated patients experienced hypersensitivity to pegcrisantaspase manifested as clinical hypersensitivity reactions or rapid clearance of SAA. Immunogenicity assays demonstrated the presence of anti-PEG immunoglobulin G antibodies in all three hypersensitive patients, indicating a PEG-mediated immune response. CONCLUSIONS: This small series of patients, nonetheless, provides data, suggesting preexisting immunogenicity against the PEG moiety of pegaspargase and poses the question as to whether PEGylation may be an effective strategy to optimize Erwinia asparaginase administration. Further study of larger cohorts is needed to determine the incidence of preexisting antibodies against PEG-mediated hypersensitivity to pegaspargase.

A pediatric brain tumor consortium phase II trial of capecitabine rapidly disintegrating tablets with concomitant radiation therapy in children with newly diagnosed diffuse intrinsic pontine gliomas.

BACKGROUND: We conducted a phase II study of oral capecitabine rapidly disintegrating tablets given concurrently with radiation therapy (RT) to assess progression-free survival (PFS) in children with newly diagnosed diffuse intrinsic pontine gliomas (DIPG). PATIENTS AND METHODS: Children 3-17 years with newly diagnosed DIPG were eligible. Capecitabine, 650 mg/m2 /dose BID (maximum tolerated dose [MTD] in children with concurrent radiation), was administered for 9 weeks starting the first day of RT. Following a 2-week break, three courses of capecitabine, 1,250 mg/m2 /dose BID for 14 days followed by a 7-day rest, were administered. As prospectively designed, 10 evaluable patients treated at the MTD on the phase I trial were included in the phase II analyses. The design was based on comparison of the PFS distribution to a contemporary historical control (n = 140) with 90% power to detect a 15% absolute improvement in the 1-year PFS with a type-1 error rate, α = 0.10. RESULTS: Forty-four patients were evaluable for the phase II objectives. Capecitabine and RT was well tolerated with low-grade palmar plantar erythrodyesthesia, increased alanine aminotransferase, cytopenias, and vomiting the most commonly reported toxicities. Findings were significant for earlier progression with 1-year PFS of 7.21% (SE = 3.47%) in the capecitabine-treated cohort versus 15.59% (SE = 3.05%) in the historical control (P = 0.007), but there was no difference for overall survival (OS) distributions (P = 0.30). Tumor enhancement at diagnosis was associated with shorter PFS and OS. Capecitabine was rapidly absorbed and converted to its metabolites. CONCLUSION: Capecitabine did not improve the outcome for children with newly diagnosed DIPG.

Targeting ALK With Crizotinib in Pediatric Anaplastic Large Cell Lymphoma and Inflammatory Myofibroblastic Tumor: A Children's Oncology Group Study.

Purpose Fusions involving the ALK gene are the predominant genetic lesion underlying pediatric anaplastic large cell lymphomas (ALCL) and inflammatory myofibroblastic tumors (IMTs). We assessed the activity of the ALK inhibitor crizotinib in patients who had no known curative treatment options at diagnosis or with relapsed/recurrent disease. Methods In this study, 26 patients with relapsed/refractory ALK-positive ALCL and 14 patients with metastatic or inoperable ALK-positive IMT received crizotinib orally twice daily. Study objectives were measurement of efficacy and safety. Correlative studies evaluated the serial detection of NPM-ALK fusion transcripts in patients with ALCL. Results The overall response rates for patients with ALCL treated at doses of 165 (ALCL165) and 280 (ALCL280) mg/m2 were 83% and 90%, respectively. The overall response rate for patients with IMT (treated at 100, 165, and 280 mg/m2/dose) was 86%. A complete response was observed in 83% (five of six) of ALCL165, 80% (16 of 20) of ALCL280, and 36% (five of 14) of patients with IMT. Partial response rates were 0% (none of six), 10% (two of 20), and 50% (seven of 14), respectively. The median duration of therapy was 2.79, 0.4, and 1.63 years, respectively, with 12 patients ceasing protocol therapy to proceed to transplantation. The most common drug-related adverse event was decrease in neutrophil count in 33% and 70% of the ALCL165 and ALCL280 groups, respectively, and in 43% of patients with IMT. Levels of NPM-ALK decreased during therapy in most patients with ALCL. Conclusion The robust and sustained clinical responses to crizotinib therapy in patients with relapsed ALCL and metastatic or unresectable IMT highlight the importance of the ALK pathway in these diseases.

Pediatric Phase I Trial and Pharmacokinetic Study of Trebananib in Relapsed Solid Tumors, Including Primary Tumors of the Central Nervous System ADVL1115: A Children's Oncology Group Phase I Consortium Report.

Purpose: Trebananib is a first-in-class antiangiogenic peptibody (peptide-Fc fusion protein) that inhibits Angiopoietin 1 and 2. A pediatric phase 1 trial was performed to define trebananib dose-limiting toxicities (DLT), recommended phase 2 dose (RP2D), and pharmacokinetics (PK).Experimental Design: Trebananib was administered by weekly infusion. Three dose levels (10, 15, or 30 mg/kg/dose) were evaluated using a rolling-six design. Part 2 evaluated a cohort of subjects with primary central nervous system (CNS) tumors. Pharmacokinetic sampling and analysis of peripheral blood biomarkers was performed during the first 4 weeks. Response was evaluated after 8 weeks. Correlative studies included angiogenic protein expression and DCE-MRI.Results: Thirty-seven subjects were enrolled (31 evaluable for toxicity) with median age 12 years (range, 2 to 21). Two of 19 evaluable non-CNS subjects developed DLT at the 30 mg/kg dose level, including venous thrombosis and pleural effusion. In the CNS cohort, 3/12 subjects developed DLT, including decreased platelet count, transient ischemic attack, and cerebral edema with headache and hydrocephalus. Other grade 3 or 4 toxicities included lymphopenia (n = 4), anemia, thrombocytopenia, neutropenia, vomiting, and hypertension (n = 1 each). Response included stable disease in 7 subjects, no partial or complete responses. Two subjects continued study treatment with prolonged stable disease for 18 cycles (neuroblastoma) and 26 cycles (anaplastic astrocytoma). Pharmacokinetics appeared linear over 3 dose levels. Correlative studies demonstrated increased PlGF and sVCAM-1, but no change in endoglin or perfusion by DCE-MRI.Conclusions: Trebananib was well tolerated in pediatric patients with recurrent or refractory solid or CNS tumors. RP2D is 30 mg/kg. Clin Cancer Res; 23(20); 6062-9. ©2017 AACR.