Triplet combination of durvalumab, tremelimumab, and paclitaxel in biliary tract carcinomas: Safety run-in results of the randomized IMMUNOBIL PRODIGE 57 phase II trial

Immunobiology of biliary tract cancer and recent clinical findings in approved and upcoming immune checkpoint inhibitors

INTRODUCTION

Recently, immunotherapy has offered new hope for treating biliary tract cancer (BTC). However, several issues are to be considered, including the lack of validated predictive biomarkers that could help to identify patient groups which are most likely to benefit from such therapeutic approaches.

AREAS COVERED

In the current article, we will provide an overview of recent results and ongoing and future research directions of immunotherapy in BTC, with a special focus on recently published, practice-changing data, and ongoing active and recruiting clinical trials.

EXPERT OPINION

At this moment, dozens of clinical trials in phases I to III are evaluating the role of cancer immunotherapy in this setting, with the hope of adding more therapeutic options for BTC patients. Future research must focus on the development of novel agents and combinations, but the validation of biomarkers remains an urgent need. As more research results emerge, novel combinatorial strategies are destined to further transform the treatment paradigm for this heterogeneous and aggressive tumor type.

Recent Advances in Immunotherapy for Advanced Biliary Tract Cancer

OPINION STATEMENT

Biliary tract cancer (BTC) is a heterogeneous group of aggressive malignancies that arise from the epithelium of the biliary tract. Most patients present with locally advanced or metastatic disease at the time of diagnosis. For patients with unresectable BTC, the survival advantage provided by systemic chemotherapy was limited. Over the last decade, immunotherapy has significantly improved the therapeutic landscape of solid tumors. There is an increasing number of studies evaluating the application of immunotherapy in BTC, including immune checkpoint inhibitors (ICIs), cancer vaccines and adoptive cell therapy. The limited response to ICIs monotherapy in unselected patients prompted investigators to explore different combination therapy strategies. Early clinical trials of therapeutic cancer vaccination and adoptive cell therapy have shown encouraging clinical results. However, there still has been a long way to go via validation of therapeutic efficacy and exploration of strategies to increase the efficacy. Identifying biomarkers that predict the response to immunotherapy will allow a more accurate selection of candidates. This review will provide an up-to-date overview of the current clinical data on the role of immunotherapy, summarize the promising biomarkers predictive of the response to ICIs and discuss the perspective for future research direction of immunotherapy in advanced BTC.

"On/off"-switchable crosslinked PTX-nanoformulation with improved precise delivery for NSCLC brain metastases and restrained adverse reaction over nab-PTX

Non-small cell lung cancer (NSCLC) brain metastases present a significant treatment challenge due to limited drug delivery efficiency and severe adverse reactions. In this study, we address these challenges by designing a "on/off" switchable crosslinked paclitaxel (PTX) nanocarrier, BPM-PD, with novel ultra-pH-sensitive linkages (pH 6.8 to 6.5). BPM-PD demonstrates a distinct "on/off" switchable release of the anti-cancer drug paclitaxel (PTX) in response to the acidic extratumoral microenvironment. The "off" state of BPM-PD@PTX effectively prevents premature drug release in the blood circulation, blood-brain barrier (BBB)/blood-tumor barrier (BTB), and normal brain tissue, surpassing the clinical PTX-nanoformulation (nab-PTX). Meanwhile, the "on" state facilitates precise delivery to NSCLC brain metastases cells. Compared to nab-PTX, BPM-PD@PTX demonstrates improved therapeutic efficacy with a reduced tumor area (only 14.6%) and extended survival duration, while mitigating adverse reactions (over 83.7%) in aspartate aminotransferase (AST) and alanine aminotransferase (ALT), offering a promising approach for the treatment of NSCLC brain metastases. The precise molecular switch also helped to increase the PTX maximum tolerated dose from 25 mg/kg to 45 mg/kg This research contributes to the field of cancer therapeutics and has significant implications for improving the clinical outcomes of NSCLC patients.

Evaluating the Therapeutic Potential of Durvalumab in Adults with Locally Advanced or Metastatic Biliary Tract Cancer: Evidence to Date

Advanced biliary tract cancers (BTCs) have historically been managed with chemotherapy but, in recent years, this treatment paradigm has begun to shift with the introduction of immune checkpoint inhibitors in addition to standard of care chemotherapy. The tumor microenvironment of BTC may be enriched with regulatory T lymphocytes and immune checkpoint expression in some patients. Durvalumab, an anti-programmed death ligand-1 (PD-L1) antibody, in combination with gemcitabine and cisplatin, has now received United States Food and Drug Administration approval for treatment of advanced BTC. Regulatory approval was based on the Phase III, randomized TOPAZ-1 trial that demonstrated survival benefit with addition of durvalumab to gemcitabine plus cisplatin compared to chemotherapy alone. The combination of chemotherapy and immunotherapy was well tolerated, and a subset of patients were able to achieve a durable response, with a 2-year overall survival rate of 23.6%. However, limitations remain in identifying which patients are most likely to benefit from immune checkpoint inhibition. Future study should aim to identify biomarkers predictive of substantial benefit, as well as the role of immune checkpoint inhibition in combination with targeted therapies and radiotherapy in the management of advanced BTC.

