Search

Purpose: Monopolar spindle 1 (MPS1) kinase inhibitor, BAY 1217389 (BAY) synergizes with paclitaxel. This phase I study assessed the combination of BAY with paclitaxel using a novel randomized continuous reassessment method (rCRM) to improve dose determination. Patients and Methods: Patients with solid tumors were randomized to receive oral BAY (twice daily 2-days-on/5-days-off) with weekly paclitaxel (90 mg/m2) or paclitaxel monotherapy in cycle 1. Dose escalation was guided by CRM modeling. Primary objectives were to assess safety, establish the MTD of BAY, and to evaluate the pharmacokinetic profiles for both compounds. Simulations were performed to determine the contribution of the rCRM for dose determination. Results: In total, 75 patients were enrolled. The main dose-limiting toxicities were hematologic toxicities (55.6%). The MTD of BAY was established at 64 mg twice daily with paclitaxel. Inclusion of a control arm enabled the definitive attribution of grade ≥3 neutropenia to higher BAY exposure [AUC0–12 (P< 0.001)]. After determining the MTD, we included 19 patients with breast cancer at this dose for dose expansion. Other common toxicities were nausea (45.3%), fatigue (41.3%), and diarrhea (40.0%). Overall confirmed responses were seen in 31.6% of evaluable patients. Simulations showed that rCRM outperforms traditional designs in determining the true MTD. Conclusions: The combination of BAY with paclitaxel was associated with considerable toxicity without a therapeutic window. However, the use of the rCRM design enabled us to determine the exposure–toxicity relation for BAY. Therefore, we propose that the rCRM could improve dose determination in phase I trials that combine agents with overlapping toxicities.

Purpose: BAY1436032, an inhibitor of mutant isocitrate dehydrogenase 1 (mIDH1), was active against multiple IDH1-R132X solid tumors in preclinical models. This first-in-human study was designed to determine the safety and pharmacokinetics of BAY1436032, and to evaluate its potential pharmacodynamics and antitumor effects. Patients and Methods: The study comprised of dose escalation and dose expansion cohorts. BAY1436032 tablets were orally administered twice daily on a continuous basis in subjects with mIDH1 solid tumors. Results: In dose escalation, 29 subjects with various tumor types were administered BAY1436032 across five doses (150–1,500 mg twice daily). BAY1432032 exhibited a relatively short half-life. Most evaluable subjects experienced target inhibition as indicated by a median maximal reduction of plasma R-2-hydroxyglutarate levels of 76%. BAY1436032 was well tolerated and an MTD was not identified. A dose of 1,500 mg twice daily was selected for dose expansion, where 52 subjects were treated in cohorts representing four different tumor types [lower grade glioma (LGG), glioblastoma, intrahepatic cholangiocarcinoma, and a basket cohort of other tumor types]. The best clinical outcomes were in subjects with LGG (n = 35), with an objective response rate of 11% (one complete response and three partial responses) and stable disease in 43%. As of August 2020, four of these subjects were in treatment for >2 years and still ongoing. Objective responses were observed only in LGG. Conclusions: BAY1436032 was well tolerated and showed evidence of target inhibition and durable objective responses in a small subset of subjects with LGG.

Background Giant-cell tumours of bone (GCTB) are RANK/RANK-ligand (RANKL) positive, aggressive and progressive osteolytic tumours. Denosumab, a RANKL inhibitor, was FDA-approved for adults and skeletally mature adolescents with unresectable GCTB or when surgical resection is likely to result in severe morbidity. Data on long-term toxicity and activity of denosumab monthly ‘GCTB-schedule’ (120 mg per 12/year, 1440 mg total dose/year) are lacking. Methods Patients with GCTB receiving denosumab, 120 mg on days 1, 8, 15, 29 and every 4 weeks thereafter, from 2006 to 2015 treated in two centres were included. Long-term toxicity was evaluated. Results Ninety-seven patients were identified. 43 patients underwent resection of the tumour with a median time on denosumab treatment of 12 months (range 6–45 months). Fifty-four patients had unresectable GCTB's (male/female 23/31, median age 35 years [range: 13–76 years], 26% presented with lung metastases, 31% had primary tumor located to the spine, 63% were relapsed after previous surgery) with a median time on denosumab of 54 months (9–115 months). In the unresectable GCTB group, tumour control and clinical benefits were observed in all patients undergoing denosumab, whereas 40% of patients discontinuing denosumab had tumour progression after a median of 8 months (range 7–15 months). Adverse events Overall, six (6%) patients developed osteonecrosis of jaw (ONJ): 1/43 (2%) in the resectable group, 5/54 (9%) in the unresectable group, with a 5-year ONJ-free survival of 92% (95% CI 84–100). Only patients with prolonged treatment experienced mild peripheral neuropathy (6/54, 11%), skin rash (5/54, 9%), hypophosphataemia (2/54, 4%) and atypical femoral fracture (2/54, 4%). Conclusions Prolonged treatment with denosumab has sustained activity in GCTB, with a mild toxicity profile. The dose-dependent toxicity observed recommends a careful and strict monitoring of patients who need prolonged treatment. Decreased dose-intensity schedules should be further explored in unresectable GCTB.

Introduction: Soft tissue sarcomas (STS) comprise a group of uncommon mesenchymal tumors of heterogeneous differentiation. For advanced STS, single-agent doxorubicin or doxorubicin-based combinations are commonly used, but at serious risk of cumulative cardiotoxicity. In addition, doxorubicin is the sheet anchor drug for many malignancies, both solid and hematologic.Areas covered: Aldoxorubicin, a doxorubicin prodrug currently in development, was designed to bind covalently to serum albumin and remains conjugated until transported to an acidic environment, such as the tumor site. We review the novel mechanism of action and the published pharmacokinetic, safety and efficacy data from Phase I, Ib/II and II clinical studies of aldoxorubicin in patients with advanced solid tumors, including advanced STS.Expert opinion: Chemical modification of doxorubicin, an effective but cardiotoxic chemotherapy drug, to aldoxorubicin has yielded a notable improvement in patient outcomes. This small step in drug chemistry m...

BACKGROUND Aldoxorubicin, a prodrug of doxorubicin, covalently binds to serum albumin, allowing for the administration of much higher doses of doxorubicin in a previous clinical study. The current phase 1B/2 study evaluated the safety of aldoxorubicin, including preliminary efficacy and safety of its maximum tolerated dose (MTD). METHODS Patients aged 18 to 70 years with recurrent/refractory malignant solid tumors received aldoxorubicin at a dose of 230 mg/m2, 350 mg/m2, or 450 mg/m2 (170 mg/m2, 260 mg/m2, or 335 mg/m2 doxorubicin equivalents, respectively) by intravenous infusion once every 21 days for up to 8 consecutive cycles. RESULTS A total of 25 patients were enrolled, including 17 patients (68%) with advanced soft tissue sarcoma (STS). The MTD of aldoxorubicin was 350 mg/m2; dose-limiting toxicities included grade 4 neutropenia and grade 3 febrile neutropenia (NCI CTCAE v4.0). Drug-related adverse events included myelosuppression, nausea, fatigue, alopecia, stomatitis, vomiting, and oropharyngeal pain. No clinically significant cardiac toxicities were reported. Seven patients (28%) had elevated serum troponin levels while taking part in the study, but these elevations were not clinically significant or associated with cardiac findings. A partial response was achieved in 20% of patients, and stable disease was reported in 40% of patients. The median progression-free survival was 4.80 months, and the median overall survival was 11.25 months. Among patients with STS who were treated at the MTD (13 patients), a partial response was achieved in 38% and stable disease in 46%; the median progression-free survival was 11.25 months and the median overall survival was 21.71 months. CONCLUSIONS Aldoxorubicin at a dose of 350 mg/m2 administered once every 21 days for up to 8 cycles was found to be acceptably safe and demonstrated preliminary efficacy in patients with advanced solid tumors, including STS. Further investigation of aldoxorubicin is ongoing. Cancer 2015;121:570–579. © 2014 American Cancer Society.

