Efficacy of vemurafenib (V), a selective V600EBRAF inhibitor, as monotherapy or in combination with erlotinib (Erl) or erbitux (Erb) and irinotecan (Iri) doublets and triplets in a colorectal cancer (CRC) xenograft model.

2012 ◽  
Vol 30 (4_suppl) ◽  
pp. 494-494
Author(s):  
Brian Higgins ◽  
Kenneth Daniel Kolinsky ◽  
Kathleen Schostack ◽  
Gideon Bollag ◽  
Richard J. Lee ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Mapk Pathway ◽  
Single Agent ◽  
Xenograft Model ◽  
Optimal Dose ◽  
Tumor Growth Inhibition ◽  
Egfr Inhibition ◽  
Final Study ◽  
Molecule Inhibitor ◽  
Better Than

494 Background: B-Raf mutations, particularly at V600 occur in 10% of CRCs resulting in constitutive activation of the MAPK pathway. V (RG7204, PLX4032) is a first-in-class, V600B-Raf-selective small molecule inhibitor previously shown to potentiate anti-tumor effects in the V600E CRC xenograft model HT29 in combination (combo) with capecitabine ± bevacizumab (ASCO GI, 2008). V600E CRC respond poorly to EGFR inhibition (EGFRi) both preclinically and clinically. We aimed to determine whether antitumor activity could be potentiated by combining V with EGFRi. Methods: The monotherapy (mono) activities of V, Erl, Erb and Iri were compared to combo of these agents in the HT29 model. V was tested as a mono at its optimal dose (OD), Erl was tested at its MTD or 2/3 MTD, and a combo of V OD + 2/3 MTD Erl were tested. V was subsequently tested as mono or combo at the OD and suboptimal-OD with OD Erb. A final study included Iri as mono, doublets of Iri + V or Erb, and triplet combo of Iri, V, and Erb. Results: Tumor growth inhibition (TGI) and increase in life span (ILS) for combo of OD V + 2/3 MTD Erl was superior to all mono arms. TGI in mono arms was equivalent for V, Erb and Iri. ILS was better for V vs Iri and Erb mono, while Iri vs Erb ILS were equivalent. TGI and ILS for Iri + Erb doublet was equivalent to V mono. Otherwise, TGI and ILS in all other doublets and triplets were superior to mono groups. TGI in V + Erb and V + Iri were equivalent, but ILS was better for V + Iri. TGI and ILS for V + Iri was better than Iri + Erb. TGI in V + Erb was better than Iri + Erb, but ILS was equivalent. TGI in the triplet was superior to all doublets except V + Erb, however ILS was superior to all doublets tested. Conclusions: V potentiates anti-tumor activity in a V600E CRC model when used in combo with Erl, Erb and Iri. Although a V + Erb doublet provided impressive TGI equivalent to a triplet with Iri, the triplet yielded sustained antitumor activity as demonstrated by a significant increase in survival as compared to the doublet. Combo with V may afford V600E CRC patients a differential response to what is seen traditionally with single agent EGFi and is worthy of clinical exploration.

In vivo activity of R1530 (R) alone and in combination with bevacizumab (B) and peginterferon alfa-2a (P) in a renal cell carcinoma (RCC) xenograft model

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e14629-e14629
Author(s):  
B. Higgins ◽  
K. Packman ◽  
Y. Zhang ◽  
H. Char ◽  
M. Simcox ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Tumor Growth ◽  
Growth Inhibition ◽  
Cancer Cell ◽  
Single Agent ◽  
Xenograft Model ◽  
Human Tumor ◽  
Tumor Growth Inhibition ◽  
High Dose ◽  
Wide Range

