Targeting tumor-infiltrating tregs for improved antitumor responses

Immunotherapies have revolutionized the landscape of cancer treatment. Regulatory T cells (Tregs), as crucial components of the tumor immune environment, has great therapeutic potential. However, nonspecific inhibition of Tregs in therapies may not lead to enhanced antitumor responses, but could also trigger autoimmune reactions in patients, resulting in intolerable treatment side effects. Hence, the precision targeting and inhibition of tumor-infiltrating Tregs is of paramount importance. In this overview, we summarize the characteristics and subpopulations of Tregs within tumor microenvironment and their inhibitory mechanisms in antitumor responses. Furthermore, we discuss the current major strategies targeting regulatory T cells, weighing their advantages and limitations, and summarize representative clinical trials targeting Tregs in cancer treatment. We believe that developing therapies that specifically target and suppress tumor-infiltrating Tregs holds great promise for advancing immune-based therapies.

A Comprehensive Narrative Review on the History, Current Landscape, and Future Directions of Hepatocellular Carcinoma (HCC) Systemic Therapy

We provide a comprehensive review of current approved systemic treatment strategies for advanced hepatocellular carcinoma (HCC), starting with the phase III clinical trial of sorafenib which was the first to definitively show a survival benefit. After this trial, there was an initial period of little progress. However, in recent years, an explosion of new agents and combinations of agents has resulted in a markedly improved outlook for patients. We then provide the authors' current approach to therapy, i.e., "How We Treat HCC". Promising future directions and important gaps in therapy that persist are finally reviewed. HCC is a highly prevalent cancer worldwide and the incidence is growing due not only to alcoholism, hepatitis B and C, but also to steatohepatitis. HCC, like renal cell carcinoma and melanoma, is a cancer largely resistant to chemotherapy but the advent of anti-angiogenic, targeted and immune therapies have improved survival for all of these cancers. We hope this review will heighten interest in the field of HCC therapies, provide a clear outline of the current data and strategy for treatment, and sensitize readers to new developments that are likely to emerge in the near future.

Immunotherapy for recurrent hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is presented frequently in late stages that are not amenable for curative treatment. Even for patients who can undergo resection for curative treatment of HCC, up to 50% recur. For patients who were not exposed to systemic therapy prior to recurrence, recurrence frequently cannot be subjected to curative therapy or local treatments. Such patients have several options of immunotherapy (IO). This includes programmed cell death protein 1 (PD-1) and cytotoxic T- lymphocyte associated protein 4 treatment, combination of PD-1 and vascular endothelial growth factor inhibitor or single agent PD-1 therapy when all other options are deemed inappropriate. There are also investigational therapies in this area that explore either PD-1 and tyrosine kinase inhibitors or a novel agent in addition to PD-1 with vascular endothelial growth factor inhibitors. This mini-review explored IO options for patients with recurrent HCC who were not exposed to systemic therapy at the initial diagnosis. We also discussed potential IO options for patients with recurrent HCC who were exposed to first-line therapy with curative intent at diagnosis.

TKIs in combination with immunotherapy for hepatocellular carcinoma

INTRODUCTION

The treatment landscape of hepatocellular carcinoma (HCC) has significantly changed over the last 5 years with multiple options in the frontline, second line, and beyond. Tyrosine kinase inhibitors (TKIs) were the first approved systemic treatments for the advanced stage of HCC; however, thanks to the increasing knowledge and characterization of the immunological features of the tumor microenvironment, the systemic treatment of HCC has been further expanded with the immune checkpoint inhibitor (ICI) approach and the following evidence of the higher efficacy obtained with combined treatment with atezolizumab plus bevacizumab over sorafenib.

AREAS COVERED

In this review, we look at rationale, efficacy, and safety profiles of current and emerging ICI/TKI combination treatments and discuss the available results from other clinical trials using similar combinatorial therapeutic approaches.

EXPERT OPINION

Angiogenesis and immune evasion are the two key pathogenic hallmarks of HCC. While the pioneering regimen of atezolizumab/bevacizumab is consolidating as the first-line treatment of advanced HCC, it will be essential, in the near future, to determine the best second-line treatment options and how to optimize the selection of the most effective therapies. These points still need to be addressed by future studies that are largely warranted to enhance the treatment's effectiveness and ultimately to tackle down HCC lethality.

