Phase II and coagulation cascade biomarker study of bevacizumab with or without docetaxel in patients with previously treated metastatic pancreatic adenocarcinoma

Chemotherapy and radiotherapy for advanced pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) is a lethal disease with few effective treatment options. Many anti-cancer therapies have been tested in the locally advanced and metastatic setting, with mixed results. This review synthesises all the randomised data available to help better inform patient and clinician decision-making. It updates the previous version of the review, published in 2018.

OBJECTIVES

To assess the effects of chemotherapy, radiotherapy, or both on overall survival, severe or life-threatening adverse events, and quality of life in people undergoing first-line treatment of advanced pancreatic cancer.

SEARCH METHODS

We searched for published and unpublished studies in CENTRAL, MEDLINE, Embase, and CANCERLIT, and handsearched various sources for additional studies. The latest search dates were in March and July 2023.

SELECTION CRITERIA

We included randomised controlled trials comparing chemotherapy, radiotherapy, or both with another intervention or best supportive care. Participants were required to have locally advanced, unresectable pancreatic cancer or metastatic pancreatic cancer not amenable to curative intent treatment. Histological confirmation was required. Trials were required to report overall survival.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 75 studies in the review and 51 in the meta-analysis (11,333 participants). We divided the studies into seven categories: any anti-cancer treatment versus best supportive care; various chemotherapy types versus gemcitabine; gemcitabine-based combinations versus gemcitabine alone; various chemotherapy combinations versus gemcitabine plus nab-paclitaxel; fluoropyrimidine-based studies; miscellaneous studies; and radiotherapy studies. In general, the included studies were at low risk for random sequence generation, detection bias, attrition bias, and reporting bias, at unclear risk for allocation concealment, and high risk for performance bias. Compared to best supportive care, chemotherapy likely results in little to no difference in overall survival (OS) (hazard ratio (HR) 1.08, 95% confidence interval (CI) 0.88 to 1.33; absolute risk of death at 12 months of 971 per 1000 versus 962 per 1000; 4 studies, 298 participants; moderate-certainty evidence). The adverse effects of chemotherapy and impacts on quality of life (QoL) were uncertain. Many of the chemotherapy regimens were outdated. Eight studies compared non-gemcitabine-based chemotherapy regimens to gemcitabine. These showed that 5-fluorouracil (5FU) likely reduces OS (HR 1.69, 95% CI 1.26 to 2.27; risk of death at 12 months of 914 per 1000 versus 767 per 1000; 1 study, 126 participants; moderate certainty), and grade 3/4 adverse events (QoL not reported). Fixed dose rate gemcitabine likely improves OS (HR 0.79, 95% CI 0.66 to 0.94; risk of death at 12 months of 683 per 1000 versus 767 per 1000; 2 studies, 644 participants; moderate certainty), and likely increase grade 3/4 adverse events (QoL not reported). FOLFIRINOX improves OS (HR 0.51, 95% CI 0.43 to 0.60; risk of death at 12 months of 524 per 1000 versus 767 per 1000; P < 0.001; 2 studies, 652 participants; high certainty), and delays deterioration in QoL, but increases grade 3/4 adverse events. Twenty-eight studies compared gemcitabine-based combinations to gemcitabine. Gemcitabine plus platinum may result in little to no difference in OS (HR 0.94, 95% CI 0.81 to 1.08; risk of death at 12 months of 745 per 1000 versus 767 per 1000; 6 studies, 1140 participants; low certainty), may increase grade 3/4 adverse events, and likely worsens QoL. Gemcitabine plus fluoropyrimidine improves OS (HR 0.88, 95% CI 0.81 to 0.95; risk of death at 12 months of 722 per 1000 versus 767 per 1000; 10 studies, 2718 participants; high certainty), likely increases grade 3/4 adverse events, and likely improves QoL. Gemcitabine plus topoisomerase inhibitors result in little to no difference in OS (HR 1.01, 95% CI 0.87 to 1.16; risk of death at 12 months of 770 per 1000 versus 767 per 1000; 3 studies, 839 participants; high certainty), likely increases grade 3/4 adverse events, and likely does not alter QoL. Gemcitabine plus taxane result in a large improvement in OS (HR 0.71, 95% CI 0.62 to 0.81; risk of death at 12 months of 644 per 1000 versus 767 per 1000; 2 studies, 986 participants; high certainty), and likely increases grade 3/4 adverse events and improves QoL. Nine studies compared chemotherapy combinations to gemcitabine plus nab-paclitaxel. Fluoropyrimidine-based combination regimens improve OS (HR 0.79, 95% CI 0.70 to 0.89; risk of death at 12 months of 542 per 1000 versus 628 per 1000; 6 studies, 1285 participants; high certainty). The treatment arms had distinct toxicity profiles, and there was little to no difference in QoL. Alternative schedules of gemcitabine plus nab-paclitaxel likely result in little to no difference in OS (HR 1.10, 95% CI 0.82 to 1.47; risk of death at 12 months of 663 per 1000 versus 628 per 1000; 2 studies, 367 participants; moderate certainty) or QoL, but may increase grade 3/4 adverse events. Four studies compared fluoropyrimidine-based combinations to fluoropyrimidines alone, with poor quality evidence. Fluoropyrimidine-based combinations are likely to result in little to no impact on OS (HR 0.84, 95% CI 0.61 to 1.15; risk of death at 12 months of 765 per 1000 versus 704 per 1000; P = 0.27; 4 studies, 491 participants; moderate certainty) versus fluoropyrimidines alone. The evidence suggests that there was little to no difference in grade 3/4 adverse events or QoL between the two groups. We included only one radiotherapy (iodine-125 brachytherapy) study with 165 participants. The evidence is very uncertain about the effect of radiotherapy on outcomes.

