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PDF file - 182K, Tumor reduction in 3 patients who achieved a partial response following (A) 21 days, (B) 15 months, and (C) 18 months of treatment

Supplementary Methods; Supplementary Table S1.

Purpose: Increased mitogenic signaling and angiogenesis, frequently facilitated by somatic activation of EGF receptor (EGFR; ErbB1) and/or loss of PTEN, and VEGF overexpression, respectively, drive malignant glioma growth. We hypothesized that patients with recurrent glioblastoma would exhibit differential antitumor benefit based on tumor PTEN/EGFRvIII status when treated with the antiangiogenic agent pazopanib and the ErbB inhibitor lapatinib.Experimental Design: A phase II study evaluated the antitumor activity of pazopanib 400 mg/d plus lapatinib 1,000 mg/d in patients with grade 4 malignant glioma and known PTEN/EGFRvIII status not receiving enzyme-inducing anticonvulsants (EIAC). The phase II study used a two-stage Green–Dahlberg design for futility. An independent, parallel phase I component determined the maximum-tolerated regimen (MTR) of pazopanib and lapatinib in patients with grade 3/4 glioma receiving EIACs.Results: The six-month progression-free survival (PFS) rates in phase II (n = 41) were 0% and 15% in the PTEN/EGFRvIII-positive and PTEN/EGFRvIII-negative cohorts, respectively, leading to early termination. Two patients (5%) had a partial response and 14 patients (34%) had stable disease lasting 8 or more weeks. In phase I (n = 34), the MTR was not reached. On the basis of pharmacokinetic and safety review, a regimen of pazopanib 600 mg plus lapatinib 1,000 mg, each twice daily, was considered safe. Concomitant EIACs reduced exposure to pazopanib and lapatinib.Conclusions: The antitumor activity of this combination at the phase II dose tested was limited. Pharmacokinetic data indicated that exposure to lapatinib was subtherapeutic in the phase II evaluation. Evaluation of intratumoral drug delivery and activity may be essential for hypothesis-testing trials with targeted agents in malignant glioma. Clin Cancer Res; 19(4); 900–8. ©2012 AACR.

PDF file - 179K, Study design

Purpose: GSK461364 is an ATP-competitive inhibitor of polo-like kinase 1 (Plk1). A phase I study of two schedules of intravenous GSK461364 was conducted.Experimental Design: GSK461364 was administered in escalating doses to patients with solid malignancies by two schedules, either on days 1, 8, and 15 of 28-day cycles (schedule A) or on days 1, 2, 8, 9, 15, and 16 of 28-day cycles (schedule B). Assessments included pharmacokinetic and pharmacodynamic profiles, as well as marker expression studies in pretreatment tumor biopsies.Results: Forty patients received GSK461364: 23 patients in schedule A and 17 in schedule B. Dose-limiting toxicities (DLT) in schedule A at 300 mg (2 of 7 patients) and 225 mg (1 of 8 patients) cohorts included grade 4 neutropenia and/or grade 3–4 thrombocytopenia. In schedule B, DLTs of grade 4 pulmonary emboli and grade 4 neutropenia occurred at 7 or more days at 100 mg dose level. Venous thrombotic emboli (VTE) and myelosuppression were the most common grade 3–4, drug-related events. Pharmacokinetic data indicated that AUC (area under the curve) and Cmax (maximum concentration) were proportional across doses, with a half-life of 9 to 13 hours. Pharmacodynamic studies in circulating tumor cells revealed an increase in phosphorylated histone H3 (pHH3) following drug administration. A best response of prolonged stable disease of more than 16 weeks occurred in 6 (15%) patients, including 4 esophageal cancer patients. Those with prolonged stable disease had greater expression of Ki-67, pHH3, and Plk1 in archived tumor biopsies.Conclusions: The final recommended phase II dose for GSK461364 was 225 mg administered intravenously in schedule A. Because of the high incidence (20%) of VTE, for further clinical evaluation, GSK461364 should involve coadministration of prophylactic anticoagulation. Clin Cancer Res; 17(10); 3420–30. ©2011 AACR.

TPS3165 Background: ImmTAC bispecifics are unique T cell receptor (TCR)/anti-CD3 bispecific molecules that are designed to redirect polyclonal T cells against intracellular antigens, in contrast to antibody-based therapies, which are limited to extracellular antigens. ImmTAC molecules recognize a specific peptide presented on defined Class I HLA molecules via an affinity enhanced, engineered, soluble TCR. Through the addition of an anti-CD3 scFv effector domain fused to the TCR targeting domain, ImmTAC molecules redirect T cell activity against cancer cells, regardless of the specificity of the T cell. IMC-C103C is an ImmTAC being investigated against MAGE-A4, which is among the most commonly expressed cancer testis antigens in solid malignancies, but with minimal to absent expression on normal tissues and/or hematopoietic cells. The most advanced ImmTAC in development, tebentafusp (IMCgp100), directed against melanocyte-associated lineage antigen gp100, has shown monotherapy activity in uveal melanoma and PD-1 refractory advanced cutaneous and uveal melanoma. Tebentafusp is being further evaluated in combination with durvalumab and tremelimumab. Methods: IMC-C103C-101 is a multi-center, open-label, Phase 1/2 first-in-human study of IMC-C103C as monotherapy and combination with atezolizumab in HLA-A*02:01-positive patients with MAGE-A4-positive advanced cancers. The study includes IMC-C103C monotherapy (Q1W) dose escalation, followed by expansion into indication specific arms to test for efficacy in defined patient cohorts. Concurrently, combinations with atezolizumab are planned. Primary objectives of dose escalation are to identify the MTD/RP2D, and characterize safety/tolerability. Secondary objectives include an assessment of efficacy (best overall response by RECIST v1.1), PK, PD, and ADA. IMC-C103C monotherapy dose escalation is in progress. Clinical trial information: NCT03973333 .

Introduction Platinum doublet chemotherapy has represented the standard of care in advanced non–small-cell lung cancer for decades. Targeting platelet-derived growth factor receptors (PDGFR) is a potential mechanism to improve the efficacy of first-line therapy. This randomized phase 1b/2 trial investigated the addition of the anti-PDGFRα monoclonal antibody MEDI-575 to first-line carboplatin/paclitaxel (CP) chemotherapy. Patients and Methods The phase 1b component was a dose-escalation study combining MEDI-575 with carboplatin area under the plasma concentration versus time curve 6 and paclitaxel 200 mg/m2 (CPM), with the end point of identifying a recommended phase 2 dose. The phase 2 component randomized patients to CPM or CP, with primary end point of progression-free survival. Secondary end points included overall survival, overall response rate, and adverse event rates. Results Overall, 99 patients were enrolled and received either CPM (n = 53; 4 phase 1b, 49 phase 2) or CP (n = 46). Demographics were as follows: 63/36 male/female, 78/21 aged ≤ 70/> 70 years; 37/62 squamous/nonsquamous, 42/53 Eastern Cooperative Oncology Group performance status 0/1. The phase 2 portion of the trial did not meet its primary end point: progression-free survival was shorter with CPM (4.6 vs. 5.5 months) than CP. No significant difference was seen in overall response rate (31.7% vs. 22.5%) or median overall survival (10.0 vs. 11.8 months). More serious adverse events were observed in patients receiving CPM (47% vs. 40%); in particular, 9 patients in the CPM group had significant gastrointestinal or respiratory adverse events (including abscess, perforation, and pneumothorax). Conclusion The addition of MEDI-575 to CP chemotherapy as first-line treatment of advanced non–small-cell lung cancer did not improve efficacy and resulted in increased toxicity.

