Allogeneic Hematopoietic Stem Cell Transplantation (alloHSCT) Following Blinatumomab-Induced Remission in Pediatric Patients with Relapsed/Refractory (r/r) B-Precursor Acute Lymphoblastic Leukemia (ALL): Preliminary Results from a Phase I/II Stud

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Ifosfamide and vinorelbine is an effective reinduction regimen in children with refractory/relapsed Hodgkin lymphoma, AHOD00P1: a children\u27s oncology group report

BACKGROUND: We assessed the safety and efficacy of ifosfamide and vinorelbine (IV) as a less toxic and effective reinduction regimen for pediatric patients with relapsed or refractory Hodgkin Lymphoma. PROCEDURE: This multi-center Children\u27s Oncology Group phase II pilot study enrolled patients 3,000 mg/m(2) intravenous infusion over 24 hr on Days 1-4 and vinorelbine 25 mg/m(2) /dose intravenous push on Days 1 and 5 of each 21 day cycle with cytokine support. The study endpoints included estimation of key toxicities (cardiac, hepatic, or renal toxicity or toxic death), the rate of successful peripheral stem cell harvesting, and response after two cycles of therapy. RESULTS: Sixty-six patients received a median of two cycles of IV. Sixty-four of 66 were heavily pretreated, 4 had refractory disease, 55% were male and 79% had nodular sclerosis HL. The primary toxicities were hematologic. Harvested peripheral stem cells were sufficient for autologous transplantation in 46 of 54 patients for whom stem cell collection was attempted. The overall response rate (72%; 95% CI 59-83%) permitted the majority of patients to undergo subsequent stem cell transplantation. CONCLUSIONS: IV is a safe and effective re-induction regimen for salvage of pediatric patients with relapsed or refractory Hodgkin Lymphoma with an excellent response rate and success of post chemotherapy stem cell harvest. It avoids the use of etoposide, an agent associated with secondary malignancy after stem cell transplantation

A phase 1 study of oral ridaforolimus in pediatric patients with advanced solid tumors

Purpose Ridaforolimus is an investigational, potent, selective mTOR inhibitor. This study was conducted to determine the recommended phase 2 dose (RP2D), maximum tolerated dose, safety, pharmacokinetics, and antitumor activity of oral ridaforolimus in children with advanced solid tumors. Experimental Design In this phase 1, multicenter, open-label study in children aged 6 to <18 years with advanced solid tumors, ridaforolimus was administered orally for 5 consecutive days/week in 28-day cycles until progression, unacceptable toxicity, or consent withdrawal. Dose started at 22 mg/m2 and increased to 28 mg/m2 and 33 mg/m2, followed by expansion at the RP2D. Results: Twenty patients were treated; 18 were evaluable for dose-limiting toxicities. One dose-limiting toxicity (grade 3 increased alanine aminotransferase) occurred in 1 patient at 33 mg/m2. Dose escalation concluded at 33 mg/m2; the maximum tolerated dose was not determined. The most common treatment-related adverse events (frequency ≥40%) were manageable grade 1–2 stomatitis, thrombocytopenia, hypertriglyceridemia, increased alanine aminotransferase, fatigue, hypercholesterolemia, anemia, and increased aspartate aminotransferase. Ridaforolimus exposure at 28 mg/m2 and 33 mg/m2 exceeded adult target levels. The RP2D for oral ridaforolimus in children was defined as 33 mg/m2. Four patients received at least 4 cycles; 2 with pineoblastoma and diffuse intrinsic pontine glioma had stable disease for 12 and 46 cycles, respectively. Conclusions: Ridaforolimus is orally bioavailable and well tolerated in children with advanced solid tumors. The RP2D (33 mg/m2, 5 days/week) exceeds the adult RP2D. The favorable toxicity and pharmacokinetic profiles may allow for combination therapy, a promising therapeutic option in pediatric malignancies

Allogeneic Transplant Following Brentuximab Vedotin in Patients with Relapsed or Refractory Hodgkin Lymphoma and Systemic Anaplastic Large Cell Lymphoma.

Brentuximab vedotin is an antibody drug conjugate that induces durable objective responses in patients with relapsed or refractory Hodgkin lymphoma and systemic anaplastic large cell lymphoma. Fifteen of 160 patients who participated in two pivotal phase 2 studies received a consolidative allogeneic stem cell transplant (allo-SCT) following brentuximab vedotin treatment. This case series describes their experience. The studies were approved by Institutional Review Boards prior to patient enrollment. Patients received 1.8 mg/kg brentuximab vedotin every 3 weeks for up to 16 cycles. The estimated 2-year progression-free survival (PFS) rate was 66%, and the median PFS has not yet been reached. Eleven of the 15 patients were alive and the estimated 2-year survival rate was 80%. The safety of brentuximab vedotin treatment in this series was consistent with the known safety profile in this setting. Brentuximab vedotin is a compelling option for reducing tumor burden to facilitate a consolidative allo-SCT

