Lillian L Siu

University Health Network, Toronto, Ontario, Canada

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Publications (308)2308.08 Total impact

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    ABSTRACT: Background: Heat-shock protein 990 (HSP990) is a potent and selective synthetic small-molecule HSP90 inhibitor. The primary objectives of this phase I first-in-human study were to determine dose-limiting toxicities (DLTs), maximum-tolerated dose (MTD) and recommended phase II dose (RP2D). Secondary objectives included characterisation of the safety profile, pharmacokinetics (PKs) and pharmacodynamics (PDs). Methods: Heat-shock protein 990 was administered orally once or two times weekly on a 28-day cycle schedule in patients with advanced solid tumours. Dose escalation was guided by a Bayesian logistic regression model with overdose control. Results: A total of 64 patients were enrolled. Fifty-three patients received HSP990 once weekly at 2.5, 5, 10, 20, 30, 50 or 60 mg, whereas 11 patients received HSP990 two times weekly at 25 mg. Median duration of exposure was 8 weeks (range 1-116 weeks) and 12 patients remained on treatment for >16 weeks. Dose-limiting toxicities occurred in seven patients and included diarrhoea, QTc prolongation, ALT/AST elevations and central neurological toxicities. The most common drug-related adverse events were diarrhoea, fatigue and decreased appetite. Further dose escalation beyond 60 mg once weekly was not possible owing to neurological toxicity. Rapid absorption, no drug accumulation and large interpatient variability in PK exposures were observed. No objective responses were seen; 25 patients had a best overall response of stable disease. Conclusions: Heat-shock protein 990 is relatively well tolerated, with neurological toxicity being the most relevant DLT. The single agent MTD/RP2D of HSP990 was declared at 50 mg once weekly.
    British Journal of Cancer 01/2015; 112(4). DOI:10.1038/bjc.2014.653 · 4.84 Impact Factor
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    ABSTRACT: Background: AT7519 is a small-molecular inhibitor of multiple cyclin-dependent kinases (CDKs). It shows encouraging anti-cancer activity against multiple cell lines and in tumour xenografts. This phase I study was conducted to evaluate the safety and tolerability of AT7519 given as 1-h intravenous infusion on days 1, 4, 8 and 11 every 3 weeks. Methods: Patients with advanced refractory solid tumours or non-Hodgkin's lymphoma were enroled. Dose escalation occurred in a 3+3 manner based on toxicity assessment. Pharmacokinetic samples were collected after first AT7519 infusion, whereas pharmacodynamics (PD) samples were obtained in selected patients. Results: Thirty-four patients were enroled, and 32 received study treatments over 4 dose levels. Dose-limiting toxicities included mucositis, febrile neutropenia, rash, fatigue and hypokalemia. The recommended phase II dose (RP2D) was 27.0 mg m(-2). Ten of 19 patients evaluable for efficacy had stable disease as the best response (median duration: 3.3 months; range: 2.5 to 11.1 months). There was no clinically significant QTc prolongation. There was an apparent dose proportional increase in AT7519 exposure. The PD studies showed reduction in markers of CDK activity in selected patients' skin biopsies post treatment. Conclusions: AT7519, when administered as an intravenous infusion on days 1, 4, 8 and 11, was well tolerated. The RP2D is 27.0 mg m(-2). At this dose level, plasma AT7519 concentrations were above the biologically active concentrations, and preliminary anti-cancer activity was observed in patients. This dosing schedule is being further evaluated in multiple phase II studies.
