Phase II Trial of Dabrafenib Plus Trametinib in Relapsed/Refractory BRAF V600-Mutant Pediatric High-Grade Glioma

PURPOSE: BRAF V600 mutation is detected in 5%-10% of pediatric high-grade gliomas (pHGGs), and effective treatments are limited. In previous trials, dabrafenib as monotherapy or in combination with trametinib demonstrated activity in children and adults with relapsed/refractory BRAF V600-mutant HGG. METHODS: This phase II study evaluated dabrafenib plus trametinib in patients with relapsed/refractory BRAF V600-mutant pHGG. The primary objective was overall response rate (ORR) by independent review by Response Assessment in Neuro-Oncology criteria. Secondary objectives included ORR by investigator determination, duration of response (DOR), progression-free survival, overall survival (OS), and safety. RESULTS: A total of 41 pediatric patients with previously treated BRAF V600-mutant HGG were enrolled. At primary analysis, median follow-up was 25.1 months, and 51% of patients remained on treatment. Sixteen of 20 discontinuations were due to progressive disease in this relapsed/refractory pHGG population. Independently assessed ORR was 56% (95% CI, 40 to 72). Median DOR was 22.2 months (95% CI, 7.6 months to not reached [NR]). Fourteen deaths were reported. Median OS was 32.8 months (95% CI, 19.2 months to NR). The most common all-cause adverse events (AEs) were pyrexia (51%), headache (34%), and dry skin (32%). Two patients (5%) had AEs (both rash) leading to discontinuation. CONCLUSION: In relapsed/refractory BRAF V600-mutant pHGG, dabrafenib plus trametinib improved ORR versus previous trials of chemotherapy in molecularly unselected patients with pHGG and was associated with durable responses and encouraging survival. These findings suggest that dabrafenib plus trametinib is a promising targeted therapy option for children and adolescents with relapsed/refractory BRAF V600-mutant HGG

Randomized Phase III Trial Comparing Single-Agent Paclitaxel Poliglumex (CT-2103, PPX) with Single-Agent Gemcitabine or Vinorelbine for the Treatment of PS 2 Patients with Chemotherapy-Naïve Advanced Non-small Cell Lung Cancer

BACKGROUND: Patients with advanced non-small cell lung cancer (NSCLC) and impaired performance status (PS >or= 2) have limited life expectancies and decreased tolerance for drug-induced toxicities. Current treatment guidelines indicate that PS 2 patients benefit from systemic therapy. Further refinement of treatment in these patients requires reduction of treatment-associated toxicities while maintaining or improving efficacy. Paclitaxel poliglumex (PPX), a macromolecular polymer-drug conjugate of paclitaxel and poly-l-glutamic acid, may enhance the therapeutic index of paclitaxel. METHODS: Chemotherapy-naive PS 2 patients with advanced NSCLC randomly received single-agent PPX (175 mg/m) or a comparator (single-agent vinorelbine or gemcitabine). The primary end point of this study was overall survival. RESULTS: Overall survival was similar between treatment arms (hazard ratio [HR] = 0.95; log-rank p = 0.686). Median and 1-year survival were 7.3 months and 26%, respectively, for PPX versus 6.6 months and 26% for the control arm. There was a nonsignificant trend toward improved survival in women in the PPX arm compared with standard single agents (HR = 0.65; p = 0.069). The most frequent grade 3/4 adverse events in the treatment versus control arm were dyspnea (13% versus 17%, respectively) and fatigue (10% versus 9%). Grade 3/4 neutropenia and anemia were reduced in the PPX arm (2% versus 8% and 3% versus 9%, respectively). Neuropathy, a taxane-specific toxicity, was more common in the PPX arm; grade 3 neuropathy was limited to 3%. CONCLUSIONS: Single-agent PPX, dosed at 175 mg/m, is active and well tolerated in PS 2 patients with advanced NSCLC. Patients on PPX required fewer red blood cell transfusions, hematopoietic growth factors, opioid analgesics, and clinic visits than patients receiving gemcitabine or vinorelbine

