Bevacizumab combined with gemcitabine and capecitabine for advanced pancreatic cancer: a phase II study

Phase II randomised, double-blind study of mFOLFIRINOX plus ramucirumab versus mFOLFIRINOX plus placebo in advanced pancreatic cancer patients (HCRN GI14-198)

BACKGROUND

Vascular endothelial growth factor receptor (VEGFR)-mediated signalling contributes to andgiogenesis and therapy resistance in pancreatic ductal adenocarcinoma (PDAC). Ramucirumab (RAM) is a VEGFR2 monoclonal antibody. We conducted a randomised phase II trial to compare progression-free survival (PFS) between mFOLFIRINOX with or without RAM in first line therapy of metastatic PDAC.

METHODS

This phase II randomised, multi-centre, placebo controlled, double-blinded, trial randomly assigned to recurrent/metastatic PDAC patients to either mFOLFIRINOX/RAM (Arm A) or mFOLFIRINOX/placebo (Arm B). The primary endpoint is PFS at 9 months, and the secondary endpoints include overall survival (OS), response rate and toxicity evaluation.

RESULTS

A total of 86 subjects enrolled, 82 eligible (42 in Arm A versus 40 in Arm B). The mean age was comparable (61.7 versus 63.0, respectively). Majority were White (N = 69) and males (N = 43). The median PFS was 5.6 compared to 6.7 months, for Arm A and B, respectively. At 9 months, the PFS rates were 25.1% and 35.0% for Arms A and B, respectively (p = 0.322). The median OS in Arm A was 10.3 compared to 9.7 months for Arm B (p = 0.094). The disease response rate for Arm A was 17.7% compared to Arm B of 22.6%. FOLFIRINOX/RAM combination was well tolerated.

CONCLUSIONS

The addition of RAM to FOLFIRINOX did not significantly impact PFS or OS. The combination was well tolerated (Funded by Eli Lilly; ClinicalTrials.gov number, NCT02581215).

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.

Regorafenib in patients with refractory metastatic pancreatic cancer: a Phase II study (RESOUND)

Aim: Regorafenib may be active in different cancer types. This Phase II trial included patients with various refractory cancer types treated with regorafenib. Here, we report the results of the pancreatic adenocarcinoma cohort. Methods: The primary end point was progression-free survival (PFS) rate at 8 weeks; further investigation of regorafenib would be warranted with a PFS rate ≥50%. Results: A total of 20 patients were enrolled. The best response was stable disease in four patients (20%). The 8-week PFS rate was 25% with a median PFS of 1.7 months (95% CI: 1.5–2.0). A total of 13 patients (65%) experienced grade 3–4 treatment-related adverse events. Conclusion: The study did not meet its primary end point. Further investigation of regorafenib monotherapy in this setting is not recommended.

Clinical Trial Registration: NCT02307500

Evaluation of Phase II Trial Design in Advanced Pancreatic Cancer

OBJECTIVES

We evaluated how well phase II trials in locally advanced and metastatic pancreatic cancer (LAMPC) meet current recommendations for trial design.

METHODS

We conducted a systematic review of phase II first-line treatment trial for LAMPC. We assessed baseline characteristics, type of comparison, and primary end point to examine adherence to the National Cancer Institute recommendations for trial design.

RESULTS

We identified 148 studies (180 treatment arms, 7505 participants). Forty-seven (32%) studies adhered to none of the 5 evaluated National Cancer Institute recommendations, 62 (42%) followed 1, 31 (21%) followed 2, and 8 (5%) followed 3 recommendations. Studies varied with respect to the proportion of patients with good performance status (range, 0%-80%) and locally advanced disease (range, 14%-100%). Eighty-two (55%) studies concluded that investigational agents should progress to phase III testing; of these, 24 (16%) had documented phase III trials. Three (8%) phase III trials demonstrated clinically meaningful improvements for investigational agents. One of 38 phase II trials that investigated biological investigational agents was enriched for a biomarker.

CONCLUSIONS

Phase II trials do not conform well to current recommendations for trial design in LAMPC.

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.

Treatment-related Hypertension as a Pharmacodynamic Biomarker for the Efficacy of Bevacizumab in Advanced Pancreas Cancer: A Pooled Analysis of 4 Prospective Trials of Gemcitabine-based Therapy With Bevacizumab

PURPOSE

Phase III studies of bevacizumab in advanced pancreas cancer (APCA) demonstrated no improvement in outcome. No validated biomarkers for bevacizumab efficacy exist. We evaluated bevacizumab-related hypertension (B-HTN) as a biomarker in APCA patients in a pooled analysis from 4 prospective clinical trials of gemcitabine-based therapy combined with bevacizumab.

