A phase I, dose-escalation study of pomalidomide (CC-4047) in combination with gemcitabine in metastatic pancreas cancer

Clinical Trials Targeting the Stroma in Pancreatic Cancer: A Systematic Review and Meta-Analysis

The tumor microenvironment plays an important role in the initiation and progression of pancreatic adenocarcinoma (PDAC). In this systematic review, we provide an overview of clinical trials with stroma-targeting agents. We systematically searched MEDLINE/PubMed and the EMBASE database, using the PRISMA guidelines, for eligible clinical trials. In total, 2330 records were screened, from which we have included 106 articles. A meta-analysis could be performed on 51 articles which describe the targeting of the vascular endothelial growth factor (VEGF) pathway, and three articles which describe the targeting of hyaluronic acid. Anti-VEGF therapies did not show an increase in median overall survival (OS) with combined hazard ratios (HRs) of 1.01 (95% confidence interval (CI) 0.90-1.13). Treatment with hyaluronidase PEGPH20 showed promising results, but, thus far, only in combination with gemcitabine and nab-paclitaxel in selected patients with hyaluronic acid (HA)high tumors: An increase in median progression free survival (PFS) of 2.9 months, as well as a HR of 0.51 (95% CI 0.26-1.00). In conclusion, we found that anti-angiogenic therapies did not show an increased benefit in median OS or PFS in contrast to promising results with anti-hyaluronic acid treatment in combination with gemcitabine and nab-paclitaxel. The PEGPH20 clinical trials used patient selection to determine eligibility based on tumor biology, which underlines the importance to personalize treatment for pancreatic cancer patients.

Pomalidomide Alters Pancreatic Macrophage Populations to Generate an Immune-Responsive Environment at Precancerous and Cancerous Lesions

During development of pancreatic cancer, alternatively activated macrophages contribute to fibrogenesis, pancreatic intraepithelial neoplasia (PanIN) lesion growth, and generation of an immunosuppressive environment. Here, we show that the immunomodulatory agent pomalidomide depletes pancreatic lesion areas of alternatively activated macrophage populations. Pomalidomide treatment resulted in downregulation of interferon regulatory factor 4, a transcription factor for M2 macrophage polarization. Pomalidomide-induced absence of alternatively activated macrophages led to a decrease in fibrosis at PanIN lesions and in syngeneic tumors; this was due to generation of an inflammatory, immune-responsive environment with increased expression of IL1α and presence of activated (IFNγ-positive) CD4⁺ and CD8⁺ T-cell populations. Our results indicate that pomalidomide could be used to decrease fibrogenesis in pancreatic cancer and may be ideal as a combination treatment with chemotherapeutic drugs or other immunotherapies. SIGNIFICANCE: These findings reveal new insights into how macrophage populations within the pancreatic cancer microenvironment can be modulated, providing the means to turn the microenvironment from immunosuppressive to immune-responsive.

Pomalidomide enhanced gemcitabine and nab-paclitaxel on pancreatic cancer both in vitro and in vivo

Background

Chemotherapy with gemcitabine and nab-paclitaxel (gemcitabine/nab-paclitaxel) is recommended for unresectable pancreatic cancer. However, the therapeutic efficacy is attenuated by the antitumor agent-induced activation of nuclear factor-κB (NF-κB). Thalidomide inhibits NF-κB activation, therefore, we hypothesized that pomalidomide, a third-generation IMiD, would also inhibit NF-κB activation and enhance the antitumor effects of gemcitabine/nab-paclitaxel.

Methods

In vitro, we assessed NF-κB activity and apoptosis in response to pomalidomide alone, gemcitabine/nab-paclitaxel, or combination of pomalidomide and gemcitabine/nab-paclitaxel in human pancreatic cancer cell lines (PANC-1 and MIA PaCa-2). In vivo, we established orthotopic model and the animals were treated with oral pomalidomide and injection of gemcitabine/nab-paclitaxel.