Immunotherapy for hepatocellular carcinoma: Current status and future perspectives

Hepatocellular carcinoma (HCC) is one of the world’s deadliest and fastest-growing tumors, with a poor prognosis. HCC develops in the context of chronic liver disease. Curative resection, surgery (liver transplantation), trans-arterial chemoembolization, radioembolization, radiofrequency ablation and chemotherapy are common treatment options for HCC, however, they will only assist a limited percentage of patients. Current treatments for advanced HCC are ineffective and aggravate the underlying liver condition. Despite promising preclinical and early-phase clinical trials for some drugs, existing systemic therapeutic methods for advanced tumor stages remain limited, underlining an unmet clinical need. In current years, cancer immunotherapy has made significant progress, opening up new treatment options for HCC. HCC, on the other hand, has a variety of causes and can affects the body’s immune system via a variety of mechanisms. With the speedy advancement of synthetic biology and genetic engineering, a range of innovative immunotherapies, such as immune checkpoint inhibitors [anti-programmed cell death-1 (PD-1), anti-cytotoxic T lymphocyte antigen-4, and anti-PD ligand 1 cell death antibodies], therapeutic cancer vaccines, engineered cytokines, and adoptive cell therapy have all been used for the treatment of advanced HCC. In this review, we summarize the present clinical and preclinical landscape of immunotherapies in HCC, critically discuss recent clinical trial outcomes, and address future perspectives in the field of liver cancer.

Hepatic failure associated with immune checkpoint inhibitors: An analysis of the Food and Drug Administration Adverse Event Reporting System database

BACKGROUND

Hepatic failure induced by immune checkpoint inhibitors (ICIs) has been reported in only a few case series and case reports.

OBJECTIVE

We aimed to explore the association between ICIs and hepatic failure and characterize the clinical features of ICI-associated hepatic failure in the pharmacovigilance database.

METHODS

Data from the first quarter (Q1) of 2015 to the fourth quarter (Q4) of 2021 in the US Food and Drug Administration Adverse Event Reporting System (FAERS) database were retrieved for disproportionality and Bayesian analysis. Reporting odds ratios (ROR) and information component (IC) were used to evaluate correlations between ICIs and hepatic failure.

RESULTS

Hepatic failure occurred in 0.19% (18,454/9,647,655) of all cases in the FAERS database, of which 654 cases were associated with ICIs. The overall median time from ICIs initiation to hepatic failure onset was 38 days, 72.3% of the adverse events occurred within the first 3 months, and 68.65% of the cases died after developing hepatic failure. In general, a strong signal was shown between ICIs and hepatic failure (ROR₀₂₅  = 2.70, IC₀₂₅  = 1.39). For the three categories of ICIs, programmed cell death 1 ligand 1 inhibitors (ROR₀₂₅  = 3.09, IC₀₂₅  = 1.57) had a higher risk signal than programmed cell death protein 1 inhibitors and cytotoxic T lymphocyte-associated protein 4 inhibitors. For monotherapy, atezolizumab showed the strongest risk signal (ROR₀₂₅  = 4.07, IC₀₂₅  = 1.90). The combination of nivolumab and ipilimumab showed stronger signals of hepatic failure compared with nivolumab or ipilimumab alone (nivolumab + ipilimumab vs. ipilimumab: ROR₀₂₅  = 1.40, IC₀₂₅  = 0.16; nivolumab + ipilimumab vs. nivolumab: ROR₀₂₅  = 1.24, IC₀₂₅  = 0.34). Considering the concomitant agents used with ICIs, the majority of these regimens showed stronger signals than ICI monotherapy, such as acetaminophen (ICIs + acetaminophen vs. ICIs: ROR₀₂₅  = 1.06, IC₀₂₅  = 0.32).

CONCLUSIONS

ICIs had possible strong signals associated with hepatic failure, and most cases of hepatic failure occurred within the first 3 months and had poor outcomes, which should attract clinical attention.