The potential for an interaction between lapatinib and absorption of the P-glycoprotein (ABCB1) substrate digoxin at a therapeutic dose in breast cancer patients was characterized. Seventeen women with HER2-positive metastatic breast cancer received a single oral 0.5-mg dose of digoxin on days 1 and 9 and oral lapatinib 1500 mg once daily on days 2 through 9. Digoxin pharmacokinetic parameters were determined on day 1 (digoxin administration alone) and on day 9 (coadministration of lapatinib and digoxin), and parameters were compared to determine the effects of lapatinib on digoxin absorption. Concomitant medications that could affect ABCB1 were accounted for. Lapatinib 1500 mg/day increased digoxin absorption approximately 80%, implicating lapatinib inhibition of intestinal ABCB1-mediated efflux. In summary, coadministration of lapatinib with narrow therapeutic index drugs that are substrates of ABCB1 should be undertaken with caution and dose adjustment should be considered.

Aims The aim of the study was to determine the effect of renal impairment and prior platinum-based chemotherapy on the toxicity and pharmacokinetics of oral topotecan and to identify recommended doses for patients with renal impairment or prior platinum-based (PB) chemotherapy. Methods A multicentre phase I toxicity and pharmacokinetic study of oral topotecan was conducted in patients with advanced solid tumours. Patients were grouped by normal renal function with limited or prior PB chemotherapy or impaired renal function (mild [creatinine clearance (CLcr)=50-79 ml min-1], moderate [CLcr=30-49 ml min-1], severe [CLcr -1]). Results Fifty-nine patients were evaluable. Topotecan lactone and total topotecan area under the concentration-time curve (AUC) was significantly increased in patients with moderate and severe renal impairment (109% and 174%, respectively, topotecan lactone and 148% and 298%, respectively, total topotecan). Asian patients (23 in total) had higher AUCs than non-Asian patients with the same degree of renal impairment. Thirteen dose-limiting toxicities (DLTs) were observed, which were mostly haematological. The maximum tolerated dose (MTD) was 2.3 mg m-2 day-1, given on days 1 to 5 in a 21 day cycle, for patients with prior PB chemotherapy or mild renal impairment, and 1.2 mg m-2 day-1 for patients with moderate renal impairment (suggested dose 1.9 mg m-2 day-1 for non-Asians). Due to incomplete enrolment of patients with severe renal impairment, the MTD was determined as ≥ 0.6 mg m-2 day-1 in this cohort. Conclusions Oral topotecan dose adjustments are not required in patients with prior PB chemotherapy or mildly impaired renal function, but reduced doses are required for patients with moderate or severe renal impairment.

Purpose: This first-in-human study aimed to determine the MTD and safety of MEDI3617, a selective anti–angiopoietin-2 (Ang2) mAb, alone and combined with bevacizumab or cytotoxic chemotherapy. Patients and Methods: This phase I/Ib, multicenter, open-label, dose-escalation and dose-expansion study evaluated patients with advanced solid tumors. Patients received intravenous MEDI3617 as monotherapy [5–1,500 mg every 3 weeks (Q3W)] or with bevacizumab every 2 weeks (Q2W) or Q3W, weekly paclitaxel, or carboplatin plus paclitaxel Q3W. Dose expansions included a monotherapy cohort in platinum-resistant ovarian cancer and a bevacizumab combination cohort in bevacizumab-refractory malignant glioma. Safety/tolerability, pharmacokinetics, pharmacodynamics, and clinical activity were assessed. Results: We enrolled 116 patients. No formal MTD was identified (monotherapy or combination therapy). MEDI3617 demonstrated linear pharmacokinetics and maximal accumulation of peripheral Ang2 binding at doses above 300 mg Q3W. MEDI3617 monotherapy safety profile was acceptable, except in advanced ovarian cancer [prolonged grade 3 edema-associated adverse events (AE) occurred]. Otherwise, MEDI3617 combined with chemotherapy or bevacizumab was well tolerated. The AE profiles of MEDI3617 and bevacizumab were largely non-overlapping. Overall response rates in ovarian cancer and glioma monotherapy dose-expansion arms were 6% and 0%, respectively. Conclusions: Recommended MEDI3617 monotherapy dosage is 1,500 mg Q3W or 1,000 mg Q2W, except in ovarian cancer. Although peripheral edema has occurred with other Ang2 inhibitors, the severity and duration seen here in ovarian cancer potentially identifies a new, clinically significant safety signal for this class of agents. On the basis of limited clinical activity, MEDI3617 development was discontinued. Clin Cancer Res; 24(12); 2749–57. ©2018 AACR.

2563 Background: Treatment with ICIs can manifest immune-related adverse events (irAEs), which have correlated with clinical outcomes in certain tumors. However, timing of these events and how early irAEs correlate with outcomes is unclear. We assessed whether early occurring irAEs could predict survival in pts treated with durvalumab (D), an anti-PDL1 and combined with tremelimumab (D+T), an anti-CTLA4 in two clinical studies. Methods: Two phase 2 non-randomized clinical trials evaluating D (D4190C00001 (1108), N=756; available data per internal data re-use policy) or D+T (D4190C00010 (C10), N=327; expansion and ICI naïve cohorts) in multiple solid tumor types were analyzed. Prevalence of pts experiencing irAEs, regardless of grade was 30% and 59% in studies 1108 and C10, respectively, with most frequent including dermatitis/rash (25%), thyroid (15%), diarrhea/colitis (14%), and pancreatic enzyme elevation (5%). Overall survival (OS) was correlated with irAE timing prior to 6, 8, 12, 16, 20 and 24 weeks following D or D+T treatment. Kaplan Meier and log-rank analyses were used. Results: In both studies, pts who experienced at least one irAE by study completion had improved median OS (mOS, 1108: 23.1 mos [18.2, 26.9]; C10: 16.3 mos [12.5, 31.4]) relative to those who experienced none (1108: 6.3 mos [5.4, 7.3]; C10 4.6 mos [3.3, 6.1]). Median time (weeks) to first and second irAE occurred earlier in C10 compared to 1108, 3.9 vs. 5.6 and 6.9 vs. 10.1, respectively. When associating timing of irAEs with survival, there was a significant differential in mOS at each time interval evaluated between pts with at least one irAE and those with none, with differentiation at 6 weeks and maximal survival benefit at 24 weeks following treatment with D or D+T (Table). Conclusions: Early occurrence of irAEs may be predictive of survival benefit in pts treated with D or D+T. OS by 1+ or no irAE(s) occurring up to 6 or 24 weeks post treatment. [Table: see text]

The aim of this study is to define the maximum tolerated dose (MTD), safety, pharmacokinetics (PKs) and efficacy of ispinesib (SB-715992) in combination with docetaxel. Patients with advanced solid tumours were treated with ispinesib (6-12 mg m(-2)) and docetaxel (50-75 mg m(-2)). Docetaxel was administered over 1 h followed by a 1-h infusion of ispinesib on day 1 of a 21-day schedule. At least three patients were treated at each dose level. Blood samples were collected during cycle 1 for PK analysis. Clinical response assessments were performed every two cycles using RECIST guidelines. Twenty-four patients were treated at four dose levels. Prolonged neutropaenia and febrile neutropaenia were dose limiting in six and two patients, respectively. The MTD was ispinesib 10 mg m(-2) with docetaxel 60 mg m(-2). Pharmacokinetic assessment demonstrated concentrations of ispinesib and docetaxel, consistent with published data from single agent studies of the drugs. Seven patients (six hormone refractory prostate cancer (HRPC), one renal cancer) had a best response of stable disease (>or=18 weeks). One patient with HRPC had a confirmed >50% prostatic-specific antigen decrease. The MTD for ispinesib and docetaxel was defined and the combination demonstrated an acceptable toxicity profile. Preliminary PK data suggest no interaction between ispinesib and docetaxel.