Results

In pomalidomide and gemcitabine/nab-paclitaxel group, gemcitabine/nab-paclitaxel-induced NF-κB activation was inhibited and apoptosis was enhanced in comparison with those in the other groups both in vitro and in vivo. Especially, this study revealed for the first time that pomalidomide enhances p53 on pancreatic cancer cells. The tumor growth in the pomalidomide and gemcitabine/nab-paclitaxel group was significantly slower than that in the gemcitabine/nab-paclitaxel group. Moreover, pomalidomide induced G0/G1 cell cycle arrest and suppressed angiogenesis.

Conclusions

Pomalidomide enhanced the antitumor effect of gemcitabine/nab-paclitaxel by inhibition of NF-κB activation. This combination regimen would be a novel strategy for treating pancreatic cancer.

Pomalidomide promotes chemosensitization of pancreatic cancer by inhibition of NF-κB

Introduction

Nuclear factor κB (NF-κB) plays an important role in cancer progression and causes therapeutic resistance to chemotherapy. Pomalidomide, a third-generation immunomodulating drug derived from thalidomide, has been approved for uncontrolled multiple myeloma. We hypothesized that pomalidomide may inhibit the anticancer agent-induced NF-κB activity and enhance chemosensitization of combination chemotherapy with gemcitabine and S1 (Gem/S1) in pancreatic cancer.

Methods

In vitro, we assessed NF-κB activity, induction of caspase cascade, cell apoptosis and cell proliferation using human pancreatic cancer cell lines (MIA PaCa-2 and PANC-1). In vivo, we established an orthotopic xenograft mouse model for human pancreatic cancer by injection of PANC-1 cells. At 5 weeks after injection, the animals were randomly divided into four groups and treated with Gem (100 mg/kg) /S1 (10 mg/kg), with oral administration of pomalidomide (0.5 mg/kg), with combination of gemcitabine, S1, and pomalidomide or vehicle only.

Results

Although chemotherapeutic agents induced NF-κB activation in pancreatic cancer cells, pomalidomide inhibited anticancer agent-induced NF-κB activation (p < 0.01). Of the four groups tested for the apoptosis-related caspase signals and apoptosis under both in vitro and in vivo conditions, Gem/S1/Pomalidomide group demonstrated the strongest activation of the caspase signals and proapoptotic effect. In Gem/S1/Pomalidomide group, cell proliferation and tumor growth were slower than those in other groups both in vitro and in vivo (p < 0.01). There were no obvious adverse effects except for thrombocytosis by using pomalidomide.

Conclusions

Pomalidomide promotes chemosensitization of pancreatic cancer by inhibiting chemotherapeutic agents-induced NF-κB activation.

Clinical and Immune Effects of Lenalidomide in Combination with Gemcitabine in Patients with Advanced Pancreatic Cancer

Purpose

To assess the immunomodulatory and clinical effects of lenalidomide with standard treatment of gemcitabine in patients with advanced pancreatic cancer.

Patients and Methods

Patients with advanced pancreatic cancer were treated in first line with lenalidomide orally for 21 days of a 28 days cycle and the standard regimen for gemcitabine. In Part I, which we previously have reported, the dose of lenalidomide was defined (n = 12). In Part II, every other consecutive patient was treated with either lenalidomide (Group A, n = 11) or gemcitabine (Group B, n = 10) during cycle 1. From cycle 2 on, all Part II patients received the combination.

Results

A significant decrease in the proliferative response of peripheral blood mononuclear cells and the frequency of DCs were noted in patients at baseline compared to healthy control donors while the frequencies of CD4+ and CD8+ T cells, NK-cells and MDSCs were significantly higher in patients compared to controls. In Group A, a significant increase in the absolute numbers of activated (HLA-DR+) CD4 and CD8 T cells and CD8 effector memory T cells (p<0.01) was noted during treatment. A statistical increment in the absolute numbers of Tregs were seen after cycle 1 (p<0.05). The addition of gemcitabine, reduced most lymphocyte subsets (p<0.05). In Group B, the proportion of lymphocytes remained unchanged during the study period. There was no difference in overall survival, progression free survival and survival rate at one year comparing the two groups.

