Efficacy and safety of azacitidine in pediatric patients with newly diagnosed advanced myelodysplastic syndromes before hematopoietic stem cell transplantation in the AZA-JMML-001 trial.

Here we report efficacy, pharmacokinetics, and safety data obtained in treatment-naive, pediatric patients with newly diagnosed advanced MDS receiving azacitidine in the AZA-JMML-001 study. The primary endpoint was response rate (proportion of patients with complete response [CR], partial response [PR], or marrow CR, sustained for ≥4 weeks). Of the 10 patients enrolled, one had an unconfirmed marrow CR and none had confirmed responses after three cycles; the study was therefore closed after stage 1. Azacitidine was well tolerated. The lack of efficacy of azacitidine in pediatric patients with newly diagnosed advanced MDS highlights the need for effective new treatments in these patients.

Mezigdomide plus Dexamethasone in Relapsed and Refractory Multiple Myeloma.

BACKGROUND: Despite recent progress, multiple myeloma remains incurable. Mezigdomide is a novel cereblon E3 ubiquitin ligase modulator with potent antiproliferative and tumoricidal activity in preclinical models of multiple myeloma, including those resistant to lenalidomide and pomalidomide. METHODS: In this phase 1-2 study, we administered oral mezigdomide in combination with dexamethasone to patients with relapsed and refractory myeloma. The primary objectives of phase 1 (dose-escalation cohort) were to assess safety and pharmacokinetics and to identify the dose and schedule for phase 2. In phase 2 (dose-expansion cohort), objectives included the assessment of the overall response (partial response or better), safety, and efficacy of mezigdomide plus dexamethasone at the dose and schedule determined in phase 1. RESULTS: In phase 1, a total of 77 patients were enrolled in the study. The most common dose-limiting toxic effects were neutropenia and febrile neutropenia. On the basis of the phase 1 findings, investigators determined the recommended phase 2 dose of mezigdomide to be 1.0 mg, given once daily in combination with dexamethasone for 21 days, followed by 7 days off, in each 28-day cycle. In phase 2, a total of 101 patients received the dose identified in phase 1 in the same schedule. All patients in the dose-expansion cohort had triple-class-refractory multiple myeloma, 30 patients (30%) had received previous anti-B-cell maturation antigen (anti-BCMA) therapy, and 40 (40%) had plasmacytomas. The most common adverse events, almost all of which proved to be reversible, included neutropenia (in 77% of the patients) and infection (in 65%; grade 3, 29%; grade 4, 6%). No unexpected toxic effects were encountered. An overall response occurred in 41% of the patients (95% confidence interval [CI], 31 to 51), the median duration of response was 7.6 months (95% CI, 5.4 to 9.5; data not mature), and the median progression-free survival was 4.4 months (95% CI, 3.0 to 5.5), with a median follow-up of 7.5 months (range, 0.5 to 21.9). CONCLUSIONS: The all-oral combination of mezigdomide plus dexamethasone showed promising efficacy in patients with heavily pretreated multiple myeloma, with treatment-related adverse events consisting mainly of myelotoxic effects. (Funded by Celgene, a Bristol-Myers Squibb Company; CC-92480-MM-001 ClinicalTrials.gov number, NCT03374085; EudraCT number, 2017-001236-19.).

Response to upfront azacitidine in juvenile myelomonocytic leukemia in the AZA-JMML-001 trial.

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative therapy for most children with juvenile myelomonocytic leukemia (JMML). Novel therapies controlling the disorder prior to HSCT are needed. We conducted a phase 2, multicenter, open-label study to evaluate the safety and antileukemic activity of azacitidine monotherapy prior to HSCT in newly diagnosed JMML patients. Eighteen patients enrolled from September 2015 to November 2017 were treated with azacitidine (75 mg/m2) administered IV once daily on days 1 to 7 of a 28-day cycle. The primary end point was the number of patients with clinical complete remission (cCR) or clinical partial remission (cPR) after 3 cycles of therapy. Pharmacokinetics, genome-wide DNA-methylation levels, and variant allele frequencies of leukemia-specific index mutations were also analyzed. Sixteen patients completed 3 cycles and 5 patients completed 6 cycles. After 3 cycles, 11 patients (61%) were in cPR and 7 (39%) had progressive disease. Six of 16 patients (38%) who needed platelet transfusions were transfusion-free after 3 cycles. All 7 patients with intermediate- or low-methylation signatures in genome-wide DNA-methylation studies achieved cPR. Seventeen patients received HSCT; 14 (82%) were leukemia-free at a median follow-up of 23.8 months (range, 7.0-39.3 months) after HSCT. Azacitidine was well tolerated and plasma concentration--time profiles were similar to observed profiles in adults. In conclusion, azacitidine monotherapy is a suitable option for children with newly diagnosed JMML. Although long-term safety and efficacy remain to be fully elucidated in this population, these data demonstrate that azacitidine provides valuable clinical benefit to JMML patients prior to HSCT. This trial was registered at www.clinicaltrials.gov as #NCT02447666.