ATI-1123 is a liposomal formulation of docetaxel and may be administered without the premedications and hypersensitivity reactions. This Phase I study examines the safety, tolerability, pharmacokinetics (PKs), and antitumor activity of ATI-1123.Patients with advanced solid malignancies received escalating doses of ATI-1123 intravenously over 1-h every 3 weeks. The dosing commenced using an accelerated titration design and was followed by a modified 3 + 3 Fibonacci schema to determine maximally tolerated dose (MTD). Plasma was analyzed for encapsulated/non-encapsulated docetaxel; PK analyses were performed using model independent method. Response was assessed using RECIST criteria.In total, 29 patients received doses ranging from 15 to 110 mg/m(2). At 110 mg/m(2), two of six patients experienced dose-limiting toxicities including grade 3 stomatitis and febrile neutropenia. The 90 mg/m(2) cohort was expanded to ten patients and identified as the MTD. The most common adverse events were fatigue, nausea, neutropenia, anemia, anorexia, and diarrhea. ATI-1123 exhibited linear and dose proportional PKs. One patient with lung cancer had confirmed partial response, and stable disease was observed in 75 % patients.ATI-1123 demonstrated an acceptable tolerability and favorable PK profile in patients with solid tumors. Our results provide support for Phase II trials to determine the antitumor activity of this drug.

Introduction Effective therapies after failure of treatment with anthracyclines and taxanes are needed for patients with metastatic breast cancer. Dinaciclib (MK-7965, formerly SCH727965), a small-molecule cyclin-dependent kinase inhibitor, has demonstrated antitumor activity in phase I studies with solid-tumor patients. This phase II trial was designed to assess the efficacy and safety of dinaciclib compared with that of capecitabine in women with previously treated advanced breast cancer. Patients and Methods Patients were randomized to receive either dinaciclib at 50 mg/m 2 , administered as a 2-hour infusion every 21 days, or 1250 mg/m 2 capecitabine, administered orally twice daily in 21-day cycles. Results An unplanned interim analysis showed that the time to disease progression was inferior with dinaciclib treatment compared with capecitabine treatment; therefore, the trial was stopped after 30 patients were randomized. Dinaciclib treatment demonstrated antitumor activity in 2 of 7 patients with estrogen receptor–positive and human epidermal growth factor receptor 2–negative metastatic breast cancer (1 confirmed and 1 unconfirmed partial response), as well as acceptable safety and tolerability. Grade 3 or 4 treatment-related adverse events were common and included neutropenia, leukopenia, increase in aspartate aminotransferase, and febrile neutropenia. Population pharmacokinetic model–predicted mean dinaciclib exposure (area under the concentration-time curve extrapolated to infinity [AUC [I] ]) at 50 mg/m 2 was similar to that observed in a previous phase I trial, and no drug accumulation was observed after multiple-dose administration. Conclusion Although dinaciclib monotherapy demonstrated some antitumor activity and was generally tolerated, efficacy was not superior to capecitabine. Future studies may be considered to evaluate dinaciclib in select patient populations with metastatic breast cancer and in combination with other agents.

Melanomas are vascular tumors with a high incidence of BRAF mutations driving tumor proliferation. Complete inhibition of vascular endothelial growth factor (VEGF) signaling has potential for enhanced antitumor efficacy.Patients with advanced melanoma and adequate organ function were eligible. Sorafenib was given orally at 200 mg BiD for 5 days every week; bevacizumab was administered 5 mg/kg intravenously every 14 days. The primary objective was to determine clinical biological activity. The secondary objectives were safety, tolerability, and time to progression (TTP). Pharmacodynamic analysis included serum VEGF and soluble VEGF receptor-1 and VEGF receptor-2 performed at baseline, C1D15 and C2D1. The study was terminated during the first stage of a Simon two-stage design, after 14 of planned 21 subjects were enrolled.Of the 14 patients who received treatment, no objective tumor responses were observed. Stable disease (SD) ≥16 weeks was observed in 57 % patients, including three patients with SD lasting ≥1 year. Median TTP was 32 weeks. The most frequently reported drug-related adverse events (AEs) were hand-foot syndrome (57.1 %), fatigue (57.1 %), hypertension (64.3 %), and proteinuria (35.7). Grade 3/4 drug-related AEs were hypertension (14.2 %), hand-foot syndrome, proteinuria, and thrombocytopenia (7 % each). Patients with low VEGF (300 pg/ml) experienced longer TTP than those with high VEGF [median 50 vs. 15 weeks, p = 0.02). A similar pattern was seen for VEGFR1 and VEGFR2, although it did not reach statistical significance.Combined VEGF/VEGFR blockade using bevacizumab with sorafenib shows clinical activity. The linkage between VEGF levels and time to tumor progression needs further exploration.

GRN1005 is a novel peptide–drug conjugate composed of paclitaxel covalently linked to a peptide, angiopep-2, that targets the low-density lipoprotein receptor-related protein 1. This first-in-human study evaluated the safety, tolerability, pharmacokinetics, and efficacy of GRN1005 in patients with advanced solid tumors. Patients in sequential cohorts (one patient per cohort until grade 2 toxicity, then 3 + 3 design) received intravenous GRN1005 at escalating doses between 30 and 700 mg/m2 once in every 21 days. In the maximum tolerated dose (MTD) expansion group, patients were required to have brain metastases. Fifty-six patients received GRN1005, including 41 with brain metastases (median number of prior therapies = 4). MTD was 650 mg/m2; the main dose-limiting toxicity was myelosuppression. Sixteen of 20 patients dosed at the MTD had brain metastases. Pharmacokinetics was dose linear and the mean terminal-phase elimination half-life was 3.6 hours. No evidence of accumulation was observed after repeat dosing. No anti-GRN1005 antibodies were detected. Five of the 20 patients (25%) dosed at 650 mg/m2 (MTD), three of whom had previous taxane therapy, achieved an overall partial response (breast, n = 2; non–small cell lung cancer, n = 2; and ovarian cancer, n = 1); responses in all five patients were also accompanied by shrinkage of brain lesions (−17% to −50%). In addition, six patients (11%; doses 30–700 mg/m2) experienced stable disease that lasted 4 months or more. GRN1005 was well tolerated and showed activity in heavily pretreated patients with advanced solid tumors, including those who had brain metastases and/or failed prior taxane therapy. Mol Cancer Ther; 11(2); 308–16. ©2011 AACR.