Discussion

Patients with advanced pancreatic carcinoma had impaired immune functions. Lenalidomide augmented T cell reactivities, which were abrogated by gemcitabine. However, addition of lenalidomide to gemcitabine seemed to have no therapeutic impact compared to gemcitabine alone in this non-randomized study.

Trial Registration

ClinicalTrials.gov NCT01547260

A phase I dose-escalation study of lenalidomide in combination with gemcitabine in patients with advanced pancreatic cancer

Purpose

Lenalidomide have both immunomodulatory and anti-angiogenic properties which could confer anti-cancer effects. The aim of this study was to assess the feasibility of combining lenalidomide with the standard treatment gemcitabine in pancreatic cancer patients with advanced disease.

Patients and Methods

Eligible patients had locally advanced or metastatic adenocarcinoma of the pancreas. Patients received lenalidomide days 1–21 orally and gemcitabine 1000 mg/m2 intravenously (days 1, 8 and 15), each 28 day cycle. Three cohorts of lenalidomide were examined (Cohort I = 15 mg, Cohort II = 20 mg and Cohort III = 25 mg daily). The maximum tolerated dose (MTD) of lenalidomide given in combination with gemcitabine was defined as the highest dose level at which no more than one out of four (25%) subjects experiences a dose-limiting toxicity (DLT). Patients should also be able to receive daily low molecular weight heparin (LMWH) (e.g. dalteparin 5000 IU s.c. daily) as a prophylactic anticoagulant for venous thromboembolic events (VTEs). Twelve patients (n = 4, n = 3 and n = 5 in cohort I, II and III, respectively) were enrolled in this study.

Results

Median duration of treatment was 11 weeks (range 1–66), and median number of treatment cycles were three (range 1–14). The only DLT was a cardiac failure grade 3 in cohort III. Frequent treatment-related adverse events (AEs) (all grades) included neutropenia, leucopenia and fatigue (83% each, but there was no febrile neutropenia); thrombocytopenia (75%); dermatological toxicity (75%); diarrhea and nausea (42% each); and neuropathy (42%).

Discussion

This phase I study demonstrates the feasibility of the combination of lenalidomide and gemcitabine as first-line treatment in patients with advanced pancreatic cancer. The tolerability profile demonstrated in the dose escalation schedule of lenalidomide suggests the dosing of lenalidomide to be 25 mg daily on days 1–21 with standard dosing of gemcitabine and merits further evaluation in a phase II trial.

Trial Registration

ClinicalTrials.gov NCT01547260

Effect of NF-κB inhibition on chemoresistance in biliary-pancreatic cancer

Biliary cancer and pancreatic cancer are considered to be difficult diseases to cure. Although complete resection provides the only means of curing these cancers, the rate of resectability is not high. Therefore, chemotherapy is often selected in patients with advanced unresectable biliary-pancreatic cancer. Many combination chemotherapy regimens have been applied in clinical trials. However, the survival time is not satisfactory. On the other hand, most chemotherapeutic agents induce anti-apoptotic transcriptional factor nuclear factor kappa b (NF-κB) activation, and agent-induced NF-κB activation is deeply involved in the onset of chemoresistance. Recently, novel approaches to potentiating chemosensitivity in cases of biliary-pancreatic cancer using NF-κB inhibitors with cytotoxic agents have been reported, most of which comprise translational research, although some clinical trials have also been conducted. Nevertheless, to date, there is no breakthrough chemotherapy regimen for these diseases. As some reports show promising data, combination chemotherapy consisting of a NF-κB inhibitor with chemotherapeutic agents seems to improve chemosensitivity and prolong the survival time of biliary-pancreatic cancer patients.