MATERIALS AND METHODS

Data were collected from individual databases from 4 prospective, single-arm phase II trials. Patients were grouped according to B-HTN or no hypertension (HTN), and patients with HTN were further grouped according to highest Common Terminology Criteria for Adverse Events grade of HTN: grade 1-2 or grade 3-4. Clinical outcomes of overall survival, time to progression, overall response rate (ORR), and disease control rate (ORR+SD>16 wk) were compared.

RESULTS

A total of 163 patients with stage IV APCA and Eastern Cooperative Oncology Group 0-1 were included. Median age was 59 years (range, 33 to 85 y). Thirty-four patients had B-HTN, and 129 patients had no HTN. Prognostic factors were balanced between groups. Patients with any grade B-HTN had a significantly improved median overall survival (13.1 vs. 8.1 mo, P=0.0006), median time to tumor progression (7.6 vs. 5.5 mo, P=0.0074), ORR (47% vs. 16%, P=0.0001), and disease control rate (85% vs. 59%, P=0.004). There were no differences in outcomes according to HTN grade (1-2 [N=16] vs. 3-4 [N=18]).

CONCLUSIONS

APCA patients who develop any grade of B-HTN appear to derive benefit from bevacizumab. Additional investigation is needed to identify subgroups of patients who develop B-HTN and are more likely to benefit from bevacizumab.

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.

Phase II clinical trials on investigational drugs for the treatment of pancreatic cancers

INTRODUCTION

Despite some recent advances in treatment options, pancreatic cancer remains a devastating disease with poor outcomes. In a trend contrary to most malignancies, both incidence and mortality continue to rise due to pancreatic cancer. The majority of patients present with advanced disease and there are no treatment options for this stage that have demonstrated a median survival > 1 year. As the penultimate step prior to Phase III studies involving hundreds of patients, Phase II clinical trials provide an early opportunity to evaluate the efficacy of new treatments that are desperately needed for this disease.

AREAS COVERED

This review covers the results of published Phase II clinical trials in advanced pancreatic adenocarcinoma published within the past 5 years. The treatment results are framed in the context of the current standards of care and the historic challenge of predicting Phase III success from Phase II trial results.

EXPERT OPINION

Promising therapies remain elusive in pancreatic cancer based on recent Phase II clinical trial results. Optimization and standardization of clinical trial design in the Phase II setting, with consistent incorporation of biomarkers, is needed to more accurately identify promising therapies that warrant Phase III evaluation.

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.

Should combination chemotherapy serve as the backbone in clinical trials of advanced pancreatic cancer? A pooled analysis of phase II trials of gemcitabine-containing doublets plus bevacizumab

OBJECTIVE

The objective of this study was to evaluate whether building upon multidrug chemotherapy regimens represents a viable strategy in pancreatic cancer clinical trial design.

METHODS

We performed a pooled analysis of all single-arm phase II studies in which a specific targeted agent (the anti-vascular endothelial growth factor monoclonal antibody bevacizumab) was added to gemcitabine-based cytotoxic doublets. The primary end point was overall survival (OS). Secondary end points included objective response rate, CA-19-9 biomarker response rate, and adverse event frequencies. Kaplan-Meier methods estimated time-to-event end points, whereas the Cox proportional hazard model estimated univariate hazard ratios of death.

RESULTS

For the 300 patients included in the pooled analysis, median OS was 9.1 months (95% confidence interval, 8.3-10.2). Differences in OS were observed according to patients' baseline performance status (median OS, 10.4 vs 8.6 months for Eastern Cooperative Oncology Group 0 vs 1, respectively). Moreover, bevacizumab-related adverse events were not observed at increased frequency with gemcitabine-based doublets compared with historic data.

CONCLUSIONS

Recognizing the limitations of cross-study comparisons, these results compare favorably to those from Cancer and Leukemia Group B 80303, a phase III trial testing bevacizumab in combination with gemcitabine alone. This is the largest data set available to demonstrate the feasibility of building upon more intensive chemotherapy backbones in clinical trials of novel targeted agents in pancreatic cancer.

