A phase 1 study of mebendazole with bevacizumab and irinotecan in high-grade gliomas.

BACKGROUND: High-grade gliomas (HGG) have a dismal prognosis despite multimodal therapy. Mebendazole is an anti-helminthic benzimidazole that has demonstrated efficacy in numerous in vitro cancer models, and is able to cross the blood-brain barrier. We conducted a phase 1 trial (NCT01837862) to evaluate the safety of mebendazole in combination with bevacizumab and irinotecan in children and young adults with HGG. OBJECTIVE: To determine the maximally tolerated dose of mebendazole when given in combination with bevacizumab and irinotecan in children with HGG; to describe the progression-free survival (PFS) and overall survival (OS) for this group. DESIGN/METHOD: Patients between 1 and 21 years of age with HGG were enrolled in a 3 + 3 design to escalating doses of mebendazole in combination with bevacizumab (10 mg/kg/dose) and irinotecan (150 mg/m2 /dose). Subjects were eligible upfront after completion of radiation or at the time of progression. Mebendazole was taken orally twice per day continuously, and bevacizumab and irinotecan were given intravenously on Days 1 and 15 of 28-day cycles. RESULTS: Between 2015 and 2020, 10 subjects were enrolled at mebendazole doses of 50 mg/kg/day (n = 3), 100 mg/kg/day (n = 4), and 200 mg/kg/day (n = 3). One subject assigned to 100 mg/kg/day was not evaluable. Seven subjects had a diagnosis of diffuse midline glioma, one subject had anaplastic astrocytoma, and one subject had a spinal HGG. All subjects received radiation. There were no dose-limiting toxicities. The most frequent G3/4 adverse events were neutropenia (n = 3) and lymphopenia (n = 4). The overall response rate was 33%, with two subjects achieving a partial response and one subject achieving a complete response sustained for 10 months. The mean PFS and OS from the start of study treatment were 4.7 and 11.4 months, respectively. CONCLUSION: Mebendazole was safe and well tolerated when administered with bevacizumab and irinotecan at doses up to 200 mg/kg/day. Further studies are needed to determine the efficacy of this treatment.

Bosutinib in Resistant and Intolerant Pediatric Patients With Chronic Phase Chronic Myeloid Leukemia: Results From the Phase I Part of Study ITCC054/COG AAML1921.

PURPOSE: Bosutinib is approved for adults with chronic myeloid leukemia (CML): 400 mg once daily in newly diagnosed (ND); 500 mg once daily in resistant/intolerant (R/I) patients. Bosutinib has a different tolerability profile than other tyrosine kinase inhibitors (TKIs) and potentially less impact on growth (preclinical data). The primary objective of this first-in-child trial was to determine the recommended phase II dose (RP2D) for pediatric R/I and ND patients. PATIENTS AND METHODS: In the phase I part of this international, open-label trial (ClinicalTrials.gov identifier: NCT04258943), children age 1-18 years with R/I (per European LeukemiaNet 2013) Ph+ CML were enrolled using a 6 + 4 design, testing 300, 350, and 400 mg/m2 once daily with food. The RP2D was the dose resulting in 0/6 or 1/10 dose-limiting toxicities (DLTs) during the first cycle and achieving adult target AUC levels for the respective indication. As ND participants were only enrolled in phase II, the ND RP2D was selected based on data from R/I patients. RESULTS: Thirty patients were enrolled; 27 were evaluable for DLT: six at 300 mg/m2, 11 at 350 mg/m2 (one DLT), and 10 at 400 mg/m2 (one DLT). The mean AUCs at 300 mg/m2, 350 mg/m2, and 400 mg/m2 were 2.20 µg h/mL, 2.52 µg h/mL, and 2.66 µg h/mL, respectively. The most common adverse event was diarrhea (93%; ≥grade 3: 11%). Seven patients stopped because of intolerance and eight because of insufficient response. Complete cytogenetic and major molecular response to bosutinib appeared comparable with other published phase I/II trials with second-generation TKIs in children. CONCLUSION: Bosutinib was safe and effective. The pediatric RP2D was 400 mg/m2 once daily (max 600 mg/d) with food in R/I patients and 300 mg/m2 once daily (max 500 mg/d) with food in ND patients, which achieved targeted exposures as per adult experience.