A sensitive and robust HPLC assay with fluorescence detection for the quantification of pomalidomide in human plasma for pharmacokinetic analyses

Pomalidomide is a second generation IMiD (immunomodulatory agent) that has recently been granted approval by the Food and Drug Administration for treatment of relapsed multiple myeloma after prior treatment with two antimyeloma agents, including lenalidomide and bortezomib. A simple and robust HPLC assay with fluorescence detection for pomalidomide over the range of 1-500ng/mL has been developed for application to pharmacokinetic studies in ongoing clinical trials in various other malignancies. A liquid-liquid extraction from human plasma alone or pre-stabilized with 0.1% HCl was performed, using propyl paraben as the internal standard. From plasma either pre-stabilized with 0.1% HCl or not, the assay was shown to be selective, sensitive, accurate, precise, and have minimal matrix effects (<20%). Pomalidomide was stable in plasma through 4 freeze-thaw cycles (<12% change), in plasma at room temperature for up to 2h for samples not pre-stabilized with 0.1% HCl and up to 8h in samples pre-stabilized with 0.1% HCl, 24h post-preparation at 4°C (<2% change), and showed excellent extraction recovery (∼90%). This is the first reported description of the freeze/thaw and plasma stability of pomalidomide in plasma either pre-stabilized with 0.1% HCl or not. The information presented in this manuscript is important when performing pharmacokinetic analyses. The method was used to analyze clinical pharmacokinetics samples obtained after a 5mg oral dose of pomalidomide. This relatively simple HPLC-FL assay allows a broader range of laboratories to measure pomalidomide for application to clinical pharmacokinetics.

Sensitive liquid chromatography/mass spectrometry methods for quantification of pomalidomide in mouse plasma and brain tissue

Pomalidomide was recently approved by the United States Food and Drug Administration for the treatment of patients with relapsed or refractory multiple myeloma who have received at least two prior therapies. As pomalidomide is increasingly evaluated in other diseases and animal disease models, this paper presents development and validation of a sensitive liquid chromatography tandem mass spectrometry assay for quantification of pomalidomide in mouse plasma and brain tissue to fill a gap in published preclinical pharmacokinetic and analytical data with this agent. After acetonitrile protein precipitation, pomalidomide and internal standard, hesperitin, were separated with reverse phase chromatography on a C-18 column with a gradient mobile phase of water and acetonitrile with 0.1% fomic acid. Positive atmospheric pressure chemical ionization mass spectrometry with selected reaction monitoring mode was applied to achieve 0.3-3000nM (0.082-819.73ng/mL) linear range in mouse plasma and 0.6-6000pmol/g in brain tissue. The within- and between-batch accuracy and precision were less than 15% for both plasma and brain tissue. The method was applied to measure pomalidomide concentrations in plasma and brain tissue in a pilot mouse pharmacokinetic study with an intravenous dose of 0.5mg/kg. This assay can be applied for thorough characterization of pomalidomide pharmacokinetics and tissue distribution in mice.

Molecularly targeted therapies in metastatic pancreatic cancer: a systematic review

Pancreatic cancer is the fourth leading cause of cancer-related death. Most patients present with an advanced stage of disease that has a dismal outcome, with a median survival of approximately 6 months. Evidently, there is a clear need for the development of new agents with novel mechanisms of action in this disease. A number of biological agents modulating different signal transduction pathways are currently in clinical development, inhibiting angiogenesis and targeting epidermal growth factor receptor, cell cycle, matrix metalloproteinases, cyclooxygenase-2, mammalian target of rapamycin, or proteasome. This is the first systematic review of the literature to synthesize all available data coming from trials and evaluate the efficacy and safety of molecular targeted drugs in unresectable and metastatic pancreatic cancer. However, it should be stressed that although multiple agents have been tested, only 9 phase 3 trials have been conducted and one agent (erlotinib) has been approved by the Food and Drug Administration for use in clinical practice. As knowledge accumulates on the molecular mechanisms underlying carcinogenesis in the pancreas, the anticipated development and assessment of molecularly targeted agents may offer a promising perspective for a disease which, to date, remains incurable.

Lenalidomide in combination with gemcitabine as first-line treatment for patients with metastatic carcinoma of the pancreas: a Sarah Cannon Research Institute phase II trial

OBJECTIVES

To evaluate the 6-mo overall survival, safety and tolerability of lenalidomide in combination with standard gemcitabine as first-line treatment for patients with metastatic pancreatic cancer.