e14629 Background: R1530 is a multikinase inhibitor currently in clinical phase I testing. Its inhibitory profile includes several kinases that play critical roles in cancer cell growth and division as well as tumor angiogenesis. These properties translate into a potent cytotoxicity in a wide range of cancer cell lines in vitro and tumor growth inhibition in human tumor xenografts. Preclinical studies were conducted to evaluate the effects of R alone and in combination with B and P in the Caki-1 RCC xenograft model. Methods: We initially evaluated the antitumor activity of optimal dose (OD) and 1/2 OD R alone and with OD B. This was followed up with testing of OD & 1/2 OD P ± OD B, along with triplets of 1/2 OD P + OD B + 1/2 OD R and OD P + OD B + 1/2 OD R. A final study compared 1/2 OD R to OD R triplets to attempt to increase tumor growth inhibition (TGI) and increase life span (ILS). Results: No doublets or triplets tested showed antagonism or enhanced toxicity. Antitumor activity and survival results are listed below (Table). Conclusions: 1/2 OD R + OD B or OD R + OD B doublets gave better TGI and ILS than monotherapy. Comparing these two doublets, TGI is better in the high dose combination but ILS is equivalent. All TGI and ILS are better in doublet P + B combinations over respective single agent arms except for TGI (but not ILS) for 1/2 OD P vs its correlative doublet with B. The OD P + B doublet gave better TGI and ILS than 1/2 OD P + B doublet. TGI and ILS do not differ between triplets containing OD R + 1/2 OD or OD P or for triplets containing the OD P + 1/2 OD or OD R. Therefore, either agent can be alternatively dose reduced without a loss of tumor response or detriment to survival in this preclinical model of RCC. [Table: see text] [Table: see text]

scholarly journals APTO-253 Induces KLF4 to Promote Potent in Vitro Pro-Apoptotic Activity in Hematologic Cancer Cell Lines and Antitumor Efficacy As a Single Agent and in Combination with Azacitidine in Animal Models of Acute Myelogenous Leukemia (AML)

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 4813-4813 ◽  
Author(s):  
William G Rice ◽  
Avanish Vellanki ◽  
Yoon Lee ◽  
Jeff Lightfoot ◽  
Robert Peralta ◽  
...  
Keyword(s):  
Bone Marrow ◽  
High Risk ◽  
Animal Models ◽  
Antitumor Activity ◽  
Single Agent ◽  
Xenograft Model ◽  
Myelogenous Leukemia ◽  
Acute Myelogenous ◽  
Xenograft Models

Abstract APTO-253, a small molecule that mediates anticancer activity through induction of the Krüppel-like factor 4 (KLF4) tumor suppressor, is being developed clinically for the treatment of acute myelogenous leukemia (AML) and high risk myelodysplastic syndromes (MDS). APTO-253 was well tolerated in a Phase I study in patients with solid tumors using a dosing schedule of days 1, 2, 15, 16 of a 28 day cycle (2T-12B-2T-12B), but recent scientific observations guided APTO-253 toward AML and high risk MDS. Indeed, suppression of KLF4 was reported as a key driver in the leukemogenesis of AML and subsets of other hematologic diseases. The vast majority (~90%) of patients with AML aberrantly express the transcription factor CDX2 in human bone marrow stem and progenitor cells (HSPC) (Scholl et al., J Clin Invest. 2007, 117(4):1037-48). The CDX2 protein binds to CDX2 consensus sequences within the KLF4 promoter, thereby suppressing KLF4 expression in HSPC (Faber et al., J Clin Invest. 2013, 123(1):299-314). Based on these observations, the anticancer activity of APTO-253 was examined in AML and other hematological cancers. APTO-253 showed potent antiproliferative activity in vitro against a panel of blood cancer cell lines, with ηM IC50values in AML (6.9 - 305 ηM), acute lymphoblastic leukemia and chronic myeloid leukemia (39 – 250 ηM), non-Hodgkin’s lymphoma (11 – 190 ηM) and multiple myeloma (72 – 180 ηM). To explore in vivo efficacy, dose scheduling studies were initially conducted in the H226 xenograft model in mice. In the H226 model, APTO-253 showed improved antitumor activity when administered for two consecutive days followed by a five day break from dosing (2T-5B) each week, i.e. on days 1,2, 8,9, 15,16, 22,23, compared to the 2T-12B-2T-12B schedule. The 2T-5B schedule was used to evaluate antitumor activity of APTO-253 in several AML xenograft models in mice. In Kasumi-1 AML and KG-1 AML xenograft models, APTO-253 showed significant antitumor activity (p = 0.028 and p=0.0004, respectively) as a single agent when administered using the 2T-5B schedule each week for four weeks compared to control animals. Mice treated with APTO-253 had no overt toxicity based on clinical observations and body weight measurements. Mice bearing HL-60 AML xenograft tumors were treated with APTO-253 for one day or two consecutive days per week for three weeks, either as a single agent or combined with azacitidine, or with azacitidine alone twice per week (on days 1,4, 8, 11, 15 and 18). APTO-253 as a single agent inhibited growth of HL-60 tumors to approximately the same extent as azacitidine. Furthermore, both once weekly and twice weekly dosing of APTO-253 in combination with azacitidine resulted in significantly enhanced antitumor activity relative to either single agent alone (p = 0.0002 and p = 0.0006 for 1X and 2X weekly APTO-253 treatment, respectively, compared to control). Likewise, using a THP-1 AML xenograft model, APTO-253 administered as a single agent using the 2T-5B per week schedule showed significant efficacy, similar to that of azacitidine, while the combination of APTO-253 and azacitidine demonstrated greatly improved antitumor effects relative to either drug alone. APTO-253 was effective and well tolerated as a single agent or in combination with azacitidine in multiple AML xenograft models, plus APTO-253 does not cause bone marrow suppression in animal models or humans. Taken together, our results indicate that APTO-253 may serve as a targeted agent for single agent use and may provide enhanced efficacy to standard of care chemotherapeutics for AML and other hematological malignancies. Disclosures Rice: Lorus Therapeutics Inc.: Employment. Vellanki:Lorus Therapeutics Inc.: Employment. Lee:Lorus Therapeutics Inc.: Employment. Lightfoot:Lorus Therapeutics Inc.: Employment. Peralta:Lorus Therapeutics Inc.: Employment. Jamerlan:Lorus Therapeutics Inc.: Employment. Jin:Lorus Therapeutics Inc.: Employment. Lum:Lorus Therapeutics Inc.: Employment. Cheng:Lorus Therapeutics Inc.: Employment.