Network Analysis for the Discovery of Common Oncogenic Biomarkers in Liver Cancer Experimental Models

Hepatocellular carcinoma (HCC) is a malignancy marked by heterogeneity. This study aimed to discover target molecules for potential therapeutic efficacy that may encompass HCC heterogeneity. In silico analysis using published datasets identified 16 proto-oncogenes as potential pharmacological targets. We used an immortalized hepatocyte (IHH) and five HCC cell lines under two subtypes: S1/TGFβ-Wnt-activated (HLE, HLF, and JHH6) and the S2/progenitor subtype (HepG2 and Huh7). Three treatment modalities, 5 µM 5-Azacytidine, 50 µM Sorafenib, and 20 nM PD-L1 gene silencing, were evaluated in vitro. The effect of treatments on the proto-oncogene targets was assessed by gene expression and Western blot analysis. Our results showed that 10/16 targets were upregulated in HCC cells, where cells belonging to the S2/progenitor subtype had more upregulated targets compared to the S1/TGFβ-Wnt-activated subtype (81% vs. 62%, respectively). Among the targets, FGR was consistently down-regulated in the cell lines following the three different treatments. Sorafenib was effective to down-regulate targets in S2/progenitor subtype while PD-L1 silencing was able to decrease targets in all HCC subtypes, suggesting that this treatment strategy may comprise cellular heterogeneity. This study strengthens the relevance of liver cancer cellular heterogeneity in response to cancer therapies.

Prediction of early treatment response to the combination therapy of TACE plus lenvatinib and anti-PD-1 antibody immunotherapy for unresectable hepatocellular carcinoma: Multicenter retrospective study

Background and aim

The purpose of this study was to investigate and validate the efficacy of a nomogram model in predicting early objective response rate (ORR) in u-HCC patients receiving a combination of TACE, Lenvatinib, and anti-PD-1 antibody treatment after 3 months (triple therapy).

Method

This study included 169 u-HCC cases from five different hospitals. As training cohorts (n = 102), cases from two major centers were used, and external validation cohorts (n = 67) were drawn from the other three centers. The clinical data and contrast-enhanced MRI characteristics of patients were included in this retrospective study. For evaluating MRI treatment responses, the modified revaluation criteria in solid tumors (mRECIST) were used. Univariate and multivariate logistic regression analyses were used to select relevant variables and develop a nomogram model. Our as-constructed nomogram was highly consistent and clinically useful, as confirmed by the calibration curve and decision curve analysis (DCA); an independent external cohort also calibrated the nomogram.

Results

The ORR was 60.7% and the risk of early ORR was independently predicted by AFP, portal vein tumor thrombus (PVTT), tumor number, and size in both the training (C-index = 0.853) and test (C-index = 0.731) cohorts. The calibration curve revealed that the nomogram-predicted values were consistent with the actual response rates in both cohorts. Furthermore, DCA indicated that our developed nomogram performed well in clinical settings.

Conclusion

The nomogram model accurately predicts early ORR achieved by triple therapy in u-HCC patients, which aids in individual decision-making and modifying additional therapies for u-HCC cases.

Immune checkpoint and angiogenic inhibitors for the treatment of hepatocellular carcinoma: It takes two to tangle

Immunotherapy represents an effective and promising option in various cancers, including in hepatocellular carcinoma (HCC). The immune checkpoint inhibitors (ICIs) have shown a remarkable breakthrough in the last decade, in addition to molecular targeted therapy of angiogenesis such as tyrosine kinases inhibitors. ICIs provide new regimen that can be applied in different stages of the disease. In parallel, HCC progression is related to the tumor microenvironment (TME), involving the cross-talk between various cellular and non-cellular components within the TME niche. It appears logical to synergistically target several HCC components to increase the efficacy of the treatment. In this paper, we summarize evidence that the combination therapy of ICIs and angiogenesis inhibitors would be a potentially better strategy for HCC treatment.

DNA methylation regulators-related molecular patterns and tumor immune landscape in hepatocellular carcinoma

Increasing evidence showed that the dysregulation of DNA methylation regulators is a decisive feature of almost all cancer types and affects tumor progressions. However, few studies focused on the underlying influences of DNA methylation regulators-related genes (DMRegs) in immune cell-infiltration characteristics, tumor microenvironment (TME) and immunotherapy in HCC patients. In our study, the alterations of DNA methylation regulators modification patterns (DMRPs) were clustered from hepatocellular carcinoma (HCC) samples based on the expression of DNA methylation regulators as well as genetic and transcriptional features. In addition, based on molecular identification of three distinct molecular subtypes, we found that different DMRPs alterations were related to different clinicopathological characteristics, prognosis, and immune cells infiltration features. Moreover, we constructed and validated a DNA methylation regulators-related genes score (DMRegs_score) to predict the survival of HCC patients. A high DMRegs _score, which was characterized by more TP53 wild mutation, high expression of PD-1, CTLA-4, and remarkable immunity activation, was indicative of poor prognosis. Furthermore, we validated the expression of eight genes which were used for the prognostic signature in this risk score by RT-qPCR using tissues from our center. More importantly, DMRegs_score was highly correlated with targeted drug sensitivity. Additionally, we developed a highly accurate scoring system that could be used to improve the clinical applicability of DMRegs _score. In conclusion, these findings may contribute to a better understanding of DNA methylation regulators and provide new strategies for evaluating prognosis and developing more effective combination therapy for HCC patients.