Phase 2 Study of Pomalidomide (CC-4047) Monotherapy for Children and Young Adults With Recurrent or Progressive Primary Brain Tumors.

INTRODUCTION: Treatment of recurrent primary pediatric brain tumors remains a major challenge, with most children succumbing to their disease. We conducted a prospective phase 2 study investigating the safety and efficacy of pomalidomide (POM) in children and young adults with recurrent and progressive primary brain tumors. METHODS: Patients with recurrent and progressive high-grade glioma (HGG), diffuse intrinsic pontine glioma (DIPG), ependymoma, or medulloblastoma received POM 2.6 mg/m2/day (the recommended phase 2 dose [RP2D]) on days 1-21 of a 28-day cycle. A Simon's Optimal 2-stage design was used to determine efficacy. Primary endpoints included objective response (OR) and long-term stable disease (LTSD) rates. Secondary endpoints included duration of response, progression-free survival (PFS), overall survival (OS), and safety. RESULTS: 46 patients were evaluable for response (HGG, n = 19; DIPG, ependymoma, and medulloblastoma, n = 9 each). Two patients with HGG achieved OR or LTSD (10.5% [95% CI, 1.3%-33.1%]; 1 partial response and 1 LTSD) and 1 patient with ependymoma had LTSD (11.1% [95% CI, 0.3%-48.2%]). There were no ORs or LTSD in the DIPG or medulloblastoma cohorts. The median PFS for patients with HGG, DIPG, ependymoma, and medulloblastoma was 7.86, 11.29, 8.43, and 8.43 weeks, respectively. Median OS was 5.06, 3.78, 12.02, and 11.60 months, respectively. Neutropenia was the most common grade 3/4 adverse event. CONCLUSIONS: Treatment with POM monotherapy did not meet the primary measure of success in any cohort. Future studies are needed to evaluate if POM would show efficacy in tumors with specific molecular signatures or in combination with other anticancer agents. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT03257631; EudraCT, identifier 2016-002903-25.

Results of a phase 2, multicenter, single-arm, open-label study of lenalidomide in pediatric patients with relapsed or refractory acute myeloid leukemia.

BACKGROUND: Outcomes after relapse remain poor in pediatric patients with acute myeloid leukemia (AML), and new therapeutic approaches are needed. Lenalidomide has demonstrated activity in adults with lower risk myelodysplastic syndromes and older adults with relapsed or refractory (R/R) AML. METHODS: In this phase 2 study (NCT02538965), pediatric patients with R/R AML who received two or more prior therapies were treated with lenalidomide (starting dose 2 mg/kg/day on days 1-21 of each 28-day cycle) for a maximum of 12 cycles. The primary endpoint was rate of complete response (CR) and CR with incomplete blood count recovery (CRi) within the first four cycles. RESULTS: Seventeen patients enrolled and received one or more dose of lenalidomide. Median age was 12 years (range 5-18 years), median white blood cell count was 3.7 × 109 /L, and median peripheral blood blast count was 1.0 × 109 /L. One patient (5.9%) with a complex karyotype including del(5q) achieved CRi after two cycles of lenalidomide. This responder proceeded to a second hematopoietic stem cell transplantation and has remained without evidence of disease for 3 years. All patients experienced one or more of grades 3-4 treatment-emergent adverse event (TEAE). The most common grades 3-4 TEAEs were thrombocytopenia (58.8%), febrile neutropenia (47.1%), anemia (41.2%), and hypokalemia (41.2%). CONCLUSIONS: In this population of pediatric patients with R/R AML, safety data were consistent with the known safety profile of lenalidomide. As only one patient responded, further evaluation of lenalidomide at the dose and schedule studied is not warranted in pediatric AML, with the possible exception of patients with del(5q).

Phase 1 safety, pharmacokinetic and pharmacodynamic study of the cyclin-dependent kinase inhibitor dinaciclib administered every three weeks in patients with advanced malignancies.

BACKGROUND: Dinaciclib is a potent inhibitor of cell cycle and transcriptional cyclin-dependent kinases. This Phase 1 study evaluated the safety, tolerability and pharmacokinetics of various dosing schedules of dinaciclib in advanced solid tumour patients and assessed pharmacodynamic and preliminary anti-tumour activity. METHODS: In part 1, patients were enrolled in escalating cohorts of 2-h infusions administered once every 3 weeks, utilising an accelerated titration design until a recommended phase 2 dose (RP2D) was defined. In part 2, 8- and 24-h infusions were evaluated. Pharmacokinetic parameters were determined for all schedules. Pharmacodynamic effects were assessed with an ex vivo stimulated lymphocyte proliferation assay performed in whole blood.Effects of dinaciclib on retinoblastoma (Rb) phosphorylation and other CDK targets were evaluated in skin and tumour biopsies. In addition to tumour size, metabolic response was evaluated by 18F-fluorodeoxyglucose-positron emission tomography. RESULTS: Sixty-one patients were enrolled to parts 1 and 2. The RP2Ds were 50, 7.4 and 10.4 mg m-2 as 2- 8- and 24-hour infusions, respectively. Dose-limiting toxicities included pancytopenia, neutropenic fever, elevated transaminases, hyperuricemia and hypotension. Pharmacokinetics demonstrated rapid distribution and a short plasma half-life. Dinaciclib suppressed proliferation of stimulated lymphocytes. In skin and tumour biopsies, dinaciclib reduced Rb phosphorylation at CDK2 phospho-sites and modulated expression of cyclin D1 and p53, suggestive of CDK9 inhibition. Although there were no RECIST responses, eight patients had prolonged stable disease and received between 6 and 30 cycles. Early metabolic responses occurred. CONCLUSIONS: Dinaciclib is tolerable at doses demonstrating target engagement in surrogate and tumour tissue.