    British Journal of Cancer 11/2014; 111(12). DOI:10.1038/bjc.2014.565 · 4.84 Impact Factor
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    ABSTRACT: Purpose Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) and fibroblast growth factor-inducible molecule 14 (Fn14) are a ligand-receptor pair frequently overexpressed in solid tumors. TWEAK:Fn14 signaling regulates multiple oncogenic processes through MAPK, AKT, and NFκB pathway activation. A phase I study of RG7212, a humanized anti-TWEAK IgG1κ monoclonal antibody, was conducted in patients with advanced solid tumors expressing Fn14. Methods Dose escalations, over a 200- to 7200-mg range, were performed with patients enrolled in weekly (QW), bi-weekly (Q2W), or every-three-week (Q3W) schedules. Primary objectives included determination of dose and safety profile. Secondary endpoints included assessments related to inhibition of TWEAK:Fn14 signaling, tumor proliferation, tumor immune cell infiltration, and pharmacokinetics. Results In 192 treatment cycles administered to 54 patients, RG7212 was well-tolerated with no dose-limiting toxicities observed. More than 95% of related adverse events were limited to grade 1/2. Pharmacokinetics were dose proportional for all cohorts, with a t1/2 of 11-12 days. Pharmacodynamic changes included clearance of free and total TWEAK ligand and reductions in tumor Ki-67 and TRAF1. A patient with BRAF wild-type melanoma who received 36 weeks of RG7212 therapy had tumor regression and pharmacodynamic changes consistent with antitumor effects. Fifteen patients (28%) received 16 or more weeks of RG7212 treatment.
    Clinical Cancer Research 11/2014; DOI:10.1158/1078-0432.CCR-14-1334 · 8.72 Impact Factor

  • European Journal of Cancer 11/2014; 50:79-80. DOI:10.1016/S0959-8049(14)70363-6 · 5.42 Impact Factor

  • European Journal of Cancer 11/2014; 50:171. DOI:10.1016/S0959-8049(14)70652-5 · 5.42 Impact Factor

  • European Journal of Cancer 11/2014; 50:165-166. DOI:10.1016/S0959-8049(14)70634-3 · 5.42 Impact Factor
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    ABSTRACT: Purpose: The combination of low-dose radiotherapy with PARP inhibition has been shown to enhance antitumor efficacy through potentiating DNA damage. We combined low-dose fractionated whole abdominal radiation (LDFWAR) with escalating doses of veliparib (ABT-888), a small-molecule PARP inhibitor, in patients with peritoneal carcinomatosis from advanced solid tumor malignancies. Experimental design: Patients were treated with veliparib (80-320 mg daily) for a total of 3 cycles. LDFWAR consisted of 21.6 Gy in 36 fractions, 0.6 Gy twice daily on days 1 and 5 for weeks 1-3 of each cycle. Circulating tumor cells (CTC) were collected and evaluated for γ-H2AX. Quality of life (QoL) was assessed using the EORTC-QLQ-C30 questionnaire. Results: Twenty-two patients were treated. Treatment-related grade 3 and 4 toxicities included lymphopenia (68%), anemia (9%), thrombocytopenia (14%), neutropenia (4%), leukopenia (9%), ascites (4%), vomiting (4%), and dyspnea (4%). No objective responses were observed. Disease stabilization (≥24 weeks) was observed in 7 patients (33%). Median progression-free survival (mPFS) was 4.47 months and median overall survival (mOS) was 13.04 months. In the subset of 8 ovarian and fallopian cancers, mPFS was 6.77 months and mOS was 17.54 months compared with mPFS 2.71 months and mOS 13.01 months in others. Patients with ovarian and fallopian cancers had better QoL over time than those with other cancers. An increased percentage of γ-H2AX-positive CTCs was observed in a subset of patients (3/6 with >2 CTCs at baseline). Conclusions: Combined veliparib and LDFWAR is a well-tolerated regimen that resulted in prolonged disease stability for some patients with advanced solid tumors and carcinomatosis, particularly in the ovarian and fallopian cancer subpopulation.