Immune modulation by molecularly targeted photothermal ablation in a mouse model of advanced hepatocellular carcinoma and cirrhosis

Immunotherapy is a promising new treatment approach for hepatocellular carcinoma (HCC), but there are numerous barriers to immunotherapy in HCC, including an immunosuppressive microenvironment and the "immunotolerance" of the liver. Hyperthermia treatment modalities are standard of care for early stage HCC, and hyperthermia is known to have immunomodulatory effects. We have developed a molecularly targeted photothermal ablation (MTPA) technology that provides thermally tunable, tumor-specific heat generation. The purpose of this study was to evaluate the morphologic and immunologic effects of MTPA in an immunotherapy-resistant syngeneic mouse model of HCC in a background of toxin-induced cirrhosis. We found that the anatomic, cellular, and molecular features of this model recapitulate the characteristics of advanced human HCC. MTPA as a monotherapy and in combination with immune checkpoint therapy significantly increased intratumoral CD3+ and activated CD8+ T cells while decreasing regulatory T cells relative to control or immune checkpoint therapy alone based on immunohistochemistry, flow cytometry, and single cell RNA sequencing data. Furthermore, we identified evidence of MTPA's influence on systemic tumor immunity, with suppression of remote tumor growth following treatment of orthotopic tumors. The results of this study suggest that tumor-specific hyperthermia may help overcome resistance mechanisms to immunotherapy in advanced HCC.

A comprehensive review about the utilization of immune checkpoint inhibitors and combination therapy in hepatocellular carcinoma: an updated review

A pharmacological class known as immune checkpoint inhibitors (ICIs) has been developed as a potential treatment option for various malignancies, including HCC. In HCC, ICIs have demonstrated clinically significant advantages as monotherapy or combination therapy. ICIs that target programmed cell death protein 1 (PD-1) and programmed cell death protein ligand 1 (PD-L1), as well as cytotoxic T lymphocyte antigen 4 (CTLA-4), have made significant advances in cancer treatment. In hepatocellular carcinoma (HCC), several ICIs are being tested in clinical trials, and the area is quickly developing. As immunotherapy-related adverse events (irAEs) linked with ICI therapy expands and gain worldwide access, up-to-date management guidelines become crucial to the safety profile of ICIs. This review aims to describe the evidence for ICIs in treating HCC, emphasizing the use of combination ICIs.

Risk predictive model based on three immune-related gene pairs to assess prognosis and therapeutic sensitivity for hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) as a common tumor has a poor prognosis. Recently, a combination of atezolizumab and bevacizumab has been recommended as the preferred regimen for advanced HCC. However, the overall response rate of this therapy is low. There is an urgent need to identify sensitive individuals for this precise therapy among HCC patients.

METHODS

The Wilcox test was used to screen the differentially expressed immune-related genes by combining the TCGA cohort and the Immunology Database. Univariate and multivariate Cox regression analysis were used to screen the immune gene pairs concerning prognosis. A predictive model was constructed using LASSO Cox regression analysis, and correlation analysis was conducted between the signature and clinical characteristics. ICGC cohort and GSE14520 were applied for external validations of the predictive risk model. The relationship between immune cell infiltration, TMB, MSI, therapeutic sensitivity of immune checkpoint inhibitors, targeted drugs, and the risk model were assessed by bioinformatics analysis in HCC patients.

RESULTS

A risk predictive model consisting of 3 immune-related gene pairs was constructed and the risk score was proved as an independent prognostic factor for HCC patients combining the TCGA cohort. This predictive model exhibited a positive correlation with tumor size (p < 0.01) and tumor stage (TNM) (p < 0.001) in the chi-square test. The predictive power was verified by external validations (ICGC and GSE14520). The risk score clearly correlated with immune cell infiltration, MSI, immune checkpoints, and markers of angiogenesis.