Unresectable biliary tract cancer: Current and future systemic therapy

For decades, treatment of advanced biliary tract cancer (BTC) was confined to the use of chemotherapy. In recent years however, the number of therapeutic options available for patients with unresectable BTC have drastically increased, with immunotherapy and targeted treatment gradually joining the ranks of guideline-recommended treatment regimens. The aim of the present review is to summarise the current knowledge on unresectable BTC focusing on epidemiology, anatomical distribution and current strategies for systemic treatment. We further outline ongoing clinical trials and provide an outlook on future therapeutic interventions. In the realm of gastrointestinal malignancies, the increasing number of systemic treatment options for BTC is finally delivering on the longstanding commitment to personalised oncology. This emphasises the need for considering a comprehensive genomic-based pathology assessment right from the initial diagnosis to fully leverage the expanding array of therapeutic options that have recently become accessible.

Preclinical and clinical studies of immunotherapy for the treatment of cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare primary liver cancer associated with high mortality and few systemic treatment options. The behaviour of the immune system has come into focus as a potential treatment modality for many cancer types, but immunotherapy has yet to dramatically alter the treatment paradigm for CCA as it has for other diseases. Herein, we review recent studies describing the relevance of the tumour immune microenvironment (TIME) in CCA. Various non-parenchymal cell types are critically important in controlling CCA progression, prognosis, and response to systemic therapy. Knowledge of the behaviour of these leukocytes could help generate hypotheses to guide the development of potential immune-directed therapies. Recently, an immunotherapy-containing combination was approved for the treatment of advanced-stage CCA. However, despite level 1 evidence demonstrating the improved efficacy of this therapy, survival remained suboptimal. In the current manuscript, we provide a comprehensive review of the TIME in CCA, preclinical studies of immunotherapies against CCA, as well as ongoing clinical trials applying immunotherapies for the treatment of CCA. Particular emphasis is placed on microsatellite unstable tumours, a rare CCA subtype that demonstrates heightened sensitivity to approved immune checkpoint inhibitors. We also discuss the challenges involved in applying immunotherapies to the treatment of CCA and the importance of understanding the TIME.

Combination Therapies for Advanced Biliary Tract Cancer

Biliary tract cancers (BTCs) are a group of malignant neoplasms that have recently increased in incidence and have a poor prognosis. Surgery is the only curative therapy. However, most patients are only indicated for palliative therapy because of advanced-stage disease at diagnosis and rapid progression. The current first-line treatment for advanced BTC is gemcitabine and cisplatin chemotherapy. Nonetheless, many patients develop resistance to this regimen. Over the years, few chemotherapy regimens have managed to improve the overall survival of patients. Accordingly, novel therapies such as targeted therapy have been introduced to treat this patient population. Extensive research on tumorigenesis and the genetic profiling of BTC have revealed the heterogenicity and potential target pathways, such as EGFR, VEGF, MEK/ERK, PI3K and mTOR. Moreover, mutational analysis has documented the presence of IDH1, FGFR2, HER2, PRKACA, PRKACB, BRAF, and KRAS gene aberrations. The emergence of immunotherapy in recent years has expanded the treatment landscape for this group of malignancies. Cancer vaccines, adoptive cell transfer, and immune checkpoint inhibitors have been extensively investigated in trials of BTC. Therefore, patient stratification and a combination of various therapies have become a reasonable and important clinical strategy to improve patient outcomes. This review elaborates the literature on combined treatment strategies for advanced BTC from the past few years and ongoing clinical trials to provide new inspiration for the treatment of advanced BTC.

Immune checkpoint inhibitors and combinations with other agents in cholangiocarcinoma

Cholangiocarcinoma consists of a heterogeneous group of malignancies with generally poor prognoses. Immunotherapy has emerged in the treatment landscape of many tumors, offering survival benefits, but data regarding the use of immunotherapy for cholangiocarcinoma remain vague. In this review, the authors analyze differences in the tumor microenvironment and various immune escape mechanisms and discuss available immunotherapy combinations with other agents among completed and ongoing clinical trials, such as chemotherapy, targeted agents, antiangiogenic drugs, local ablative therapies, cancer vaccines, adoptive cell therapy and PARP and TGF-β inhibitors. Ongoing research to identify appropriate biomarkers is warranted.