AUTHORS' CONCLUSIONS

Combination chemotherapy remains standard of care for metastatic pancreatic cancer. Both FOLFIRINOX and gemcitabine plus a taxane improve OS compared to gemcitabine alone. Furthermore, the evidence suggests that fluoropyrimidine-based combination chemotherapy regimens improve OS compared to gemcitabine plus nab-paclitaxel. The effects of radiotherapy were uncertain as only one low-quality trial was included. Selection of the most appropriate chemotherapy for individuals still remains unpersonalised, with clinicopathological stratification remaining elusive. Biomarker development is essential to assist in rationalising treatment selection for patients.

Exploration of interaction interface of TRKβ/BDNF through fingerprint analysis to disinter potential agonists

Tyrosine Kinase beta (TRKβ), is a type I membrane receptor which plays a major role in various signalling pathways. TRKβ was found to be upregulated in various cancers and contrastingly downregulated in various neurodegenerative disorders. Hitherto, contemporary drug research is oriented towards discovery of TRKβ inhibitors, thus neglecting the development of TRKβ agonists. This research is aimed at identifying FDA approved drugs exhibiting repurposable potential as TRKβ agonists by mapping them with fingerprints of the BDNF/TRKβ interaction interface. Initially, crucial interacting residues were retrieved and a receptor grid was generated around it. TRKβ agonists were retrieved from literature search and a drug library was created for each agonist based on its structural and side effect similarities. Subsequently, molecular docking and dynamics were performed for each library to identify the drugs possessing affinity towards the binding pocket of TRKβ. The study revealed molecular interactions of Perospirone, Droperidol, Urapidil, and Clobenzorex with the crucial amino acids lining the active binding pocket of TRKβ. Subsequent network pharmacological analysis of the above drugs revealed their interactions with key proteins involved in neurotransmitter signalling pathways. Clobenzorex displayed high stability in dynamics simulation and therefore this drug is recommended for further experimental evaluations to attain better mechanistic insights and predict its implications in correcting neuropathological aberrations. This study's focus on the interaction interface between TRKβ and BDNF, combined with the utilization of fingerprint analysis for drug repurposing, contributes to our understanding of neurotrophic signalling and holds potential for identifying new therapeutic options for neurological disorders.

Clinical and Preclinical Targeting of Oncogenic Pathways in PDAC: Targeted Therapeutic Approaches for the Deadliest Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related death worldwide. It is commonly diagnosed in advanced stages and therapeutic interventions are typically constrained to systemic chemotherapy, which yields only modest clinical outcomes. In this review, we examine recent developments in targeted therapy tailored to address distinct molecular pathway alteration required for PDAC. Our review delineates the principal signaling pathways and molecular mechanisms implicated in the initiation and progression of PDAC. Subsequently, we provide an overview of prevailing guidelines, ongoing investigations, and prospective research trajectories related to targeted therapeutic interventions, drawing insights from randomized clinical trials and other pertinent studies. This review focus on a comprehensive examination of preclinical and clinical data substantiating the efficacy of these therapeutic modalities, emphasizing the potential of combinatorial regimens and novel therapies to enhance the quality of life for individuals afflicted with PDAC. Lastly, the review delves into the contemporary application and ongoing research endeavors concerning targeted therapy for PDAC. This synthesis serves to bridge the molecular elucidation of PDAC with its clinical implications, the evolution of innovative therapeutic strategies, and the changing landscape of treatment approaches.

Clinical Evaluation of the Pancreatic Cancer Microenvironment: Opportunities and Challenges

Advances in our understanding of pancreatic ductal adenocarcinoma (PDAC) and its tumor microenvironment (TME) have the potential to transform treatment for the hundreds of thousands of patients who are diagnosed each year. Whereas the clinical assessment of cancer cell genetics has grown increasingly sophisticated and personalized, current protocols to evaluate the TME have lagged, despite evidence that the TME can be heterogeneous within and between patients. Here, we outline current protocols for PDAC diagnosis and management, review novel biomarkers, and highlight potential opportunities and challenges when evaluating the PDAC TME as we prepare to translate emerging TME-directed therapies to the clinic.

Pancreatic Adenocarcinoma Therapeutics Targeting RTK and TGF Beta Receptor

Despite the improved overall survival rates in most cancers, pancreatic cancer remains one of the deadliest cancers in this decade. The rigid microenvironment, which majorly comprises cancer-associated fibroblasts (CAFs), plays an important role in the obstruction of pancreatic cancer therapy. To overcome this predicament, the signaling of receptor tyrosine kinases (RTKs) and TGF beta receptor (TGFβR) in both pancreatic cancer cell and supporting CAF should be considered as the therapeutic target. The activation of receptors has been reported to be aberrant to cell cycle regulation, and signal transduction pathways, such as growth-factor induced proliferation, and can also influence the apoptotic sensitivity of tumor cells. In this article, the regulation of RTKs/TGFβR between pancreatic ductal adenocarcinoma (PDAC) and CAFs, as well as the RTKs/TGFβR inhibitor-based clinical trials on pancreatic cancer are reviewed.