CONCLUSIONS

Our research established a risk predictive model based on 3 immune-related gene pairs and explored its relationship with immune characteristics, which might help to assess the prognosis and treatment sensitivity to immune and targeted therapy of HCC patients.

Toxicity Profiles of Systemic Therapies for Advanced Hepatocellular Carcinoma: A Systematic Review and Meta-analysis

IMPORTANCE

The recent development of targeted therapy and immunotherapy has made neoadjuvant therapy an attractive option for patients with hepatocellular carcinoma (HCC). However, surgeons are concerned that adverse effects of neoadjuvant therapy with these agents could lead to delayed or even cancelled surgeries.

OBJECTIVE

To summarize the current evidence regarding toxicity profiles for tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) among patients with HCC.

DATA SOURCES

Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched from January 1990 and December 2021.

STUDY SELECTION

Single-group, placebo-controlled, and dual-agent clinical trials comparing TKIs and ICIs in patients with HCC were eligible for inclusion.

DATA EXTRACTION AND SYNTHESIS

Following the Preferred Reporting Items in Systematic Reviews and Meta-analysis guideline, 2 reviewers independently extracted data. A random-effects model was used.

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of patients with clinically significant liver-related adverse events. Secondary outcomes included the proportion of patients who experienced clinically relevant (grade 3 or higher) adverse events and significant adverse events (ie, those that were life threatening, required hospitalization, or prolonged disability) as well as the risk ratio (RR) of these complications.

RESULTS

Overall, 30 studies with 12 921 patients were included. Patients had a mean (range) age of 62 (18-89) years; a mean (SD) 84% (3) were male; a mean (SD) 82% (16) had Barcelona Clinic Liver Cancer stage C HCC; and a mean (SD) 97% (6) had Childs A cirrhosis. Overall, 21% (95% CI, 16%-26%) of patients receiving TKIs had liver toxic effects compared with 28% (95% CI, 21%-35%) of patients receiving ICIs. Severe adverse events occurred in 46% (95% CI, 40%-51%) of patients receiving TKIs compared with 24% (95% CI, 13%-35%) of patients receiving ICIs. Compared with patients receiving sorafenib, other TKIs were associated with similar rates of liver toxic effects (RR, 1.06; 95% CI, 0.92-1.24) but higher rates of severe adverse events (RR, 1.24; 95% CI, 1.07-1.44). Comparing ICIs with sorafenib, there were similar rates of liver toxic effects (RR, 1.10; 95% CI, 0.86-1.40) and severe adverse events (RR, 1.19; 95% CI, 0.95-1.50).

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis, serious adverse events were lower with ICIs than with TKIs, while liver toxic effects were similar. Combination therapy with novel ICIs is an appealing option in trials of neoadjuvant therapy for patients with HCC, requiring evaluation in preoperative trials.

Therapeutic Vaccines against Hepatocellular Carcinoma in the Immune Checkpoint Inhibitor Era: Time for Neoantigens?

Immune checkpoint inhibitors (ICI) have been used as immunotherapy for hepatocellular carcinoma (HCC) with promising but still limited results. Identification of immune elements in the tumor microenvironment of individual HCC patients may help to understand the correlations of responses, as well as to design personalized therapies for non-responder patients. Immune-enhancing strategies, such as vaccination, would complement ICI in those individuals with poorly infiltrated tumors. The prominent role of responses against mutated tumor antigens (neoAgs) in ICI-based therapies suggests that boosting responses against these epitopes may specifically target tumor cells. In this review we summarize clinical vaccination trials carried out in HCC, the available information on potentially immunogenic neoAgs in HCC patients, and the most recent results of neoAg-based vaccines in other tumors. Despite the low/intermediate mutational burden observed in HCC, data obtained from neoAg-based vaccines in other tumors indicate that vaccines directed against these tumor-specific antigens would complement ICI in a subset of HCC patients.

Nanomedicine in Hepatocellular Carcinoma: A New Frontier in Targeted Cancer Treatment

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death and is associated with a dismal median survival of 2-9 months. The fundamental limitations and ineffectiveness of current HCC treatments have led to the development of a vast range of nanotechnologies with the goal of improving the safety and efficacy of treatment for HCC. Although remarkable success has been achieved in nanomedicine research, there are unique considerations such as molecular heterogeneity and concomitant liver dysfunction that complicate the translation of nanotheranostics in HCC. This review highlights the progress, challenges, and targeting opportunities in HCC nanomedicine based on the growing literature in recent years.

