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Pokharel S.,Premiere Oncology | Rana S.,Proton Therapy | Blikenstaff J.,Premiere Oncology | Sadeghi A.,Arizona Radiation Oncology Specialists | Prestidge B.,Memorial Hermanan Healthcare System
Journal of Applied Clinical Medical Physics | Year: 2013

The purpose of this study is to investigate the effectiveness of the HIPO planning and optimization algorithm for real-time prostate HDR brachytherapy. This study consists of 20 patients who underwent ultrasound-based real-time HDR brachytherapy of the prostate using the treatment planning system called Oncentra Prostate (SWIFT version 3.0). The treatment plans for all patients were optimized using inverse dose-volume histogram-based optimization followed by graphical optimization (GRO) in real time. The GRO is manual manipulation of isodose lines slice by slice. The quality of the plan heavily depends on planner expertise and experience. The data for all patients were retrieved later, and treatment plans were created and optimized using HIPO algorithm with the same set of dose constraints, number of catheters, and set of contours as in the real-time optimization algorithm. The HIPO algorithm is a hybrid because it combines both stochastic and deterministic algorithms. The stochastic algorithm, called simulated annealing, searches the optimal catheter distributions for a given set of dose objectives. The deterministic algorithm, called dose-volume histogram-based optimization (DVHO), optimizes three-dimensional dose distribution quickly by moving straight downhill once it is in the advantageous region of the search space given by the stochastic algorithm. The PTV receiving 100% of the prescription dose (V100) was 97.56% and 95.38% with GRO and HIPO, respectively. The mean dose (Dmean) and minimum dose to 10% volume (D10) for the urethra, rectum, and bladder were all statistically lower with HIPO compared to GRO using the student pair t-test at 5% significance level. HIPO can provide treatment plans with comparable target coverage to that of GRO with a reduction in dose to the critical structures.


Socinski M.A.,University of Pittsburgh | Goldman J.,Premiere Oncology | El-Hariry I.,Synta Pharmaceuticals | Koczywas M.,City of Hope | And 19 more authors.
Clinical Cancer Research | Year: 2013

Purpose: Ganetespib is a novel inhibitor of the heat shock protein 90 (Hsp90), a chaperone protein critical to tumor growth and proliferation. In this phase II study, we evaluated the activity and tolerability of ganetespib in previously treated patients with non-small cell lung cancer (NSCLC). Experimental Design: Patients were enrolled into cohort A (mutant EGFR), B (mutant KRAS), or C (no EGFR or KRAS mutations). Patients were treated with 200 mg/m2 ganetespib by intravenous infusion once weekly for 3 weeks followed by 1 week of rest, until disease progression. The primary endpoint was progression-free survival (PFS) at 16 weeks. Secondary endpoints included objective response (ORR), duration of treatment, tolerability, median PFS, overall survival (OS), and correlative studies. Results: Ninety-nine patients with a median of 2 prior systemic therapies were enrolled; 98 were assigned to cohort A (n = 15), B (n = 17), or C (n = 66), with PFS rates at 16 weeks of 13.3%, 5.9%, and 19.7%, respectively. Four patients (4%) achieved partial response (PR); all had disease that harbored anaplastic lymphoma kinase (ALK) gene rearrangement, retrospectively detected by FISH (n = 1) or PCR-based assays (n = 3), in crizotinib-naïve patients enrolled to cohort C. Eight patients (8.1%) experienced treatment-related serious adverse events (AE); 2 of these (cardiac arrest and renal failure) resulted in death. The most common AEs were diarrhea, fatigue, nausea, and anorexia. Conclusions: Ganetespib monotherapy showed a manageable side effect profile as well as clinical activity in heavily pretreated patients with advanced NSCLCs, particularly in patients with tumors harboring ALK gene rearrangement.©2013 AACR.


Johnson F.M.,University of Texas M. D. Anderson Cancer Center | Agrawal S.,Bristol Myers Squibb | Burris H.,Sarah Cannon Cancer Center | Rosen L.,Premiere Oncology | And 8 more authors.
Cancer | Year: 2010