IMAGE, a randomized phase Ib/II study of elisidepsin (E) as a single agent in pretreated advanced gastroesophageal (GE) cancer.

2013 ◽  
Vol 31 (4_suppl) ◽  
pp. 92-92 ◽  
Author(s):  
Ramon Salazar ◽  
Jean Philippe Metges ◽  
David Alan Anthoney ◽  
Gianluca Laus ◽  
Maria Alsina Maqueda ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Phase Ii ◽  
Single Agent ◽  
Progression Free Survival ◽  
Optimal Dose ◽  
Primary Objective ◽  
Phase Ib ◽  
Flat Dose

92 Background: E is a new marine compound with broad in vitro/in vivo antitumor activity. Low μM concentrations lead to cell-death through membrane permeabilization. E has shown evidence of activity in pre-treated GE patients (pts) in phase I trials. Methods: The primary objective was to determine the tolerability and efficacy of E in pts with GE cancer after 1-2 prior chemotherapy (CT) lines. Initially, dose was optimized (Phase Ib) in two different schedules: a fixed flat dose (FD) of intravenous (i.v) E (8 and 10 mg), in 24h, biweekly (Arm A) and i.v E (3.0 and 3.75mg), in 3h, weekly (Arm B). After dose optimization patients were included and stratified by histology to each optimal dose (Phase II) to determine the rate of progression-free survival at week 16 ± 1 (PFS4) in an intention to treat analysis. If at least two out of 15 pts reached PFS4, recruitment would continue to a maximum of 40 pts per arm. Results: A total of 45 pts were recruited, 12 pts into Phase Ib (Arm A/B: 6/6 pts) and 33 pts into Phase II (Arm A/B: 15/18 pts). Median age was 60 years (35–81 years), 39 were males and ECOG PS was 1 in 75% of pts. Tumour sites were gastric (32% pts), esophageal (39% pts) and esophago-gastric junction (30% pts). Ninety percent of pts had metastatic disease, 31.8% of which had liver metastasis; 55% of pts had two prior lines of CT . No DLTs occurred during the first cycle in the Phase Ib. The optimal dose for Arm A was 10 mg FD, 24h, biweekly; the optimal dose for Arm B was 3.75mg FD, 3h, weekly. Two patients reached PFS4 in Phase Ib (Arm A). Only one patient reached PFS4 in Phase II (Arm A). No objective responses were observed. Therefore, protocol criteria for further recruitment were not met. The safety profile showed grade 1-2 toxicity pruritus (29.5%), nausea (15.9%), vomiting (6.8%) and fatigue (25%). Grade 3-4 toxicity consisted of asymptomatic reversible liver enzyme increases in 20.5% of patients. Conclusions: E is a very tolerable drug with a unique mechanism of action. In the current setting of non-stratified advanced GE patients, E has insufficient antitumor activity to warrant further investigation. Clinical trial information: 2010-020325-40.