Therapeutic Application of Monoclonal Antibodies in Pancreatic Cancer: Advances, Challenges and Future Opportunities

Pancreatic cancer remains as one of the most aggressive cancer types. In the absence of reliable biomarkers for its early detection and more effective therapeutic interventions, pancreatic cancer is projected to become the second leading cause of cancer death in the Western world in the next decade. Therefore, it is essential to discover novel therapeutic targets and to develop more effective and pancreatic cancer-specific therapeutic agents. To date, 45 monoclonal antibodies (mAbs) have been approved for the treatment of patients with a wide range of cancers; however, none has yet been approved for pancreatic cancer. In this comprehensive review, we discuss the FDA approved anticancer mAb-based drugs, the results of preclinical studies and clinical trials with mAbs in pancreatic cancer and the factors contributing to the poor response to antibody therapy (e.g. tumour heterogeneity, desmoplastic stroma). MAb technology is an excellent tool for studying the complex biology of pancreatic cancer, to discover novel therapeutic targets and to develop various forms of antibody-based therapeutic agents and companion diagnostic tests for the selection of patients who are more likely to benefit from such therapy. These should result in the approval and routine use of antibody-based agents for the treatment of pancreatic cancer patients in the future.

Therapies Targeting the Tumor Stroma and the VEGF/VEGFR Axis in Pancreatic Ductal Adenocarcinoma: a Systematic Review and Meta-Analysis

Abundant tumor stroma is a hallmark of pancreatic ductal adenocarcinoma (PDAC), and is suggested to play a role in the resistance of this deadly disease to systemic treatment. Despite promising results from preclinical studies, clinical trials with therapies targeting the tumor stroma and the vascular endothelial growth factor (VEGF) and its receptor VEGFR yielded conflicting results. With this systematic review and meta-analysis, we aim to summarize the existing evidence in this important field with a special focus on anti-VEGF/VEGFR therapy. A total of 24 clinical studies were included in the qualitative synthesis, and six randomized controlled trials (RCTs) investigating anti-VEGF/VEGFR agents were further included in the quantitative synthesis. The qualitative synthesis revealed a treatment advantage of combined therapy with nab-paclitaxel, while the meta-analysis on anti-VEGF/VEGFR drugs demonstrated marginal improvement of objective response rates and progression-free survival, but not overall survival. Stroma targeting is a promising and rapidly-developing treatment strategy in PDAC. However, novel drugs balancing stroma depletion and modulation are needed.

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.

Angiogenesis in pancreatic cancer: current research status and clinical implications

Pancreatic cancer is one of the most lethal malignancies worldwide. Although the standard of care in pancreatic cancer has improved, prognoses for patients remain poor with a 5-year survival rate of < 5%. Angiogenesis, namely, the formation of new blood vessels from pre-existing vessels, is an important event in tumor growth and hematogenous metastasis. It is a dynamic and complex process involving multiple mechanisms and is regulated by various molecules. Inhibition of angiogenesis has been an established therapeutic strategy for many solid tumors. However, clinical outcomes are far from satisfying for pancreatic cancer patients receiving anti-angiogenic therapies. In this review, we summarize the current status of angiogenesis in pancreatic cancer research and explore the reasons for the poor efficacy of anti-angiogenic therapies, aiming to identify some potential therapeutic targets that may enhance the effectiveness of anti-angiogenic treatments.

Current status and dilemma of second-line treatment in advanced pancreatic cancer: is there a silver lining?

Pancreatic cancer remains one of the most lethal malignant diseases worldwide. The majority of patients present with advanced disease and, therefore, need palliative chemotherapy. Some chemotherapeutic regimens have been well established as first-line therapies and have been shown to increase survival; however, almost all patients with advanced pancreatic cancer will experience disease progression after first-line therapy. Nevertheless, many patients who retain good performance status after initial treatment remain good candidates for additional therapy. Historically, few studies have assessed second-line therapy, with most reports representing small phase II trials with variable findings; however, clinical research for second-line treatment has increased in the past decade, and several randomized controlled trials using different regimens have been published. The current literature shows varying results on treatment efficacy and tolerability. Thus, we reviewed the published data on the use of chemotherapy in the second-line setting for the treatment of advanced pancreatic cancer.

Chemotherapy and radiotherapy for advanced pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) is a highly lethal disease with few effective treatment options. Over the past few decades, many anti-cancer therapies have been tested in the locally advanced and metastatic setting, with mixed results. This review attempts to synthesise all the randomised data available to help better inform patient and clinician decision-making when dealing with this difficult disease.

OBJECTIVES

To assess the effect of chemotherapy, radiotherapy or both for first-line treatment of advanced pancreatic cancer. Our primary outcome was overall survival, while secondary outcomes include progression-free survival, grade 3/4 adverse events, therapy response and quality of life.

SEARCH METHODS

We searched for published and unpublished studies in CENTRAL (searched 14 June 2017), Embase (1980 to 14 June 2017), MEDLINE (1946 to 14 June 2017) and CANCERLIT (1999 to 2002) databases. We also handsearched all relevant conference abstracts published up until 14 June 2017.

SELECTION CRITERIA

All randomised studies assessing overall survival outcomes in patients with advanced pancreatic ductal adenocarcinoma. Chemotherapy and radiotherapy, alone or in combination, were the eligible treatments.

DATA COLLECTION AND ANALYSIS

Two review authors independently analysed studies, and a third settled any disputes. We extracted data on overall survival (OS), progression-free survival (PFS), response rates, adverse events (AEs) and quality of life (QoL), and we assessed risk of bias for each study.