    Clinical Cancer Research 10/2014; 21(1). DOI:10.1158/1078-0432.CCR-14-1552 · 8.72 Impact Factor
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    ABSTRACT: The implementation of cancer genomic testing into the clinical setting has brought major opportunities. However, as our understanding of cancer initiation, maintenance and progression improves through detailed cancer genomic studies, the challenges associated with driver identification and target classification in the clinical setting become clearer. Here, we review recent insights into cancer genomic testing in the clinical setting, and suggest a target classification approach that considers the levels of evidence supporting the prioritization of tumour drivers for therapeutic targeting in light of complex cancer clonal and sub-clonal structures and clinical successes and failures in the field. We argue that such classification approaches, together with transparent reporting of both positive and negative clinical data and continued research to identify the sub-clonal dynamics of driver events during the disease course, will facilitate inter-trial comparisons, optimize patient informed consent and provide a critically balanced evaluation of genomic testing in clinical practice.
    Annals of Oncology 10/2014; 25(12). DOI:10.1093/annonc/mdu478 · 7.04 Impact Factor
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    ABSTRACT: Background: RO4929097 is an oral inhibitor of γ -secretase that results in Notch signaling inhibition. Prior work has demonstrated that Notch signaling inhibition enhances chemotherapy sensitivity of cancer cells. This phase I study was conducted to determine maximum tolerated dose (MTD), toxicities and efficacy of RO4929097 and capecitabine in advanced solid tumors. Methods: Patients with refractory solid tumors received capecitabine at a fixed dose of 1,000 mg/m(2) twice daily with escalating doses of RO4929097 on a 21-day cycle in a 3 + 3 design. Capecitabine was administered for 14 days and the RO49029097 once daily, 3 days per week, both for a 21 day cycle. Results: Thirty patients were treated on six dose levels (20 to 150 mg). The maximally tolerated dose was not reached. One dose limiting toxicity was observed at each level 3 through 6 (hypophosphatemia, fatigue, and nausea/vomiting). Three confirmed partial responses were observed: two patients with fluoropyrimide-refractory colon cancer and one patient with cervical cancer. Autoinduction of RO4929097 was demonstrated with increasing dose levels and duration. Conclusions: The recommended phase 2 dose is capecitabine 1,000 mg/m(2) orally twice daily on days 1 through 14 with RO4929097 20 mg orally once daily on days 1-3, 8-10 and 15-17 with a 21 day cycle. Clinical benefit was observed in cervical and colon cancer. Autoinduction of RO4929097 was seen both with increasing cycle number and increasing dose. Plasma concentrations of RO4929097 were above those needed for Notch inhibition.
    Investigational New Drugs 10/2014; 33(1). DOI:10.1007/s10637-014-0166-6 · 2.92 Impact Factor
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    ABSTRACT: Background: Two strategies to interrogate the insulin growth factor 1 receptor (IGF-1R) pathway were investigated: vertical inhibition with dalotuzumab and MK-2206 or ridaforolimus to potentiate PI3K pathway targeting and horizontal cross-talk inhibition with dalotuzumab and MK-0752 to exert effects against cellular proliferation, angiogenesis, and stem cell propagation. Methods: A phase I, multi-cohort dose escalation study was conducted in patients with advanced solid tumours. Patients received dalotuzumab (10 mg kg(-1)) and escalating doses of MK-2206 (90-200 mg) or escalating doses of dalotuzumab (7.5-10 mg kg(-1)) and MK-0752 (1800 mg) weekly. Upon maximum tolerated dose determination, patients with low-RAS signature, high-IGF1 expression ovarian cancer were randomised to dalotuzumab/MK-2206 versus dalotuzumab/ridaforolimus, whereas patients with high IGF1/low IGF2 expression colorectal cancer received dalotuzumab/MK-0752. Results: A total of 47 patients were enrolled: 29 in part A (18 in the dalotuzumab/MK-2206 arm and 11 in the dalotuzumab/MK-0752 arm) and 18 in part B (6 in each arm). Dose-limiting toxicities (DLTs) for dalotuzumab/MK-2206 included grade 4 neutropenia and grade 3 serum sickness-like reaction, maculopapular rash, and gastrointestinal inflammation. For dalotuzumab/MK-0752, DLTs included grade 3 dehydration, rash, and diarrhoea. Seven patients remained on study for >4 cycles. Conclusions: Dalotuzumab/MK-2206 and dalotuzumab/MK-0752 combinations were tolerable. Further developments of prospectively validated predictive biomarkers to aid in patient selection for anti-IGF-1R therapies are needed.