1. Pazopanib (Votrient) is an oral tyrosine kinase inhibitor that was recently approved for the treatment of renal cell carcinoma and soft tissue sarcoma. 2. In this two-part study, we investigated the metabolism, disposition of [(14)C]pazopanib, and the oral bioavailability of pazopanib tablets in patients with advanced cancer. 3. In part A, three men each received a single oral dose of [(14)C]pazopanib in suspension (400 mg, 70 µCi). Pazopanib was the predominant drug-related component in circulation. Two metabolites derived from hydroxylation and one from N-demethylation were also circulating, but were minor, each accounting for

Several phase III trials have shown that the addition of an antiangiogenic agent to conventional chemotherapy can improve clinical benefit in patients with advanced solid tumors. This study examined the feasibility of combining pazopanib (Votrient), an oral antiangiogenic agent, with paclitaxel and carboplatin. This 3 + 3 dose-escalation phase I study evaluated the maximum-tolerated regimen (MTR) of daily pazopanib in combination with paclitaxel 175 mg/m2 and carboplatin [dosed at area under the curve (AUC) 5 or 6] given every 21 days in patients with advanced solid tumors. Plasma samples were collected to evaluate the effect of pazopanib on the pharmacokinetics of paclitaxel and carboplatin. Thirty-four patients were enrolled. The MTR was paclitaxel 175 mg/m2 and carboplatin AUC5 with pazopanib 200 mg. The most common dose-limiting toxicities were neutropenia and thrombocytopenia. Two patients with esophageal cancer had a complete response and four patients, one each with breast, small-cell lung, pancreatic, and gastroesophageal junction cancer, had partial responses. Pazopanib at 200 mg increased paclitaxel maximal concentration (Cmax) by 43% and carboplatin (AUC5 or AUC6) Cmax by 54%. Paclitaxel and carboplatin given every 21 days at standard doses was not feasible in combination with the monotherapy pazopanib dose of 800 mg daily because of dose-limiting myelosuppression. Coadministration of pazopanib increased exposure to paclitaxel and carboplatin and likely contributed to this effect. Given the antitumor activity of this regimen, further studies are underway to determine a clinically tolerable schedule of pazopanib with paclitaxel and carboplatin. Mol Cancer Ther; 11(8); 1820–8. ©2012 AACR.

Purpose: GSK461364 is an ATP-competitive inhibitor of polo-like kinase 1 (Plk1). A phase I study of two schedules of intravenous GSK461364 was conducted. Experimental Design: GSK461364 was administered in escalating doses to patients with solid malignancies by two schedules, either on days 1, 8, and 15 of 28-day cycles (schedule A) or on days 1, 2, 8, 9, 15, and 16 of 28-day cycles (schedule B). Assessments included pharmacokinetic and pharmacodynamic profiles, as well as marker expression studies in pretreatment tumor biopsies. Results: Forty patients received GSK461364: 23 patients in schedule A and 17 in schedule B. Dose-limiting toxicities (DLT) in schedule A at 300 mg (2 of 7 patients) and 225 mg (1 of 8 patients) cohorts included grade 4 neutropenia and/or grade 3–4 thrombocytopenia. In schedule B, DLTs of grade 4 pulmonary emboli and grade 4 neutropenia occurred at 7 or more days at 100 mg dose level. Venous thrombotic emboli (VTE) and myelosuppression were the most common grade 3–4, drug-related events. Pharmacokinetic data indicated that AUC (area under the curve) and Cmax (maximum concentration) were proportional across doses, with a half-life of 9 to 13 hours. Pharmacodynamic studies in circulating tumor cells revealed an increase in phosphorylated histone H3 (pHH3) following drug administration. A best response of prolonged stable disease of more than 16 weeks occurred in 6 (15%) patients, including 4 esophageal cancer patients. Those with prolonged stable disease had greater expression of Ki-67, pHH3, and Plk1 in archived tumor biopsies. Conclusions: The final recommended phase II dose for GSK461364 was 225 mg administered intravenously in schedule A. Because of the high incidence (20%) of VTE, for further clinical evaluation, GSK461364 should involve coadministration of prophylactic anticoagulation. Clin Cancer Res; 17(10); 3420–30. ©2011 AACR.

Pazopanib is an oral angiogenesis inhibitor of vascular endothelial growth factor (VEGF) receptor, platelet-derived growth factor receptor, and cytokine receptor. This open-label, randomized, crossover, phase I study evaluated the effect of low- and high-fat meals on the pharmacokinetics (PK) of pazopanib in patients with advanced solid tumors. Patients participated in either the lead-in cohort or randomized food-effect cohort. Patients in the lead-in cohort were administered a single dose of pazopanib 400 mg with a high-fat meal. Patients in the food-effect cohort were randomized to receive single doses of pazopanib 800 mg in fed condition (high- or low-fat meal) or fasting condition, in random sequence 14 days apart. After completion of the study, patients were given the opportunity to continue treatment with daily pazopanib 800 mg. Administration of pazopanib with both low- and high-fat meals increased maximum observed plasma concentration (C(max)) and area under the plasma concentration-time curve (AUC) by approximately twofold as compared with the corresponding values when administered to patients in the fasted condition. Therefore, pazopanib should be administered to patients in the fasted state so as to minimize within- and between-day variability in the systemic exposure to pazopanib in patients with cancer.

Pazopanib, an oral inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-kit kinases, inhibits multiple cytochrome P450 (CYP450) enzymes in vitro. This study in patients with advanced cancer evaluated the effect of pazopanib on CYP450 function by comparing the pharmacokinetics of CYP-specific probe drugs in the presence and absence of pazopanib. The probes used included midazolam (CYP3A specific), warfarin (CYP2C9 specific), omeprazole (CYP2C19 specific), caffeine (CYP1A2 specific), and dextromethorphan (CYP2D6 specific). The estimated ratios of the geometric means (90% confidence interval (CI)) for the area under the curve to the last measurable point (AUC0–t) for these probe drugs with/without pazopanib were as follows: midazolam, 1.35 (1.18–1.54); omeprazole, 0.81 (0.59–1.12); caffeine, 1.00 (0.77–1.30); and S-warfarin, 0.93 (0.84–1.03). The geometric least-squares (LS) mean ratio of urine dextromethorphan:dextrorphan ranged from 1.33 (0–4-h interval) to 1.64 (4–8-h interval). The data suggest that pazopanib is a weak inhibitor of CYP3A4 and CYP2D6 and has no effect on CYP1A2, CYP2C9, and CYP2C19 in patients with advanced cancer. Clinical Pharmacology & Therapeutics (2010) 88 5, 652–659. doi: 10.1038/clpt.2010.158

To determine the maximum-tolerated dose (MTD), dose-limiting toxicity (DLT), safety, pharmacokinetics, and pharmacodynamics of SB-743921 when administered as a 1-h infusion every 21 days to patients with advanced solid tumors or relapsed/refractory lymphoma.Patients who failed prior standard therapy or those without any standard options were eligible. Forty-four patients were enrolled using an initial accelerated dose-escalation phase followed by a standard dose-escalation phase. An additional 20 patients were enrolled at the recommended phase II dose to obtain additional safety and pharmacokinetic data. The doses evaluated ranged from 2 to 8 mg/m(2). The pharmacokinetics of SB-743921 was evaluated at 19 time-points over 48 h following during administration during cycle 1. Toxicity was assessed by the NCI Common Terminology Criteria version 3.0. Response evaluation was performed every 6 weeks.The most common and consistent DLT was neutropenia. Other DLTs observed included hypophosphatemia, pulmonary emboli, SVC syndrome, transaminitis, hyponatremia, and hyperbilirubinemia. The MTD of SB-743921 as a 1-h infusion every 21 days was established as 4 mg/m(2). The maximum plasma concentration and area under the plasma concentration time curve appeared to increase proportionally to dose. One durable objective response was seen in a patient with metastatic cholangiocarcinoma who was on treatment 11 months and 6 patients had stable disease for over four cycles.The recommended phase II dose of SB-743921 on this specific schedule of a 1-h infusion every 3 weeks is 4 mg/m(2). The promising efficacy and lack of severe toxicities in this study warrant the continued development of SB-743921.