Pertussis Immunity and Response to Tetanus-Reduced Diphtheria-Reduced Pertussis Vaccine (Tdap) after Autologous Peripheral Blood Stem Cell Transplantation

Pertussis is a highly contagious respiratory infection characterized by prolonged cough and inspiratory whoop. Despite widespread vaccination of children aged < 7 years, its incidence is steadily increasing in adolescents and adults, because of the known decrease in immunity following childhood immunization. In an effort to reduce pertussis in adolescents and adults, 2 vaccines containing tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) (BOOSTRIX and Adacel) were licensed in 2005 for use in adolescents, 1 of which (Adacel) contains less pertussis toxoid (PT) for use in adults. This study assessed pertussis titers in 57 adult survivors of an autologous peripheral blood stem cell transplantation (PBSCT; median age, 37.5 years), 28 of whom were subsequently vaccinated with Tdap containing 2.5 μg of PT (Adacel). The median time to Tdap administration was 3 years posttransplantation. Before vaccination, 87% of the patients lacked pertussis immunity. Only 2 of the 28 patients developed a >2-fold response to PT following vaccination with Tdap. These data suggest that autologous transplantation recipients are highly susceptible to pertussis and that immunization with 2.5 μg of PT induces an inadequate response. Prospective trials evaluating BOOSTRIX, containing 8 μg/dose of PT (approved for adults in December 2008) are warranted in this vulnerable population undergoing transplantation

Genetic basis for iMCD-TAFRO

TAFRO syndrome, a clinical subtype of idiopathic multicentric Castleman disease (iMCD), consists of a constellation of symptoms/signs including thrombocytopenia, anasarca, fever, reticulin fibrosis/renal dysfunction, and organomegaly. The etiology of iMCD-TAFRO and the basis for cytokine hypersecretion commonly seen in iMCD-TAFRO patients has not been elucidated. Here, we identified a somatic MEK2 mutation and a germline RUNX1 mutation in two patients with iMCD-TAFRO, respectively. The MEK2 mutation, which has been identified previously in solid tumor and histiocytosis patients, caused hyperactivated MAP kinase signaling, conferred IL-3 hypersensitivity and sensitized the cells to various MEK inhibitors. The RUNX1 mutation abolished the transcriptional activity of wild-type RUNX1 and functioned as a dominant negative form of RUNX1, resulting in enhanced self-renewal activity in hematopoietic stem/progenitor cells. Interestingly, ERK was heavily activated in both patients, highlighting a potential role for activation of MAPK signaling in iMCD-TAFRO pathogenesis and a rationale for exploring inhibition of the MAPK pathway as a therapy for iMCD-TAFRO. Moreover, these data suggest that iMCD-TAFRO might share pathogenetic features with clonal inflammatory disorders bearing MEK and RUNX1 mutations such as histiocytoses and myeloid neoplasms

A phase 1 study of the CXCR4 antagonist plerixafor in combination with high-dose cytarabine and etoposide in children with relapsed or refractory acute leukemias or myelodysplastic syndrome: a pediatric oncology experimental therapeutics investigators\u27 consortium study (POE 10-03).

BACKGROUND: Plerixafor, a reversible CXCR4 antagonist, inhibits interactions between leukemic blasts and the bone marrow stromal microenvironment and may enhance chemosensitivity. A phase 1 trial of plerixafor in combination with intensive chemotherapy in children and young adults with relapsed or refractory acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), and myelodysplastic syndrome (MDS) was performed to determine a tolerable and biologically active dose. PROCEDURE: Plerixafor was administered daily for 5 days at four dose levels (6, 9, 12, and 15 mg/m RESULTS: Nineteen patients (13 with AML, 5 with ALL, 1 with MDS) were treated. The most common grade 3 or greater nonhematologic toxicities attributable to plerixafor were febrile neutropenia and hypokalemia. There were no dose-limiting toxicities (DLTs). Plerixafor exposure increased with increasing dose levels and clearance was similar on days 1 and 5. Eighteen patients were evaluable for response. Two patients achieved complete remission (CR) and one patient achieved CR with incomplete hematologic recovery (CRi): all three had AML. No responses were seen in patients with ALL or MDS. Plerixafor mobilized leukemic blasts into the peripheral blood in 14 of 16 evaluable patients (median 3.4-fold increase), and the degree of mobilization correlated with surface CXCR4 expression. CONCLUSIONS: Plerixafor, in combination with high-dose cytarabine and etoposide, was well tolerated in children and young adults with relapsed/refractory acute leukemias and MDS. While biologic responses were observed, clinical responses in this heavily pretreated cohort were modest