Immunotherapies in rare cancers

Cancer remains a leading cause of death worldwide, placing a significant burden on healthcare systems as well as the global economy. Rare cancers comprise a group of about 200 cancers that individually occur at extremely low frequencies. In the United States (US), their frequency is approximately 15 cases per 100,000 people, and it is even lower in Europe with approximately 6 cases per 100,000 people. However, combined their frequency of occurrence is much higher than any singular cancer. Cancer treatment and management has tremendously improved in the last decade, particularly with the administration of immune-based therapies. The four most prevalent immune-based therapies are (1) the use of immune-checkpoint inhibitors, (2) macrophage therapy, (3) Chimeric Antigen Receptor (CAR) T cell therapy, and (4) neoantigen-based therapies. In our review, we discuss these various aproaches and their implementation in the treatment of a variety of rare cancers. Furthermore, we discuss their limitations and potential strategies to overcome them to enhance the therapeutic efficacy of these approaches. Finally, our article presents the future directions and other additional immune therapies that may be incorporated into the treatment of rare cancers.

The clinical value of identifying genetic abnormalities that can be targeted in cholangiocarcinomas

INTRODUCTION

Cholangiocarcinomas (CCAs) are a heterogenous group of epithelial malignancies originating at any level of the biliary tree and are subdivided according to their location into intrahepatic (iCCA) and extrahepatic (eCCA).

AREAS COVERED

This review provides an updated analysis of studies of genetic characterization of CCA at the level of gene mutation profiling, copy number alterations and gene expression, with definition of molecular subgroups and identification of some molecular biomarkers and therapeutic targets.

EXPERT OPINION

With the development of genetic sequencing, several driver mutations have been identified and targeted as novel therapeutic approaches, including FGFR2, IDH1, BRAF, NTRK, HER2, ROS, and RET. Furthermore, identification of the cellular and molecular structure of the tumor microenvironment has contributed to the development of novel therapies, such as tumor immunotherapy. Combination therapies of chemotherapy plus targeted molecules or immunotherapy are under evaluation and offer the unique opportunity to improve the outcomes of CCA patients with advanced disease.

Immune checkpoints and their promising prospect in cholangiocarcinoma treatment in combination with other therapeutic approaches

Cholangiocarcinoma (CCA) is one of the malignant tumors that has shown rapid development in incidence and mortality in recent years. Like other types of cancer, patients with CCA experience alterations in the expression of immune checkpoints, indicating the importance of immune checkpoint inhibitors in treating CCA. The results of TCGA analysis in this study revealed a marginal difference in the expression of important immune checkpoints, Programmed cell death 1 (PD-1) and Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and their ligands in CCA samples compared to normal ones. This issue showed the importance of combination therapy in this cancer. This review considers CCA treatment and covers several therapeutic modalities or combined treatment strategies. We also cover the most recent developments in the field and outline the important areas of immune checkpoint molecules as prognostic variables and therapeutic targets in CCA.

Optimizing Patient Pathways in Advanced Biliary Tract Cancers: Recent Advances and a French Perspective

Biliary tract cancers (BTCs) are a heterogeneous group of tumors that are rare in Western countries and have a poor prognosis. Three subgroups are defined by their anatomical location (intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma and gallbladder carcinoma) and exhibit distinct clinical, molecular, and epidemiologic characteristics. Most patients are diagnosed at an advanced disease stage and are not eligible for curative-intent resection. In addition to first- and second-line chemotherapies (CisGem and FOLFOX, respectively), biologic therapies are now available that target specific genomic alterations identified in BTC. To date, targets include alterations in the genes for isocitrate dehydrogenase (IDH) 1, fibroblast growth factor receptor (FGFR) 2, v-raf murine sarcoma viral oncogene homolog B1 (BRAF), human epidermal growth factor receptor 2 (HER2 or ERRB2), and neurotrophic tyrosine receptor kinase (NTRK), and for those leading to DNA mismatch repair deficiency. Therapies targeting these genomic alterations have demonstrated clinical benefit for patients with BTC. Despite these therapeutic advancements, genomic diagnostic modalities are not widely used in France, owing to a lack of clinician awareness, local availability of routine genomic testing, and difficulties in obtaining health insurance reimbursement. The addition of durvalumab, a monoclonal antibody targeting the immune checkpoint programmed cell death ligand-1, to CisGem in the first-line treatment of advanced BTC has shown an overall survival benefit in the TOPAZ-1 trial. Given the high mortality rates associated with BTC and the life-prolonging therapeutic options now available, it is hoped that the data presented here will support updates to the clinical management of BTC in France.