Objective: The aims of this study were to investigate the bioequivalence of a new oral topotecan formulation (i.e., proposed commercial formulation) relative to the current oral formulation (formulation used in previous clinical trials), the effect of food on the absorption and disposition of the new oral topotecan and its safety and tolerability in patients with advanced solid tumors. Patients and methods: This was a multi-center, pharmacological Phase I, multiple-dose, randomized, open-label, cross-over bioequivalence study. In the bioequivalence part, 85 patients were randomized to receive either a 4 mg (4 × 1 mg) dose of the new or current formulation on Days 1 or 8. In the food-effect part, 23 patients received a 4 mg (4 × 1 mg) dose of the new formulation in a fasted and fed state. Total topotecan and topotecan lactone were determined and pharmacokinetic data were analyzed by non-compartmental method. Results: Bioequivalence was demonstrated as the 90% confidence intervals of the ratio of the new to current formulation for both the area under the plasma concentration-time curve (AUC) and the maximal drug concentration (C max ) for topotecan lactone were contained within the 0.8 - 1.25 boundary. The AUC and C max were similar in the fed and fasted state whilst food delayed the t max for topotecan lactone and total topotecan. Safety data were collected on all subjects enrolled (n = 108) and were consistent with observations from previous studies of oral topotecan. All subjects experienced at least one adverse event, the majority of which were graded as mild to moderate in severity. Conclusion: The new oral topotecan formulation demonstrated bioequivalence to the current formulation and demonstrated it can be administered to patients with solid tumors in the fed or fasted state with similar systemic exposure.

Purpose: Interleukin-18 (IL-18) is an immunostimulatory cytokine with antitumor activity in preclinical models. A phase I study of recombinant human IL-18 (rhIL-18) was done to determine the toxicity, pharmacokinetics, and biological activities of rhIL-18 administered at different doses in two different schedules to patients with advanced cancer.Experimental Design: Cohorts of three to four patients were given escalating doses of rhIL-18 as a 2-h i.v. infusion either on 5 consecutive days repeated every 28 days (group A) or once a week (group B) for up to 6 months. Toxicities were graded using standard criteria. Blood samples were obtained for safety, pharmacokinetic, and pharmacodynamic measurements.Results: Nineteen patients (10 melanoma and 9 renal cell cancer) were given rhIL-18 in doses of 100, 500, or 1,000 μg/kg (group A) or 100, 1,000, or 2,000 μg/kg (group B). Common side effects included chills, fever, headache, fatigue, and nausea. Common laboratory abnormalities included transient, asymptomatic grade 1 to 3 lymphopenia, grade 1 to 4 hyperglycemia, grade 1 to 2 anemia, neutropenia, hypoalbuminemia, liver enzyme elevations, and serum creatinine elevations. No dose-limiting toxicities were observed. Biological effects of rhIL-18 included transient lymphopenia and increased expression of activation antigens on lymphocytes. Increases in serum concentrations of IFN-γ, granulocyte macrophage colony-stimulating factor, and IL-18–binding protein were observed following dosing.Conclusions: rhIL-18 can be given in biologically active doses by either weekly infusions or daily infusions for 5 days repeated every 28 days to patients with advanced cancer. Toxicity was generally mild to moderate, and a maximum tolerated dose of rhIL-18 by either schedule was not determined.

Ispinesib, a kinesin spindle protein inhibitor, blocks assembly of a functional mitotic spindle, leading to G2/M arrest. Docetaxel promotes tubulin assembly into microtubules while inhibiting microtubule de-polymerization leading to mitotic arrest. Prolonged (or =5 days) Gr 4 neutropenia and/or febrile neutropenia were the observed dose-limiting toxicities with both agents. Both agents are substrates and inhibitors of CYP3A4; thus, the potential for a drug-drug interaction exists. The goal was to fit a Bayesian population PK/PD model to characterize the relationship between the ispinesib/docetaxel combination and absolute neutrophil counts (ANC).Escalating doses of docetaxel (60-75 mg/m(2)) were administered over 1 h followed by a 1-h infusion of escalating doses of ispinesib (8-12 mg/m(2)) on a 21-day schedule. At least 3 pts were treated at each dose level. Limited PK samples were obtained. ANC were measured weekly on days 1, 8, 15, and 22. More ANC samples were taken from some subjects. The PK properties of ispinesib and docetaxel, and the relationship of PK with ANC were investigated using nonlinear mixed-effects models and Bayesian methods. With a limited dataset, informative prior distributions for the model parameters were needed. These prior distributions were formed using information from a previous study for ispinesib, and from the literature for docetaxel.Twenty-four pts were treated in this study. The PK of ispinesib and docetaxel were well characterized by a two-compartment model and a three-compartment model, respectively. There is no obvious PK interaction between ispinesib and docetaxel. The model for ANC consisted of a proliferating compartment, three transit compartments that represented maturation, and a compartment of circulating blood cells. This ANC model has been used previously for ispinesib given as monotherapy, and for other chemotherapeutic drugs in the literature. Using Bayesian methods, the model was successfully fit for the PK of both compounds and the PD simultaneously.The PK/PD model developed for ispinesib/docetaxel, may be used to examine different schedules, doses, and infusion times of both agents. Bayesian methods allow for the use of prior information available for the model parameters.

The advent of molecularly targeted drug discovery has facilitated the identification of a new generation of anti-mitotic therapies that target proteins with specific functions in mitosis. The exquisite selectivity for mitosis and the distinct ways in which these new agents interfere with mitosis provides the potential to not only overcome certain limitations of current tubulin-targeted anti-mitotic drugs, but to expand the scope of clinical efficacy that those drugs have established. The development of these new anti-mitotic drugs as targeted therapies faces significant challenges; nevertheless, these potential therapies also serve as unique tools to dissect the molecular mechanisms of the mitotic-checkpoint response.

The goal of the present analysis is to fit a Bayesian population pharmacokinetic pharmacodynomic (PK–PD) model to characterize the relationship between the concentration of ispinesib and changes in absolute neutrophil counts (ANC). Ispinesib, a kinesin spindle protein (KSP) inhibitor, blocks assembly of a functional mitotic spindle, leading to G2/M arrest. A first time in human, phase I open-label, non-randomized, dose-escalating study evaluated ispinesib at doses ranging from 1 to 21 mg/m2. PK–PD data were collected from 45 patients with solid tumors. The pharmacokinetics of ispinesib were well characterized by a two-compartment model. A semimechanistic model was fit to the ANC. The PK and PD data were successfully modelled simultaneously. This is the first presentation of simultaneously fitting a PK–PD model to ANC using Bayesian methods. Bayesian methods allow for the use of prior information for some system-related parameters. The model may be used to examine different schedules, doses, and infusion times. Clinical Pharmacology & Therapeutics (2007) 81, 88–94. doi:10.1038/sj.clpt.6100021

The potential for an interaction between lapatinib and absorption of the P-glycoprotein (ABCB1) substrate digoxin at a therapeutic dose in breast cancer patients was characterized. Seventeen women with HER2-positive metastatic breast cancer received a single oral 0.5-mg dose of digoxin on days 1 and 9 and oral lapatinib 1500 mg once daily on days 2 through 9. Digoxin pharmacokinetic parameters were determined on day 1 (digoxin administration alone) and on day 9 (coadministration of lapatinib and digoxin), and parameters were compared to determine the effects of lapatinib on digoxin absorption. Concomitant medications that could affect ABCB1 were accounted for. Lapatinib 1500 mg/day increased digoxin absorption approximately 80%, implicating lapatinib inhibition of intestinal ABCB1-mediated efflux. In summary, coadministration of lapatinib with narrow therapeutic index drugs that are substrates of ABCB1 should be undertaken with caution and dose adjustment should be considered.