METHODS

Eligibility included: previously untreated metastatic adenocarcinoma of the pancreas with metastases incurable by surgery/radiation therapy; ECOG PS 0-2; adequate organ function; prophylactic anticoagulation for venous thromboembolic events (VTEs). Patients received lenalidomide 25 mg PO (days 1-21) and gemcitabine 1,000 mg/m ( 2) IV (days 1, 8 and 15) each 28-day cycle, with response evaluations every eight weeks.

RESULTS

Between 5/2009-4/2010, 72 patients (median age 64 years; 68% male; 42% ECOG PS 0) were enrolled in this multicenter, community-based study. Six-month OS was 37% (95% CI 26-48%). Median PFS and OS were 2.3 (95% CI 1.9-3.5) and 4.7 (95% CI 3.4-5.7) months, respectively. Eight partial responses (11%) were documented. Thirty-nine patients (54%) experienced thrombocytopenia (2 patients, 3% grade 4). Hematologic toxicities resulted in dose modifications for the majority of patients. Twenty patients (28%) developed VTEs during treatment.

CONCLUSIONS

The observed 6-month OS (37%) of lenalidomide with gemcitabine does not suggest improvement compared with historical results with gemcitabine alone. Toxicities and dose modifications likely limited dose intensity. Further development of this regimen in pancreas cancer is not recommended.

The 'N-factors' in pancreatic cancer: functional relevance of NF-κB, NFAT and Nrf2 in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) represents one of the deadliest malignancies, with an overall life expectancy of 6 months. Despite considerable advances in the understanding of the molecular mechanisms involved in the carcinogenesis of PDAC, the outcome of the disease was not significantly improved over the last 20 years. Although some achievements in molecular-targeted therapies have been made (that is, targeting the epidermal growth factor receptor by erlotinib), which already entered clinical settings, and despite the promising outcome of the FOLFIRINOX trial, there is an urgent need for improvement of the chemotherapy in this disease. A plethora of molecular alterations are thought to be responsible for the profound chemoresistance, including mutations in oncogenes and tumor suppressors. Besides these classical hallmarks of cancer, the constitutive or inducible activity of transcription factor pathways are characteristic changes in PDAC. Recently, three transcription factors-nuclear factor-κB (NF-κB), nuclear factor of activated T cells (NFAT) and nuclear factor-E2-related factor-2 (Nrf2)-have been shown to be crucial for tumor development and chemoresistance in pancreatic cancer. These transcription factors are key regulators of a variety of genes involved in nearly all aspects of tumorigenesis and resistance against chemotherapeutics and death receptor ligands. Furthermore, the pathways of NF-κB, NFAT and Nrf2 are functional, interacting on several regulatory steps, and, especially, natural compounds such as curcumin interfere with more than one pathway. Thus, targeting these pathways by established inhibitors or new drugs might have great potential to improve the outcome of PDAC patients, most likely in combination with established anticancer drugs. In this article, we summarize recent progress in the characterization of these transcription-factor pathways and their role in PDAC and therapy resistance. We also discuss future concepts for the treatment of PDAC relying on these pathways.

Overcoming nucleoside analog chemoresistance of pancreatic cancer: a therapeutic challenge

Clinical refractoriness to nucleoside analogs (e.g., gemcitabine, capecitabine) is a major scientific problem and is one of the main reasons underlying the extremely poor prognostic state of pancreatic cancer. The drugs' effects are suboptimal partly due to cellular mechanisms limiting their transport, activation, and overall efficacy. Nonetheless, novel therapeutic approaches are presently under study to circumvent nucleoside analog resistance in pancreatic cancer. With these new approaches come additional challenges to be addressed. This review describes the determinants of chemoresistance in the gemcitabine cytotoxicity pathways, provides an overview of investigational approaches for overcoming chemoresistance, and discusses new challenges presented. Understanding the future directions of the field may assist in the successful development of novel treatment strategies for enhancing chemotherapeutic efficacy in pancreatic cancer.