Treatment of High-Risk Neuroblastoma.

High-risk neuroblastoma is a highly aggressive solid tumor that most commonly presents in early childhood. Advances in treatment through decades of clinical trials and research have led to improved outcomes. This review provides an overview of the current state of treatment for high-risk neuroblastoma.

Upfront molecular targeted therapy for the treatment of BRAF-mutant pediatric high-grade glioma.

BACKGROUND: The prognosis for patients with pediatric high-grade glioma (pHGG) is poor despite aggressive multimodal therapy. Objective responses to targeted therapy with BRAF inhibitors have been reported in some patients with recurrent BRAF-mutant pHGG but are rarely sustained. METHODS: We performed a retrospective, multi-institutional review of patients with BRAF-mutant pHGG treated with off-label BRAF +/- MEK inhibitors as part of their initial therapy. RESULTS: Nineteen patients were identified, with a median age of 11.7 years (range, 2.3-21.4). Histologic diagnoses included HGG (n = 6), glioblastoma (n = 3), anaplastic ganglioglioma (n = 4), diffuse midline glioma (n = 3), high-grade neuroepithelial tumor (n = 1), anaplastic astrocytoma (n = 1), and anaplastic astroblastoma (n = 1). Recurrent concomitant oncogenic alterations included CDKN2A/B loss, H3 K27M, as well as mutations in ATRX, EGFR, and TERT. Eight patients received BRAF inhibitor monotherapy. Eleven patients received combination therapy with BRAF and MEK inhibitors. Most patients tolerated long-term treatment well with no grade 4-5 toxicities. Objective and durable imaging responses were seen in the majority of patients with measurable disease. At a median follow-up of 2.3 years (range, 0.3-6.5), three-year progression-free and overall survival for the cohort were 65% and 82%, respectively, and superior to a historical control cohort of BRAF-mutant pHGG patients treated with conventional therapies. CONCLUSIONS: Upfront targeted therapy for patients with BRAF-mutant pHGG is feasible and effective, with superior clinical outcomes compared to historical data. This promising treatment paradigm is currently being evaluated prospectively in the Children's Oncology Group ACNS1723 clinical trial.

Phase 1 trial of olaratumab monotherapy and in combination with chemotherapy in pediatric patients with relapsed/refractory solid and central nervous system tumors.

Olaratumab is a monoclonal antibody that specifically binds to platelet-derived growth factor receptor alpha (PDGFRα) and blocks receptor activation. We conducted a phase 1 trial to evaluate the safety of olaratumab and determine a recommended dose in combination with three different chemotherapy regimens in children. Patients <18 years with relapsed/refractory solid or central nervous system tumors were enrolled to two dose levels of olaratumab. Patients received olaratumab monotherapy at 15 mg/kg (Part A) or 20 mg/kg (Part B) on Days 1 and 8 of the first 21-day cycle, followed by olaratumab combined with standard fixed doses of chemotherapy with doxorubicin, vincristine/irinotecan, or high-dose ifosfamide by investigator choice for subsequent 21-day cycles. In Part C, patients received olaratumab 20 mg/kg plus assigned chemotherapy for all cycles. Parts A-C enrolled 68 patients across three chemotherapy treatment arms; olaratumab in combination with doxorubicin (N = 16), vincristine/irinotecan (N = 26), or ifosfamide (N = 26). Three dose-limiting toxicities (DLTs) occurred during olaratumab monotherapy (at 15 mg/kg, grade [G] 4 alanine aminotransferase [ALT]; at 20 mg/kg, G3 lung infection and G3 gamma-glutamyl transferase). One DLT occurred during vincristine/irinotecan with olaratumab 20 mg/kg therapy (G3 ALT). Treatment-emergent adverse events ≥G3 in >25% of patients included neutropenia, anemia, leukopenia, lymphopenia, and thrombocytopenia. Pharmacokinetic profiles of olaratumab with chemotherapy were within the projected range based on adult data. There was one complete response (rhabdomyosarcoma [Part B vincristine/irinotecan arm]) and three partial responses (two rhabdomyosarcoma [Part A doxorubicin arm and Part C doxorubicin arm]; one pineoblastoma [Part B vincristine/irinotecan arm]). Olaratumab was tolerable and safely administered in combination with chemotherapy regimens commonly used in children and adolescents.