The mammalian target of rapamycin (mTOR) is a protein kinase that functions as a key regulator of cell growth, proliferation and differentiation, cell-cycle progression, angiogenesis, protein degradation, and apoptosis. Following activation by a number of oncogenic signals such as growth factors, energy and nutrients, mTOR stimulates several downstream effectors including the 40S ribosomal protein S6 kinase (p70s6k) and the eukaryotic initiation factor 4 E binding protein-1 (4 EBP-1), as well as a complex network of regulatory loops. Activation of the mTOR pathway plays a critical role in the development of many tumor types, including renal cell and breast carcinomas, neuroendocrine tumors, and sarcomas. Bone and soft tissue sarcomas are rare, heterogeneous tumors that are curable by local treatments if diagnosed at early stages; however advanced or metastatic sarcomas are rarely curable and very few drugs are efficacious in this setting. Several disruptions in phosphatidylinositol-3 kinase (PI3K)-Akt-mTOR signaling are associated with malignant transformation or progression in various sarcoma sub-types. The PI3K-Akt-mTOR pathway is therefore an exciting target for therapy of sarcomas, and its blockade represents an opportunity to improve outcomes in this poor-prognosis disease. Early studies with mTOR inhibitors have demonstrated promising antitumor activity in patients with metastatic sarcoma who have failed standard treatments. This article discusses the mTOR signaling pathway and summarizes the clinical experience with mTOR inhibitors in patients with advanced or metastatic sarcoma.

Purpose: To determine the maximum tolerated dose (MTD), safety, pharmacokinetics, pharmacodynamics, immunogenicity, and preliminary antitumor activity of CT-322 (BMS-844203), a VEGFR-2 inhibitor and the first human fibronectin domain–based targeted biologic (Adnectin) to enter clinical studies. Experimental Design: Patients with advanced solid malignancies were treated with escalating doses of CT-322 intravenously (i.v.) weekly (qw), or biweekly (q2w). Plasma samples were assayed for CT-322 concentrations, plasma VEGF-A concentrations, and antidrug antibodies. Results: Thirty-nine patients completed 105 cycles of 0.1 to 3.0 mg/kg CT-322 i.v. either qw or q2w. The most common treatment-emergent grade 1/2 toxicities were fatigue, nausea, proteinuria, vomiting, anorexia, and hypertension. Grade 3/4 toxicities were rare. Reversible proteinuria, retinal artery, and vein thrombosis, left ventricular dysfunction, and reversible posterior leukoencephalopathy syndrome were dose limiting at 3.0 mg/kg. The MTD was 2 mg/kg qw or q2w. CT-322 plasma concentrations increased dose proportionally. Plasma VEGF-A levels increased with dose and plateaued at 2 mg/kg qw. Anti–CT-322 antibodies developed without effects on pharmacokinetics, VEGF-A levels, or safety. Minor decreases in tumor measurements occurred in 4 of 34 evaluable patients and 24 patients had stable disease. Conclusions: CT-322 can be safely administered at 2 mg/kg i.v. qw or q2w and exhibits promising antitumor activity in patients with advanced solid tumors. The absence of severe toxicities at the MTD, demonstration of plasma drug concentrations active in preclinical models, and clinical pharmacodynamic evidence of VEGFR-2 inhibition warrant further development of CT-322 and suggest strong potential for Adnectin-based targeted biologics. Cancer Res; 17(2); 363–71. ©2011 AACR. Clin Cancer Res; 17(2); 363–71. ©2011 AACR.

11519Background: Patients (pts) with relapsed Ewing sarcoma (ES) have a poor outcome. New therapeutic agents are needed. L is a new anticancer drug that blocks transcription and induces DNA double-...

e23568Background: Immune checkpoint inhibitors revive pre-existing immune responses that are suppressed in cancer. To restore tumor surveillance that is lost in cancer patients, a tumoricidal agent...

TPS11589Background: PEComas are rare mesenchymal tumors with a female predominance, composed of epithelioid cells that show a focal association with blood vessel walls and usually express both mela...

2537Background: Here we present a study combining BAY1217389 (BAY), a potent MPS-1 kinase inhibitor with a backbone chemotherapy paclitaxel. Since we expected overlapping toxicities we sought to im...

40 Background: To restore innate tumor surveillance that is lost in cancer patients, a tumoricidal agent may have synergistic activity with an immune checkpoint inhibitor. Herein, we report on a retrospective analysis of our clinical experience using trabectedin, an alkylating agent, and nivolumab, a PD-1 inhibitor in advanced soft tissue sarcoma. Methods: Twenty previously treated STS patients received trabectedin (1.5 mg/m2 continuous intravenous infusion, CIV, for 24 hours) every 3 weeks, and nivolumab (3 mg/kg IV over 30 minutes) every 2 weeks. Safety/toxicity was analyzed using the NIH/NCI CTCAE v.4.03. Tumor responses were assessed by RECIST v1.1 and immune-related response criteria (irRECIST). Results: Histologic subtypes in 20 patients include undifferentiated pleomorphic sarcoma (UPS; n = 7), leiomyosarcoma (n = 5), synovial sarcoma (n = 2), myxoid liposarcoma (n = 4) and chondrosarcoma (n = 2). All patients had metastatic disease and a median of 4 lines of prior chemotherapy. Safety analysis (n = 20): Grade 3 treatment emergent adverse events include anemia (n = 2), fatigue (n = 1), decreased platelet count (n = 1), decreased granulocyte count (n = 1) and increased creatine kinase (n = 1). Efficacy analysis (n = 17): Seventeen patients were followed for at least 6 months and their results are reported here. There were 4 partial responses (UPS = 1, myxoid liposarcoma = 1, chondrosarcoma = 1, leiomyosarcoma = 1), 7 stable disease, and 6 progressive disease, with best overall response rate of 23.5%, median progression free survival (PFS) of > 11.6 months (range: 2.3- > 16.9 months), median overall survival (OS) of > 14.2 months (4.5- > 24.0 months), 6 month PFS rate of 64.7%, and 6 month OS rate of 94.1%. In a Phase 3 study, the median PFS was 4.2 months using trabectedin alone (Demetri et al., 2015). Conclusions: Taken together, the data suggest that paired administration of trabectedin and nivolumab is safe, and that this chemo-/immuno-therapy approach has synergistic activity.

Sarcomas are a group of heterogeneous tumors that arise from mesenchymal tissue and account for approximately 1% of all adult solid malignancies diagnosed, although its incidence approaches 20% in pediatric cancers. Characterization of molecular abnormalities in patients with sarcomas, in particular the up-regulation of the receptor tyrosine kinase and the PI3K-AKT-mTOR pathway, loss or deletions of retinoblastoma (Rb) and p53 gene, increased VEGF expression and angiogenesis, dysregulation of apoptosis through Bcl-2 overexpression, along with oncogene mutations and activations, such as c-KIT in Gastrointestinal stromal tumors (GISTs), makes treatment with novel biological therapies a promising option. This review focuses on the molecular heterogeneity of soft tissue and bone sarcomas, novel biological therapies currently in clinical trials to target the various molecular pathways, and the potential biological agents in pre-clinical and early clinical development.