Baseline serum albumin is a predictive biomarker for patients with advanced pancreatic cancer treated with bevacizumab: a pooled analysis of 7 prospective trials of gemcitabine-based therapy with or without bevacizumab

BACKGROUND

Phase 3 studies of bevacizumab in patients with advanced pancreatic cancer (APCA) demonstrated no improvement in outcome. To the authors' knowledge, no validated predictive biomarkers for bevacizumab exist, although emerging data suggest that subsets of patients with APCA may benefit from treatment with bevacizumab. The authors evaluated baseline serum albumin (b-alb) as a predictive biomarker in a pooled analysis from 7 prospective clinical trials of gemcitabine-based therapy with or without bevacizumab.

METHODS

Data were collected from individual databases from 7 prospective clinical trials. Patients were grouped by exposure to bevacizumab and by b-alb level (≥ 3.4 g/L or < 3.4 g/dL). Overall survival (OS), time to disease progression (TTP), overall response rate, and disease control rate (overall response rate plus stable disease lasting ≥ 16 weeks) were compared between groups. Univariate and multivariable analyses of prognostic factors were performed.

RESULTS

A total of 264 patients were included. The median age was 59 years (range, 31 years-85 years) and all patients had stage IV disease per TNM staging. Normal b-alb was associated with significantly improved median OS (10.2 months vs 4.1 months; P = .0001), median TTP (6.2 months vs 3.7 months; P = 0.0488), and disease control rate (71% vs 46%; P = .007) for patients receiving bevacizumab, but not for those treated without bevacizumab. Multivariable analysis revealed a significant influence of normal b-alb on OS (P = .0008) and TTP (P = .033).

CONCLUSIONS

Patients with APCA with normal b-alb derive benefit from treatment with bevacizumab. Future prospective investigations of bevacizumab in patients with APCA should consider selecting patients with normal b-alb to maximize potential benefit.

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.

Toward the goal of personalized therapy in pancreatic cancer by targeting the molecular phenotype

The purpose of this article is to provide a critical review of the molecular alterations in pancreatic cancer that are clinically investigated as therapeutic targets and their potential impact on clinical outcomes. Adenocarcinoma of exocrine pancreas is generally associated with poor prognosis and the conventional therapies are marginally effective. Advances in understanding the genetic regulation of normal and neoplastic development of pancreas have led to development and clinical evaluation of new therapeutic strategies that target the signaling pathways and molecular alterations in pancreatic cancer. Applications have begun to utilize the genetic targets as biomarkers for prediction of therapeutic responses and selection of treatment options. The goal of accomplishing personalized tumor-specific therapy with tolerable side effects for patients with pancreatic cancer is hopefully within reach in the foreseeable future.

Impact of targeted neoadjuvant therapies in the treatment of solid organ tumours

BACKGROUND

The advent of affordable technologies to perform detailed molecular profiling of tumours has transformed understanding of the specific genetic events that promote carcinogenesis and which may be exploited therapeutically. The application of targeted therapeutics has led to improved outcomes in advanced disease and this approach is beginning to become established in the management of potentially curable disease for surgical patients.

METHODS

This review article focuses on recent developments in the management of operable cancers of the gastrointestinal (GI) tract, specifically discussing the currently available data that evaluate the incorporation of targeted therapies in this setting.

RESULTS

A variety of targeted molecules are now available as treatment options in the management of GI cancers. Most are aimed at growth inhibition by acting on cell surface targets or intracellular pathways. Treatment paradigms are gradually shifting towards more prevalent use of systemic treatment prior to surgical intervention for operable disease with the aim of tumour downsizing and improved rates of long-term cure.

CONCLUSION

A large number of ongoing clinical trials are evaluating novel targeted agents as neoadjuvant therapy in operable GI tumours. Therefore, further progress in the management of early-stage disease will undoubtedly be made over the next few years as these trials continue to report potentially practice-changing results.

VEGF remains an interesting target in advanced pancreas cancer (APCA): results of a multi-institutional phase II study of bevacizumab, gemcitabine, and infusional 5-fluorouracil in patients with APCA

BACKGROUND

We investigated the safety and efficacy of bevacizumab combined with gemcitabine followed by infusional 5-fluorouracil (5-FU) in patients with advanced pancreas cancer (APCA).

DESIGN

Patients with untreated APCA received bevacizumab 10 mg/kg, gemcitabine 1000 mg/m(2) over 100 min, and 5-FU 2400 mg/m(2) over 48 h on days 1 and 15 of each 28-day cycle. The primary end point was the proportion of patients with progression-free survival (PFS) at 6 months from initiation of therapy. If PFS at 6 months was ≥41%, the regimen would be considered promising.

