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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 Cancer immunotherapies have been very successful in recent times; however, they benefit only a subset of patients and have varying response rates across tumor types. Conversely, conventional chemotherapies are effective in a large group of patients, but have limited dosing capabilities, lack specificity, and often result in systemic adverse events. Here, we present SQ3370, a novel approach that activates doxorubicin (Dox) at the tumor site while avoiding systemic toxicities commonly associated with the therapy, and also potentially activates an immune response against tumors. SQ3370 is based on a local intratumoral injection of a prodrug-capturing biomaterial (SQL70) followed by 5 daily systemic infusions of an attenuated form of Dox (SQP33). Mutually-reactive click chemistry groups in the 2 components allow the capture and release of active Dox at the tumor site. While conventional Dox is known to induce immune activation1 and enhance tumor responsiveness to checkpoint inhibitors,2 its benefit is limited by cumulative dose cardiotoxicity. We safely administered SQ3370 in dogs at 8.95-times the veterinary clinical dose of Dox with minimal side effects including cardiotoxicity and immunosuppression. In syngeneic mouse models, SQ3370 improved overall survival and induced a robust anti-tumor response against the biomaterial-injected lesion compared to conventional Dox. Surprisingly, SQ3370 also induced regression of the non-injected tumor and enhanced T-cell infiltration in both injected and noninjected tumors. We hypothesize that activating Dox at a local site with SQ3370 promotes activation of the native immune system against the tumor. Thus, SQ3370 represents a new therapeutic modality to treat solid tumors by using a drug with known efficacy, Dox, and expanding its therapeutic window. SQ3370 could potentially also benefit patients with widely disseminated or micro-metastatic lesions. Methods SQ3370-001 (NCT04106492), the first-in-human Phase 1 study, is currently open in the United States and Australia to treat patients with advanced solid tumors. SQ3370-001 is enrolling patients ≥ 18 years of age with an injectable local or metastatic lesion, for which published data indicates responsiveness to anthracyclines. Patients must be relapsed or refractory following standard of care therapy and must not have received more than 225 mg/m2 of Dox (or equivalent anthracycline). Each cycle will be for 21 days with no limit on total cycles. Primary objectives include determining the safety, tolerability, and recommended Phase 2 dose. Additional objectives include assessment of the pharmacokinetic profile, preliminary efficacy per RECIST 1.1, and immune response. Results N/A Conclusions N/A Acknowledgements The authors would like to thank the National Institutes of Health (NIH), the National Science Foundation (NSF), and Y Combinator. Ethics Approval This study was approved by:1. The Institutional Review Board (IRB) of Stanford University; eProtocol Number: 54928.2. The IRB of The University of Texas MD Anderson Cancer Center; IRB ID Number: 2020-0185_MOD001.3. Western IRB, on behalf of The Angeles Clinic and Research Institute and Henry Ford Health System IRB Office; IRB Tracking Number: 20200758.4. Bellberry Limited Human Research Ethics Committee, on behalf of Royal North Shore Hospital and Chris O’Brien Lifehouse; Application Number: 2019-10-848. References Mattarollo SR, Loi S, Duret H, Ma Y, Zitvogel L, Smyth MJ. Pivotal role of innate and adaptive immunity in anthracycline chemotherapy of established tumors. Cancer Res 2011;71:4809–4820. Zitvogel L, Galluzzi L, Smyth MJ, Kroemer G. Mechanism of action of conventional and targeted anticancer therapies: reinstating immunosurveillance. Immunity 2013;39:74–88.

Preclinical data suggest that a “prime-boost” vaccine regimen using a target-expressing lentiviral vector for priming, followed by a recombinant protein boost, may be effective against cancer; however, this strategy has not been evaluated in a clinical setting. CMB305 is a prime-boost vaccine designed to induce a broad anti-NY-ESO-1 immune response. It is composed of LV305, which is an NY-ESO-1 expressing lentiviral vector, and G305, a recombinant adjuvanted NY-ESO-1 protein. This multicenter phase 1b, first-in-human trial evaluated CMB305 in patients with NY-ESO-1 expressing solid tumors. Safety was examined in a 3 + 3 dose-escalation design, followed by an expansion with CMB305 alone or in a combination with either oral metronomic cyclophosphamide or intratumoral injections of a toll-like receptor agonist (glucopyranosyl lipid A). Of the 79 patients who enrolled, 81.0% had sarcomas, 86.1% had metastatic disease, and 57.0% had progressive disease at study entry. The most common adverse events were fatigue (34.2%), nausea (26.6%), and injection-site pain (24.1%). In patients with soft tissue sarcomas, a disease control rate of 61.9% and an overall survival of 26.2 months (95% CI, 22.1–NA) were observed. CMB305 induced anti-NY-ESO-1 antibody and T-cell responses in 62.9% and 47.4% of patients, respectively. This is the first trial to test a prime-boost vaccine regimen in patients with advanced cancer. This approach is feasible, can be delivered safely, and with evidence of immune response as well as suggestion of clinical benefit.