MAIN RESULTS

We included 42 studies addressing chemotherapy in 9463 patients with advanced pancreatic cancer. We did not identify any eligible studies on radiotherapy.We did not find any benefit for chemotherapy over best supportive care. However, two identified studies did not have sufficient data to be included in the analysis, and many of the chemotherapy regimens studied were outdated.Compared to gemcitabine alone, participants receiving 5FU had worse OS (HR 1.69, 95% CI 1.26 to 2.27, moderate-quality evidence), PFS (HR 1.47, 95% CI 1.12 to 1.92) and QoL. On the other hand, two studies showed FOLFIRINOX was better than gemcitabine for OS (HR 0.51 95% CI 0.43 to 0.60, moderate-quality evidence), PFS (HR 0.46, 95% CI 0.38 to 0.57) and response rates (RR 3.38, 95% CI 2.01 to 5.65), but it increased the rate of side effects. The studies evaluating CO-101, ZD9331 and exatecan did not show benefit or harm when compared with gemcitabine alone.Giving gemcitabine at a fixed dose rate improved OS (HR 0.79, 95% CI 0.66 to 0.94, high-quality evidence) but increased the rate of side effects when compared with bolus dosing.When comparing gemcitabine combinations to gemcitabine alone, gemcitabine plus platinum improved PFS (HR 0.80, 95% CI 0.68 to 0.95) and response rates (RR 1.48, 95% CI 1.11 to 1.98) but not OS (HR 0.94, 95% CI 0.81 to 1.08, low-quality evidence). The rate of side effects increased. Gemcitabine plus fluoropyrimidine improved OS (HR 0.88, 95% CI 0.81 to 0.95), PFS (HR 0.79, 95% CI 0.72 to 0.87) and response rates (RR 1.78, 95% CI 1.29 to 2.47, high-quality evidence), but it also increased side effects. Gemcitabine plus topoisomerase inhibitor did not improve survival outcomes but did increase toxicity. One study demonstrated that gemcitabine plus nab-paclitaxel improved OS (HR 0.72, 95% CI 0.62 to 0.84, high-quality evidence), PFS (HR 0.69, 95% CI 0.58 to 0.82) and response rates (RR 3.29, 95% CI 2.24 to 4.84) but increased side effects. Gemcitabine-containing multi-drug combinations (GEMOXEL or cisplatin/epirubicin/5FU/gemcitabine) improved OS (HR 0.55, 95% CI 0.39 to 0.79, low-quality evidence), PFS (HR 0.43, 95% CI 0.30 to 0.62) and QOL.We did not find any survival advantages when comparing 5FU combinations to 5FU alone.

AUTHORS' CONCLUSIONS

Combination chemotherapy has recently overtaken the long-standing gemcitabine as the standard of care. FOLFIRINOX and gemcitabine plus nab-paclitaxel are highly efficacious, but our analysis shows that other combination regimens also offer a benefit. Selection of the most appropriate chemotherapy for individual patients still remains difficult, with clinicopathological stratification remaining elusive. Biomarker development is essential to help rationalise treatment selection for patients.

Inhibition of Endothelial SCUBE2 (Signal Peptide-CUB-EGF Domain-Containing Protein 2), a Novel VEGFR2 (Vascular Endothelial Growth Factor Receptor 2) Coreceptor, Suppresses Tumor Angiogenesis

OBJECTIVE

SCUBE2 (signal peptide-CUB-EGF domain-containing protein 2), expressed on the endothelial cell surface, functions as a novel coreceptor for VEGFR2 (vascular endothelial growth factor receptor 2) and enhances VEGF-induced signaling in adult angiogenesis. However, whether SCUBE2 plays a role in pathological angiogenesis and whether anti-SCUBE2 antibody is an effective strategy for blocking tumor angiogenesis remain unknown. The aim of this study was to investigate the pathological role and targeting therapy of SCUBE2 in tumor vasculature.

APPROACH AND RESULTS

Immunohistochemistry revealed that SCUBE2 is highly expressed in endothelial cells of numerous carcinomas. Genetic endothelial cell knockout of SCUBE2 and pharmacological inhibition with the anti-SCUBE2 monoclonal antibody SP.B1 significantly reduced xenograft tumor growth, decreased tumor vascular density, increased apoptosis, and decreased the proliferation of tumor cells. Mechanistic studies revealed that SP.B1 binds to SCUBE2 and induces its internalization for lysosomal degradation, thereby reducing its cell surface level and inhibiting the binding of and downstream signaling of VEGF, including VEGFR2 phosphorylation and AKT/MAPK (mitogen-activated protein kinase) activation. Importantly, dual combination therapy with anti-SCUBE2 monoclonal antibody and anti-VEGF antibody or chemotherapy was more effective than single-agent therapy.

CONCLUSIONS

Endothelial cell surface SCUBE2 is a VEGFR2 coreceptor essential for pathological tumor angiogenesis, and anti-SCUBE2 monoclonal antibody acting as an internalization inducer may provide a potent combination therapy for tumor angiogenesis.

Targeted delivery of chemotherapy using HSP90 inhibitor drug conjugates is highly active against pancreatic cancer models

The lack of effective treatment modalities is a major problem in pancreatic cancer (PCa), a devastating malignancy that is nearly universally driven by the “undruggable” KRAS and TP53 cancer genes. Poor tumor tissue penetration is the major source of resistance in pancreatic cancer where chemotherapy is the mainstay of treatment. In this study we exploited the selective tumor-targeting properties of the heat shock 90 protein inhibitors as the vehicle for drug delivery to pancreatic tumor tissues. STA-12-8666 is a novel esterase-cleavable conjugate of an HSP90i and a topoisomerase I inhibitor, SN-38. STA-12-8666 selectively binds activated HSP90 and releases its cytotoxic payload resulting in drug accumulation in pancreatic cancer cells in vivo. We investigated the preclinical activity of STA-12-8666 in patient derived xenograft and genetic models of pancreatic cancer.