Treatment-related adverse events of PD-1/PD-L1 inhibitors combined with CTLA-4 inhibitors in clinical trials: a meta-analysis

AIM

PD-1/PD-L1 inhibitors in combination with CTLA-4 inhibitors are being tested in a number of ongoing clinical trials. As a result, it is critical to fully comprehend the toxicity characteristics of adverse events in combination therapy. This study aims to extensively compare the incidences and ORs of treatment-related adverse events between two combination strategies.

METHODS

The eligible articles were searched from PubMed, EMBASE and Cochrane databases for studies published between 1 January 2010 and 1 May 2021, investigating PD-1/PD-L1 inhibitors plus CTLA-4 inhibitor-based combined clinical therapies. The mean incidences and pooled ORs of all-grade and grade 3 or higher adverse events were calculated by random-effects model using Stata 12.1. Heterogeneity between studies was assessed with I² statistics and Chi square-based Q statistic. The overall risk of bias was assessed by Review Manager 5.3.

RESULTS

A total of 26 eligible studies of 3607 patients were selected; 2852 patients developed at least one all-grade adverse event. PD-L1 inhibitors plus CTLA-4 inhibitors regimen (incidence 0.67, 95% CI: 0.57-0.77) had marked advantage over PD-1 inhibitors plus CTLA-4 inhibitors regimen (incidence 0.89, 95% CI: 0.86-0.93).

CONCLUSION

PD-L1 inhibitors plus CTLA-4 inhibitors shows better safety in treatment-related adverse events than PD-1 inhibitors plus CTLA-4 inhibitors.

Therapeutic Antibodies in Cancer Treatment in the UK

The growing understanding of the molecular mechanisms of carcinogenesis accelerated the development of monoclonal therapeutic antibodies to specifically target multiple cancer pathways. Recombinant protein therapeutics now constitute a large proportion of yearly approved medicines. Oncology, autoimmune diseases and to a smaller degree the prophylaxis of organ transplant rejection are their main application areas. As of the date of this review, 37 monoclonal antibody products are approved for use in cancer treatments in the United Kingdom. Currently, the antibody therapeutics market is dominated by monoclonal immunoglobulins (IgGs). New types of recombinant antibody therapeutics developed more recently include bispecific recombinant antibodies and other recombinantly produced functional proteins. This review focuses on the approved therapeutic antibodies used in cancer treatment in the UK today and describes their antigen targets and molecular mechanisms involved. We provide convenient links to the relevant databases and other relevant resources for all antigens and antibodies mentioned. This review provides a comprehensive summary of the different monoclonal antibodies that are currently in clinical use primarily in malignancy, including their function, which is of importance to those in the medical field and allied specialties.

Molecular therapeutic targets for cholangiocarcinoma: Present challenges and future possibilities

A diagnosis of cholangiocarcinoma (CCA) is implicit with poor prognosis and limited treatment options, underscoring the near equivalence of incidence and mortality rates in this disease. In less than 9years from genomic identification to FDA-approval of the corresponding inhibitors, fibroblast growth factor receptor 2 (FGFR2) rearrangements and isocitrate dehydrogenase 1 (IDH1) mutations became exemplary successes of precision oncology in subsets of patients with CCA. However, clinical trial results from multikinase inhibitors in unselected populations have been less successful, while the impact of immunotherapies are only beginning to impact this setting. Development of future therapeutics is incumbent with new challenges. Many driver alterations occur in tumor suppressor-like genes which are not directly druggable. Therapeutically, this will require identification of ensuant "non-oncogene addiction" involving genes which are not themselves oncogenes but become tumor survival dependencies when a specific driver alteration occurs. The low recurrence frequency of genomic alterations between CCA patients will require careful evaluation of targeted agents in biomarker-enrolled trials, including basket trial settings. Systematic expansion of candidate drug targets must integrate genes affected by non-genetic alterations which incorporates the fundamental contribution of the microenvironment and immune system to treatment response, disease facets which have been traditionally overlooked by DNA-centric analyses. As treatment resistance is an inevitability in advanced disease, resistance mechanisms require characterization to guide the development of combination therapies to increase the duration of clinical benefit. Patient-focused clinical, technological and analytical synergy is needed to deliver future solutions to these present therapeutic challenges.