The application and biology of immunomodulatory drugs (IMiDs) in cancer

Immunomodulatory drugs (IMiDs) have been used in hematologic malignancies for the last decade. However, the mechanism of action of IMiDs is largely unknown. Here we provide a comprehensive overview of pivotal studies, recent advances in the application of IMiDs in cancer as well as their effects on hematopoietic stem cells including the risk of secondary malignancies. IMiDs have a well-established role as first-line therapy for patients with newly diagnosed and relapsed/refractory multiple myeloma (MM). Variant combinations of IMiDs with other chemotherapy reagents show promising outcomes in MM. Recent concerns on increased rate of secondary cancer in MM patients treated with maintenance lenalidomide were raised. But analysis of maintenance studies showed that the benefit of maintenance outweighs the risk of secondary cancers in MM. IMiDs also show efficacy in myelodysplastic syndrome (MDS)/acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), Non-Hodgkin's lymphoma (NHL) and myelofibrosis (MF), but not in solid tumors. The major adverse effects are venous thromboembolism, neuropathy and cytopenias. IMiDs induce expansion and self-renewal of CD34+ hematopoietic progenitors and inhibit lineage maturation/differentiation by affecting critical transcription factors which might contribute to myelosuppression effect of IMiDs.

Update on immunomodulatory drugs (IMiDs) in hematologic and solid malignancies

INTRODUCTION

Thalidomide and its analogs [small molecule immunomodulatory drugs (IMiDs®)] are among the most successful new therapeutic agents of recent years. Thalidomide is now an integral part of multiple myeloma (MM) therapy. Lenalidomide has been approved for the treatment of patients with relapsed MM and 5q-myelodysplastic syndromes (MDS). Currently, more than 400 clinical trials are evaluating the activity of lenalidomide, alone or in combination with other conventional or novel therapies, in newly diagnosed MM and 5q-MDS. Based on their broad range of actions within the tumor microenvironment, IMiDs are currently also evaluated in a wide variety of additional hematologic and solid malignancies.

AREAS COVERED

This paper reviews the historic development of thalidomide and its derivatives and presents novel insights into their mode of action. Moreover, it discusses up-to-date clinical trials investigating IMiDs and potential future research and therapeutic perspectives in MM and other malignancies.

EXPERT OPINION

Although IMiDs have emerged as powerful agents for the treatment of hematologic and solid tumors, more preclinical and clinical studies are urgently needed both to increase our knowledge of their mechanisms of action, and to optimize their clinical use, in order to further improve the patient's quality of life and survival.

Molecular targeted approaches for treatment of pancreatic cancer

Human pancreatic cancer remains a highly malignant disease with almost similar incidence and mortality despite extensive research. Many targeted therapies are under development. However, clinical investigation showed that single targeted therapies and most combined therapies were not able to improve the prognosis of this disease, even though some of these therapies had excellent anti-tumor effects in pre-clinical models. Cross-talk between cell proliferation signaling pathways may be an important phenomenon in pancreatic cancer, which may result in cancer cell survival even though some pathways are blocked by targeted therapy. Pancreatic cancer may possess different characteristics and targets in different stages of pathogenesis, maintenance and metastasis. Sensitivity to therapy may also vary for cancer cells at different stages. The unique pancreatic cancer structure with abundant stroma creates a tumor microenvironment with hypoxia and low blood perfusion rate, which prevents drug delivery to cancer cells. In this review, the most commonly investigated targeted therapies in pancreatic cancer treatment are discussed. However, how to combine these targeted therapies and/or combine them with chemotherapy to improve the survival rate of pancreatic cancer is still a challenge. Genomic and proteomic studies using pancreatic cancer samples obtained from either biopsy or surgery are recommended to individualize tumor characters and to perform drug sensitivity study in order to design a tailored therapy with minimal side effects. These studies may help to further investigate tumor pathogenesis, maintenance and metastasis to create cellular expression profiles at different stages. Integration of the information obtained needs to be performed from multiple levels and dimensions in order to develop a successful targeted therapy.