Treatment with STA-12-8666 of the KPC mice (knock-in alleles of LSL-Kras^G12D, Tp53^fl/fl and Pdx1-Cre transgene) at the advanced stages of pancreatic tumors doubled their survival (49 days vs. 74 days, p=0.008). STA-12-8666 also demonstrated dramatically superior activity in comparison to equimolar doses of irinotecan against 5 patient-derived pancreatic adenocarcinoma xenografts with prolonged remissions in some tumors. Analysis of activity of STA-12-8666 against tumor tissues and matched cell lines demonstrated prolonged accumulation and release of cytotoxic payload in the tumor leading to DNA damage response and cell cycle arrest.

Our results provide a proof-of-principle validation that HSP90i-based drug conjugates can overcome the notorious treatment resistance by utilizing the inherently high affinity of pancreatic cancer cells to HSP90 antagonists.

Second-line chemotherapy for advanced pancreatic cancer: Which is the best option?

Despite recent biological insight and therapeutic advances, the prognosis of advanced pancreatic cancer still remains poor. For more than 15 years, gemcitabine monotherapy has been the cornerstone of first-line treatment. Recently, prospective randomized trials have shown that novel upfront combination regimens tested in prospective randomized trials have resulted in improved patients' outcome increasing the proportion of putative candidate to second-line therapy. There is no definite standard of care after disease progression. A novel formulation in which irinotecan is encapsulated into liposomal-based nanoparticles may increase the efficacy of the drug without incrementing its toxicity. NAPOLI-1 was the first randomized trial to compare nanoliposomal irinotecan and fluorouracil-leucovorin (5-FU/LV) to 5-FU/LV alone after a gemcitabine-based chemotherapy. This review focuses on the current data for the management of second-line treatment for metastatic pancreatic adenocarcinoma, presents the most interesting ongoing clinical trials and illustrates the biologically-driven future options beyond disease progression.

Tackling pancreatic cancer with metronomic chemotherapy

Pancreatic tumours, the majority of which arise from the exocrine pancreas, have recently shown an increasing incidence in western countries. Over the past few years more and more new selective molecules directed against specific cellular targets have become available for cancer therapy, leading to significant improvements. However, despite such advances in therapy, prognosis of pancreatic cancer remains disappointing. Metronomic chemotherapy (MCT), which consists in the administration of continuous, low-dose anticancer drugs, has demonstrated the ability to suppress tumour growth. Thus, it may provide an additional therapeutic opportunity for counteracting the progression of the tumour. Here we discuss evidence arising from preclinical and clinical studies regarding the use of MCT in pancreatic cancer. Good results have generally been achieved in preclinical studies, particularly when MCT was combined with standard dose chemotherapy or antinflammatory, antiangiogenic and immunostimolatory agents. The few available clinical experiences, which mainly refer to retrospective data, have reported good tolerability though mild activity of metronomic schedules. Further studies are therefore awaited to confirm both preclinical findings and the preliminary clinical data.

Screening of Conditionally Reprogrammed Patient-Derived Carcinoma Cells Identifies ERCC3-MYC Interactions as a Target in Pancreatic Cancer

PURPOSE

Even when diagnosed prior to metastasis, pancreatic ductal adenocarcinoma (PDAC) is a devastating malignancy with almost 90% lethality, emphasizing the need for new therapies optimally targeting the tumors of individual patients.

EXPERIMENTAL DESIGN

We first developed a panel of new physiologic models for study of PDAC, expanding surgical PDAC tumor samples in culture using short-term culture and conditional reprogramming with the Rho kinase inhibitor Y-27632, and creating matched patient-derived xenografts (PDX). These were evaluated for sensitivity to a large panel of clinical agents, and promising leads further evaluated mechanistically.

RESULTS

Only a small minority of tested agents was cytotoxic in minimally passaged PDAC cultures in vitro Drugs interfering with protein turnover and transcription were among most cytotoxic. Among transcriptional repressors, triptolide, a covalent inhibitor of ERCC3, was most consistently effective in vitro and in vivo causing prolonged complete regression in multiple PDX models resistant to standard PDAC therapies. Importantly, triptolide showed superior activity in MYC-amplified PDX models and elicited rapid and profound depletion of the oncoprotein MYC, a transcriptional regulator. Expression of ERCC3 and MYC was interdependent in PDACs, and acquired resistance to triptolide depended on elevated ERCC3 and MYC expression. The Cancer Genome Atlas analysis indicates ERCC3 expression predicts poor prognosis, particularly in CDKN2A-null, highly proliferative tumors.

CONCLUSIONS

This provides initial preclinical evidence for an essential role of MYC-ERCC3 interactions in PDAC, and suggests a new mechanistic approach for disruption of critical survival signaling in MYC-dependent cancers. Clin Cancer Res; 22(24); 6153-63. ©2016 AACR.

Efficacy and safety profile of nab-paclitaxel plus gemcitabine in patients with metastatic pancreatic cancer treated to disease progression: a subanalysis from a phase 3 trial (MPACT)

Background

The phase 3 MPACT trial in patients with metastatic pancreatic cancer demonstrated superior efficacy of nab-paclitaxel (nab-P) + gemcitabine (Gem) vs Gem monotherapy for all endpoints examined including overall survival, the primary endpoint. In the MPACT trial, patients were treated until progressive disease (PD) or unacceptable toxicity. The current exploratory analysis investigated outcomes of patients from the MPACT trial who were treated until PD, in order to understand how to maximize treatment benefit from nab-P + Gem.

Methods

The trial design has been described in detail previously. Progressive disease was determined by the investigator on the basis of radiological imaging.