Purpose: Increased mitogenic signaling and angiogenesis, frequently facilitated by somatic activation of EGF receptor (EGFR; ErbB1) and/or loss of PTEN, and VEGF overexpression, respectively, drive malignant glioma growth. We hypothesized that patients with recurrent glioblastoma would exhibit differential antitumor benefit based on tumor PTEN/EGFRvIII status when treated with the antiangiogenic agent pazopanib and the ErbB inhibitor lapatinib. Experimental Design: A phase II study evaluated the antitumor activity of pazopanib 400 mg/d plus lapatinib 1,000 mg/d in patients with grade 4 malignant glioma and known PTEN/EGFRvIII status not receiving enzyme-inducing anticonvulsants (EIAC). The phase II study used a two-stage Green–Dahlberg design for futility. An independent, parallel phase I component determined the maximum-tolerated regimen (MTR) of pazopanib and lapatinib in patients with grade 3/4 glioma receiving EIACs. Results: The six-month progression-free survival (PFS) rates in phase II (n = 41) were 0% and 15% in the PTEN/EGFRvIII-positive and PTEN/EGFRvIII-negative cohorts, respectively, leading to early termination. Two patients (5%) had a partial response and 14 patients (34%) had stable disease lasting 8 or more weeks. In phase I (n = 34), the MTR was not reached. On the basis of pharmacokinetic and safety review, a regimen of pazopanib 600 mg plus lapatinib 1,000 mg, each twice daily, was considered safe. Concomitant EIACs reduced exposure to pazopanib and lapatinib. Conclusions: The antitumor activity of this combination at the phase II dose tested was limited. Pharmacokinetic data indicated that exposure to lapatinib was subtherapeutic in the phase II evaluation. Evaluation of intratumoral drug delivery and activity may be essential for hypothesis-testing trials with targeted agents in malignant glioma. Clin Cancer Res; 19(4); 900–8. ©2012 AACR.

Recent studies have shown that tumor cells transduced with interleukin-2 (IL-2) or interferon-gamma (IFN-gamma) genes stimulated a potent and specific antitumor immunity in experimental animals. For use as a human vaccine, tumor cells must be inactivated by irradiation to ensure the arrest of their growth. This study was undertaken to examine the effects of irradiation (10,000 rad) on the growth characteristics and vaccine potential of IL-2 and IFN-gamma-modified human melanomas and B16 murine melanoma. Irradiation caused cessation of cell growth and gradual reduction of cell number. Irradiated melanoma cells displayed 1.5 to 10-fold increases in the surface expression of MHC class I and/or class II antigens. The increases in MHC antigens persisted for 7-14 days postirradiation and then declined thereafter. Furthermore, IL-2- and IFN-gamma-transduced melanoma cells showed enhanced expression of the cytokine mRNA and increased cytokine secretion after irradiation. The effect of irradiation on the vaccine potential of the transduced cells was examined in C57BL/ 6 mice by prophylactic immunization and immunotherapy, and in nude mice by mixed transplantation assays. The irradiated, cytokine-transduced B16 cell vaccine was as or more effective than the unirradiated vaccine. These irradiated vaccines protected the animals against a challenging tumorigenic dose of B16 parental cells and suppressed the growth of 4-day-established B16 lung metastases. The ability of the irradiated IL-2-transduced human melanomas to inhibit the growth of admixed parental melanoma cells was retained but was less efficacious than unirradiated cells. The results suggest that irradiation does not abrogate the vaccine potential of IL-2- and IFN-gamma-transduced melanomas. These findings have implications for designing specific active immunotherapy protocols utilizing cytokine gene-modified tumor cells.

e20093Background: Small-cell lung cancer (SCLC) is a very aggressive lung cancer with a high metastatic potential. Many patients with SCLC initially respond to standard-of-care therapy but have rap...

As tyrosine kinase inhibitors have been associated with cardiotoxicity, we evaluated the effect of pazopanib, an inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, on electrocardiographic parameters in patients with cancer.This double-blind, placebo-controlled, parallel-group study randomized patients (N = 96) to moxifloxacin (positive control) or placebo on Day 1 followed by pazopanib or placebo 800 mg/day (fasted) on Days 2-8 and 1,600 mg (with food) on Day 9. Treatment effects were evaluated by baseline-adjusted, time-matched, serial Holter electrocardiograms.Sixty-five patients were evaluable for preplanned analyses. On Day 1, the maximum mean difference in baseline-adjusted, time-matched Fridericia-corrected QT (QTcF) interval in moxifloxacin-treated patients versus placebo was 10.6 ms (90% confidence interval [CI]: 4.2, 17.0). The administration scheme increased plasma pazopanib concentrations approximately 1.3- to 1.4-fold versus the recommended 800 mg once-daily dose. Pazopanib caused clinically significant increases from baseline in blood pressure, an anticipated class effect, and an unexpected reduction in heart rate from baseline that correlated with pazopanib exposure. On Day 9, the maximum mean difference in baseline-adjusted, time-matched QTcF interval in pazopanib-treated patients versus placebo was 4.4 ms (90% CI: -2.4, 11.2). Mixed-effects modeling indicated no significant concentration-dependent effect of pazopanib or its metabolites on QTcF interval.Pazopanib as administered in this study achieved supratherapeutic concentrations, produced a concentration-dependent decrease in heart rate, and caused a small, concentration-independent prolongation of the QTcF interval.

Background: A phase I dose-escalating study of pazopanib was conducted to determine the maximum tolerated dose (MTD), pharmacokinetic/pharmacodynamic relationships, and clinical activity in patients with advanced hepatocellular carcinoma (HCC). Experimental Design: Asian patients (N = 28) were dose escalated on pazopanib (200–800 mg) once daily (QD) on 21-day cycles, with MTD as the primary endpoint using a modified 3 + 3 design. Changes in tumor vasculature were evaluated by dynamic contrast-enhanced MRI (DCE—MRI). Results: Two of five patients at the 800-mg dose level experienced dose-limiting toxicities [grade 3 aspartate aminotransferase (AST)/alanine aminotransferase (ALT) elevations and grade 3 malaise]. The MTD in patients with HCC (Child–Pugh class A) was 600 mg QD. Diarrhea, skin hypopigmentation, and AST elevation were the most commonly reported adverse events at the MTD. Mean Cmax and area under the concentration-time curve (AUC0–6) of pazopanib and its metabolites did not increase dose proportionally across the 200 to 800 mg range. Reductions in IAUGC and Ktrans were shown at all pazopanib doses evaluated, with the greatest reductions at 600 and 800 mg. Although larger DCE-MRI parameter decreases were associated with larger C24 and Cmax values, there was no constant relationship between tumor perfusion decreases measured by DCE-MRI and plasma pazopanib pharmacokinetic parameters. Overall, 19 patients (73%) had either partial response or stable disease. Conclusion: Pazopanib has a manageable safety profile in patients with advanced HCC, and 600 mg was chosen for further development of pazopanib in advanced HCCs. Moreover, pazopanib reduced tumor vessel leakage, as shown by DCE-MRI, indicating a direct effect on HCC vasculature that might be associated with its antitumor activity. Clin Cancer Res; 17(21); 6914–23. ©2011 AACR.

Background Metastatic colorectal cancer (mCRC) is a leading cause of cancer-related mortality in the United States, and new treatment options are needed. This phase I study investigated a novel regimen combining 2 chemotherapy drugs with proven efficacy in mCRC (capecitabine and oxaliplatin) with a tyrosine kinase inhibitor (lapatinib). Lapatinib has already been approved by the US Food and Drug Administration for treatment of selected cases of breast cancer. Patients and methods: Patients with solid tumors responsive to fluoropyrimidines or oxaliplatin were eligible for enrollment. Treatment was given over a 21-day cycle with a fixed dosing of intravenous oxaliplatin of 130 mg/m2 on day 1. Capecitabine and lapatinib were given orally at escalating doses, starting at capecitabine 1500 mg/m2/day on days 1-14 and lapatinib 1000 mg daily on days 1-21. Results Ten patients received treatment per study protocol. All had received previous systemic treatment. Diarrhea was one of the most common side effects and accounted for nearly all grade 3/4 toxicity. The starting dose level was determined to be the maximum tolerated dose. One patient with pancreatic cancer had evidence of a partial response. Three other patients demonstrated stable disease. There were no complete responses. Conclusion Results of this study suggest the regimen of capecitabine, oxaliplatin, and lapatinib has some efficacy in types of advanced or metastatic solid malignancies with known responsiveness to fluoropyrimidines or oxaliplatin. Further research may help determine whether this regimen can improve on the response rates seen with current standard regimens for mCRC.