Despite significant advances in the treatment of hematological malignancies over the last decade, morbidity and mortality from these disorders remain high. New discoveries in the pathogenesis of these malignancies have led to better understanding of these diseases and new thinking in drug development. mTOR is a downstream effector of the PI3K/Akt (protein kinase B) signaling pathway that mediates cell survival and proliferation and is known to be deregulated in many cancers. Preclinical activity of mTOR inhibitors has been very promising in various hematological malignancies. Rapamycin analogs with relatively favorable pharmaceutical properties, including temsirolimus (CCI-779), everolimus (RAD001) and deforolimus (AP23573), are under clinical evaluations in patients with hematologic malignancies. They have shown encouraging results thus far and a favorable toxicity profile. Their utility, mainly as cytostatic agents, needs to be further explored in combination with pre-existing chemotherapeutic agents for various hematological malignancies.

Mammalian target of rapamycin (mTOR) has emerged as an important target for cancer therapy. Rapamycin has a distinct, well-documented toxicity profile and most of the toxicity data has been reported in patients with organ transplantation. Newer mTOR inhibitors have slightly different pharmacokinetic properties, yet they present toxicity profiles similar to rapamycin. Most of these toxicities are mild to moderate in severity and can be managed clinically by dose modification and supportive measures. Mucositis and pneumonitis are the most commonly reported toxicities, but they rarely lead to treatment discontinuation. Pathogenesis of pneumonitis is uncertain, but various hypotheses have been suggested, including cell-mediated immune response to the drug.

11021Background: Giant cell tumours of bone (GCTB’s) are RANK-ligand (RANK-L) positive, aggressive and progressive osteolytic tumors. Denosumab, a RANK-L inhibitor, was FDA-approved for adults and ...

Background: Entrectinib is a potent, CNS-penetrant, oral inhibitor of the tyrosine kinases TRKA/B/C (encoded by the genes NTRK1/2/3, respectively), ROS1, and ALK with IC50s < 2 nM (biochemical kinase assay). Two Phase 1 studies ALKA-372-001 and STARTRK-1 have enrolled more than 130 patients with advanced or metastatic solid tumors harboring TRKA/B/C, ROS1, or ALK molecular alterations, with or without CNS disease. Previously, we reported an objective response rate of 79% in 24 tyrosine kinase inhibitor-naïve patients with TRK, ROS1, or ALK gene fusions who were treated at doses that achieved therapeutic exposures consistent with the Recommended Phase 2 Dose (RP2D) (Drilon et al, AACR 2016). Entrectinib was well tolerated, with predominantly Grades 1 or 2 adverse events that were reversible with dose modification. Responses were observed in NSCLC, colorectal cancer, mammary analog secretory carcinoma, melanoma, and renal cell carcinoma, as early as 4 weeks after starting treatment and lasting as long as > 2 years. Notably, a complete CNS response was achieved in a patient with SQSTM1-NTRK1-rearranged lung cancer. Methods: STARTRK (Studies of Tumor Alterations Responsive to Targeting Receptor Kinases)-2 is a potentially registration-enabling Phase 2 basket study of entrectinib for the treatment of patients with advanced solid tumors that harbor a TRK, ROS1, or ALK gene fusion. In order to determine enrollment eligibility and assignment to a specific tumor type basket, patients are screened for gene fusions either locally, including by ctDNA, or centrally at Ignyta’s CLIA/CAP diagnostic laboratory using next generation sequencing. The study’s eligibility criteria were designed to maximize enrollment of these rare patients by allowing CNS disease, Eastern Cooperative Oncology Group (ECOG) performance status 2, and any prior line of therapy, with the exception of TRK, ROS1, or ALK inhibitors. Patients with ALK- or ROS1-rearranged NSCLC who had previously been treated with crizotinib and experienced CNS-only progression are also eligible. In addition, a “non-evaluable” basket allows enrollment of patients confirmed to have gene fusions who do not meet all the inclusion or exclusion criteria. Entrectinib is administered orally on a continuous daily dosing regimen, at a dose of 600 mg once-daily in repeated 4-week cycles. Safety is assessed by monitoring of adverse events, laboratory tests, and clinic visits. Tumor assessments (computed tomography (CT) or magnetic resonance imaging (MRI)) of the chest, abdomen, pelvis (depending on tumor type), plus bone and/or brain as applicable, are performed at the end of Cycle 1 and every 8 weeks thereafter. All CT and MRI scans are read by a central independent imaging laboratory using the Response Evaluation Criteria In Solid Tumors (RECIST) v1.1 and the Response Assessment in Neuro-Oncology Criteria (RANO) or RANO - Brain Metastases (RANO-BM), as applicable, for patients with primary or secondary CNS disease, respectively. Blood and tissue are collected at the time of progression for biomarker analyses for potential mechanisms of resistance to entrectinib. Patients remain on study treatment until documented radiographic progression as assessed by blinded independent central review (BICR), development of unacceptable toxicity, or withdrawal of consent. Citation Format: Alexander Drilon, Kamalesh Kumar Sankhala, Stephen V. Liu, Byoung Chul Cho, Collin Blakely, Cheng E. Chee, Marwan Fakih, Jonathan Polikoff, Zachary Hornby, Lisa Schechet, David Luo, Edna Chow Maneval, Pratik S. Multani, Robert C. Doebele. STARTRK-2: A global phase 2, open-label, basket study of entrectinib in patients with locally advanced or metastatic solid tumors harboring TRK, ROS1, or ALK gene fusions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT060. doi:10.1158/1538-7445.AM2017-CT060

11051 Background: Aldoxorubicin (A) has demonstrated superior anti-tumor efficacy and lack of cumulative cardiac toxicity in multiple studies. A is doxorubicin (D) with a linker which rapidly binds in vivo to albumin after iv. We studied the combination of A administered on Day 1 with continuous infusion (CI) of ifosfamide/Mesna (I-M) days 1-14, as first line therapy or second line therapy in patients with soft tissue sarcomas (STS) to evaluate efficacy and toxicity. Methods: 27 patients have entered the study at 250 mg/m2 ( 185 mg/m2 D equiv) administered on Day 1. I-M (1 g/m2 of each per day) was given up to 14 days as a CI via an out-patient portable pump. Chemotherapy cycles were repeated at 28 day interval. I-M was limited to a maximum of 6 cycles to avoid cumulative marrow toxicity, but A was continued per investigator decision in responding or SD patients for clinical benefit. Subjects were followed for tumor response (RECIST 1.1) by CT scans and echocardiogram/ECG for cardiac toxicity every 8 weeks along with standard labs. Enrollment continues up to 50 patients. Results: Demographics: Leiomyosarc. = 20%, liposarc. = 20%, synovial sarc. = 20%, rhabdosarc. = 8%, others = 32%. Caucasian, 11% Asian, 4% Black; 67% no prior tx, 26% 1 prior tx, 7% > 1 prior tx; Median cum. A = 1000 mg/m2 (740 mg/m2 D eq.; 185-4070 mg/m2 D eq.); I = 6.9 g/m2 (2.1-12.6 g/m2). Best response: 42% PR, 58% SD. Median PFS not reached. 10 subjects with either PR or SD had surgery to remove accesible tumors. Range of tumor necrosis = 70 to > 95%. Grade 3/4 AEs: neutropenia = 78%, febrile neutropenia = 9%, thrombocytopenia = 22%, anemia = 65%, nausea = 4%. Related SAEs = 4 (febrile neutropenia (2), pyrexia, stomatitis). No tx related deaths. No clinically significant cardiac AEs, no decrease in LVEF > 20% Conclusions: A can be administered for prolonged periods and safely with CI ifosfamide/mesna and achieves high ORR and SD with substantial tumor necrosis. Clinical trial information: NCT02235701.