RESULTS

Forty-two patients were enrolled in the study; of which, 39 were evaluable for primary end point. PFS at 6 months was 49% (95% CI 34% to 64%). Median PFS was 5.9 months (95% CI 3.5 to 8.1) and median overall survival (OS) was 7.4 months (95% CI 4.7 to 11.2). Partial response and stable disease occurred in 30% and 45% of patients, respectively. Treatment-related hypertension and normal baseline albumin correlated with an improved response rate, PFS and OS. Grade 3 to 4 toxicities included fatigue (14%), hypertension (5%), and venous thrombosis (5%).

CONCLUSIONS

The study met its primary end point. Further investigation of anti-VEGF therapy in combination with fluoropyrimidine-based therapy is warranted in APCA. Treatment-related hypertension and normal baseline albumin may predict for the efficacy of bevacizumab and should be investigated in prospective studies.

Systemic therapies for pancreatic cancer--the role of pharmacogenetics

Effective systemic treatment of pancreatic cancer remains a major challenge, with progress hampered by drug resistance and treatment related toxicities. Currently available cytotoxic agents as monotherapy or in combination have provided only a modest survival benefit for patients with advanced disease. Disappointing phase III results with gemcitabine-based combinations in patients with advanced pancreatic cancer might be related to poor efficacy of systemic therapies in unselected patients. Future research strategies should prioritize identification of predictive markers through pharmacogenetic investigations. The individualization of patient treatment through pharmacogenetics may help to improve outcome by maximizing efficacy whilst lowering toxicity. This review provides an update on the pharmacogenetics of pancreatic cancer treatment and its influence on treatment benefits and toxicity.

Systemic therapies for pancreatic cancer--the role of pharmacogenetics

Effective systemic treatment of pancreatic cancer remains a major challenge, with progress hampered by drug resistance and treatment related toxicities. Currently available cytotoxic agents as monotherapy or in combination have provided only a modest survival benefit for patients with advanced disease. Disappointing phase III results with gemcitabine-based combinations in patients with advanced pancreatic cancer might be related to poor efficacy of systemic therapies in unselected patients. Future research strategies should prioritize identification of predictive markers through pharmacogenetic investigations. The individualization of patient treatment through pharmacogenetics may help to improve outcome by maximizing efficacy whilst lowering toxicity. This review provides an update on the pharmacogenetics of pancreatic cancer treatment and its influence on treatment benefits and toxicity.

Systemic treatment of advanced pancreatic cancer

Pancreatic cancer belongs to the most malignant gastrointestinal cancers and, in its advanced stage, remains a deadly disease for nearly all affected patients. Treatment of metastatic adenocarcinoma of the pancreas not only involves chemotherapy and targeted therapy, but also requires attention to accompanying comorbidities as well as frequently intensive supportive treatment and psychosocial support. Gemcitabine-based combinations with fluoropyrimidines and platin analogs have essentially failed to provide a substantial prolongation of survival and may constitute a treatment option only in patients with a good performance status. Among targeted therapies, only the EGFR tyrosine kinase inhibitor erlotinib has shown activity which is marginal in the overall population, but clinically relevant in patients developing skin rash. New avenues of polychemotherapy are presently explored since the gemcitabine-free FOLFIRINOX-regimen (infusional 5-fluorouracil/folinic acid plus irinotecan and oxaliplatin) was shown to be markedly superior to gemcitabine in selected good-performance patients. Pancreatic cancer is notably characterized as a hypovascular tumor rich in desmoplastic stromal tissue. An innovative approach to treatment therefore focuses on peritumoral fibroblasts and aims to induce a depletion of the stroma either by inhibition of the hedgehog pathway or by targeting SPARC (secreted protein acidic and rich in cysteine) via application of albumin-bound paclitaxel.

Emerging therapies in pancreas cancer

Pancreas cancer has a grave prognosis and treatment options remain limited despite advancement in anti-cancer chemotherapeutics. This review provides an overview of the emerging therapies for pancreas cancer, focusing on novel signal transduction inhibitors (insulin-like growth factor receptor, hedgehog/Smo, PI3k/Akt/mTOR) and cytotoxics (nab-paclitaxel) that are currently in clinical development. Despite the impact molecularly targeted agents have on other tumor types, their application without cytotoxics in pancreas cancer remains limited. In addition, recent report of the superiority of an intensive cytotoxic regimen using fluorouracil, irinotecan and oxaliplatin (FOLFIRINOX) over gemcitabine reminded us of the importance of cytotoxics in this disease. As such, the future of pancreas cancer therapy may be combination regimens consisting of cytotoxics and molecularly targeted agents.