Purpose DFP-10917 is a novel deoxycytidine analog with a unique mechanism of action. Brief exposure to high concentrations of DFP-10917 inhibits DNA polymerase resulting in S-phase arrest, while prolonged exposure to DFP-10917 at low concentration causes DNA fragmentation, G2/M-phase arrest, and apoptosis. DFP-10917 demonstrated activity in tumor xenografts resistant to other deoxycytidine analogs. Experimental design Two phase I studies assessed the safety, pharmacokinetic, pharmacodynamic and preliminary efficacy of DFP-10917. Patients with refractory solid tumors received DFP-10917 continuous infusion 14-day on/7-day off and 7-day on/7-day off. Enrollment required age > 18 years, ECOG Performance Status 0–2 and adequate organ function. Results 29 patients were dosed in both studies. In 14-day infusion, dose-limiting toxicities (DLT) consisting of febrile neutropenia and thrombocytopenia occurred at 4.0 mg/m2/day. At 3.0 mg/m2/day, 3 patients experienced neutropenia in cycle 2. The dose of 2.0 mg/m2/day was well tolerated in 6 patients. In 7-day infusion, grade 4 neutropenia was DLT at 4.0 mg/m2/day. The maximum tolerated dose was 3 mg/m2/day. Other toxicities included nausea, vomiting, diarrhea, neutropenia, and alopecia. Eight patients had stable disease for >12 weeks. Paired comet assays performed for 7 patients showed an increase in DNA strand breaks at day 8. Pharmacokinetic data showed dose-proportionality for steady-state concentration and AUC of DFP-10917 and its primary metabolite. Conclusion Continuous infusion of DFP-10917 is feasible and well tolerated with myelosuppression as main DLT. The recommended doses are 2.0 mg/m2/day and 3.0 mg/m2/day on the 14-day and 7-day continuous infusion schedules, respectively. Preliminary activity was suggested. Pharmacodynamic data demonstrate biological activity at the tested doses.

Activating mutations in the genes encoding the tyrosine receptor kinases KIT and platelet-derived growth factor receptor occur in 85%-90% of patients with gastrointestinal stromal tumors (GIST). Although imatinib and other tyrosine kinase inhibitors have revolutionized the treatment of GIST, most patients progress within a few years. Areas covered: Monoclonal antibodies and small-molecule inhibitors targeting specific signaling pathways or proteins associated with resistance to existing treatments are being explored as alternative treatment approaches for GIST. Other alternative approaches include inhibiting more general regulators of protein folding, chromatin packaging, and cell-cycle regulation; nontargeted approaches are also being evaluated in select patient populations. This review summarizes preclinical and clinical data from agents using these accessory pathways. Expert opinion: As we learn more about GIST biology, it is becoming clear that treatment strategies will become more personalized, as reflected by the fact that several trials are enrolling specific subpopulations of patients with GIST. Going forward, researchers should evaluate these new drugs alone or in combination with other types of drugs to better meet patient needs.

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.

Heat shock proteins (Hsp) are highly conserved proteins and their expression is dependent on the level of various cellular stresses. Hsp work as a molecular chaperon for several cellular proteins and have cytoprotective roles. Their function is essential for normal cell viability and growth. Hsp90 interacts with proteins mediating cell signaling involved in essential processes such as proliferation, cell cycle control, angiogenesis and apoptosis. The naturally occurring Hsp90 inhibitor geldanamycin (GA) was the first to demonstrate anticancer activity but its significant toxicity profile in pre-clinical models precluded its clinical development. Subsequent, several Hsp90 inhibitors have been developed and underwent clinical development with favorable safety profiles. Several initial clinical studies have shown promising anticancer activity of Hsp90 inhibitors mainly in breast cancer, non small cell lung carcinoma (NSCLC), gastrointestinal stromal tumors (GIST) and various hematological malignancies. The universal involvement of Hsp90 in multiple oncogenic processes makes Hsp90 inhibitors ideal compounds to be explored as a single agent or in combination with other anticancer therapies.

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.

mTOR was determined to be a promising anticancer target and several drug inhibitors of mTOR are currently in clinical development. Rapamycin (RAP) was the first mTOR inhibitor discovered. However, RAP has poor aqueous solubility and chemical stability and therefore its utilization at doses susceptible to produce an effect as an anticancer agent is limited. This represented the main rationale for developing new RAP analogs. The RAP analogs currently in clinical development as anticancer agents include temsirolimus (CCI-779), everolimus (RAD-001), and deforolimus (AP23573). These agents have demonstrated antiproliferative activity against a diverse range of malignancies in preclinical studies, and clinical evaluations have been very encouraging thus far. Deforolimus (AP23573), a non-RAP prodrug, has been tested in Phase I and II clinical trials and shows promising results in several tumor types including sarcoma. A Phase III study in patients with sarcoma is currently ongoing. The preclinical and clinical studies with deforolimus will be presented.

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.

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.