Purpose. To evaluate the maximum tolerated regimen (MTR), dose-limiting toxicities, and pharmacokinetics of pazopanib, an oral small-molecule tyrosine kinase inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, in combination with paclitaxel. Patients and Methods. Pazopanib was given daily with weekly paclitaxel on days 1, 8, and 15 every 28 days. Dose levels of pazopanib (mg/day)/paclitaxel (mg/m2) were 400/15, 800/15, 800/50, and 800/80. An expanded cohort was enrolled at the MTR. Plasma samples were collected to evaluate the effect of pazopanib, an inhibitor of cytochrome P450 (CYP)3A4, on the pharmacokinetics of paclitaxel, a CYP3A4 and CYP2C8 substrate. Results. Of 26 enrolled patients, 17 were treated at the MTR of 800 mg pazopanib and 80 mg/m2 paclitaxel. Dose-limiting toxicities included a grade 3 abscess and grade 2 hyperbilirubinemia. Other toxicities included elevated liver transaminases and diarrhea. Six patients (23%) had partial responses and 15 patients (58%) had stable disease. Administration of 800 mg pazopanib resulted in a 14% lower paclitaxel clearance and a 31% higher paclitaxel maximal concentration than with administration of paclitaxel alone at 15, 50, and 80 mg/m2. At the MTR, coadministration of 800 mg pazopanib and 80 mg/m2 paclitaxel resulted in a 26% higher geometric mean paclitaxel area under the curve. Conclusion. Pazopanib, at a dose of 800 mg daily, can be safely combined with a therapeutic dose of paclitaxel at 80 mg/m2 when administered on days 1, 8, and 15, every 28 days. The observed greater plasma concentrations of paclitaxel given concurrently with pazopanib suggest that pazopanib is a weak inhibitor of CYP3A4 and CYP2C8.

BACKGROUND: Phase 1 studies demonstrated evidence of recombinant human IL-18 (rhIL-18)-mediated immunomodulatory and clinical activity, and defined a biologically active dose range. METHODS: A phase 2 study of rhIL-18 was conducted in untreated AJCC stage IV melanoma. Patients were randomized to 1 of 3 dose groups (0.01, 0.1, and 1.0 mg/kg/d) of rhIL-18 administered as 5 daily intravenous infusions repeated every 28 days. A 2-stage design with a stopping rule was used. RESULTS: A total of 64 patients (median age, 57.5 years) with metastatic melanoma (M1a/b (30), M1c (34)) were accrued to stage I, and randomized to 3 groups (21 [0.01 mg/kg/d], 21 [0.1 mg/kg/d], 22 [1.0 mg/kg/d]). Five patients experienced 10 grade 3 drug-related adverse events (AEs): polyarthritis (1 subject: 0.01 mg/kg); deep vein thrombosis, pulmonary embolism (1:0.01 mg/kg); cognitive disorder (1:0.1 mg/kg); fatigue, dyspnea, pleural effusion, lymphopenia (1:1.0 mg/kg); fatigue, lymphopenia (1:1.0 mg/kg). One patient experienced a grade 4 AE of increased lipase (0.1 mg/kg) that led to permanent discontinuation from the study. Among 63 subjects evaluable for response, 1 (M1c; 0.01 mg/kg) achieved a partial response after 4 cycles. Four subjects (3 at 0.01 mg/kg and 1 at 1.0 mg/kg) had stable disease maintained for 6 months or longer. Due to the low apparent level of clinical efficacy using RECIST criteria, the study was terminated at the end of stage 1. The median progression free survival for the 3 groups was 7.5 (0.01), 7.4 (0.1), and 7.3 (1.0) weeks. CONCLUSIONS: rIL-18 as tested in this trial was well tolerated, but had limited activity as a single agent in patients with metastatic melanoma. Cancer 2009. © 2009 American Cancer Society.

Purpose: Interleukin-18 (IL-18) is an immunostimulatory cytokine with antitumor activity in preclinical animal models. A phase I study of recombinant human IL-18 (rhIL-18) was done to determine the toxicity, pharmacokinetics, and biological activities of rhIL-18 in patients with advanced cancer.Experimental Design: Cohorts of patients were given escalating doses of rhIL-18, each administered as a 2-hour i.v. infusion on 5 consecutive days. Toxicities were graded using standard criteria. Serial blood samples were obtained for pharmacokinetic and pharmacodynamic measurements.Results: Twenty-eight patients (21 with renal cell cancer, 6 with melanoma, and 1 with Hodgkin's lymphoma) were given rhIL-18 in doses ranging from 3 to 1,000 μg/kg. Common side effects included chills, fever, nausea, headache, and hypotension. Common laboratory abnormalities included transient, asymptomatic grade 1 to 2 neutropenia, thrombocytopenia, anemia, hypoalbuminemia, hyponatremia, and elevations in liver transaminases. One patient in the 100 μg/kg cohort experienced transient grade 3 hypotension and grade 2 bradycardia during the first infusion of rhIL-18. No other dose-limiting toxicities were observed. Plasma concentrations of rhIL-18 increased with increasing dose, and 2.5-fold accumulation was observed with repeated dosing. Biological effects of rhIL-18 included transient lymphopenia and increased expression of activation antigens on lymphocytes and monocytes. Increases in serum concentrations of IFN-γ, granulocyte macrophage colony-stimulating factor, IL-18 binding protein, and soluble Fas ligand were observed. Two patients experienced unconfirmed partial responses after rhIL-18 treatment.Conclusions: rhIL-18 can be safely given in biologically active doses to patients with advanced cancer. A maximum tolerated dose of rhIL-18 was not determined. Further clinical studies of rhIL-18 are warranted.

Vaccination strategies for lymphomas were developed along with one of the first recognized tumor-specific targets, the clonal antigen receptor, composed of unique variable regions known as idiotypes. Human clinical trials of idiotype vaccination have benefited from highly concordant animal models, leading to sequential improvements in design. Evidence of the clinical benefit of idiotype vaccines is strong but formally unproven. Significant progress has been made in our understanding of the basic mechanisms underlying the induction of immune responses, which has led to a proliferation of rationally designed immunotherapeutic strategies. Current research efforts include the development of more convenient methods to produce individual idiotype vaccines, the establishment of definitive proof for clinical efficacy, and the implementation of alternative vaccination strategies, including genetic vaccination and genetically or immunologically modified autologous tumor cells and dendritic cells.

TPS9108 Background: Greater understanding of tumor immunology in melanoma has led to the development of targeted treatments with improved outcomes in patients (pts) with metastatic melanoma (MM). D...