BACKGROUND: The recently developed the Src and Abelson (Abl) kinase inhibitor dasatinib has antitumor effects in epithelial and mesenchymal tumors. Preclinical data have indicated that dasatinib is metabolized primarily through cytochrome P450 3A4 (CYP3A4) and may cause QT prolongation. In light of its improved tolerability, the authors were interested in the safety of a once-daily dasatinib regimen. METHODS: The authors conducted a phase 1 trial of dasatinib in 29 patients with advanced solid tumors. Segment 1 of the trial was short term and sequential and was designed to determine whether the coadministration of the potent CYP3A4 inhibitor ketoconazole had an effect on the pharmacokinetics of dasatinib. Segment 2 was designed to evaluate the safety of dasatinib as dosing was increased. QT intervals were monitored closely in both segments. Efficacy was assessed in Segment 2 using both positron emission tomography and computed tomography. RESULTS: Hematologic toxicities were markedly less than those observed in patients with leukemia, whereas nonhematologic toxicities were similar. The authors determined that the maximum recommended dose was 180 mg once daily based on the incidence of pleural effusion. Coadministration of ketoconazole led to a marked increase in dasatinib exposure, which was correlated with an increase in corrected QT (QTc) values of approximately 6 msec. No adverse cardiac events were observed. CONCLUSIONS: The dose-limiting toxic effect for dasatinib was pleural effusion. The pharmacokinetic and cardiac studies indicated that coadministration of dasatinib with potent CYP3A4 inhibitors or agents that prolong the QTc interval should be avoided if possible. Close monitoring for toxicity and dose reduction should be considered if the coadministration of such agents cannot be avoided. © 2010 American Cancer Society.


Jhaveri K.,Sloan Kettering Cancer Center | Jhaveri K.,New York University | Miller K.,Indianapolis Cancer Center | Rosen L.,Premiere Oncology | And 9 more authors.
Clinical Cancer Research | Year: 2012

Purpose: We conducted a phase I dose-escalation study to define the maximum tolerated dose (MTD), pharmacokinetics (PK), and pharmacodynamics of alvespimycin (17-DMAG), a heat shock protein 90 (Hsp90) inhibitor, given in combination with trastuzumab. Experimental Design: Patients were treated with trastuzumab followed by intravenous alvespimycin on a weekly schedule. Hsp90 client proteins were measured at baseline and serially in peripheral blood lymphocytes (PBL) during cycle 1. Patients with advanced solid tumors progressing on standard therapy were eligible. Results: Twenty-eight patients (25, breast; 3, ovarian) were enrolled on to three dose cohorts: 60 (n = 9), 80 (n = 13), and 100 mg/m2 (n = 6). Dose-limiting toxicities (DLT) were: grade III left ventricular systolic dysfunction presenting as congestive heart failure in 1 patient (100 mg/m2), and reversible grade III keratitis in two patients (80 mg/m2). Drug-related grade III toxicity included one episode each of fatigue, diarrhea, myalgia, and back pain. Common mild to moderate toxicities included diarrhea, fatigue, myalgia, arthralgia, nausea, blurry vision, headache, back pain, and dry eyes. There was one partial response and seven cases of stable disease (range, 4-10 months), all inHER2+ MBC. In addition, an ovarian cancer patient had complete resolution of ascites and pleural effusion that lasted 24.8 months. There was no change in PK upon weekly dosing. Hsp70 effect continued to increase across four weeks and was most pronounced at 80 and 100 mg/m2. Conclusion: The combination of alvespimycin and trastuzumab is safe and tolerable at MTD. Antitumor activity was seen in patients with refractory HER2+ MBC and ovarian cancer. The recommended dose of alvespimycin for further study in this combination is 80 mg/m2 weekly. ©2012 AACR.


Gerber D.E.,University of Texas Southwestern Medical Center | Stopeck A.T.,Arizona Cancer Center | Wong L.,Scott and White Hospital | Rosen L.S.,Premiere Oncology | And 3 more authors.
Clinical Cancer Research | Year: 2011

Purpose: Bavituximab is a chimeric immunoglobulin G1 phosphatidylserine- targeting monoclonal antibody that triggers vascular disruption and enhances antitumor immune response. This phase I study assessed the safety and pharmacokinetics of bavituximab in patients with advanced solid tumors. Experimental Design: Patients with refractory advanced solid tumors were enrolled into four sequential dose-escalation cohorts (0.1, 0.3, 1, or 3 mg/kg bavituximab weekly) with two dosing schedules. Patients in the 0.1 and 0.3 mg/kg cohorts received bavituximab on days 0, 28, 35, and 42. Patients in the 1 and 3 mg/kg cohorts were administered bavituximab on days 0, 7, 14, and 21. Safety, pharmacokinetics, and tumor response were assessed. Results: Twenty-six patients were accrued. No maximum tolerated dose was reached. Six serious adverse events occurred in five patients, including one pulmonary embolism at 3 mg/kg, which was the only dose-limiting toxicity (DLT) in the study. Bavituximab half-life ranged from 37 to 47 hours, with no accumulation seen following administration of multiple doses. Activated partial thromboplastin time was modestly prolonged in vitro at the highest dose tested. As assessed on day 56, a total of 18 patients were evaluable for efficacy, of whom 10 had disease progression and none had an objective response. Conclusions: Bavituximab was well tolerated at doses ranging up to 3 mg/kg weekly. Pharmacokinetic studies support a weekly dosing regimen. Additional phase I and II clinical trials are in progress to investigate bavituximab in combination with chemotherapy and other molecularly targeted agents. ©2011 AACR.