    British Journal of Cancer 10/2014; 111(10). DOI:10.1038/bjc.2014.497 · 4.84 Impact Factor
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    ABSTRACT: Background: Genomic testing in cancer (GTC) characterizes genes that play an important role in the development and growth of a patient's cancer. This form of DNA testing is currently being studied for its ability to guide cancer therapy. The objective of the current study was to describe patients' knowledge, attitudes, and expectations toward GTC. Methods: A 42-item self-administered GTC questionnaire was developed by a multidisciplinary group and patient pretesting. The questionnaire was distributed to patients with advanced cancer who were referred to the Princess Margaret Cancer Center for a phase 1 clinical trial or GTC testing. Results: Results were reported from 98 patients with advanced cancer, representing 66% of the patients surveyed. Seventy-six percent of patients were interested in learning more about GTC, and 64% reported that GTC would significantly improve their cancer care. The median score on a 12-item questionnaire to assess knowledge of cancer genomics was 8 of 12 items correct (67%; interquartile range, 7-9 of 12 items correct [58%-75%]). Scores were associated significantly with patients' education level (P < .0001). Sixty-six percent of patients would consent to a needle biopsy, and 39% would consent to an invasive surgical biopsy if required for GTC. Only 48% of patients reported having sufficient knowledge to make an informed decision to pursue GTC whereas 34% of patients indicated a need for formal genetic counseling. Conclusions: Patients with advanced cancer are motivated to participate in GTC. Patients require further education to understand the difference between somatic and germline mutations in the context of GTC. Educational programs are needed to support patients interested in pursuing GTC.
    Cancer 10/2014; 120(19). DOI:10.1002/cncr.28807 · 4.89 Impact Factor

  • Cancer Research 10/2014; 74(19 Supplement):3121-3121. DOI:10.1158/1538-7445.AM2014-3121 · 9.33 Impact Factor
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    ABSTRACT: Background: In preclinical models, the proton pump inhibitor pantoprazole enhances the antitumor activity of chemotherapeutic agents by improving drug distribution and by inhibiting autophagy. Methods: Patients with advanced solid tumors (n = 24) received doxorubicin 60 mg/m(2) and escalating doses of pantoprazole (80, 160, 240 and 360 mg) administered intravenously prior to doxorubicin. Blood samples were collected for pharmacokinetic studies. An optional biopsy was performed to evaluate doxorubicin concentration and pharmacodynamic markers of drug activity. Results: Twenty-four patients participated in the study (17 in the dose escalation phase and 7 in the dose expansion). Three patients experienced a dose limiting toxicity (grade 3 fatigue in the three cases), one patient at dose level 3 (pantoprazole 240 mg) and two patients at dose level 4 (pantoprazole 360 mg). Dose level 4 was considered to exceed the maximum tolerated dose. The recommended phase II dose was pantoprazole 240 mg and doxorubicin 60 mg/m(2). The most commonly observed toxicities included fatigue, neutropenia and leukopenia. Two patients achieved a confirmed partial response. Median maximum serum concentration of pantoprazole was 84.3 μM at 1-2 h after injection of pantoprazole 240 mg. No drug-drug interaction was observed. A single on-treatment tumor biopsy showed a sharply decreasing gradient in doxorubicin concentration and associated activity markers with increasing distance from tumor blood vessels. Conclusion: Administration of high doses of pantoprazole in combination with doxorubicin is feasible. The recommended phase II dose of pantoprazole, 240 mg, will be evaluated in combination with docetaxel as first line in patients with castration-resistant prostate cancer.