Strategies to Improve the Antitumor Effect of Immunotherapy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), one of the most fatal malignancies in the world, is usually diagnosed in advanced stages due to late symptom manifestation with very limited therapeutic options, which leads to ineffective intervention and dismal prognosis. For a decade, tyrosine kinase inhibitors (TKIs) have offered an overall survival (OS) benefit when used in a first-line (sorafenib and lenvatinib) and second-line setting (regorafenib and cabozantinib) in advanced HCC, while long-term response remains unsatisfactory due to the onset of primary or acquired resistance. Recently, immunotherapy has emerged as a promising therapy in the treatment of several solid tumors, such as melanoma and non-small cell lung cancer. Moreover, as the occurrence of HCC is associated with immune tolerance and immunosurveillance escape, there is a potent rationale for employing immunotherapy in HCC. However, immunotherapy monotherapy, mainly including immune checkpoint inhibitors (ICIs) that target checkpoints programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), and the cytotoxic T lymphocyte antigen-4 (CTLA-4), has a relatively low response rate. Thus, the multi-ICIs or the combination of immunotherapy with other therapies, like antiangiogenic drugs and locoregional therapies, has become a novel strategy to treat HCC. Combining different ICIs may have a synergistical effect attributed to the complementary effects of the two immune checkpoint pathways (CTLA-4 and PD-1/PD-L1 pathways). The incorporation of antiangiogenic drugs in ICIs can enhance antitumor immune responses via synergistically regulating the vasculature and the immune microenvironment of tumor. In addition, locoregional treatments can improve antitumor immunity by releasing the neoplasm antigens from killed tumor cells; in turn, this antitumor immune response can be intensified by immunotherapy. Therefore, the combination of locoregional treatments and immunotherapy may achieve greater efficacy through further synergistic effects for advanced HCC. This review aims to summarize the currently reported results and ongoing trials of the ICIs-based combination therapies for HCC to explore the rational combination strategies and further improve the survival of patients with HCC.

Programmed Cell Death 1 and Hepatocellular Carcinoma: An Epochal Story

In recent years, immune-based therapies have emerged as novel pillars for hepatocellular carcinoma (HCC). The rationale of immune-checkpoint inhibitors (ICIs) trial in HCC originated from the fact that the tumor cells and the infiltrating stromal and immune cells promote an immunosuppressive tumor microenvironment, including the up-regulation of immune checkpoint molecules on their surface. Antibody-based blockage targeting inhibitory checkpoint molecules on cytotoxic T cells, including programmed cell death-1 (PD-1) or its counterpart on antigen-presenting cells has shown strong anti-tumor activity in a subset of HCC patients. Single nucleotide polymorphisms (SNP) of PD-1 gene may affect the PD-1 expression or function, which eventually can cause dysfunctionality of immune balance. Based on the inhibitory role of PD-1 in anti-tumor responses, it has been investigated in several studies as a candidate to test for genetic susceptibility of individuals to HCC. The present paper highlights the knowledge on cross-talks for liver immunology and HCC course, recent studies investigating the role of functional SNPs of PD-1 gene in Turkish HCC population, and the data on already investigated PD-1 inhibitor molecules in clinical trials.

Immunotherapeutic treatments in hepatocellular carcinoma; achievements, challenges and future prospects

Hepatocellular carcinoma (HCC) is one of the most common and fatal malignancies with an alarming trend all around the world. Common therapeutic approaches in the early stage of disease are surgical resection, ablation, and liver transplantation. Due to the insidious identity of HCC, the majority of the patients are diagnosed at advanced stages, where tumor spreading, or distant metastasis unfortunately have already occurred. Immunotherapeutic options have elicited a promising approach in some malignancies with Food and Drug Administration (FDA) approving the first checkpoint inhibitor anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) ipilimumab for the treatment of melanoma ten years ago. In the past decade, many clinical trials have been investigating anti-CTLA-4 as well as anti-programmed cell death protein 1 (PD-1) therapies in various solid tumors, including HCC. In this mini-review we will discuss the latest clinical data from clinical trials for immune-checkpoint inhibitors for the treatment of HCC.