Infante J.R.,Sarah Canon Research Institute | Rugg T.,SGX Pharmaceuticals | Gordon M.,Premiere Oncology | Rooney I.,SGX Pharmaceuticals | And 5 more authors.
Investigational New Drugs | Year: 2013

Summary: Purpose SGX523 is an orally bio-available, ATP competitive, small molecule inhibitor of MET, binding the kinase domain active site in a novel mode. Two phase 1, open-label, dose-escalation studies of SGX523 were conducted to evaluate both interrupted and continuous dosing schedules. Methods Thirty-six patients per study were planned to be enrolled. The first study explored a 21-day cycle with SGX523 administered on an intermittent schedule at a starting dose of 60 mg PO BID for 14 days followed by 7 days of rest. The second protocol explored a continuous 28-day dosing schedule with SGX523 administered at a starting dose of 20 mg PO BID for 28 days without rest. Results A total of 10 patients were enrolled, 2 on the intermittent dosing protocol and 8 on the continuous dosing protocol. All 6 patients that received daily doses of ≥ 80 mg developed unexpected renal failure manifested by an early rise of serum blood urea nitrogen and creatinine. Human PK analysis revealed the formation of two insoluble metabolites at levels not seen in the rat or dog preclinical toxicology studies. Subsequent primate toxicology and toxicokinetic evaluation replicated human findings, and histological examination of the monkey kidneys revealed the formation of crystals both within the renal tubules and within giant cell macrophages. Conclusion Two-species toxicology studies of SGX523 did not predict the occurrence of renal toxicity in the human. Subsequent primate toxicology studies suggest the cause of the renal failure seen in humans was a crystal nephropathy secondary to insoluble metabolites. SGX523 is no longer in clinical development. © 2012 Springer Science+Business Media, LLC.


Rosen L.S.,Premiere Oncology | Puzanov I.,Vanderbilt University | Friberg G.,Amgen Inc. | Chan E.,Vanderbilt University | And 12 more authors.
Clinical Cancer Research | Year: 2012

Purpose: This phase 1b dose-escalation study assessed safety, tolerability, and pharmacokinetics of ganitumab, a fully human monoclonal antibody against the insulin-like growth factor 1 (IGF1) receptor, combined with targeted agents or cytotoxic chemotherapy in patients with advanced solid tumors. Experimental Design: Patients with treatment-refractory advanced solid tumors were sequentially enrolled at 2 ganitumab dose levels (6 or 12 mg/kg i.v. every 2 weeks) combined with either sorafenib 400 mg twice daily, panitumumab 6 mg/kg every 2 weeks, erlotinib 150 mg once daily, or gemcitabine 1,000 mg/m2 on days 1, 8, and 15 of each 4-week cycle. The primary end points were safety and pharmacokinetics of ganitumab. Results: Ganitumab up to 12 mg/kg appeared well tolerated combined with sorafenib, panitumumab, erlotinib, or gemcitabine. Treatment-emergent adverse events were generally mild and included fatigue, nausea, vomiting, and chills. Three patients had dose-limiting toxicities: grade 3 hyperglycemia (ganitumab 6 mg/kg and panitumumab), grade 4 neutropenia (ganitumab 6 mg/kg and gemcitabine), and grade 4 thrombocytopenia (ganitumab 12 mg/kg and erlotinib). Ganitumab-binding and panitumumab-binding antibodies were detected in 5 and 2 patients, respectively; neutralizing antibodies were not detected. The pharmacokinetics of ganitumab and each cotherapy did not appear affected by coadministration. Circulating total IGF1 and IGF binding protein 3 increased from baseline following treatment. Four patients (9%) had partial responses. Conclusions: Ganitumab up to 12 mg/kg was well tolerated, without adverse effects on pharmacokinetics in combination with either sorafenib, panitumumab, erlotinib, or gemcitabine. Ganitumab is currently under investigation in combination with some of these and other agents. ©2012 AACR.