Nausea and vomiting is one of the most feared side effects of chemotherapy; however, in the past 20 years, a better understanding of the pathophysiology of chemotherapy-induced nausea and vomiting (CINV) has led to the introduction of newer antiemetics, which have improved the management of this side effect.This article reviews the prevention of CINV and the role of aprepitant, the first of the newest class of antiemetics, the neurokinin-1 inhibitors. A brief description of the pathophysiology of CINV and the background on the prevention of CINV using the 5-HT(3) antagonists is outlined. The pharmacology, pharmacokinetics, drug interactions and various clinical studies with aprepitant are reviewed.The literature about aprepitant is reviewed focusing on the role of aprepitant in the management of CINV in relationship to other commonly used antiemetics. The literature was searched regarding aprepitant and its pharmacological characteristics, pharmacokinetics, drug interactions and various clinical studies.Aprepitant has a significant role in the management of CINV, as it allows the majority of patients to complete their chemotherapies without significant morbidity. Its use in a variety of clinical settings in cancer patients needs to be further explored.

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.

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.

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.

Background: Aldoxorubicin is a novel prodrug that covalently binds albumin in the circulation. Doxorubcin is cleaved in low pH environments, allowing administration of 3 1/2 to 4 fold higher doses than standard doxorubicin and 10-fold greater cumulative doses. Patients with metastatic or unresectable soft tissue sarcomas (STS) who have failed prior chemotherapies have a poor prognosis with progresson-free survival (PFS) of around 2-4.5 months and overall survival (OS) of 9-12 months. Several agents have been tested as palliative therapy with these patients including ifosfamide, gemcitabine/docetaxel, dacarbazine and pazopanib. Aldoxorubicin may improve upon the activity of these drugs. Trial design: Phase 3 Open label 400 subjects with intermediate or high grade locally advanced or metastatic STS randomized 1:1 to either aldoxorubicin (A) (350 mg/m2 iv Day 1 every 3 weeks) or investigator's choice (IC) as comparator of any of these treatments: (i) dacarbazine (1000 mg/m2 iv Day 1 every 3 weeks); (ii) pazopanib 800 mg po (iii) gemcitbine (900 mg/m2 iv Days 1 & 8) plus docetaxel (100 mg/m2 iv Day 8) every 3 weeks; (iv) doxorubicin (75 mg/m2 iv Day 1 every 3 weeks); (v) ifosfamide (2 gm/m2 iv Days 1-4 every 3 weeks). The investigative site prespecifies 3 treatment regimens for which CytRx will supply the drugs. Treat to progression or unacceptable toxicity Major inclusions: histological confirmation of tumor type with tissue provided for central review; relapsed/refractory after >/= 1 course of chemotherapy; measurable tumor by RECIST 1.1; ECOG 0-2 Major exclusions:prior exposure to> 375 mg/m2 doxorubicin; inadequate tumor specimen; diagnosis of GIST, alveolar soft part, rhabdo, Ewing's, Kaposi's, osteo, extraskeletal myxoid chondro, dermatofbro, or clear cell sarcomas, or mixed mesodermal tumor; clinically significant cardiac disease, LFTs> 3x (no mets) or 5x (liver mets) normal; ANC Disclosure: S. Wieland: CytRx Employee, Salary and Stock options; D. Levitt: CytRx Employee; Salary and Stock Options. All other authors have declared no conflicts of interest.

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 ...

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...

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...

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.

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.

Background We have studied the safety and tumor response of a doxorubicin conjugate, INNO-206, in patients with metastatic STS who progressed on prior chemotherapy. INNO-206 is a conjugate of doxorubicin attached to an acid-sensitive linker that binds covalently to cysteine-34 in circulating albumin. Methods INNO-206 was administered IV at 350 mg/m2 (260 mg/m2 dox. eq.) every 21 days for up to 8 consecutive cycles. Tumor response was monitored every other month and treatment continued until tumor progression or unacceptable toxicity. Standard safety monitoring was performed and cardiac function was followed periodically using MUGA or cardiac ultrasound. Results As of May 1, 2012, 19 patients were entered in the study. 13/19 patients had STS of various types. Of the initial 19 patients treated at the 350 mg/m2 dose, no individuals experienced a grade 3 or 4 non-hematological toxicity during Cycle 1. The majority of patients demonstrated transient grade 3 or 4 neutropenias that resolved prior to the next cycle with and without G-CSF treatment. No patient exhibited relevant cardiotoxicity as determined by MUGA or cardiac ultrasound. Of 19 patients, serious adverse events included febrile neutropenia (3) sepsis (1) and mucositis (1). Of the 13 patients with STS, 5 objective partial responses (3 of whom received prior doxorubicin) are ongoing as well as 7 patients with stable disease (median 6.43 months, range 1-10.7+ months). 1/13 patients had progressive disease at the first evaluation. 2/19 patients died with the first cycle (1 PD, 1 sepsis). Conclusion INNO-206 is an active drug for the treatment of patients with advanced STS who have failed prior chemotherapy. Cumulative doses of 2000 mg/m2 of doxorubicin equivalents have been achieved, which is over 3½ x the peak cumulative dose of standard doxorubicin. Adverse events are primarily hematological and no cardiotoxicity has been observed. Disclosure S. Chawla: Corporate sponsored research from CytRx Corporation. S. Wieland: Salary and stock ownership from CytRx Corporation. D. Levitt: Salaryand stockownership from CytRx Corporation. All other authors have declared no conflicts of interest.