11078 Background: TGCTis a proliferative, neoplastic joint disease that presents as single nodule (local) or multiple nodules (diffuse D-TGCT). Localized overexpression of colony stimulating factor 1 (CSF1) leads to recruitment of cells expressing the CSF1 receptor (CSF1R), formation of a tumor and inflammation of joints and tendons. Cabira is a monoclonal antibody that inhibits the interaction of the CSF1 and IL-34 ligands with their shared receptor CSF1R. Methods: This Ph 1/2 study is evaluating the safety and efficacy of cabira monotherapy administered IV Q 2wk for 6 mo in patients (pts) with D-TGCT. Eligible pts have inoperable D-TGCT or tumor for which resection would cause unacceptable morbidity. Response is evaluated by MRI, pt reported outcomes, and Ogilvie-Harris (O-H) score (which combines pain, synovitis, range of motion and functional capacity on a scale of 0-12). Results: As of 15 Dec 2016, 22 pts received ≥ 1 dose of cabira at 1, 2 or 4mg/kg. Dose-related exposure increase and significant reduction in target peripheral monocytes were observed. No dose limiting toxicity was identified. 4 mg/kg was chosen for Ph2 based on efficacy, tolerability, and PK. AEs ≥ Gr 2 ( > 10%) were CK elevation 46%, rash and other skin disorders 36%, fatigue 23%, and periorbital/peripheral/face edema 18% each. Gr 3 AEs in ≥ 2 pt were CK elevation (n = 8) and periorbital edema (n = 2). Four drug-related SAEs were reported in 3 pts; hypertension, fever, CRP elevation, and myocarditis. AEs of CK elevation were asymptomatic, improved to < 2X ULN after protocol mandated drug discontinuation and are a known on-target effect of CSF1R inhibition. An amendment was made during Phase 2 to allow dosing with higher CK levels Activity at 4 mg/kg was: 1PR and 1 CK discontinuation in 3 pts in Ph1; 4 PRs in 7 evaluable pts with 6 additional ongoing in Ph2. Positive functional status improvements by O-H score were noted in objective responders (from 2 to 7). Conclusions: The initial demonstration of objective and functional activity supports further development of cabiralizumab in pts with D-TGCT. Updated data from the ongoing Ph2 will be presented. NCT02471716 . Clinical trial information: NCT02471716.

11052Background: Trabectedin (T) is an anti-tumor agent used in the treatment of advanced soft-tissue sarcomas (STS). It interferes with DNA replication, causing double strand breaks and apoptosis,...

11016Background: P, a VEGFR TKI, is approved for advanced STS based on median PFS (mPFS) in the absence of CR. Endoglin is a receptor expressed on tumor vessels that is overexpressed in certain STS...

e22547Background: Ifosfamide (I)+ doxorubicin (D) is considered the most active treatment regimen for soft tissue sarcomas (STS). I is given as a 4-5 day infusion with D administered on Day 1 of ea...

2523Background: Aldoxorubicin (A) is a novel prodrug of doxorubicin (D) that binds covalently to albumin, accumulates in tumors and releases D under acidic conditions. It has demonstrated significant efficacy against soft tissue sarcomas in a phase 2b study versus D. Gemcitabine (G), when combined with various chemotherapies (albumin/paclitaxel nanoparticles, liposomal D) has demonstrated efficacy in patients with pancreatic, ovarian and lung cancers. It was hypothesized that A+G might possess synergistic activity against solid tumors. This study was designed to identifiy the major toxicities of this combination and establish its MTD. Methods: Adults who had relapsed or not responded to prior chemotherapies were eligible. Initial cohorts were (i) A 170 mg/m2+ G 900 mg/m2 ); (ii) A 250 mg/m2 + G 900 mg/m2; and (iii) A 200 mg/m2 + G 750 mg/m2. A was administered on Day 1 and G on Days 1 and 8 of each 21 day cycle. Safety was monitored continuously, cardiac function was assessed every 2 months by echocardiog...

Purpose Ridaforolimus is an inhibitor of mammalian target of rapamycin, an integral component of the phosphatidyl 3-kinase/AKT signaling pathway, with early evidence of activity in sarcomas. This multicenter, open-label, single-arm, phase II trial was conducted to assess the antitumor activity of ridaforolimus in patients with distinct subtypes of advanced sarcomas. Patients and Methods Patients with metastatic or unresectable soft tissue or bone sarcomas received ridaforolimus 12.5 mg administered as a 30-minute intravenous infusion once daily for 5 days every 2 weeks. The primary end point was clinical benefit response (CBR) rate (complete response or partial response [PR] or stable disease ≥ 16 weeks). Safety, progression-free survival (PFS), overall survival (OS), time to progression, and duration of response were also evaluated. Results A total of 212 patients were treated in four separate histologic cohorts. In this heavily pretreated population, 61 patients (28.8%) achieved CBR. Median PFS was 15.3 weeks; median OS was 40 weeks. Response Evaluation Criteria in Solid Tumors (RECIST) confirmed response rate was 1.9%, with four patients achieving confirmed PR (two with osteosarcoma, one with spindle cell sarcoma, and one with malignant fibrous histiocytoma). Archival tumor protein markers analyzed were not correlated with CBR. Related adverse events were generally mild or moderate and consisted primarily of stomatitis, mucosal inflammation, mouth ulceration, rash, and fatigue. Conclusion Single-agent ridaforolimus in patients with advanced and pretreated sarcomas led to PFS results that compare favorably with historical metrics. A phase III trial based on these data will further define ridaforolimus activity in sarcomas.