Arterial stiffness in childhood cancer survivors.

BACKGROUND: Cardiovascular disease is prevalent among childhood cancer survivors (CCS). Arterial stiffness measured by pulse wave velocity (PWV) may be predictive of cardiovascular morbidity. Increased PWV has been seen in adults following chemotherapy. PURPOSE: To evaluate PWV in a cohort of CCS and healthy controls. PATIENTS AND METHODS: All participants were >6 years old. CCS were >12 months off-therapy and free of cardiac disease, diabetes, and kidney dysfunction. Height, weight, blood pressure (BP), medications, cancer diagnosis, age at diagnosis, time off therapy, chemotherapy, and radiation exposures were recorded. PWV was measured on all participants. RESULTS: Sixty-eight CCS (mean 17.3 ± 6 years, 52.9% male), and 51 controls (mean 18.4 ± 5.5 years, 37.3% male) were evaluated. Among CCS, 34% had lymphoma, 44% leukemia, and 22% solid tumors, and 49% were exposed to radiation. CCS were off therapy 7 ± 4.2 years. Both groups were statistically similar in age, BMI, and BP. CCS ≥ 18 years old had significantly higher PWV compared to controls ≥ 18 years old (6.37 ± 0.89 vs. 5.76 ± 0.88 m/sec, P = 0.012). The relationship persisted in a regression model adjusted for age, sex, and BMI z-score (ß = 0.52, 95%CI 0.051-0.979, P = 0.03). Seventy percent of CCS ≥ 18 had elevated PWV compared to established norms. Radiation therapy, anthracycline dose, and chemotherapy exposures were not predictive of increased PWV in CCS. CONCLUSIONS: CCS ≥ 18 demonstrated prematurely elevated PVW. Further studies are needed to determine the predictive value of PWV in this population and its utility as a screening modality.

Stem cell transplant for children with sickle cell anemia: parent and patient interest.

We describe adolescents' and parents' interest in hematopoietic stem cell transplant (HSCT) as a cure for sickle cell disease (SCD) and factors associated with increased interest. We administered a 40 question survey to assess the interest in HSCT in parents and adolescents with HBSS or HBSß(0) thalassemia. The survey tool assessed factors that may influence interest in HSCT including demographic data, disease severity, views on prognosis, and health-related quality of life (HRQOL). All participants were given a handout on the risks and benefits of an HSCT before completing the survey. One hundred twenty-nine parents and 59 adolescents completed the survey. Forty-five percent of parents (54 of 119) would likely have their child undergo HSCT, and 35% of adolescents (19 of 55) would likely undergo HSCT if it was recommended by their hematologist. Parents of adolescents, as well as adolescent patients with better HRQOL, were more interested in HSCT. Prior exchange transfusion was associated with increased interest in HSCT (62% [23 of 37] versus 38% [29 of 76]; P = .02). The majority of parents believe their child's SCD will get better (66%; [80 of 122]), will not likely prevent their child from achieving life goals (83%; [100 of 121]), and will not shorten their child's lifespan (86%; [102 of 119]). There is strong parent and adolescent interest in HSCT as a cure for SCD. It is concerning that few parents and adolescents believe SCD will negatively impact their prognosis. Education on the potential long-term sequelae of SCD is needed when considering the role for HSCT.