Results

Among patients who were treated until PD, overall survival was significantly longer for those who received nab-P + Gem vs Gem (median, 9.8 vs 7.5 months; P < 0.001). Independently assessed progression-free survival and overall response rate were significantly greater among patients in the treatment-to-PD cohort who received nab-P + Gem compared with Gem (P < 0.001 for each). Although not compared statistically, patients who were treated until PD received greater treatment exposure and experienced more favourable efficacy than the intent-to-treat population of the MPACT trial. Among patients who were treated with nab-P + Gem until PD, > 50 % went on to receive a subsequent therapy. The safety profile for patients treated until PD was similar to what was reported in the overall MPACT trial.

Conclusion

The nab-P + Gem regimen is an active first-line treatment option; most patients were treated until PD, and this exposure was associated with improved efficacy outcomes. Prolonged first-line treatment exposure and ability to receive subsequent therapies likely contributed to the improved survival among these patients. Our data highlight the importance of managing adverse events and indicate that patients should be treated until PD when possible.

Trial registration

ClinicalTrials.gov NCT00844649 (MPACT trial); Registration date of this prospective phase III trial: February 13, 2009; current exploratory subanalysis was conducted retrospectively.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2798-8) contains supplementary material, which is available to authorized users.

Pancreatic cancer: New hopes after first line treatment

Pancreatic cancer is the fourth leading cause of cancer-related death worldwide. Extensive research has yielded advances in first-line treatment strategies, but there is no standardized second-line therapy. In this review, we examine the literature trying to establish a possible therapeutic algorithm.

Overview of pre-clinical and clinical studies targeting angiogenesis in pancreatic ductal adenocarcinoma

The importance of angiogenesis in pancreatic ductal adenocarcinoma (PDAC) and its therapeutic potential have been explored in both pre-clinical and clinical studies. Human PDACs overexpress a number of angiogenic factors and their cognate high-affinity receptors, and anti-angiogenic agents reduce tumor volume, metastasis, and microvessel density (MVD), and improve survival in subcutaneous and orthotopic pre-clinical models. Nonetheless, clinical trials using anti-angiogenic therapy have been overwhelmingly unsuccessful. This review will focus on these pre-clinical and clinical studies, the potential reasons for failure in the clinical setting, and ways these shortcomings could be addressed in future investigations of angiogenic mechanisms in PDAC.

Second-line treatment in inoperable pancreatic adenocarcinoma: A systematic review and synthesis of all clinical trials

There remains uncertainty regarding the optimal second-line chemotherapy in advanced pancreatic ductal adenocarcinoma (PDAC). The current recommendation of 5-fluorouracil and oxaliplatin may not be relevant in current practice, as FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan and oxaliplatin) has become a more popular first line therapy in fit patients. The majority of studies in this setting are single-arm Phase II trials with significant heterogeneity of patient populations, treatments and outcomes. In this review, we sought to systematically review and synthesise all prospective data available for the second-line treatment of advanced PDAC.

Recent advances for the treatment of pancreatic and biliary tract cancer after first-line treatment failure

Here, we evaluate clinical trials on chemotherapy for patients with pancreatic or biliary tract cancer after first-line treatment failure. Clinical trials on conventional and innovative medical treatments for progressive pancreatic and biliary cancer were analyzed. Metronomic chemotherapy, which consists of the administration of continuative low-dose of anticancer drugs, was also considered. A significant extension of overall survival was achieved with second-line, regimens in patients with gemcitabine-refractory pancreatic cancer. Moreover, many Phase II studies, including chemotherapy and target molecules and immunotherapy, have reported promising results, in both pancreatic and biliary cancer. However, data in these patients' setting are very heterogeneous, and only few randomized studies are available.

Specificity delivers: therapeutic role of tumor antigen-specific antibodies in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDA) is among the most deadly cancers with less than 5% of the patients living beyond 5 years post-diagnosis. Lack of early diagnostic biomarkers and resistance to current therapies help explain these disappointing numbers. Thus, more effective and better-targeted therapies are needed quickly. Monoclonal antibodies offer an attractive alternative targeted therapy option for PDA because they are highly specific and potent. However, currently available monoclonal antibody therapies for PDA are still in their infancy with a low success rate and low likelihood of being approved. The challenges faced by these therapies include the following: lack of predictive and response biomarkers, unfavorable safety profiles, expression of targets not restricted to the cancer cells, flawed preclinical model systems, drug resistance, and PDA's complex nature. Additionally, discovery of novel PDA-specific antigen targets, present on the cell surface or in the extracellular matrix, is needed. Predictive and response markers also need to be determined for PDA patient subgroups so that the most appropriate effective therapy can be delivered. Serologic approaches, recombinant antibody-producing technologies, and advances in antibody engineering techniques will help to identify these predictive biomarkers and aid in the development of new therapeutic antibodies. A combinatorial approach simultaneously targeting antigens on the PDA cell, stroma, and immunosuppressive cells should be employed.

Second-line oxaliplatin, folinic acid, and fluorouracil versus folinic acid and fluorouracil alone for gemcitabine-refractory pancreatic cancer: outcomes from the CONKO-003 trial

PURPOSE

To assess the efficacy of a second-line regimen of oxaliplatin and folinic acid-modulated fluorouracil in patients with advanced pancreatic cancer who have experienced progression while receiving gemcitabine monotherapy.