    Investigational New Drugs 09/2014; 32(6). DOI:10.1007/s10637-014-0159-5 · 2.92 Impact Factor
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    ABSTRACT: The purpose of early stage clinical trials is to determine the recommended dose and toxicity profile of an investigational agent or multi-drug combination. Molecularly targeted agents (MTAs) and immunotherapies have distinct toxicities from chemotherapies that are often not dose dependent and can lead to chronic and sometimes unpredictable side effects. Therefore utilizing a dose escalation method that has toxicity based endpoints may not be as appropriate for determination of recommended dose, and alternative parameters such as pharmacokinetic or pharmacodynamic outcomes are potentially appealing options. Approaches to enhance safety and optimize dosing include improved preclinical models and assessment, innovative model based design and dose escalation strategies, patient selection, the use of expansion cohorts and extended toxicity assessments. Tailoring the design of phase I trials by adopting new strategies to address the different properties of MTAs is required to enhance the development of these agents. This review will focus on the limitations to safety and dose determination that have occurred in the development of MTAs and immunotherapies. In addition, strategies are proposed to overcome these challenges to develop phase I trials that can more accurately define the recommended dose and identify adverse events.
    Molecular Oncology 08/2014; DOI:10.1016/j.molonc.2014.07.025 · 5.33 Impact Factor
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    ABSTRACT: Could the human papillomavirus (HPV) vaccination be cost-effective in males for the prevention of oropharyngeal squamous cell cancer (OPC)? It could be under certain conditions. Research on HPV vaccine has focused mainly on females. However, within the next decade, it is predicted that OPC will surpass cervical cancer as the most common HPV-related cancer, and it is postulated that HPV vaccination may alter the incidence of OPC. The purpose of this editorial is to comment on the potential cost-effectiveness of HPV vaccination in males for OPC prevention by addressing three elements payers often consider when making a decision to fund an intervention and to provide an overview of recent findings regarding the cost-effectiveness of HPV vaccine in males.
    Expert Review of Pharmacoeconomics & Outcomes Research 08/2014; 14(6):1-3. DOI:10.1586/14737167.2014.946012 · 1.67 Impact Factor
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    ABSTRACT: Introduction It is increasingly clear that definitions of dose-limiting toxicity (DLT) established for phase 1 trials of cytotoxic agents are not suitable for molecularly targeted agents because of specific toxicity profiles. An international survey collected expertise on the definition of DLT, as part of an initiative aimed at presenting new guidelines for phase 1 trials of targeted agents. Methods A 15-question survey was sent to corresponding authors of phase 1 reports. Questions involved: duration of the DLT assessment period, incorporation of specific grade 1 (G1) or G2 toxicity and their minimum duration to qualify as DLT, exclusion of specific G3 and inclusion of dose modification/delay. Results Among the 400 investigators contacted, 93 replied of whom 65 completed the questionnaires. A total of 87% opted for an extended DLT assessment period beyond cycle 1, with the proviso not to delay patient accrual. Reanalysis at the end of the study of all safety data was proposed in order to recommend the phase 2 dose. Most respondents (92%) suggested including dose modification in the definition of DLT when dose intensity was decreased to 70%. Whilst moderate toxicity was deemed relevant by 70%, the G1/2 toxicities selected to define DLT however varied. Conclusion The majority of experts favoured a longer DLT assessment period as well as incorporation of specific G2 toxicities into the DLT definition. However, no clear consensus existed on a re-definition of DLT. Therefore analyses of a large international data warehouse were also used to develop guidelines presented in a companion paper.