scholarly journals The CDK9 Inhibitor, Alvocidib, Potentiates the Non-Clinical Activity of Azacytidine or Decitabine in an MCL-1-Dependent Fashion, Supporting Clinical Exploration of a Decitabine and Alvocidib Combination

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4355-4355
Author(s):  
Wontak Kim ◽  
Clifford Whatcott ◽  
Adam Siddiqui-Jain ◽  
Stephen Anthony ◽  
David J. Bearss ◽  
...  
Keyword(s):  
Protein Expression ◽  
Cell Viability ◽  
Single Agent ◽  
Xenograft Model ◽  
Complete Response ◽  
Tumor Growth Inhibition ◽  
Phase 2 ◽  
Phase 1B ◽  
Cdk9 Inhibitor

Abstract The hypomethylating agents (HMAs) azacytidine and decitabine exert biological activity via two distinct mechanisms, namely, DNA damage and inhibition of DNA methyltransferases. Azacytidine and decitabine are indicated in the treatment of patients with myelodysplastic syndromes (MDS). As a result of DNA methyltransferase inhibition, it is hypothesized that HMAs may function by inducing re-expression of key pro-apoptotic proteins such as NOXA, which sequesters the anti-apoptotic protein MCL-1, preventing its association with the mitochondrial pore-forming proteins BAX/BAK. Activity of the potent CDK9 inhibitor, alvocidib, is largely driven by targeting of CDK9-dependent MCL-1 expression. Alvocidib is under active clinical investigation, but has also has demonstrated high complete response rates in newly diagnosed AML patients, particularly when administered as part of a cytarabine and mitoxantrone containing regimen (ACM regimen). Given the dual NOXA/MCL-1-targeting ability of combining alvocidib and azacytidine or decitabine, the combination may synergize therapeutically in the treatment of non-clinical models of AML or MDS by means of transcriptional induction of NOXA and repression of MCL-1 expression. Cell viability and induction of apoptosis was assessed following treatment with alvocidib, azacytidine, and decitabine in cells using the Celltiter-Glo and Caspase-Glo assays. Gene expression changes following treatment were assessed using quantitative RT-PCR. Protein expression changes with treatment were also measured using standard immunoblotting technique. To assess the in vivo anti-tumor activity of these compounds, xenograft studies in the MOLM13 and additional models of MDS, exploring sequencing and scheduling of alvocidib administration with HMAs, were performed. Treatment of AML cell lines with alvocidib inhibited both mRNA and protein expression of MCL-1 in a time and concentration-dependent fashion. Pre-treatment of cells with alvocidib, to repress MCL-1 expression prior to azacytidine treatment, reduced the azacytidine cell viability EC50 more than 2.5-fold, from 1.8 µM to 0.6 µM in MV4-11 cells. The alvocidib/azacytidine combination also resulted in synergistic increases in caspase activity relative to either single agent within the combination, at multiple dose levels. The combination of azacytidine or decitabine with alvocidib was active in the MOLM13 xenograft model, yielding up to 65.7 or 91.1% tumor growth inhibition (%TGI) in the azacytidine or decitabine combination, respectively. Taken together, the in vitro and in vivo studies indicated that decitabine was more effective at re-expressing NOXA and potentiating alvocidib activity compared to azacytidine. These non-clinical data suggest that an alvocidib/HMA combination may constitute a viable therapeutic regimen whose rationale focuses on hypertargeting of NOXA/MCL-1. Based on these non-clinical results, a Phase 1b/2 clinical study of alvocidib administered in sequence after decitabine in patients with intermediate to high risk MDS is being conducted (Zella 102). Patients will be enrolled in cohorts of 3-6 patients with decitabine administered as a 1-hour IV infusion daily on days 1 to 5 at a dose of 20 mg/m2 followed by a single alvocidib treatment on day 8 as a loading dose over 30 minutes followed by a 4-hour infusion. Treatment will be repeated every 28 days until disease progression or unacceptable toxicity. Enrollment will include MDS patients (Phase 1b) with previously untreated MDS and patients who received fewer than six (6) cycles of previous HMAs, as well as (Phase 2) untreated patients with de novo or secondary MDS. The primary objective is to determine the maximum tolerated dose and recommended Phase 2 dose of alvocidib when administered in sequence with decitabine. Key Phase 2 endpoints will include complete response rate and improvement in transfusion dependency. Disclosures Kim: Tolero Pharmaceuticals, Inc: Employment. Whatcott:Tolero Pharmaceuticals, Inc: Employment. Siddiqui-Jain:Tolero Pharmaceuticals, Inc: Employment. Anthony:Tolero Pharmaceuticals, Inc: Employment. Bearss:Tolero Pharmaceuticals, Inc: Employment. Warner:Tolero Pharmaceuticals: Employment.