PATIENTS AND METHODS

A randomized, open-label, phase III study was conducted in 16 institutions throughout Germany. Recruitment ran from January 2004 until May 2007, and the last follow-up concluded in December 2012. Overall, 168 patients age 18 years or older who experienced disease progression during first-line gemcitabine therapy were randomly assigned to folinic acid and fluorouracil (FF) or oxaliplatin and FF (OFF). Patients were stratified according to the presence of metastases, duration of first-line therapy, and Karnofsky performance status.

RESULTS

Median follow-up was 54.1 months, and 160 patients were eligible for the primary analysis. The median overall survival in the OFF group (5.9 months; 95% CI, 4.1 to 7.4) versus the FF group (3.3 months; 95% CI, 2.7 to 4.0) was significantly improved (hazard ratio [HR], 0.66; 95% CI, 0.48 to 0.91; log-rank P = .010). Time to progression with OFF (2.9 months; 95% CI, 2.4 to 3.2) versus FF (2.0 months; 95% CI, 1.6 to 2.3) was significantly extended also (HR, 0.68; 95% CI, 0.50 to 0.94; log-rank P = .019). Rates of adverse events were similar between treatment arms, with the exception of grades 1 to 2 neurotoxicity, which were reported in 29 patients (38.2%) and six patients (7.1%) in the OFF and FF groups, respectively (P < .001).

CONCLUSION

Second-line OFF significantly extended the duration of overall survival when compared with FF alone in patients with advanced gemcitabine-refractory pancreatic cancer.

Beyond first-line chemotherapy for advanced pancreatic cancer: an expanding array of therapeutic options?

While an increasing number of therapeutic options are now available for the first-line treatment of locally advanced or metastatic pancreatic cancer, the optimal choice for treatment in the second-line setting and beyond is less well defined. A variety of cytotoxic agents, either alone or in combination, have been evaluated, although primarily in the context of small single-arm or retrospective studies. Most regimens have been associated with median progression-free survival rates in the range of 2-4 mo and overall survival rates between 4-8 mo, highlighting the very poor prognosis of patients who are candidates for such treatment. Targeted therapies studied in this chemotherapy-refractory setting, meanwhile, have produced even worse efficacy results. In the current article, we review the clinical evidence for treatment of refractory disease, primarily in patients who have progressed on front-line gemcitabine-based chemotherapy. In the process, we highlight the limitations of the available data to date as well as some of the challenges in designing appropriate clinical trials in this salvage setting, including how to select an appropriate control arm given the absence of a well-established reference standard, and the importance of incorporating predictive biomarkers and quality of life measures whenever possible into study design.

Second-line treatment in advanced pancreatic cancer: a comprehensive analysis of published clinical trials

BACKGROUND

There is currently no standard of care for the second-line treatment of advanced pancreatic cancer. The aim of this analysis was to compare the different therapeutic approaches in this setting.

METHODS

We carried out a systematic analysis of second-line studies in advanced pancreatic cancer that have progressed on or following gemcitabine and published or presented from 2000 to 2012.

RESULTS

Forty-four clinical trials (t) were identified; of which 34 met the inclusion criteria treating an aggregate total of 1503 patients (n). Patients who received treatments (t: 33; n: 1269) had a median overall survival (OS) of 6 months compared with 2.8 months for patients who received best supportive care only (t: 2; n: 234) (P = 0.013). The gemcitabine and platinum-based combination (t: 5; n: 154) provided a median progression-free survival and OS of 4 and 6 months compared with 1.6 and 5.3 for the rest of the regimens (t: 29; n: 1349) (P = 0.059 and 0.10, respectively) and 2.9 and 5.7 for the combination of 5-fluorouracil and platinum agents (t: 12; n: 450) (P = 0.60 and 0.22, respectively).

CONCLUSION(S)

Although not conclusive, these data showed that the advantage of second-line chemotherapy in pancreatic cancer is very limited and there is a need for more studies.

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.

BIBF 1120 (nintedanib), a triple angiokinase inhibitor, induces hypoxia but not EMT and blocks progression of preclinical models of lung and pancreatic cancer

Signaling from other angiokinases may underlie resistance to VEGF-directed therapy. We evaluated the antitumor and biologic effects of BIBF 1120 (nintedanib), a tyrosine kinase inhibitor that targets VEGF receptor, platelet-derived growth factor receptor, and fibroblast growth factor receptor in preclinical models of lung and pancreatic cancer, including models resistant to VEGF-targeted treatments. In vitro, BIBF 1120 did not show antiproliferative effects, nor did it sensitize tumor cells to chemotherapy. However, in vivo BIBF 1120 inhibited primary tumor growth in all models as a single agent and in combination with standard chemotherapy. Analysis of tumor tissue posttreatment revealed that BIBF 1120 reduced proliferation (phospho-histone 3) and elevated apoptosis (cleaved caspase-3) to a greater extent than chemotherapy alone. Furthermore, BIBF 1120 showed potent antiangiogenic effects, including decreases in microvessel density (CD31), pericyte coverage (NG2), vessel permeability, and perfusion, while increasing hypoxia. Despite the induction of hypoxia, markers of epithelial-to-mesenchymal transition (EMT) were not elevated in BIBF 1120-treated tumors. In summary, BIBF 1120 showed potent antitumor and antiangiogenic activity in preclinical models of lung and pancreatic cancer where it induced hypoxia but not EMT. The absence of EMT induction, which has been implicated in resistance to antiangiogenic therapies, is noteworthy. Together, these results warrant further clinical studies of BIBF 1120.