    European Journal of Cancer 08/2014; 50(12). DOI:10.1016/j.ejca.2014.04.030 · 5.42 Impact Factor
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    Aaron R Hansen · Donna M Graham · Gregory R Pond · Lillian L Siu ·
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    ABSTRACT: Background: Concerns have been recognized about the operating characteristics of the standard 3 + 3 dose-escalation design. Various innovative phase 1 trial designs have been proposed to address the issues and new challenges posed by molecularly targeted agents. However, in spite of these proposals, the conventional design is still the most widely utilized. Methods: A review of the literature of phase 1 trials and relevant statistical studies was performed. Results: Beyond statistical simulations, sparse clinical data exist to support or refute many of the shortcomings ascribed to the 3 + 3 rule method. Data from phase 1 trials demonstrate that traditional designs identified the correct dose and relevant toxicities with an acceptable level of precision in some instances; however, no single escalation method was proven superior in all circumstances. Conclusions: Design selection should be guided by the principle of slow escalation in the face of toxicity and rapid dose increases in the setting of minimal or no adverse events. When the toxicity of a drug is uncertain or a narrow therapeutic window is suggested from preclinical testing, then a conservative 3 + 3 method is generally appropriate. However, if the therapeutic window is wide and the expected toxicity is low, then rapid escalation with a novel rule- or model-based design should be employed.
    Cancer control: journal of the Moffitt Cancer Center 07/2014; 21(3):200-208. · 3.50 Impact Factor
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    ABSTRACT: Background: Induction chemotherapy followed by concurrent chemoradiation (CRT) (sequential therapy) has been evaluated in the treatment of locoregionally-advanced squamous cell cancer of the head and neck (LA-SCCHN), with docetaxel, cisplatin (P) and 5-flurouracil (F) shown to be superior to PF doublet. Nab-paclitaxel (A) is a novel albumin-bound paclitaxel with a superior therapeutic index to docetaxel. Methods: A phase I trial [Clinical identifier NCT00731380] to assess the safety and efficacy of nab-paclitaxel+cisplatin+5-fluorouracil (APF) as induction chemotherapy for three cycles, followed by concurrent carboplatin (area-under-curve (AUC) 1.5 weekly) with radiation therapy (RT) (70 Gy/35 fractions), was conducted using a 3+3 design in patients with previously untreated LA-SCCHN. Dose-limiting toxicities (DLTs) included: standard haematologic and non-haematologic toxicities, treatment delays, inability to complete ⩾95% of RT and skin/mucosal toxicity related to RT assessed from day 1 of treatment to 8 weeks after completion of CRT. Results: 17 patients with oropharyngeal cancer were enrolled in three dose levels, with 15 patients evaluable for DLT. The median age was 54 years (range, 44-65 years), 14 patients were male, and 11 patients' tumours were p16 positive and four negative. Grade 3/4 adverse events during APF (%total number of cycles) were hyponatraemia (14%) neutropenia (10%), lymphopaenia (4%) and thrombocytopenia (2%) during 49 evaluable APF cycles. Febrile neutropenia occurred during one cycle of treatment. Conclusion: The recommended phase 2 dose of APF is nab-paclitaxel 100mg/m(2) days 1 and 8, cisplatin 75 mg/mg(2) day 1 and 5-fluorouracil 1000 mg/m(2)/day×96 h days 1-4, every 3 weeks, for three cycles prior to CRT.
    European journal of cancer (Oxford, England: 1990) 06/2014; 50(13). DOI:10.1016/j.ejca.2014.05.021 · 5.42 Impact Factor
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    ABSTRACT: Introduction: Traditional dose-limiting toxicity (DLT) definition, which uses grade (G) 3-4 toxicity data from cycle 1 (C1) only, may not be appropriate for molecularly targeted agents (MTAs) of prolonged administration, for which late or lower grade toxicities also deserve attention. Patients and methods: In collaboration with pharmaceutical companies and academia, an European Organisation for Research and Treatment of Cancer (EORTC)-led initiative, Dose-Limiting Toxicity and Toxicity Assessment Recommendation Group for Early Trials of Targeted therapies (DLT-TARGETT), collected data from completed phase 1 trials evaluating MTAs as monotherapy. All toxicities at least possibly related to the study drugs that occurred during C1-6, their type, grade (CTCAEv3.0), and duration as well as patients' relative dose-intensity (RDI), were recorded. Results: The 54 eligible trials enrolled 2084 evaluable adult patients with solid tumours between 1999 and 2013, and evaluated small molecules (40), antibodies (seven), recombinant peptides (five) and antisense oligodeoxynucleotides (two). A maximum tolerated dose was set in 43 trials. Fifteen percent of the patients received <75% of the intended RDI in C1, but only 9.1% of them presented protocol-defined DLTs. After C1, 16-19% of patients received <75% of the intended RDI. A similar proportion of G ⩾ 3 toxicities was recorded in C1 and after C1 (936 and 1087 toxicities, respectively), with the first G⩾3 toxicity occurring after C1 in 18.6% of patients. Conclusion: Although protocol-defined DLT period is traditionally limited to C1, almost 20% of patients present significant reductions in RDI at any time in phase 1 trials of MTAs. Recommended phase 2 dose assessment should incorporate all available information from any cycle (notably lower grade toxicities leading to such RDI decrease), and be based on achieving >75% RDI.