Standard therapy for advanced soft-tissue sarcoma has not changed substantially in decades, and patient prognosis remains poor. Aldoxorubicin, a novel albumin-binding prodrug of doxorubicin, showed clinical activity against advanced soft-tissue sarcoma in phase 1 studies.To evaluate efficacy and safety of aldoxorubicin vs doxorubicin in patients with advanced soft-tissue sarcoma.International, multicenter, phase 2b, open-label, randomized study at general community practices, private practices, or institutional practices. Between August 2012 and December 2013, 140 patients with previously untreated locally advanced, unresectable, or metastatic soft-tissue sarcoma were screened.Randomization (2:1) to aldoxorubicin 350 mg/m2 (dose equivalent to doxorubicin 260 mg/m2) or doxorubicin 75 mg/m2, administered once every 3 weeks for up to 6 cycles.Primary end point was progression-free survival. Secondary end points were 6-month progression-free survival, overall survival, tumor response rate, and safety. All efficacy end points were evaluated by independent and local review.A total of 126 patients were randomized, and 123 received aldoxorubicin (n = 83) or doxorubicin (n = 40). Median (range) patient age was 54.0 (21-77 years); 42 (34%) had leiomyosarcoma. By independent review, median progression-free survival was significantly improved (5.6 [95% CI, 3.0-8.1] vs 2.7 [95% CI, 1.6-4.3] months; P = .02) with aldoxorubicin compared with doxorubicin, as was the rate of 6-month progression-free survival (46% and 23%; P = .02). Median overall survival was 15.8 (95% CI, 13.0 to not available) months with aldoxorubicin and 14.3 (95% CI, 8.6-20.6) months with doxorubicin (P = .21). Overall tumor response rate (by Response Evaluation Criteria in Solid Tumors, version 1.1) by independent review was higher with aldoxorubicin than with doxorubicin (25% [20 patients, all partial response] vs 0%). Grade 3 or 4 neutropenia was more frequent with aldoxorubicin than with doxorubicin (24 [29%] vs 5 [12%]), but not grade 3 or 4 febrile neutropenia (12 [14%] vs 7 [18%]). No acute cardiotoxic effects were observed with either treatment, although left ventricular ejection fraction less than 50% occurred in 3 of 40 patients receiving doxorubicin.Single-agent aldoxorubicin therapy showed superior efficacy over doxorubicin by prolonging progression-free survival and improving rates of 6-month progression-free survival and tumor response. Aldoxorubicin therapy exhibited manageable adverse effects, without unexpected events, and without evidence of acute cardiotoxicity. Further investigation of aldoxorubicin therapy in advanced soft-tissue sarcoma is warranted.clinicaltrials.gov Identifier: NCT01514188.

Purpose: To evaluate the safety, pharmacokinetics, and antitumor activity of AMG 386, an investigational selective angiopoietin 1/2-neutralizing peptibody, in combination with FOLFOX-4 (F), carboplatin/paclitaxel (C/P), or docetaxel (D), in adult patients with advanced solid tumors. Experimental Design: Three cohorts of patients (F, n = 6; C/P, n = 8; D, n = 12) received one full cycle of chemotherapy alone during the pretreatment phase, followed by administration of AMG 386 10 mg/kg i.v. weekly in combination with chemotherapy until disease progression or intolerance. Safety and tolerability, tumor response, pharmacokinetic profiles, and biomarkers were assessed. Results: Twenty-six patients were enrolled; 22 received treatment with AMG 386. No dose-limiting toxicities or grade 3 or 4 adverse events related to AMG 386 were reported. The most common adverse events were diarrhea and hypomagnesemia (n = 3 each). One patient developed grade 2 hypertension and one had grade 1 subconjunctival eye hemorrhage. No neutralizing antibodies to AMG 386 were detected. There were no pharmacokinetic interactions between AMG 386 and F, C/P, or D. One patient receiving AMG 386 plus C/P for bladder cancer refractory to gemcitabine/cisplatin had a complete response at week 8. The remaining best tumor responses were partial response (n = 3, one from each cohort), stable disease ≥8 weeks (n = 13), and progressive disease (n = 1). Conclusions: Weekly administration of AMG 386 in combination with three common chemotherapy regimens was well tolerated in patients with advanced solid tumors. No pharmacokinetic interactions between AMG 386 and any of the tested chemotherapy regimens were noted. Promising antitumor activity was observed with all three treatment combinations. Clin Cancer Res; 16(11); 3044–56. ©2010 AACR.

The mammalian target of rapamycin (mTOR) is an intracellular protein with a key role in cellular protein synthesis and energy balance that influences many aspects of cell growth and proliferation, including differentiation, cell-cycle progression, angiogenesis, protein degradation and apoptosis. mTOR can be activated by numerous oncogenic signals, such as growth factor activation through the EGF, IGF and VEGF receptors, mutation and silencing of the PTEN tumor suppressor gene, activating mutations in the PI3K catalytic subunit, Akt amplification and the Ras–Raf–MEK pathway. Once activated, the cellular functions of mTOR are achieved through its downstream targets, 4E-BP1 and p70S6K1. The mTOR pathway can be further regulated through a negative feedback loop, which may lead to resistance to specific inhibitors of mTOR. This review will outline the mTOR signaling pathway, which is often activated in cancers and account for tumor proliferation and growth, highlight the rationale in targeting mTOR with a focus on the preclinical and clinical development of one of these inhibitors, deforolimus (AP23573, MK-8669), and discuss potential benefit and barriers to these agents being introduced in the clinic.

The outcome of patients with gastrointestinal stromal tumors has been dramatically improved by therapy with imatinib mesilate (imatinib mesylate), a KIT and platelet-derived growth factor (PDGFR) tyrosine kinase inhibitor. Unfortunately, the majority of patients eventually experience disease progression due to drug resistance. Recent elucidation of the mechanisms of resistance to imatinib, particularly the acquisition of secondary mutations of the KIT and PDGF receptors, has provided significant insight and potential for the development of novel therapies. This review discusses the efficacy of sunitinib, which is approved for the treatment of patients with imatinib-resistant tumors, and highlights a number of emerging second-generation receptor tyrosine kinase inhibitors that show therapeutic potential in imatinib-resistant patients. Also considered are several promising agents targeting pathways downstream of the constitutionally activated KIT and PDGF receptors. Strategies to overcome imatinib resistance by optimizing combination therapy and selecting specific kinase inhibitors based on the secondary mutations identified in tumors of individual patients are presented.

10573 Background: Gemcitabine and docetaxel chemotherapy protocols have proven efficacy in the treatment of metastatic soft tissue sarcomas. Doxorubicin is also a commonly used treatment both as a ...

10514 Background: The VEGFR inhibitor pazopanib is approved for the treatment of advanced STS. Resistance to pazopanib is a challenge in the treatment of STS, and endoglin (CD105) activation may be an important resistance mechanism. Endoglin is an angiogenic receptor expressed on proliferating tumor vessels, which is upregulated following VEGF inhibition and expressed on certain STS subtypes, including angiosarcoma. A phase Ib study of TRC105, an anti-endoglin antibody, in combination with pazopanib was performed in patients (pts) with advanced STS. Methods: Heavily-pretreated STS pts with leiomyosarcoma (11); angiosarcoma (2); synovial sarcoma (2); epithelioid sarcoma (1); myxofibrosarcoma (1); epithelioid hemangioendothelioma (1); and unclassifiable high grade sarcoma (2), ECOG PS 0-1, were treated with infusional TRC105 weekly in two cohorts (8mg/kg and 10mg/kg). TRC105 was initiated following a 2 to 4 week lead-in period of pazopanib starting at 800 mg PO daily. Results: Twenty pts (median age = 57; M...

10528 Background: GCTB are aggressive osteolytic tumors, which are characterized by local bone destruction and soft tissue invasion. There have been limited non-surgical treatments, including radiation therapy. However, an unacceptable rate of post radiation sarcomas has been well established. Such tumors have osteoclast like giant cells/stromal cells that express surface RANK ligand. Denosumab is an FDA approved drug used in the treatment of unresectable GCTB or GCTB with severe morbidity related surgery. It is a monoclonal antibody that targets the RANK ligand characteristic to GCTB. We report our 8-year experience in the treatment of complex GCTB using denosumab. Methods: Review of 43 skeletally mature patients (N = 43) who were treated with subcutaneous (SC) denosumab for the treatment of GCTB, in whom surgery was not feasible without severe morbidity. Denosomab was dosed at 120 mg on days 1, 8, 15, 29, and every 4 weeks thereafter. CT, PET/CT, or MRI was used to determine radiographic disease burden,...