scholarly journals Research in vivo the qualities of potential antitumor amino-acid derivatives of glycosides of indolocarbazol

2017 ◽  
Vol 16 (4) ◽  
pp. 85-92 ◽  
Author(s):  
I. S. Golubeva ◽  
N. P. Yavorskaya ◽  
O. V. Goryunova
Keyword(s):  
Amino Acid ◽  
Antitumor Activity ◽  
Optimal Dose ◽  
Amino Acid Derivatives ◽  
Tumor Growth Inhibition ◽  
Active Metabolites ◽  
Derivatives Of ◽  
Potential Antitumor

Background. The addition of active metabolites (in particular, amino acids) to the molecule affects the physicochemical and prodrug properties of derivatives of indolocarbazoles. Using computed chemoinformatics, probability antitumor activity of amino-acid derivatives of glycosides of indolocarbazol (AADGI) is predicted with low probability of their cytotoxic activity in vitro. Based on these data, a study of these compounds in vivo is conducted. Objective: the assessment of AADGI as potential antitumor medications. Materials and methods. Research antitumor activity of AADGI was done using murine tumor models - cervical cancer CC-5. Investigated compounds were injected to mice СВА abdominally 5-times daily with interval of 24 h. Observation of animals were continued till their death. Antitumor effect of compounds was assessed by criteria of tumor growth inhibition and increase in life expectancy of mice comparing to control animals. Results. The optimal dose for these series of compounds was titrated and this dose is 100 mg/kg. Antitumor activity of AADGI was assessed on CC-5. Conclusions. Based on data received we suggest an extended study in vivo of antitumor qualities of selected 5 leader AADGI.

First-in-human study of the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of PF-00299804, a small molecule irreversible panHER inhibitor in patients with advanced cancer

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 3599-3599 ◽  
Author(s):  
J. H. Schellens ◽  
C. D. Britten ◽  
D. R. Camidge ◽  
D. Boss ◽  
S. Wong ◽  
...  
Keyword(s):  
Small Molecule ◽  
Tyrosine Kinases ◽  
Human Study ◽  
Xenograft Model ◽  
Tumor Growth Inhibition ◽  
Her Family ◽  
Molecule Inhibitor ◽  
Hand Foot Syndrome ◽  
Fdg Pet Ct ◽  
Dose Levels