    European journal of cancer (Oxford, England: 1990) 05/2014; 50(12). DOI:10.1016/j.ejca.2014.04.031 · 5.42 Impact Factor
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    ABSTRACT: Epidermal growth factor receptor (EGFR) is over-expressed in nearly all cases of squamous cell carcinoma of the head and neck (SCCHN), and is an important driver of disease progression. EGFR targeted therapies have demonstrated clinical benefit for SCCHN treatment. In this report, we investigated the pre-clinical efficacy of Dacomitinib (PF-00299804), an irreversible pan-ErbB inhibitor, both alone and in combination with ionizing radiation (IR), a primary curative modality for SCCHN. One normal oral epithelial (NOE) and three SCCHN (FaDu, UT-SCC-8, UT-SCC-42a) cell lines were used to conduct cell viability, clonogenic survival, cell cycle, and immunoblotting assays in vitro, using increasing doses of Dacomitinib (10-500 nM), both with and without IR (2-4 Gy). The FaDu xenograft model was utilized for tumor growth delay assays in vivo, and immunohistochemical analyses were conducted on extracted tumors. A dose-dependent reduction in cell viability and clonogenic survival after Dacomitinib treatment was observed in all three SCCHN models. Treatment led to a significant reduction in EGFR signalling, with a subsequent decrease in phosphorylation of downstream targets such as ERK, AKT, and mTOR. In vivo, Dacomitinib treatment delayed tumor growth, while decreasing phospho-EGFR and Ki-67 immunoexpression. These effects were further enhanced when combined with IR, both in vitro and in vivo. The preclinical data support the further evaluations of Dacomitinib combined with IR for the future management of patients with SCCHN.
    PLoS ONE 05/2014; 9(5):e98557. DOI:10.1371/journal.pone.0098557 · 3.23 Impact Factor

Publication Stats

10k Citations
2,308.08 Total Impact Points


  • 2002-2015
    • University Health Network
      • • Princess Margaret Hospital
      • • Department of Medical Oncology
      Toronto, Ontario, Canada
    • Centre hospitalier de l'Université de Montréal (CHUM)
      Montréal, Quebec, Canada
  • 1998-2015
    • University of Toronto
      • • Department of Medicine
      • • Department of Radiation Oncology
      Toronto, Ontario, Canada
    • The Princess Margaret Hospital
      Toronto, Ontario, Canada
  • 2009
    • University of Texas MD Anderson Cancer Center
      • Department of Biostatistics
      Houston, Texas, United States
  • 2008
    • Memorial Sloan-Kettering Cancer Center
      New York, New York, United States
  • 2007
    • University of Chicago
      Chicago, Illinois, United States
  • 2006
    • National Cancer Institute (USA)
      베서스다, Maryland, United States
    • Hôpital Maisonneuve-Rosemont
      Montréal, Quebec, Canada
  • 2001
    • BC Cancer Agency
      Vancouver, British Columbia, Canada
    • University of Texas Health Science Center at San Antonio
      • Department of Medicine
      San Antonio, Texas, United States