10546 Background: Aldoxorubicin (6-maleimidocaproic acid hydrazide) is a novel prodrug of doxorubicin that binds to the thiol group of cysteine-34 amino acid in circulating albumin. The circulating...

58 Background: GISTs are characterized by KIT/PDGFRA mutations. A range of multi-targeted tyrosine kinase inhibitors (TKIs) are available for treatment, however, resistance mechanisms inevitably emerge. Recent data (Boichuk, et al 2014) suggests the potential efficacy of various cytotoxic therapies that were identified as being able to effectively kill TKI-responsive and -resistant GIST cells. We sought to investigate the theranostic markers associated with non-TKI therapy options for their potential role in treatment of GIST. Methods: 147 GIST cases were evaluated. A multiplatform approach of biomarker testing was used and included a combination of sequencing (NGS, Sanger), protein expression (IHC) and gene amplification (ISH). Results: Multidrug resistance phenotype was found in 52-68% (PGP, MRP1). Tubulin-binding agents (taxanes, vinca alkaloids) may be of potential use due to the high frequency of low TUBB3 expression (72% or 39/54). Anthracyclines and topoisomerase inhibitors may be of potential benefit in 1/3 of patients based on expression of TOPO2A (32% or 32/99) and TOPO1 (34% or 37/110). Cytotoxic agents used in non-GIST solid tumors, may also be considered, based on high frequency of low expressin of MGMT (47% or 57/122), TS (70% or 76/109) and RRM1 (79% or 88/111). PTEN was intact (positive expression) in the majority of GIST (87%). Nine patients were examined for PD1/PDL1: 56% exhibited positive tumor infiltrating lymphocytes and 33% exhibited PDL1 tumor expression. Only one amplification event was observed: cMET (0/53), HER2 (0/69), EGFR (0/16), PIK3CA (0/1) and TOP2A (1/11). Mutational screening using a hot spot cancer panel (and Sanger sequencing for some genes) resulted in the detection of variants in only 10 genes, excluding KIT (97/132) and PDGFRA (5/55). Variants were detected in the following genes, in decreasing order of frequency: RB1, APC and JAK3 (2/55; 2/55; 2/57), PIK3CA (2/69) and ABL1, cMET, EGFR, KDR, VHL and BRAF (1/55, 1/57, 1/57, 1/57, 1/52, 1/78). Conclusions: A multi-platform approach of theranostic biomarkers identified therapies beyond TKIs for GIST. Various cytotoxics and non-KIT/PDGFRA targeted therapies were identified based on protein expression or gene variations.

10596 Background: Ifosfamide is commonly used to treat bone and soft tissue sarcomas (STS) and its efficacy appears to increase with doses >9g/m2/cycle. Due to the toxicity associated with bolus do...

11113 Background: AV-203 is an IgG1k humanized monoclonal antibody with high affinity and specificity for the anti-v-erb-b2 erythroblastic leukemia viral oncogene homolog 3 (ERBB3) receptor. Based ...

10502 Background: Doxorubicin (D) is the only approved first line therapy for most advanced soft tissue sarcomas (STS). Aldoxorubicin (A) consists of doxorubicin attached to an acid-sensitive linke...

2573 Background: IMGN853 is an antibody-drug conjugate (ADC) comprising a folate receptor 1 (FOLR1)-binding antibody and the potent maytansinoid, DM4. FOLR1 is over-expressed on many solid tumors, particularly EOC, endometrial cancer, non-small cell lung cancer (NSCLC), and clear-cell renal cell cancer. Methods: The primary study objectives are to determine the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D). Secondary objectives include evaluation of safety, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary efficacy. In dose escalation, patients with any type of FOLR1-expressing, refractory solid tumor may be enrolled. Once the MTD is defined, 3 expansion cohorts will evaluate patients with (1) primary platinum refractory or resistant EOC; (2) relapsed/refractory EOC, amenable to biopsy, and (3) relapsed/refractory NSCLC. Cohorts 2 and 3 will have IMGN853 PD assessment by pre-and post-dose tumor biopsy and by FLT-PET imaging, respectively. IMGN853 is given intravenously (IV) on Day 1 of each 21-day cycle. During dose escalation, an accelerated titration design was used. Responses are assessed using RECIST and GCIG criteria (as appropriate). Results: Eleven patients have been enrolled across 6 dose levels ranging from 0.15 to 5.0 mg/kg: 7 patients with EOC and 4 patients with endometrial cancer. No study drug-related serious adverse events (SAEs) or dose-limiting toxicity (DLT) have been reported. Among these 11 patients, 3 patients reported adverse events (AEs) considered study drug related; these were mild or moderate. At the 3.3 mg/kg dose level, one patient with serous EOC had an 82% reduction in CA125 (confirmation pending). The other 2 patients at this dose level, one with EOC and one with endometrial cancer, have stable disease. Drug exposure has been measured in 8 patients and has been found to generally increase linearly, with a half life at 3.3 mg/kg (3 patients) of approximately 4 days. Conclusions: IMGN853 is well tolerated at doses up to 3.3 mg/kg. Safety evaluation continues at 5 mg/kg and dose escalation is ongoing. Clinical trial information: NCT01609556.

2550 Background: Aldoxorubicin is a novel drug that covalently binds to albumin in the circulation with release in low pH environments. Preclinical studies in pancreatic and ovarian tumor xenograft models demonstrated that aldoxorubicin plus doxorubicin administered at 50% of their MTD provided complete and prolonged tumor remission in these models with less toxicity than each drug administered at their MTD. We evaluated the toxicity profile of a fixed dose of doxorubicin and escalating doses of aldoxorubicin in subjects with advanced solid tumors. Methods: Phase 1b open label, dose-escalation study of aldoxorubicin administered at either 175, 240 or 320 mg/m2 (130, 180, or 240 mg/m2 doxorubicin equivalents) iv + 35 mg/m2doxorubicin iv, both on Day 1 of 21 day cycles, for up to 8 cycles. The MTD is the dose level immediately below where 2/6 subjects experience a dose limiting toxicity (DLT) , or the maximum dose of 320 mg/m2aldoxorubicin. Additional subjects may be enrolled at the MTD to provide more safety data. Results: 10 subjects have been treated as of January 21, 2013. No DLT was observed and the MTD was defined as 320 mg/m2 aldoxorubicin and 35 mg/m2 doxorubicin iv administered on Day 1 of 21 day cycles. A median of 4.5 cycles have been received. 3/10 subjects were terminated due to either progressive disease (2) or death (1). No subject was terminated due to an adverse event. Grade 3 or 4 neutropenia was seen at all dose levels (8/10 subjects). 4/10 subjects exhibited grade 3 or 4 thrombocytopenia and 3/10 subjects had grade 3 or 4 anemia. Neutropenic fever occurred in 3/10 subjects. Other grade 3/4 adverse events seen in 2 or fewer subjects included fatigue, increased liver enzymes and dehydration. No significant mucositis or cardiotoxicity was observed. At this time the best response has been stable disease in 6/10 subjects and a partial response in 1 subject (malignant fibrous histiocytoma). Conclusions: The combination of aldoxorubicin (320 mg/m2)) + doxorubicin (35 mg/m2) can be safely administered to subjects with solid tumors. Hematologic toxicity is common and can be controlled with growth factors. The dose of aldoxorubicin is 90% of the MTD of aldoxorubicin administered as a single agent. Thus, doxorubicin does not appear to add to the toxicity of this combination. Clinical trial information: NCT01673438.