The state of therapy modalities in clinic for biliary tract cancer

Biliary tract cancers (BTCs) include intrahepatic cholangiocarcinoma (iCCA), perihilar and distal cholangiocarcinoma (pCCA and dCCA), and gallbladder carcinoma based on the epithelial site of origin. BTCs are highly aggressive tumors associated with poor prognosis due to widespread metastasis and high recurrence. Surgery is the typical curative-intent treatment, yet the cornerstone of cure depends on the anatomical site of the primary tumor, and only a minority of patients (approximately 30%) has an indication necessitating surgery. Similarly, only a small subset of carefully selected patients with early iCCA who are not candidates for liver resection can opt for liver transplantation. Chemotherapy, target therapy, and immunotherapy are the main treatment options for patients who have advanced stage or unresectable disease. The genetic background of each cholangiocarcinoma subtype has been accurately described based on whole gene exome and transcriptome sequencing. Accordingly, precision medicine in targeted therapies has been identified to be aimed at distinct patient subgroups harboring unique molecular alterations. Immunotherapy such as immune checkpoint inhibitors (ICIs) was identified as antitumor responses in a minority of select patients. Current studies indicate that immunotherapy of adoptive cell therapy represents a promising approach in hematological and solid tumor malignancies, yet clinical trials are needed to validate its effectiveness in BTC. Herein, we review the progress of BTC treatment, stratified patients according to the anatomic subtypes of cholangiocarcinoma and the gene drivers of cholangiocarcinoma progression, and compare the efficacy and safety of chemotherapy, targeted therapy, and immunotherapy, which will be conducive to the design of individualized therapies.

Efficacy and Safety of Anti-PD1/PDL1 in Advanced Biliary Tract Cancer: A Systematic Review and Meta-Analysis

Background

Anti-programmed cell death protein 1 and its ligand (anti-PD1/PDL1) have been proposed as a promising therapeutic option for advanced biliary tract cancer (aBTC). Given the scarce quantitative analyses of anti-PD1/PDL1 in aBTC, we thus did a meta-analysis to assess the benefits and risks of this emerging treatment strategy in patients with aBTC.

Methods

PubMed, Embase, the Cochrane Library, Web of Science, and meeting resources were searched for relevant studies. The main endpoints were median progression-free survival (mPFS), median overall survival (mOS), objective response rate (ORR), disease control rate (DCR), any-grade adverse events (AEs), and grade 3-4 AEs.

Results

Twenty-eight studies with 1,338 participants were included. The best curative effect was found in the anti-PD1/PDL1 combined with anti-CTLA4 and chemotherapy group (mPFS: 12.4 months; mOS: 16.0 months; ORR: 45.1%; DCR: 95.0%), followed by the anti-PD1/PDL1 plus chemotherapy group (mPFS: 8.2 months; mOS: 14.8 months; ORR: 36.3%; DCR: 84.6%), the anti-PD1/PDL1 plus antiangiogenesis group (mPFS: 4.9 months; mOS: 10.2 months; ORR: 17.5%; DCR: 68.7%), the anti-PD1/PDL1 plus anti-cytotoxic T lymphocyte antigen 4 (anti-CTLA4) group (mPFS: 2.9 months; mOS: 8.3 months; ORR: 9.9%; DCR: 36.8%), and the anti-PD1/PDL1 monotherapy group (mPFS: 2.5 months; mOS: 7.6 months; ORR: 6.8%; DCR: 34.7%). Compared with anti-PD1-containing regimens, anti-PDL1-containing regimens achieved preferable mPFS (11.1 vs. 3.8 months), mOS (12.2 vs. 9.8 months), and ORR (23.7% vs. 17.4%), despite a similar DCR (61.1% vs. 61.3%). The mPFS, mOS, ORR, and DCR were 10.6 months, 15.8 months, 42.3%, and 88.6% of first-line anti-PD1/PDL1 and 3.0 months, 9.1 months, 11.6%, and 51.1% of second-line therapy or beyond, respectively. There were 80.6% and 34.0% of the patients suffering any-grade AEs and grade 3-4 AEs. Anti-PD1/PDL1 monotherapy might be considered as a safer alternative than combination regimens. Meanwhile, obvious toxicities in the first-line setting could not be neglected.

Conclusions

Anti-PD1/PDL1 showed encouraging efficacy and acceptable safety profile in aBTC and, thus, could be an alternative treatment.

An Insight into the Novel Immunotherapy and Targeted Therapeutic Strategies for Hepatocellular Carcinoma and Cholangiocarcinoma

Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) constitute highly malignant forms of primary liver cancers. Hepatocellular and bile duct carcinogenesis is a multiplex process, caused by various genetic and epigenetic alterations, the influence of environmental factors, as well as the implication of the gut microbiome, which was undervalued in the previous years. The molecular and immunological analysis of the above malignancies, as well as the identification of the crucial role of intestinal microbiota for hepatic and biliary pathogenesis, opened the horizon for novel therapeutic strategies, such as immunotherapy, and enhanced the overall survival of cancer patients. Some of the immunotherapy strategies that are either clinically applied or under pre-clinical studies include monoclonal antibodies, immune checkpoint blockade, cancer vaccines, as well as the utilization of oncolytic viral vectors and Chimeric antigen, receptor-engineered T (CAR-T) cell therapy. In this current review, we will shed light on the recent therapeutic modalities for the above primary liver cancers, as well as on the methods for the enhancement and optimization of anti-tumor immunity.