Houk B.E.,Pfizer | Bello C.L.,Pfizer | Poland B.,Pharsight | Rosen L.S.,Premiere Oncology | And 2 more authors.
Cancer Chemotherapy and Pharmacology | Year: 2010

Purpose: In this pharmacokinetic/pharmacodynamic metaanalysis, we investigated relationships between clinical endpoints and sunitinib exposure in patients with advanced solid tumors, including patients with gastrointestinal stromal tumor (GIST) and metastatic renal cell carcinoma (mRCC). Methods: Pharmacodynamic data were available for 639 patients of whom 443 had pharmacokinetic data. Sunitinib doses ranged from 25 to 150 mg QD or QOD. Models to express endpoint values and/or changes from baseline by the highest-correlating exposure measures were developed in S-PLUS or NONMEM using fixed- and mixed-effects modeling. Results: Tentative relationships were identified between (1) steady-state AUC of total drug (sunitinib + its active metabolite SU12662) and time to tumor progression (TTP), overall survival (OS), with AUC significantly associated with longer TTP and OS in patients with GIST and mRCC, and incidence, but not severity, of fatigue; (2) steady-state AUC of sunitinib and response probability, with AUC significantly associated with objective response in patients with mRCC and stable disease in patients with both mRCC and GIST (with no such correlations in patients with solid tumors); (3) dose and tumor size reductions; (4) total drug concentration and diastolic blood pressure (DBP), with a typical patient on sunitinib 50 mg QD (the recommended dose) predicted to experience a maximum DBP increase of 8 mmHg; and (5) cumulative AUC of total drug and absolute neutrophil count (ANC), with ANC reductions occurring predominantly after one treatment cycle. Conclusions: The results of this meta-analysis indicate that increased exposure to sunitinib is associated with improved clinical outcomes (longer TTP, longer OS, greater chance of antitumor response), as well as some increased risk of adverse effects. A sunitinib 50-mg starting dose seems reasonable, providing clinical benefit with acceptably low risk of adverse events.


Background and Purpose: Recently, megavoltage (MV) photon volumetric modulated arc therapy (VMAT) has gained widespread acceptance as the technique of choice for prostate cancer patients undergoing external beam radiation therapy. However, radiation treatment planning for patients with metallic hip prostheses composed of high-Z materials can be challenging due to (1) presence of streak artifacts from prosthetic hips in computed tomography dataset, and (2) inhomogeneous dose distribution within the target volume. The purpose of this study was to compare the dosimetric quality of VMAT techniques in the form of Rapid Arc (RA) for treating low-risk prostate cancer patient with bilateral prostheses. Materials and Methods: Three treatment plans were created using RA techniques utilizing 2 arcs (2-RA), 3 arcs (3-RA), and 4 arcs (4-RA) for 6 MV photon beam in Eclipse treatment planning system. Each plan was optimized for total dose of 79.2 Gy prescribed to the planning target volume (PTV) over 44 fractions. All three RA plans were calculated with anisotropic analytical algorithm. Results : The mean and maximum doses to the PTV as well as the homogeneity index among all three RA plans were comparable. The plan conformity index was highest in the 2-Arc plan (1.19) and lowest in the 4-Arc plan (1.10). In comparison to the 2-RA technique, the 4-RA technique reduced the doses to rectum by up to 18.8% and to bladder by up to 7.8%. In comparison to the 3-RA technique, the 4-RA technique reduced the doses to rectum by up to 14.6% and to bladder by up to 3.5%. Conclusion: Based on the RA techniques investigated for a low-risk prostate cancer patient with bilateral prostheses, the 4-RA plan produced lower rectal and bladder dose and better dose conformity across the PTV in comparison with the 2-RA and 3-RA plans. © 2014. The South Asian Journal of Cancer.


Rosen L.S.,Premiere Oncology | Ashurst H.L.,ACUMED | Chap L.,Premiere Oncology
Oncologist | Year: 2010

Greater understanding of the underlying etiology and biology of breast cancer is enabling the clinical development of targeted therapies for metastatic breast cancer (MBC). Following the successful introduction of trastuzumab, the first human epidermal growth factor receptor (HER) biologically targeted therapy to become widely used in MBC patients, other agents have been developed. Novel agents include monoclonal antibodies such as pertuzumab, which bind to receptors on the cell surface, and tyrosine kinase inhibitors (TKIs) such as lapatinib, which target intracellular pathways such as that of the epidermal growth factor receptor. There is also growing clinical experience with antiangiogenic agents, particularly in combination with chemotherapy. These include the monoclonal antibody bevacizumab, which targets vascular endothelial growth factor receptor, and multitargeted TKIs with antiangiogenic and antiproliferative activities, such as sunitinib. Combination treatment with multiple agents targeting both the HER family and angiogenic pathways (e.g., trastuzumab plus bevacizumab) is also showing activity in the clinical setting. Despite recent advances, there are unanswered questions regarding the management of MBC with targeted agents. Future studies are necessary to determine the optimal combinations, doses, and schedules required to maximize clinical activity while minimizing toxicity. Despite the temptation to use a targeted agent in all patients, identification of patient subgroups most likely to benefit must be a key goal and will be critical to the successful future use of these treatments. The aim of this review is to summarize some of the key signaling pathways involved in tumor progression and some of the novel therapies that are in development for MBC. ©AlphaMed Press.

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