3599 Background: There are scientific rationale for inhibitors which provide combined and irreversible blockade of HER family members. PF-00299804 is an orally available, potent, irreversible small molecule inhibitor of the HER tyrosine kinases. Methods: The safety, tolerability, PK, PD, and efficacy of PF-00299804 administered orally once daily in 3-week cycles were assessed in patients with advanced solid tumors using an accelerated dose-escalation design. Safety assessments included adverse event (AE), laboratory, ECG, and LVEF assessments. PK parameters were determined after a single lead-in dose and on Day 14 by non-compartmental techniques. PD measures included assessment of HER-related signaling pathways via IHC analyses of serial skin and, in some patients, tumor biopsies. Serial 18F-FDG- PET/CT has been performed on a subset of patients with scans being classified according to modified EORTC criteria by a central reader. Results: 32 pts have been treated across 8 sequential dose levels ranging from 0.5 to 60 mg. The most common AEs were diarrhea, fatigue, nausea, and rash. 3/6 patients at 60 mg experienced a DLT [hand-foot syndrome (1), dehydration related to diarrhea(1), mucositis(1)]. Cmax and AUC of PF-00299804 increased with dose in an approximately proportional manner. Accumulation ranged from 3.3 to 6.8, suggesting a terminal t1/2>24 h. At the 30 mg dose level, mean Day 14 drug concentration was above the predicted efficacious concentration for tumor growth inhibition based on A431 xenograft model. Of 7 sets of PET data evaluated thus far, partial responses (PR) have been observed in 2 patients. A PR as assessed using RECIST criteria has been reported in 1 of 2 patients with advanced refractory NSCLC treated to date. Conclusions: Daily administration of PF-00299804 across many dose levels appears safe and tolerable. Diarrhea, fatigue, nausea, and rash are the most frequent AEs. Evaluation of 45 mg/d as the potential MTD is ongoing. Systemic exposures at doses = 30 mg exceed the threshold for efficacy as predicted from preclinical studies. Clinical and biological activity of PF-00299804 was observed including a PR in 1 of 2 patients with advanced refractory NSCLC. No significant financial relationships to disclose.

Compared Antitumor Activity of GA101 and Rituximab against the Human RL Follicular Lymphoma Xenografts in SCID Beige Mice.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1585-1585 ◽  
Author(s):  
Stéphane Dalle ◽  
Lina Reslan ◽  
Stéphanie Brunet Manquat ◽  
Franck Herting ◽  
Christian Klein ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Combined Therapy ◽  
Single Agent ◽  
Antitumor Efficacy ◽  
Fixed Dose ◽  
Tumor Growth Inhibition ◽  
Type I ◽  
Mice Model ◽  
Anti Cd20

Abstract GA101 is a third generation, glycoengineered type II IgG1 anti-CD20 monoclonal antibody (Mab) with enhanced ADCC and superior caspase-independent apoptosis induction in comparison to other anti-CD20 antibodies, including rituximab which is a type I antibody. We compared the antitumor efficacy of GA101 and rituximab in established RL human lymphoma xenografts in SCID beige mice. One million exponentially growing RL cells were injected SC, yielding fast growing xenografts. GA101 was given twice weekly at 3 dosages (10, 30 and 100 mg/kg), whereas Rituximab was given at fixed dose of 30 mg/kg twice weekly. Both Mabs were administered as intravenous injections, for a total of 5 injections. GA101 was dose-related active against RL xenografts in terms of tumor growth inhibition (TGI). TGI was calculated using NCI formula and showed values of 25, 75 and 85% for the 10, 30 and 100 mg/kg dosages of GA101 respectively while the 30 mg/kg dose of rituximab induced a TGI of 43% only. Both higher doses of 30 and 100 mg/kg significantly inhibited the growth of RL tumors and resulted in some complete tumor remissions (10–30 %). The antitumor activity of Rituximab against RL xenografts was inferior to equivalent dosing of GA101. Toxicity of GA101 with these regimens was excellent with no toxic deaths and no significant modification of body weight. In a separate series of experiments rituximab 30 mg/kg and GA101 30 mg/kg administered once weekly i.v. for 4 weeks were combined or not to cyclophosphamide 50 mg/kg administered once weekly intraperitoneally for 4 weeks. This study confirmed the previous observation that the new anti CD20 GA101 was more active than rituximab administered at similar doses on established RL tumors. TGI values were 79, 35% and 93% for GA101, rituximab and cyclophosphamide administered as single agents when compared to untreated controls. When groups receiving combined therapy were compared to the groups receiving the corresponding single agent Mab, cyclophosphamide increased antitumor efficacy with TGI values of 83 and 94% for rituximab and GA101, respectively. Thus using a suboptimal dose of the classical antilymphoma alkylating agent cyclophosphamide, the combination of either antibody with cyclophosphamide was more active than either agent alone, and the most active combination was GA101 with cyclophosphamide. These results show that GA101 is more active than rituximab on RL xenografts at similar doses, both administered as a single agent or in combination with cyclophosphamide. In the SCID mice model it is not expected that a major contribution to antitumor efficacy comes from the interaction of glycoengineered Mab with murine FcgRIV receptors. Complementary experiments with cobra venom factor, which is used for in vivo complement inhibition, suggest that rituximab antitumor effect was strongly dependent on complement dependent cytotoxicity while GA101 remained active when complement was depleted.