Evolving Role of Immunotherapy in Advanced Biliary Tract Cancers

Biliary tract cancers (BTC) comprise a rare and diverse group of malignancies that involve the gallbladder and biliary tree. These cancers typically present in later stages because they are aggressive in nature and affected patients are often asymptomatic in earlier stages of disease. Moreover, BTCs are generally refractory to cytotoxic chemotherapy, which further contributes to their associated poor survival outcomes. Novel therapy approaches are clearly needed. Molecular targeted agents have been developed based on our expanding knowledge of the genetic mutations underlying BTCs and represent a promising treatment strategy in molecularly selected subgroups of patients. In addition, the advent of immunotherapy over recent years has dramatically changed the bleak outcomes observed in malignancies such as melanoma. Our growing understanding of the complex tumor microenvironment in BTC has identified mechanisms of tumor immune evasion that could potentially be targeted with immunotherapy. As a result, different immunotherapeutic approaches including immune checkpoint inhibitors, cancer vaccines, and adoptive cell therapy, have been investigated. The use of immunotherapeutic agents is currently only approved for a small subset of treatment-refractory BTCs based on microsatellite instability (MSI) status and tumor mutational burden (TMB), but this will likely change with the potential approval of immunotherapy plus chemotherapy as a result of the TOPAZ-1 trial.

Immune Checkpoint Inhibitors for Advanced Biliary Tract Cancer

BTC is a rare and aggressive cancer disease bearing an overall dismal prognosis with only finite therapy options. Only combination chemotherapy regimens achieve disease control which is often only short-lived since the tumor tissue exhibits a high resistance to chemotherapy. The emergence of immune checkpoint inhibitors in recent years has significantly improved the survival of cancer patients and thus, has been integrated in the therapeutic management of several solid tumors, including melanoma, colorectal carcinoma (CRC), hepatocellular carcinoma (HCC), triple-negative breast cancer (TNBC), non-small-cell lung cancer (NSCLC). Investigation of the tumor biology of BTC and results of preliminary studies have shown that BTC may also be amenable to immunomodulation. In this review, we seek to give a comprehensive overview about the role, potential and clinical significance of ICPI in the management of BTC.

Immunotherapy for Biliary Tract Cancer in the Era of Precision Medicine: Current Knowledge and Future Perspectives

Biliary tract cancers (BTC) represent a heterogeneous and aggressive group of tumors with dismal prognosis. For a long time, BTC has been considered an orphan disease with very limited therapeutic options. In recent years a better understanding of the complex molecular landscape of biology is rapidly changing the therapeutic armamentarium. However, while 40-50% of patients there are molecular drivers susceptible to target therapy, for the remaining population new therapeutic options represent an unsatisfied clinical need. The role of immunotherapy in the continuum of treatment of patients with BTC is still debated. Despite initial signs of antitumor-activity, single-agent immune checkpoint inhibitors (ICIs) demonstrated limited efficacy in an unselected population. Therefore, identifying the best partner to combine ICIs and predictive biomarkers represents a key challenge to optimize the efficacy of immunotherapy. This review provides a critical analysis of completed trials, with an eye on future perspectives and possible biomarkers of response.

Current State of Multidisciplinary Treatment in Cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is a highly aggressive malignancy, and its incidence seems to be increasing over the last years. Given the high rate of irresectability at the time of initial diagnosis, new treatment approaches are important to achieve better patient outcomes. Our review provides an overview of current multimodal therapy options across different specialties of gastroenterology/oncology, surgery, and interventional radiology.

SUMMARY

CCA is subdivided into clinically and molecularly distinct phenotypes. Surgical treatment currently is the only potentially curative therapy, but unfortunately, the majority of all patients are not eligible for resection at the time of initial diagnosis due to anatomic location, inadequate hepatic reserve, metastatic disease, or limiting comorbidities. However, multimodal treatment options are available to prolong survival, relieve symptoms, and maintain life quality.

KEY MESSAGES

The treatment of CCA is complex and requires close interdisciplinary collaboration and individualized treatment planning to ensure optimal patient care at specialized centers. Molecular profiling of patients and inclusion into clinical trials is highly recommended.