3021 Background: The interaction between PDL1 (B7H1) and its receptor PD-1 on activated T cells plays an important role in the inhibition of T-cell responses and contributes to suppression of antitumor immune responses. Tumor PDL1 expression has been associated with poor outcomes in RCC. This study investigates the correlation between PDL1 tumor expression and outcomes in RCC pts treated with paz. Methods: Using IHC, we retrospectively analyzed baseline FFPE tumor samples for PDL1 from 2 paz RCC studies: a single arm phase II trial and randomized placebo (pbo)-controlled phase III study. PDL1 expression was analyzed by MedTox Laboratories using the anti-PDL1 MouseIgG1 clone 5H1 (Thompson) on the Leica automated IHC platform. Additional dual PDL1/CD68 staining was carried out to delineate tumor and macrophage PDL1 expression. Tumor PDL1 expression was quantified by H-Score (HS) and PDL1+ macrophages were assessed semi-quantitatively. Association between PDL1H scores and PFS was investigated by Kaplan-Meier analysis using optimal cutoff of PDL1tumor HS (minimum p value, log rank test). Results: The optimal cut-point of PD-L1 tumor HS, relative to PFS, was identified as HS > 3. In the phase II study (46 available samples out of 225), HS range was 0-150 and most samples had negative (HS = 0, n = 34, 74%) or low (HS 1-3, n=4, 9%) PDL1 expression. Pts with HS > 3 (n = 8, 17%) had significantly shorter PFS (2.6 mo) than those with HS ≤ 3 (12 mo; p = .0005). In the phase III study (N = 160 available samples: paz, 113 of 290; pbo, 47 of 145), HS range was 0-280. Most patients had negative (n = 122/160, 76%) or low (n = 9/160, 6%) PD-L1 expression, with 18% (29/160) having HS > 3. Pbo-arm pts with HS > 3 (n = 6/47, 13%) had shorter PFS (2.3 vs 5.5 mo p = .0207). Paz-arm pts with HS > 3 (n = 23/113, 20%) trended toward shorter PFS (7.3 vs 11 mo, p = .1405). Conclusions: PDL1 appears to be a prognostic marker with PDL1 HS > 3 associated with shorter PFS. Limitations of the study include the retrospective nature of the analysis with limited pt samples available, low or negative PDL1 expression in the vast majority of pts, and use of archival samples that may not accurately reflect PDL1 status at study entry. Additional results (tumor volume, OS) will be presented.

Background: Recent studies have demonstrated the usefulness of gene-modified tumor cells for immunotherapy. Using the tumorigenic murine fibrosarcoma, MCA 106, we investigated the effects of localized interferon-γ (IFNg) secretion on tumorigenicity and on long-term memory. Methods: The murine IFNg (MuIFNg) gene was introduced into tumor cells. High and low IFNg-secreting clones were isolated. C57BL/6 mice were injected subcutaneously (s.c.) with either parental (P), high or low IFNg-secreting (H- or L-IFNg) cells, and tumor growth was assessed weekly. Spleens were harvested on different days postinjection (p.i.) to assess in vitro cytolytic activity. In parallel, tissues from injection sites were stained with macrophage-, CD4-, and CD8-detecting antibodies. Mice were injected s.c. with H-IFNg MCA106 tumor. After 150 days the animals were rechallenged s.c. with MCA106P in one leg and with irrelevant syngeneic tumor in the other. Results: Both P- and L-IFNg cells had similar growth, whereas the H-IFNg cells never grew. Only splenocytes from the H-IFNg animals showed in vitro CTL activity persisting until day 30 p.i. Histological data revealed a macrophage and CD4+ infiltrate much earlier in the H-IFNg group compared with the P group. Only the irrelevant, syngeneic tumor grew in animals previously injected with H-IFNg cells, whereas both P and irrelevant syngeneic tumors grew in controls. Conclusions: Transduction of MCA106 cells with the MuIFNg gene diminished in vivo tumorigenicity in proportion to the amount of IFNg secreted. Immunization with H-IFNg cells elicited a host response characterized by macrophages and CD4+ cells. Long-term tumor-specific memory was seen after immunization with H-IFNg cells.

Background: Pazopanib (PAZ) is an oral angiogenesis inhibitor targeting VEGFR, PDGFR, and c-Kit with w/ a recommended dose of 800 mg/day as monotherapy. Preclinical activity supports combining PAZ with paclitaxel (P) and carboplatin (C). Safety, PK, and and clinical activity of PAZ with P and and C were evaluated in two Phase I studies. Methods: Two Phase I studies were conducted using a once daily QD regimen of PAZ (200–800 mg), and once every Q21 days of C (AUC 4–6 mg·min/mL) and P (175 mg/m2) to determine the optimally tolerated regimen (OTR) MTD defined as a dose limiting toxicity (DLT) frequency of Results: In Study 1S1, 34 pts (mean age 54; M/F: 17/17; ECOG 0/1: 19/15) were enrolled. Breast (29%) and esophagus (12%) were the most common primary tumor sites. In Study 2S2, 12 pts (mean age 53.754, M/F: 0/12; ECOG 0/1: 8/4) were enrolled. Ovary (50%) and endometrium/uterus (25%) were the most common primary tumor sites. The frequency of adverse events (AEs), regardless of causality, in the 2 studies (1 vs 2), were similar for neutropenia (82% vs 75%) and fatigue (68% vs 75%) and different for nausea (71% vs 50%), thrombocytopenia (68% vs 33%), anemia (65% vs 25%), and abdominal pain (24% vs 50%). The OTR MTD in Study 1S1 was P 175, C AUC 5, and PAZ 200; an OTR MTD was not determined for Study 2S2 due to poor tolerability. In Study 1S1, in the presence of PAZ 200 mg and 400, mg, the AUC (0–23) of C increased by 41 and 31%, respectively and while the Cmax for P increased by 43 and 40%, respectively. Best response in Study 1S1 at the OTRMTD (n=13) was CR [2 pts (15%); 406 and 446 days] and PR [3 pts (23%); 42–208 days]. Conclusions: Full doses of PAZ and C were not tolerated in combination with w/ P due predominantly to hematologicale toxicities in Study 1S1 and to non-hemeatological toxicities in Study 2S2. A drug interaction between PAZ and P and C along with more extensive prior therapy may explain increased myelotoxicity with this triplet in Study 1S1. Based on this PK interaction, lower doses of P and C may still provide adequate therapeutic exposure and better safety profile when combined with a higher dose of PAZ relative to the OTR MTD in study. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A6.

3561 Background: Patients (pts) with advanced hepatocellular carcinoma (HCC) have a poor prognosis. HCC is a highly vascular tumor with increased levels of angiogenic factors including VEGF and VEGFR. Pazopanib (GW786034) is an oral angiogenesis inhibitor targeting VEGFR, PDGFR, and c-Kit. A Phase I study was conducted to determine the maximum tolerated dose (MTD), safety, pharmacokinetics, pharmacodynamics and efficacy of pazopanib in patients with locally unresectable and/or advanced HCC. Methods: Eligibility criteria included unresectable and/or metastatic HCC with at least 1 target lesion, recovery from prior systemic regimens, ECOG PS 0 or 1, Child-Pugh A, and adequate organ function. Doses of pazopanib were escalated from 200 mg once daily (QD) to 800 mg QD in a 3 + 3 design. DCE- MRI was performed to assess changes in tumor permeability. Results: 27 Asian pts have been enrolled at QD doses of 200 (4 pts), 400 (10), 600 (8), 800 (5): median (range) age = 61 (38–76); M/F = 85%/15%; ECOG 0/1 = 59%/41%; 81% with metastatic disease; 67% with Stage IV; 22% with prior systemic therapy, 26% with prior TACE. Most common AEs were: diarrhea (59%; 4% Gr 3); hypertension (44%; 26% Gr 3), cough (19%); fatigue (19%; 4% Gr 3); and hair depigmentation (15%). Hepatobiliary lab abnormalities were: AST elevation (63%; 15% Gr 3), hyperbilirubinemia (63%; 4% Gr 3), ALT elevation (41%; 7% Gr 3), and Alk phos (37%; 4% Gr 3). DLTs were Gr 3 malaise (1 pt) and Gr 3 AST/ALT elevation (1 pt) at 800 mg. MTD was determined to be 600 mg QD. Median (range) days on study was 85 (4–663) overall; 106 days (4–274) at the MTD. Best response was PR in 2 pts (7%; 1 at 800mg, 1 at 600 mg) and SD > 4 mos in 11 pts (41%). Median TTP at the MTD was 137.5 days (4–280 days). Median % change in tumor permeability (Ktrans) following 3 weeks of pazopanib administration at the MTD (5 pts) was 45%. Predose and maximum plasma pazopanib concentrations at 800 mg QD were similar to values observed previously at the same dose. Conclusions: Pazopanib has a manageable safety profile in HCC at the MTD of 600mg QD. Preliminary evidence of antitumor activity was observed. Changes in tumor DCE-MRI parameters were seen following repeated dose pazopanib administration. [Table: see text]