The pancreas cancer microenvironment

Pancreatic ductal adenocarcinoma (PDA) is a common and lethal malignancy resulting in more than 250,000 deaths per year worldwide. Despite extensive efforts, cytotoxic and targeted therapies have provided only limited efficacy for patients with PDA to date. One contributing factor to the failure of systemic therapies may be the abundant tumor stromal content that is the characteristic of PDA. The PDA stroma, aptly termed the tumor microenvironment, occupies the majority of the tumor mass, and consists of a dynamic assortment of extracellular matrix components and nonneoplastic cells including fibroblastic, vascular, and immune cells. Recent work has revealed that the PDA stroma supports tumor growth and promotes metastasis and simultaneously serves as a physical barrier to drug delivery. Accordingly, methods that alter stromal composition or function, for instance interference with the vasculature via Notch/Hedgehog pathway inhibition or relief of vascular compression by hyaluronidase, are under active investigation. Here, we will review our current understanding of the PDA tumor microenvironment, and highlight opportunities for further exploration that may benefit patients.

Incidence, prognosis, and possible treatment strategies of peritoneal carcinomatosis of pancreatic origin: a population-based study

OBJECTIVES

Peritoneal carcinomatosis (PC) is an important cause of morbidity and mortality among patients with pancreatic cancer. In an era where therapeutic options for PC of multiple origins are emerging, our aim was to provide population-based data on incidence, treatment, and prognosis of PC of pancreatic origin.

METHODS

All patients with a condition diagnosed as nonendocrine pancreatic cancer between 1995 and 2009 in the area of the Eindhoven Cancer Registry were included.

RESULTS

In total, 2924 patients had a diagnosis of pancreatic cancer of which 265 patients (9%) presented with synchronous PC. An increasing trend could be noted in patients treated with chemotherapy in more recent years (11% in 1995-1999 and 22% in 2005-2009; P = 0.060). Median survival in patients presenting with PC was only 6 weeks (95% confidence interval, 5-7 weeks) and did not improve over time, contrasting improvements among patients with nonmetastasized disease (19-30 weeks) and patients with metastasized disease confined to the liver (8-12 weeks).

CONCLUSION

Prognosis of patients with pancreatic cancer presenting with PC remains extremely poor. Treatment options are scarce and, given the magnitude of the problem, efforts should be undertaken to develop effective treatments in experimental and clinical studies.

Progression-free Survival Decreases with Each Subsequent Therapy in Patients Presenting for Phase I Clinical Trials

Background: There is often a finite progression-free interval of time between one systemic therapy and the next when treating patients with advanced cancer. While it appears that progression-free survival (PFS) between systemic therapies tends to get shorter for a number of factors, there has not been a formal evaluation of diverse tumor types in an advanced cancer population treated with commercially-available systemic therapies.

Methods: In an attempt to clarify the relationship between PFS between subsequent systemic therapies, we analyzed the records of 165 advanced cancer patients coming to our clinic for consideration for participation in six different phase I clinical trials requiring detailed and extensive past medical treatment history documentation.

Results: There were 77 men and 65 women meeting inclusion criteria with a median age at diagnosis of 55.3 years (range 9.4-81.6). The most common cancer types were colorectal (13.9%), other gastrointestinal (11.8%), prostate (11.8%). A median of 3 (range 1-11) systemic therapies were received prior to phase I evaluation. There was a significant decrease in PFS in systemic therapy for advanced disease from treatment 1 to treatment 2 to treatment 3 (p = 0.002), as well as, from treatment 1 through treatment 5 (p < 0.001).

Conclusions: In an advanced cancer population of diverse tumor types, we observe a statistically significant decrease in PFS with each successive standard therapy. Identification of new therapies that reverse this trend of decreasing PFS may lead to improved clinical outcomes.

Phase I safety and pharmacokinetic study of bavituximab, a chimeric phosphatidylserine-targeting monoclonal antibody, in patients with advanced solid tumors

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.

Current use and potential role of bevacizumab in the treatment of gastrointestinal cancers

Angiogenesis is essential for cancer growth and metastasis. Vascular endothelial growth factor (VEGF) is a key modulator of angiogenesis. In addition, overexpression of VEGF is correlated with advanced disease and poor prognosis. Bevacizumab, a recombinant humanized anti-VEGF monoclonal antibody, is the first anti-angiogenic agent approved by Food and Drug Administration for use in treatment of human solid cancers. Although bevacizumab has received most attention for first-line treatment of advanced colorectal and nonsmall-cell lung cancer, there is a rapidly growing body of evidence for its efficacy in treatment of a number of other solid tumors. We present the current status and potential use of bevacizumab therapy in gastrointestinal cancers.

Monoclonal antibodies in the treatment of pancreatic cancer

Human pancreatic cancer is a malignant disease with almost equal incidence and mortality. Effective diagnostic and therapeutic strategies are still urgently needed to improve its survival rate. With advances in structural and functional genomics, recent work has focused on targeted molecular therapy using monoclonal antibodies. This review summarizes the target molecules on the tumor cell surface and normal tissue stroma, which are related to pancreatic cancer oncogenesis, tumor growth or resistance to chemotherapy, as well as molecules involved in regulating inflammation and host immunoresponses. Targeted molecules include cell-surface receptors, such as the EGF receptor, HER2, death receptor 5 and IGF-1 receptor. Effects of monoclonal antibodies against these target molecules alone or in combination with chemotherapy, small-molecule signal transduction inhibitors, or radiation therapy are also discussed. Also discussed are the use of toxin or radioisotope conjugates, and information relating to the use of these targeting agents in pancreatic cancer clinical trials. Although targeted molecular therapy with monoclonal antibodies has made some progress in pancreatic cancer treatment, especially in preclinical studies, its clinical application to improve the survival rate of pancreatic cancer patients requires further investigation.