Acute Myeloid Leukemia Randomized, phase IIb study of low-dose cytarabine and lintuzumab versus low-dose cytarabine and placebo in older adults with untreated acute myeloid leukemia

Improving outcomes in older adults with acute myeloid leukemia remains a formidable challenge. Lintuzumab (SGN-33; HuM195) is a humanized monoclonal antibody directed against CD33, which is expressed on the majority of myeloblasts in acute myeloid leukemia. The primary objective of this randomized, double-blinded, placebocontrolled trial was to determine whether addition of lintuzumab to low-dose cytarabine would increase overall survival in adults aged 60 years and over with untreated acute myeloid leukemia

Randomized, phase IIb study of low-dose cytarabine and lintuzumab versus low-dose cytarabine and placebo in older adults with untreated acute myeloid leukemia

Improving outcomes in older adults with acute myeloid leukemia remains a formidable challenge. Lintuzumab (SGN-33; HuM195) is a humanized monoclonal antibody directed against CD33, which is expressed on the majority of myeloblasts in acute myeloid leukemia. The primary objective of this randomized, double-blinded, placebo-controlled trial was to determine whether addition of lintuzumab to low-dose cytarabine would increase overall survival in adults aged 60 years and over with untreated acute myeloid leukemia. Randomization was stratified by age, previous hematologic disorder, and performance status. All patients received cytarabine (20 mg subcutaneously twice daily) on Days 1-10 of each 28-day cycle. Patients received lintuzumab (600 mg) or placebo intravenously once weekly in Cycle 1 and once every other week in Cycles 2-12. A total of 211 patients (107 lintuzumab, 104 placebo) were randomized. Median age was 70 years (range 60-90). Survival was not significantly prolonged with lintuzumab treatment (hazard ratio 0.96; 95% confidence interval (CI) 0.72-1.28; P=0.7585). Median survival was similar between treatment arms (4.7 months lintuzumab vs. 5.1 months placebo) and in the subgroup of patients with high-risk cytogenetics (4.5 months). Infusion-related reactions, predominantly Grades 1-2, occurred more commonly in the lintuzumab arm (51% vs. 7% placebo); no other clinically significant difference in safety was noted. These results confirm that lintuzumab in combination with low-dose cytarabine did not prolong survival and that low-dose cytarabine remains a valid comparator for trials of non-intensive therapies in older patients with acute myeloid leukemia, regardless of cytogenetic profile

Lintuzumab and Low-Dose Cytarabine Compared to Placebo and Low-Dose Cytarabine in Patients with Untreated Acute Myeloid Leukemia (AML) 60 Years and Older: Results of a Randomized, Double-Blinded Phase 2b Study