Efficacy of Immune Checkpoint Inhibitors in Rare Tumours: A Systematic Review

Background

Rare cancers, as defined by the European Union, occur in fewer than 15 out of 100,000 people each year. The International Rare Cancer Consortium defines rare cancer incidence as less than six per 100,000 per year. There is a growing number of reports of the efficacy of immune checkpoint inhibitor (ICI) therapy in patients with rare tumours, and hence, we conducted a comprehensive review to summarise and analyse the available literature.

Methods

A literature search of PubMed was performed on January 31, 2021, using the following ICI names as keywords: ipilimumab, tremelimumab, cemiplimab, nivolumab, pembrolizumab, avelumab, atezolizumab, and durvalumab. Studies on patients with rare tumours who were being treated with ICIs were included. We plotted the overall response rate against the corresponding median survival across a variety of cancer types using linear regression.

Results

From 1,255 publications retrieved during the primary search, 62 publications were selected (with a total of 4,620 patients). Only four were randomised trials. A minority were first-line studies, while the remaining were studies in which ICIs were delivered as salvage therapy in pretreated patients. There was a good correlation between response rate and overall survival (Spearman R2 >0.9) in skin cancers, mesothelioma, and sarcomas.

Conclusions

Treatment of advanced-stage rare tumours with ICI therapy was found to be associated with significant activity in some orphan diseases (e.g., Merkel cell carcinoma) and hepatocellular carcinoma. Several ongoing prospective clinical trials will expand the knowledge on the safety and efficacy of ICI therapy in patients with these rare cancers.

Atezolizumab: an investigational agent for the treatment of biliary tract cancer

INTRODUCTION

Biliary tract cancers (BTCs) have a dismal prognosis and limited treatment options. The role of immunotherapy in BTC is unclear. BTCs respond poorly to PD-(L)1 blockade, highlighting the need for combination regimens to augment antitumor immunity. Atezolizumab (anti-PD-L1) combined with other therapies is under investigation in advanced BTC.

AREAS COVERED

This paper provides an overview of the recent progress and future applications of immunotherapy for BTCs and sheds light on the status and therapeutic potential of atezolizumab. We discuss published data for atezolizumab and an examine the rationale and design of ongoing clinical studies. We offer insights and opinions on the future applications and challenges of immunotherapy in BTC.

EXPERT OPINION

Atezolizumab monotherapy has demonstrated limited antitumor activity in BTC, indicating the need for combination regimens to unlock effective anticancer immunity, and the development of predictive biomarkers to enrich the population. Data for atezolizumab combined with chemotherapy, anti-VEGF agents and other targeted drugs in solid tumors justifies their evaluation in BTC. Several novel atezolizumab-based combinations have been or are currently under investigation in Phase II studies. It is hoped that data from these studies, along with other immunotherapy trials, will provide more effective treatments for patients with BTC.

Role of Inflammatory and Immune-Nutritional Prognostic Markers in Patients Undergoing Surgical Resection for Biliary Tract Cancers

Simple Summary

Biliary tract cancers (BTCs) are a heterogeneous group of malignancies, which arise from the epithelial cells of the biliary tree, with a high rate of local invasion and metastatic spreading. Surgical resection remains the treatment which offers the best chance of long-term survival. However, new chemotherapy regimens and multimodal strategies have showed encouraging results, supporting the need for simple and readily available preoperative tools able to predict survival and guide the treatment strategy. Recently, the prognostic role of several nutritional and inflammatory indexes in growth, biological aggressiveness, and spread has been investigated in different types of cancers. Nevertheless, complete and conclusive results on BTCs are lacking. By identifying a preoperative immune and inflammatory prognostic index based on simple routine blood samples, we may have an additional element that is useful in guiding the treatment strategy by assigning selected patients to preoperative or postoperative treatments despite pathological results.

Abstract

The relationship between immune-nutritional status and tumor growth; biological aggressiveness and survival, is still debated. Therefore, this study aimed to evaluate the prognostic performance of different inflammatory and immune-nutritional markers in patients who underwent surgery for biliary tract cancer (BTC). The prognostic role of the following inflammatory and immune-nutritional markers were investigated: Glasgow Prognostic Score (GPS), modified Glasgow Prognostic Score (mGPS), Prognostic Index (PI), Neutrophil to Lymphocyte ratio (NLR), Platelet to Lymphocyte ratio (PLR), Lymphocyte to Monocyte ratio (LMR), Prognostic Nutritional Index (PNI). A total of 282 patients undergoing surgery for BTC were included. According to Cox regression and ROC curves analysis for survival, LMR had the best prognostic performances, with hazard ratio (HR) of 1.656 (p = 0.005) and AUC of 0.652. Multivariable survival analysis identified the following independent prognostic factors: type of BTC (p = 0.002), T stage (p = 0.014), N stage (p < 0.001), histological grading (p = 0.045), and LMR (p = 0.025). Conversely, PNI was related to higher risk of severe morbidity (p < 0.001) and postoperative mortality (p = 0.005). In conclusion, LMR appears an independent prognostic factor of long-term survival, whilst PNI seems associated with worse short-term outcomes.