2609 Background: Liposomal (LIPO) docetaxel (DOCE) formulations may reduce hypersensitivity reactions, eliminate premedication requirements, have a broader therapeutic index, and enhance systemic DOCE exposure. ATI-1123 is a novel LIPO DOCE formulation utilizing human serum albumin that facilitates LIPO tumor targeting. We studied safety, tolerability, pharmacokinetics (PK) and tumor response of ATI-1123 in patients (pts) with advanced solid tumors. Methods: Pts enrolled had progressive disease after standard therapy, measurable disease (RECIST), ECOG ≤ 2, survival ≥ 3 mo. Dosing (1 hr infusion) began at 15 mg/m2 using an accelerated titration design, followed by a modified Fibonacci schema to MTD. Dosing was continued until pts had progressive disease or unacceptable toxicities. Plasma was analyzed for encapsulated / non-encapsulated DOCE using a validated assay. PK was determined by model independent methods. Results: To date, 19 pts were enrolled (median age 62 yr; range 40-80 yr; 58% male; 5 (26%) NSC...

Dinaciclib is a potent, selective inhibitor of CDKs 1, 2, 5, and 9 with preclinical activity in breast cancer cell lines and tumor xenografts. A randomized, multicenter, open-label phase 2 study was conducted to compare the efficacy of dinaciclib and capecitabine (1250 mg PO) in patients (pts) with advanced, previously treated breast cancer (BC). Dinaciclib 50 mg/m2 was administered by 2-hour i.v. infusion once every 21 days. Key inclusion criteria included ≤2 prior chemotherapy regimens, prior treatment with a taxane and anthracycline, and measurable disease. According to the original design, 20 pts were to be randomized 1:1 and thereafter pts were to be randomized using an adaptive Bayesian algorithm that adjusts the randomization ratio in favor of the more active arm. The protocol was amended to continue 1:1 randomization in lieu of the adaptive approach to obtain more experience with upfront dinaciclib. Patients were allowed to cross-over to dinaciclib after progressing on capecitabine. This design provides a comparison of dinaciclib versus capecitabine and an assessment of dinaciclib activity in patients who progressed on capecitabine. Time-to-progression (TTP) was the primary endpoint for pts receiving upfront treatment, and response rate (RR) was the primary endpoint for pts who crossed over to dinaciclib. Twenty-eight pts were treated (13 dinaciclib, 15 capecitabine). Data on 19 dinaciclib treated pts, including 6 that crossed over, are presented. Their median age was 53 (34-80) with a median of 2 (1-2) prior chemotherapy regimens and median ECOG performance status of 1(0-1). ER+/PR+/Her2 receptor status is available for 10/13 pts treated with dinaciclib, including five with ER+/PR+/Her2-, one with ER-/PR-/Her2-, two with ER-/PR-/Her2+ and two with ER+/PR-/Her2-. The median number of treatment cycles was 3 (1-11). 17 pts received more than one cycle of dinaciclib treatement. Investigators reported partial responses (PR) in 2/12 (17%) evaluable subjects receiving upfront dinaciclib; both with ER+/HER2- tumors. One confirmed PR had a complete resolution of a 4 cm chest wall mass. No responses were reported on the cross over arm. Four of fifteen (27%) evaluable subjects receiving capecitabine were reported to have PR. Analysis of TTP will be presented at the meeting. Treatment-related grade 1 and 2 toxicities, occurring in >30% of pts, included diarrhea (67%), nausea (67%), vomiting (61%), neutropenia (50%) and decreased appetite (44%). The most common treatment-related grade 3 and 4 toxicities, occurring in 2 or more pts, were neutropenia (64%), leukopenia (29%), AST increased (14%) and febrile neutropenia (14%). PK results will be included in the final abstract. Dinaciclib monotherapy showed some anti-tumor activity, with acceptable safety and tolerability, in patients with ER+/Her2- BC, warranting further exploration in the combination setting. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4718. doi:10.1158/1538-7445.AM2011-4718

9505 Background: AP23573 is an mTOR inhibitor that has shown anti-tumor activity in phase 1 clinical trials, particularly in patients with advanced sarcomas. Given this observation, this phase 2 trial was undertaken to assess further the efficacy and safety of AP23573 across various sarcoma subtypes. Methods: Advanced sarcoma pts, with no restrictions on prior therapies, were enrolled into 4 cohorts based on histologic subtype, in a phase 2 trial with Simon’s 2-stage design. AP23573 (12.5 mg, i.v.) is administered for 5 days every 2 wks. Efficacy is assessed using RECIST guidelines, with clinical benefit response (CBR) defined as complete or partial response (PR) or stable disease (SD) for at least 16 wks duration. For each cohort, treatment was defined as successful if the proportion of patients with CBR was ≥ 25%. Studies of potential predictive markers of response include 18FDG-PET imaging, analysis of mTOR pathway proteins in tumoral tissue, and measurement of plasma cytokines and angiogenic factors. Results: In total, 216 pts were enrolled as all cohorts met criteria to enter Stage 2 of the trial. Of these pts, 213 were treated (106 M/107 F) (age 17–79 yrs, median 50 yrs). Most frequent related adverse events included mucositis, rash, hyperlipidemia, fatigue, and thrombocytopenia. Preliminary response data for 193 evaluable pts are available: overall 54 (28%) had CBRs, including 5 PRs (3 pts with osteo, 1 with spindle cell of bone, and 1 with MFH). Twenty of 76 pts (26%) imaged with PET had rapid induction of partial metabolic responses following 3 to 5 days of study treatment. Conclusions: Initial assessments from this trial show that single-agent AP23573 is well tolerated and has efficacy in pts with advanced sarcomas that warrants evaluation in phase 3. Analysis of the potential utility of FDG-PET and a broad set of candidate biomarkers continues. Enrollment is complete, and pt treatment and follow-up are ongoing. [Table: see text] [Table: see text]

9068 Background: AP23573 (AP) is a non-produg rapamycin analog, which potently inhibits mTOR, a downstream effector of the PI3K/Akt pathway. AP has demonstrated some anti-tumor activity in sarcomas...

9028 Background: AP23573 (AP) is a non-prodrug rapamycin analog, which potently inhibits mTOR, a downstream effector of the PI3K/Akt pathway. AP has demonstrated some anti-tumor efficacy in sarcoma...

TPS10577 Background: Ontuxizumab is a humanized immunoglobulin G-1-kappa monoclonal antibody (mAb) that is the first clinical stage agent to target endosialin. Endosialin (TEM-1/CD248) is a cell su...