Abstract Abstract 3613 Background: Older adults with AML who decline intensive induction chemotherapy lack effective therapeutic options, as evidenced by a median overall survival (OS) of ∼5 months with low-dose cytarabine treatment (Burnett 2007). Leukemic blast cells express CD33 in most patients with AML. While antitumor activity has been previously demonstrated by CD33-directed agents, none of these are currently available. Lintuzumab (SGN-33) is a humanized antibody directed to CD33 that was studied in patients with myeloid malignancies and demonstrated tolerability with modest monotherapy activity. To determine if the addition of lintuzumab to low-dose cytarabine could prolong survival in older patients with untreated AML, a randomized, placebo-controlled, double-blinded phase 2b study was conducted (ClinicalTrials.gov #NCT00528333). Methods: The study was conducted at 72 international sites between November 2007 and August 2010. Patients were >60 years of age with centrally confirmed, previously untreated AML; the minimum blast percentage required was 20% with ≥50% CD33 expression. Maximum allowed WBC at baseline was 30,000/μL. All patients declined treatment with intensive induction chemotherapy. Cytarabine 20 mg was administered SC twice daily on Days 1–10 of each 28-day cycle (12 cycles maximum). Patients were randomized to additionally receive either lintuzumab 600 mg or placebo IV: in Cycle 1 on Days 1, 8, 15, and 22, and on Days 1 and 15 of subsequent cycles. Patients were stratified according to age, ECOG performance status (PS), and history of antecedent hematologic disorder (AHD). Cytogenetic risk was determined at baseline according to Fröling 2006. The primary endpoint of the study was OS, determined using an unstratified log rank test. Secondary endpoints included peripheral blood count recovery, transfusion requirements, infection rates, and quality of life. As patients choosing less-intensive therapy often incorporate quality of life into their treatment decision, follow-up bone marrow biopsies were not required in the study. Results: 211 patients were randomized in the study (107 lintuzumab arm, 104 placebo arm). The study arms appeared balanced; overall, the median patient age was 70 years (range 60–90), 53% were female, and baseline ECOG PS was 0/1 (55%) or 2 (45%). Baseline blast percentages were ≥30% in 74% of patients and 23% had a history of AHD. A median of 95% CD33 expression was documented at baseline in either bone marrow or peripheral blood. Median number of treatment cycles was 4 in the lintuzumab arm and 3 in the placebo arm. At the time of the analysis, 24 patients were alive and the maximum follow-up was 32 months. The estimated median OS for the lintuzumab + low-dose cytarabine arm was 4.7 months compared with 5.1 months for the placebo + low-dose cytarabine arm with a hazard ratio (lintuzumab to placebo) of 0.96, indicating that lintuzumab was not associated with a treatment effect (P value 0.76, 95% CI [0.72, 1.28]). Rates of infections or fevers of unknown origin requiring hospitalization or IV antibiotics did not differ between the study arms. Overall, 28% of patients were observed to have no peripheral blasts, ANC >1.0 x109/L, platelets >100 × 109/L, and no transfusions for at least 1 week. The median OS among all patients was 5.0 months, which was significantly impacted by cytogenetic risk (8.7 months for standard-risk compared with 4.5 months for high-risk; P value 0.0024). The incidence of adverse events (AEs) was comparable between the treatment groups, with the exception of infusion-related reactions which occurred more frequently in the lintuzumab arm. The most common ≥ Grade 3 non-hematologic AEs in the study were pneumonia (12%) and sepsis (8%). Conclusions: In this randomized, placebo-controlled, double-blinded phase 2b trial, the combination of lintuzumab and low-dose cytarabine did not improve OS compared with placebo and low-dose cytarabine. While lintuzumab was not effective, CD33 remains a compelling target for AML because it is widely expressed by malignant cells and appears to be absent from pluripotent hematopoietic stem cells. This was the largest study to date of patients treated with low-dose cytarabine; the median OS across both treatment arms was 5 months. A similar outcome was observed in the subgroup of patients with high-risk cytogenetics, confirming that low-dose cytarabine remains a valid comparator in trials of older patients with AML. Disclosures: Lancet: Seattle Genetics, Inc.: Research Funding. Off Label Use: Lintuzumab is an investigational monoclonal antibody directed against CD33. Sekeres:Celgene Corp.: Membership on an entity's Board of Directors or advisory committees; Celgene Corp.: Honoraria; Seattle Genetics, Inc.: Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees. Wood:Seattle Genetics, Inc.: Research Funding. Grove:Seattle Genetics, Inc.: Equity Ownership; Seattle Genetics, Inc.: Employment. Sandalic:Seattle Genetics, Inc.: Equity Ownership; Seattle Genetics, Inc.: Employment. Sievers:Seattle Genetics: Employment, Equity Ownership. Jurcic:Seattle Genetics, Inc.: Consultancy; Seattle Genetics, Inc.: Membership on an entity's Board of Directors or advisory committees; Seattle Genetics, Inc.: Research Funding

Randomized Phase III Trial Comparing Single-Agent Paclitaxel Poliglumex (CT-2103, PPX) with Single-Agent Gemcitabine or Vinorelbine for the Treatment of PS 2 Patients with Chemotherapy-Naïve Advanced Non-small Cell Lung Cancer