Chemotherapy for Biliary Tract Cancer in 2021

Biliary tract cancer refers to a group of malignancies including cholangiocarcinoma, gallbladder cancer, and ampullary cancer. While surgical resection is considered the only curative treatment, postoperative recurrence can sometimes occur. Adjuvant chemotherapy is used to prolong prognosis in some cases. Many unresectable cases are also treated with chemotherapy. Therefore, systemic chemotherapy is widely introduced for the treatment of biliary tract cancer. Evidence on chemotherapy for biliary tract cancer is recently on the increase. Combination chemotherapy with gemcitabine and cisplatin is currently the standard of care for first-line chemotherapy in advanced cases. Recently, FOLFOX also demonstrated efficacy as a second-line treatment. In addition, efficacies of isocitrate dehydrogenase inhibitors and fibroblast growth factor receptor inhibitors have been shown. In the adjuvant setting, capecitabine monotherapy has become the standard of care in Western countries. In addition to conventional cytotoxic agents, molecular-targeted agents and immunotherapy have been evaluated in multiple clinical trials. Genetic testing is used to check for genetic alterations and molecular-targeted agents and immunotherapy are introduced based on tumor characteristics. In this article, we review the latest evidence of chemotherapy for biliary tract cancer.

Durvalumab Plus Tremelimumab in Solid Tumors: A Systematic Review

INTRODUCTION

Cancer immunotherapy represents one of the most important innovations in modern medicine. Durvalumab is an anti-programmed cell death ligand 1 (PDL-1) agent which is currently under investigation in several studies in combination with the anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) drug tremelimumab. The aim of this review was to systematically identify and revise the current scientific literature investigating the combination of these two drugs in solid tumors.

METHODS

A digital search on the Medline (PubMed interface) and Scopus databases for articles published from inception to 26 February 2021 was performed. The terms used for the search were durvalumab AND tremelimumab. Trials reported in English involving adult patients with solid cancers treated with the combination durvalumab plus tremelimumab were retrieved; the references of the articles were cross-checked to identify missing papers.

RESULTS

The electronic search produced 267 results; after exclusion of duplicates, irrelevant articles, reviews, and papers not in English or missing data, 19 articles were included for revision. The total number of patients treated with the combination of durvalumab and tremelimumab in the studies retrieved was 2052.

CONCLUSION

The combination of durvalumab plus tremelimumab showed some oncological advantages in comparison with traditional chemotherapies in some subsets of tumors, but generally has not shown consistent advantages in comparison with the employment of durvalumab monotherapy. A number of the studies examined had intrinsic methodological limitations; therefore, future well-designed studies involving larger cohorts are warranted.

Immunotherapy for cholangiocarcinoma: a 2021 update

Cholangiocarcinoma (CCA) is a rare malignancy with generally dismal prognosis. Immunotherapy has revolutionized the management of cancer patients during the last decade, offering durable responses with an acceptable safety profile, but there are still no significant advances regarding CCA. Novel immunotherapeutic methods, such as cancer vaccines, oncolytic viruses, adoptive cell therapy and combinations of immune checkpoint inhibitors with other agents are currently under investigation and may improve prognosis. Efforts to find robust biomarkers for response are also ongoing. In this review, we discuss the rationale for the use of immunotherapy in CCA and available clinical data. Ongoing trials will also be presented, as well as key findings from each study.

Immunotherapy in Advanced Biliary Tract Cancers

Biliary tract cancers are rare tumors with a poor prognosis. Two-thirds of these primary liver malignancies are diagnosed at advanced stages where therapeutic options are limited. Whereas several molecular targeted therapies emerge in biliary tract cancers, immunotherapy is still investigational, the only approved immunotherapy to date being the immune checkpoint inhibitor pembrolizumab for the small fraction of patients with microsatellite-instable tumors. In microsatellite-stable, pre-treated biliary tract cancers, single-agent immune checkpoint blockade has a limited albeit often long-lasting clinical activity in a still ill-defined subgroup of patients. The identification of predictive biomarkers will allow a better selection of patients that may benefit from immunotherapy. Combinations of immunotherapies with each other, with chemotherapy or targeted molecular therapies are being investigated in early lines of therapy, including first-line.