In vivo activity of R1530 (R) alone and in combination with docetaxel (D) and bevacizumab (B) in a prostate carcinoma (PCa) xenograft model

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e16124-e16124
Author(s):  
K. D. Kolinsky ◽  
Y. Zhang ◽  
K. Packman ◽  
B. Higgins
Keyword(s):  
Xenograft Model ◽  
Optimal Dose ◽  
P Value ◽  
Clinical Testing ◽  
Cancer Cell Growth ◽  
Multikinase Inhibitor ◽  
R And D ◽  
Final Study ◽  
M Phase

e16124 Background: R is a multikinase inhibitor currently in phase I clinical testing. Its inhibitory profile includes several kinases that play critical roles in cancer cell growth and division leading to disruption at M-phase and antiangiogenic effects. Studies were conducted to evaluate the efficacy and tolerability of R alone and in combination with D and B in the 22rv1 androgen independent PCa model. Methods: Initially TGI of optimal dose (OD) R, D and B were evaluated. Then the TGI and increased life span (ILS) of the minimum efficacious dose (MED) and 2/3 OD R ± 2/3 OD D was tested. A final study compared doublets of 2/3 OD R + 2/3 OD D, 2/3 OD D + OD B, 2/3 OD R + OD B, and triplet of 2/3 OD D + 2/3 OD R+ 2/3 OD B. Results: All treatment groups were tolerated and there was no antagonism. TGI and ILS results are listed below ( Table ). Conclusions: The OD of R B and D showed monotherapy TGI in this model. MED R + 2/3 OD D gave ILS statistically better (sb) than singlets but TGI was sb than MED R but not the D singlet. 2/3 OD R + 2/3 OD D produced sb TGI and ILS than each singlet. TGI and ILS with 2/3 OD R is sb than 2/3 OD D. TGI and ILS of 2/3 OD R + 2/3 OD D was sb than the 2/3 OD D + OD B but not the 2/3 OD R + B doublet. TGI and ILS was sb for 2/3 OD R + OD B versus 2/3 OD D + OD B. The TGI of the triplet was equivalent to the 2/3 OD R + 2/3 OD D doublet, but ILS was sb in the triplet. Also, the TGI and ILS was sb for triplet versus 2/3 OD D + OD B. TGI and ILS of the triplet was equal to 2/3 OD R + OD B. In general, the results demonstrate that the shared mechanism of mitotic disruption by R and D do not render antagonism, but in fact, allow for potentiated TGI and ILS. Also of note is the equally superior TGI and ILS provided by R + B and R + B + D. In general, the preclinical results generated support clinical testing of these agents in PCa. * p value for all. [Table: see text] [Table: see text]

Combined EGFR targeted therapy in a novel in vivo pancreas cancer model

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 14063-14063
Author(s):  
A. Jimeno ◽  
A. Chan ◽  
B. Rubio-Viqueira ◽  
X. Zhang ◽  
G. Cusatis ◽  
...  
Keyword(s):  
Drug Evaluation ◽  
Single Agent ◽  
Xenograft Model ◽  
Egfr Inhibitors ◽  
Egfr Mutations ◽  
Proliferation Index ◽  
Pathway Activation ◽  
Molecule Inhibitor ◽  
Genomic Markers