BackgroundPatients with advanced non-small cell lung cancer (NSCLC) and impaired performance status (PS ≥ 2) have limited life expectancies and decreased tolerance for drug-induced toxicities. Current treatment guidelines indicate that PS 2 patients benefit from systemic therapy. Further refinement of treatment in these patients requires reduction of treatment-associated toxicities while maintaining or improving efficacy. Paclitaxel poliglumex (PPX), a macromolecular polymer–drug conjugate of paclitaxel and poly-l-glutamic acid, may enhance the therapeutic index of paclitaxel.MethodsChemotherapy-naive PS 2 patients with advanced NSCLC randomly received single-agent PPX (175 mg/m2) or a comparator (single-agent vinorelbine or gemcitabine). The primary end point of this study was overall survival.ResultsOverall survival was similar between treatment arms (hazard ratio [HR] = 0.95; log-rank p = 0.686). Median and 1-year survival were 7.3 months and 26%, respectively, for PPX versus 6.6 months and 26% for the control arm. There was a nonsignificant trend toward improved survival in women in the PPX arm compared with standard single agents (HR = 0.65; p = 0.069). The most frequent grade 3/4 adverse events in the treatment versus control arm were dyspnea (13% versus 17%, respectively) and fatigue (10% versus 9%). Grade 3/4 neutropenia and anemia were reduced in the PPX arm (2% versus 8% and 3% versus 9%, respectively). Neuropathy, a taxane-specific toxicity, was more common in the PPX arm; grade 3 neuropathy was limited to 3%.ConclusionsSingle-agent PPX, dosed at 175 mg/m2, is active and well tolerated in PS 2 patients with advanced NSCLC. Patients on PPX required fewer red blood cell transfusions, hematopoietic growth factors, opioid analgesics, and clinic visits than patients receiving gemcitabine or vinorelbine

Phase III trial comparing paclitaxel poliglumex (CT-2103, PPX) in combination with carboplatin versus standard paclitaxel and carboplatin in the treatment of PS 2 patients with chemotherapy-naive advanced non-small cell lung cancer

Free to read at publisher's site. INTRODUCTION: Performance status (PS) 2 patients with non-small cell lung cancer (NSCLC) experience more toxicity, lower response rates, and shorter survival times than healthier patients treated with standard chemotherapy. Paclitaxel poliglumex (PPX), a macromolecule drug conjugate of paclitaxel and polyglutamic acid, reduces systemic exposure to peak concentrations of free paclitaxel and may lead to increased concentrations in tumors due to enhanced vascular permeability. METHODS: Chemotherapy-naive PS 2 patients with advanced NSCLC were randomized to receive carboplatin (area under the curve = 6) and either PPX (210 mg/m/10 min without routine steroid premedication) or paclitaxel (225 mg/m/3 h with standard premedication) every 3 weeks. The primary end point was overall survival. RESULTS: A total of 400 patients were enrolled. Alopecia, arthralgias/myalgias, and cardiac events were significantly less frequent with PPX/carboplatin, whereas grade ≥3 neutropenia and grade 3 neuropathy showed a trend of worsening. There was no significant difference in the incidence of hypersensitivity reactions despite the absence of routine premedication in the PPX arm. Overall survival was similar between treatment arms (hazard ratio, 0.97; log rank p = 0.769). Median and 1-year survival rates were 7.9 months and 31%, for PPX versus 8 months and 31% for paclitaxel. Disease control rates were 64% and 69% for PPX and paclitaxel, respectively. Time to progression was similar: 3.9 months for PPX/carboplatin versus 4.6 months for paclitaxel/carboplatin (p = 0.210). CONCLUSION: PPX/carboplatin failed to provide superior survival compared with paclitaxel/carboplatin in the first-line treatment of PS 2 patients with NSCLC, but the results with respect to progression-free survival and overall survival were comparable and the PPX regimen was more convenient. © 2008International Association for the Study of Lung Cancer