Clinical and laboratory studies of the novel cyclin-dependent kinase inhibitor dinaciclib (SCH 727965) in acute leukemias.

PURPOSE: Dinaciclib inhibits cyclin-dependent kinases 1, 2, 5, and 9 with a better therapeutic index than flavopiridol in preclinical studies. This study assessed the activity of dinaciclib in acute leukemia both in the clinic and in vitro. METHODS: Adults with relapsed/refractory acute myeloid leukemia (n = 14) and acute lymphoid leukemia (n = 6) were treated with dinaciclib 50 mg/m(2) given as a 2-h infusion every 21 days. RESULTS: Most patients had dramatic but transient reduction in circulating blasts; however, no remissions were achieved on this schedule. The most common toxicities were gastrointestinal, fatigue, transaminitis, and clinical and laboratory manifestations of tumor lysis syndrome, including one patient who died of acute renal failure. Dinaciclib pharmacokinetics showed rapid (2 h) achievement of maximum concentration and a short elimination/distribution phase. Pharmacodynamic studies demonstrated in vivo inhibition of Mcl-1 expression and induction of PARP cleavage in patients' peripheral blood mononuclear cells 4 h after dinaciclib infusion, but the effects were lost by 24 h and did not correlate with clinical outcome. Correlative in vitro studies showed that prolonged exposures to dinaciclib, at clinically attainable concentrations, result in improved leukemia cell kill. CONCLUSIONS: While dinaciclib given as a 2-h bolus did not exhibit durable clinical activity, pharmacokinetic and pharmacodynamic data support the exploration of prolonged infusion schedules in future trials in patients with acute leukemias.

Effect of aprepitant on the pharmacokinetics of the cyclin-dependent kinase inhibitor dinaciclib in patients with advanced malignancies.

PURPOSE: Dinaciclib, a selective inhibitor of cyclin-dependent kinase (CDK) 1, CDK2, CDK5, and CDK9, is metabolized via CYP3A4. Aprepitant, a neurokinin-1 receptor antagonist for the prevention of chemotherapy-induced nausea and vomiting, is an inhibitor and inducer of CYP3A4. We conducted a randomized, crossover study to investigate the effects of single oral doses of aprepitant when coadministered with dinaciclib. METHODS: As part of a phase 1 dose-escalation trial, subjects with advanced malignancies were randomized into a 2-period, multi-cycle, crossover study to investigate the effect of single doses of oral aprepitant on the pharmacokinetics of 29.6 mg/m(2) dinaciclib administered by 2-h intravenous infusion. During cycle 1 and cycle 2, subjects received dinaciclib with aprepitant in one cycle and dinaciclib without aprepitant in the other cycle; aprepitant was administered at a dose of 125 mg orally on day 1 and 80 mg orally on days 2 and 3, along with standard dosing regimens of ondansetron and dexamethasone. RESULTS: Twelve patients completed the study; T (max) occurred approximately 2 h after the initiation of the infusion. The percent geometric mean ratio (dinaciclib + aprepitant vs. dinaciclib alone) was 106 % (90 % confidence interval [CI] 89-126 %) and 111 % (90 % CI 93-132 %) for dinaciclib C(max) and AUC([I]), respectively. The half-life and clearance of dinaciclib were similar, with or without aprepitant. CONCLUSIONS: Coadministration of dinaciclib with aprepitant resulted in no clinically significant effect on the pharmacokinetics and did not alter the safety profile of dinaciclib in patients with advanced malignancies.

Developmental delay timely identification and assessment.

This paper outlines the prevalence of developmental delay in children and discusses the recent literature regarding the benefits of early identification and evidence based strategies for developmental surveillance and screening. We describe a systematic approach to the child with developmental delay and the optimal methodology for arriving at the etiologic basis for the delay. A review of the most upto date and relevant literature was completed using Pub Med, online databases, and texts. The medical evaluation with specific emphasis on the most recent recommendations for genetic, laboratory and imaging studies is described. The American Academy of Pediatrics algorithm for developmental surveillance and screening is discussed with consideration for the importance of culturally relevant screening tools across populations. In addition, specific screening tools are briefly discussed that may prove beneficial to the primary care provider as he/she implements routine surveillance and screening.