14063 Background: EGFR inhibitors have a definite but limited activity in pancreatic cancer (PaCa). We have reported enhanced activity of dual EGFR therapy with a small molecule inhibitor (erlotinib) plus a monoclonal antibody (cetuximab) in head and neck cancer models. Human xenografted tumors recapitulate better the pathobiology of cancer than existing cell lines. Here we explored a dual EGFR targeting approach using a direct PaCa xenograft model, and sought after markers predicting efficacy. Methods: PaCa specimens obtained at the time surgery were implanted in nude mice and expanded to develop cohorts of tumor bearing mice suitable for drug evaluation. Ten cases were expanded, and within each case 4 groups of 6–8 mice each were treated with vehicle, erlotinib, cetuximab, and the combination of both for 28 days. Gene mutation analysis, gene amplification by fluorescence-in-situ hybridization, and immunohistochemistry (IHC) were done with untreated samples. Results: Two cases were sensitive to both single agents, but the combination did not induce higher efficacy in those. Two additional cases that were resistant to both single agents became sensitive with the combination. No egfr mutations were detected. Three and four cases carried low and high egfr polysomy (defined as [[Unsupported Character - ]] 4 copies in 10–40% and [[Unsupported Character - ]] 40% of the cells, respectively). No correlation was found between egfr copy number and efficacy. By IHC sensitive cases had a lower Ki67 proliferation index, and higher EGFR and nuclear pMAPK staining than resistant cases. The degree of Ki67 decrease after therapy correlated with efficacy. In cases resistant to the single agents but sensitive to the combination nuclear pMAPK only decreased with the dual targeting. Cases with high egfr polysomy were more labile to pharmacodynamic effects after treatment (such as EGFR or pMAPK decreases). Conclusions: EGFR inhibitors showed modest single agent antitumor effect that was enhanced with dual EGFR therapy in PaCa. No genomic markers predicted efficacy, although high egfr polysomy was associated with deeper pharmacodynamic inhibition, conceivably suggesting a phenomenon of pathway addiction. Higher pathway activation by IHC was linked with higher activity. No significant financial relationships to disclose.

Combined activity of the cancer metabolism inhibitor MPC-8640 and 5-fluorouracil in xenograft models.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e13581-e13581
Author(s):  
Vijay R. Baichwal ◽  
Chad Bradford ◽  
J. Scott Patton ◽  
Leslie Reeves ◽  
Lynn DeMie ◽  
...  
Keyword(s):  
Colon Carcinoma ◽  
Cancer Metabolism ◽  
Tumor Regression ◽  
Single Agent ◽  
Xenograft Model ◽  
Tumor Growth Inhibition ◽  
Tumoricidal Activity ◽  
Xenograft Models ◽  
Carcinoma Xenograft

e13581 Background: Nicotinamide (Nam) phosphoribosyltransferase (Nampt) catalyzes the rate-limiting step in NAD biosynthesis from Nam. Nampt inhibition causes NAD depletion, inhibition of ATP synthesis and cell death. MPI-0487316 is a selective Nampt inhibitor with potent tumoricidal activity against cancer cell lines of diverse origin. MPC-8640, an orally bioavailable prodrug of MPI-0487316, induces regressions in xenograft models. Combining Nampt inhibitors with 5-fluorouracil (5-FU) results in synergistic tumoricidal activity in cells. We have explored the combination of MPC-8640 with 5-FU in a colon carcinoma xenograft model. Methods: In vitro studies were done in HCT-116 human colon carcinoma cells. Cell viability was measured by determining ATP levels. Xenograft studies were done with cells implanted subcutaneously into athymic mice (nu/nu). MPC-8640 was dosed orally at 12 to 48 mg/kg daily on Days 1-7 and 15-21. 5-FU was dosed intraperitoneally, weekly at 100 mg/kg. Results: MPI-0487316 showed synergistic tumoricidal activity in vitro with 5-FU. In xenograft studies, the prodrug MPC-8640, at 12, 24 and 36 mg/kg, resulted in tumor growth inhibition (TGI) of 64%, 98% and 91%, respectively, at the end of dosing on Day 22 and tumor regression of 5%, when dosed at 48 mg/kg. In the 36 and 48 mg/kg group, 20% and 10% of the mice, respectively, had no detectable tumors by the end of the study on Day 42. In another study, mice were given 5-FU or MPC-8640 as single agents or in combination. Combining 5-FU with MPC-8640 at 24 mg/kg resulted in 45% tumor regression on Day 21 compared to TGI of 88% and 78% for MPC-8640 or 5-FU, respectively, dosed as single agents. Similarly, combining 5-FU and MPC-8640 at 32 mg/kg resulted in 83% tumor regression on Day 21 compared to TGI of 86% and 78% for MPC-8640 and 5-FU, respectively, dosed as single agents. The combinations of 5-FU and MPC-8640 were well-tolerated with <10% change in median body weight. Conclusions: A combination of MPC-8640 with 5-FU causes tumor regression in a colon carcinoma xenograft model and is more effective than either agent dosed alone. Thus, MPC-8640 may have potential for treating cancers as a single agent or in combination with antimetabolites.

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