2027 Background: Kinesin spindle protein (KSP) is required for establishment of mitotic spindle bipolarity and cell cycle progression. Ispinesib (SB-715992), a KSP inhibitor, blocks assembly of a functional mitotic spindle leading to G2/M arrest. Carboplatin is a platinum compound that produces predominantly interstrand DNA cross-links. In vivo combination of a platinum-containing agent (cisplatin) and ispinesib resulted in synergistic activity and an increase in maximum tolerated dose (MTD) of ispinesib. In a phase I study of single agent ispinesib on a once every 21-day schedule, the MTD was 18 mg/m2 with prolonged gr 4 neutropenia and febrile neutropenia as DLTs. Methods: Patients (pts) with advanced solid tumors, PS ≤ 1, and ≤ 3 prior chemotherapy regimens were eligible for this study. Escalating doses of carboplatin (AUC 4-6) were administered over 30 minutes followed by a 1-hour infusion of escalating doses of ispinesib (9– 21 mg/m2) on a 21-day schedule. At least 3 pts were treated at each dose level. The primary objectives of this study included characterizing safety and tolerability and defining the optimally tolerated regimen (OTR). Limited pharmacokinetic (PK) samples were obtained. Clinical response assessments per RECIST criteria were performed every 2 cycles. Results: 24 pts [15 M/9 F; median age 63yrs, ECOG PS 1], were treated at 6 dose levels. The most common tumor types were prostate (7) and breast (4). A median of 3 cycles were administered (range 1–7; total 75 cycles). In 17 pts, the most common toxicities were (# pts, [grade]): nausea (10, Gr 1–2), vomiting (8, Gr 1–3), fatigue (8, Gr 1–2), neutropenia (8, Gr 2–4), anemia (7, Gr 1–3), and thrombocytopenia (7, Gr 1–4). Gr 4 thrombocytopenia was the observed DLT in 2 pts [ispinesib (mg/m2)/carboplatin (mg/ml·min) (# pts): 15/6 (1); 18/6 (1). PK assessment of ispinesib and carboplatin will be completed when the OTR has been defined. Unconfirmed minor responses have been observed in 3 pts (breast, prostate, NSCLC) starting at doses of 18/6. Conclusions: Determination of an OTR is ongoing. Ispinesib doses ≥ single agent MTD when combined with carboplatin AUC 6 have an acceptable tolerability profile and demonstrate preliminary evidence of anti-tumor activity. [Table: see text]

10043 Background: Interleukin-18 (IL-18) is an immunostimulatory cytokine with potent antitumor activity in preclinical models. Two phase I studies of recombinant human (rh) IL-18 explored a wide dose range (0.03–1.0 mg/kg) without reaching a maximum tolerated dose (MTD) on the daily × 5 schedule. Pharmacodynamic data including inflammatory cytokine production and activation of lymphocyte subsets revealed optimal biologic activity at the lower end of the dose range (0.01–0.2 mg/kg) as did 2 unconfirmed partial responses (PRs) in a MM and a renal cancer patient (pt) at 0.1 mg/kg. Methods: An open-label, randomized, phase II trial in 60 adult pts with previously untreated MM was conducted to evaluate the efficacy and safety of rhIL-18 administered as a 2-hour IV infusion daily × 5 every 28 days for 6 cycles. Pts with PS ≤ 1, without known CNS involvement, and with adequate end organ function were randomized in stage 1 to 3 dose levels of IL-18 stratified according to AJCC M stage 1a/b vs. 1c. Two confirmed responses for a given dose level in Stage 1 were required to enroll 20 additional pts/level in Stage 2. The 1° objective was determination of overall response rate (ORR) for each dose level. Progression-free survival (PFS), tolerability, and immunogenicity were 2° endpoints. Results: 64 pts were treated at 3 dose levels. Nine pts remain on study. One pt experienced a confirmed PR. Based on preliminary data, the difference in PFS 6 months (mos) was significant (p=0.03) for 0.01 vs 0.1 mg/kg. Most common toxicities were mild to moderate fever, rigors, chills, n/v, and headache. Anti-IL18 antibody (Ab) development correlated with dose level. No clinically significant adverse events were associated with Ab development. Conclusion: Iboctadekin has an acceptable tolerability profile and has activity in MM but insufficient confirmed responses have been observed at this time to initiate Stage 2. Preliminary PFS 6 months indicates an advantage for pts treated at the lowest dose. [Table: see text] [Table: see text]

2000 Background: SB-743921, a potent and selective inhibitor of KSP (Ki =100 pM; >40,000-fold selectivity vs other kinesins), causes mitotic arrest, potent inhibition of tumor cell proliferation, and demonstrates activity in a broad range of human tumor xenografts. Methods: A phase I study was conducted to determine the maximum tolerated dose (MTD) and PK profile of SB-743921 when administered IV over 60 minutes every 21 (Q 21) days (d). Results: 44 patients (pts) (M/F 19/25), median age 61.5 yrs (range 32–80, with solid tumors were treated at doses of 2 (n=2), 4 (n=27), 5 (n=6), 6 (n=3), and 8 (n=6) mg/m2 (median cycles 2, range 1–10, total cycles 101). Frequent tumor types included colorectal (n=11), ovarian (n=5), NSCLC (n=5), esophageal (n=4), and pancreatic (n=4). Dose-limiting toxicities (DLTs) at 8 mg/m2 consisted of (max CTC grade/pt) prolonged grade (gr) 4 neutropenia (n=2), gr 3 elevated ALT/AST (n=1), and gr 3 elevated bilirubin (n=1). DLTs at 6 mg/m2 were gr 3 hyponatremia (n=1) and prolonged gr 4 neutropenia (n=1). DLTs at 5 mg/m2 were limited to febrile neutropenia (n=2). The 4 mg/m2 dose level was determined as the phase II dose. Toxicities at 4 mg/m2 included gr 1 fatigue (n=8) and neutropenia [gr 1 (n=4), gr 2 (n=7), gr 3 (n=3), gr 4 (n=2)]. Neutropenia nadir was day 6–8 with recovery to gr ≤2 by day 15. Gr 3 non-hematologic toxicities at 4 mg/m2 included gr 3 ALT (n=1), gr 3 AST (n=2), gr 3 hyperbilirubinemia (n=1), gr 3 hypophosphatemia (n=1), and gr 3 alkaline phosphatase elevation (n=1). Median PK values in cycle 1 at 4 mg/m2 were: Cmax 473 ng/ml, AUC0-∞ 5207 ng.hr/ml, and t½ 36 hr. AUC0-∞ and Cmax were proportional to dose. No consistent correlation was observed between DLTs and PK parameters. Stable disease for ≥ 4 cycles (range 4–11) was observed in 6 pts (4 pts at 4 mg/m2; 1 pt at 6 mg/m2; 1 pt at 8 mg/m2). A pt with cholangiocarcinoma had evidence of radiographic tumor regression (post cycle 10) and a >50% decrease in her CA 19–9. Conclusions: The recommended phase II dose of SB-743921 on the Q 21 day schedule is 4 mg/m2. The observed toxicities at the recommended phase II dose are manageable and reversible. The onset and duration of neutropenia is predictable. [Table: see text]

2513 Background: rhIL-18, a potent immunomodulatory cytokine, has demonstrated anti-tumor activity in a variety of preclinical models. Depending on the model employed, multiple mediators appear to ...

2535 Background: rhIL-18, a potent immunomodulatory cytokine, has demonstrated anti-tumor activity in a variety of preclinical models. Clinical safety and biological activity were examined in a pre...