Cure the Incurable? Recent Breakthroughs in Immune Checkpoint Blockade for Hepatocellular Carcinoma

HCC usually arises from a chronic inflammation background, driven by several factors including fatty liver, HBV/HCV viral infection and metabolic syndrome. Systemic treatment for advanced HCC remains disappointing due to its strong resistance to chemotherapy and even to tyrosine kinase inhibitors (TKIs). Recently, the use of ICI therapy has revolutionized the systemic treatment of advanced HCC. For the first time, clinical trials testing ICIs, anti-CTLA-4 and anti-PD1/PDL1 reported a survival benefit in patients with sorafenib resistance. However, it took four more years to find the right combination regimen to use ICI in combination with the anti-angiogenic agent bevacizumab to substantially prolong overall survival (OS) of patients with advanced HCC after sorafenib. This review provides a comprehensive history of ICI therapy in HCC, up-to-date information on the latest ICI clinical trials, and discusses the recent development of novel ICIs that would potentially lead to a new checkpoint blockade therapy for advanced HCC.

Advances in immunotherapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a prevalent disease with a progression that is modulated by the immune system. Systemic therapy is used in the advanced stage and until 2017 consisted only of antiangiogenic tyrosine kinase inhibitors (TKIs). Immunotherapy with checkpoint inhibitors has shown strong anti-tumour activity in a subset of patients and the combination of the anti-PDL1 antibody atezolizumab and the VEGF-neutralizing antibody bevacizumab has or will soon become the standard of care as a first-line therapy for HCC, whereas the anti-PD1 agents nivolumab and pembrolizumab are used after TKIs in several regions. Other immune strategies such as adoptive T-cell transfer, vaccination or virotherapy have not yet demonstrated consistent clinical activity. Major unmet challenges in HCC checkpoint immunotherapy are the discovery and validation of predictive biomarkers, advancing treatment to earlier stages of the disease, applying the treatment to patients with liver dysfunction and the discovery of more effective combinatorial or sequential approaches. Combinations with other systemic or local treatments are perceived as the most promising opportunities in HCC and some are already under evaluation in large-scale clinical trials. This Review provides up-to-date information on the best use of currently available immunotherapies in HCC and the therapeutic strategies under development.

Immunotherapy in hepatocellular carcinoma: evaluation and management of adverse events associated with atezolizumab plus bevacizumab

In light of positive efficacy and safety findings from the IMbrave150 trial of atezolizumab plus bevacizumab, this novel combination has become the preferred first-line standard of care for patients with unresectable hepatocellular carcinoma (HCC). Several additional trials are ongoing that combine an immune checkpoint inhibitor with another agent such as a multiple kinase inhibitor or antiangiogenic agent. Therefore, the range of first-line treatment options for unresectable HCC is likely to increase, and healthcare providers need succinct information about the use of such combinations, including their efficacy and key aspects of their safety profiles. Here, we review efficacy and safety data on combination immunotherapies and offer guidance on monitoring and managing adverse events, especially those associated with atezolizumab plus bevacizumab. Because of their underlying liver disease and high likelihood of portal hypertension, patients with unresectable HCC are at particular risk of gastrointestinal bleeding, and this risk may be exacerbated by treatments that include antiangiogenic agents. Healthcare providers also need to be alert to the risks of proteinuria and hypertension, colitis, hepatitis, and reactivation of hepatitis B or C virus infection. They should also be aware of the possibility of rarer but potentially life-threatening adverse events such as pneumonitis and cardiovascular events. Awareness of the risks associated with these therapies and knowledge of adverse event monitoring and management will become increasingly important as the therapeutic range broadens in unresectable HCC.

Immunotherapy against programmed death-1/programmed death ligand 1 in hepatocellular carcinoma: Importance of molecular variations, cellular heterogeneity, and cancer stem cells

Hepatocellular carcinoma (HCC) is a heterogeneous malignancy related to diverse etiological factors. Different oncogenic mechanisms and genetic variations lead to multiple HCC molecular classifications. Recently, an immune-based strategy using immune checkpoint inhibitors (ICIs) was presented in HCC therapy, especially with ICIs against the programmed death-1 (PD-1) and its ligand PD-L1. However, despite the success of anti-PD-1/PD-L1 in other cancers, a substantial proportion of HCC patients fail to respond. In this review, we gather current information on biomarkers of anti-PD-1/PD-L1 treatment and the contribution of HCC heterogeneity and hepatic cancer stem cells (CSCs). Genetic variations of PD-1 and PD-L1 are associated with chronic liver disease and progression to cancer. PD-L1 expression in tumoral tissues is differentially expressed in CSCs, particularly in those with a close association with the tumor microenvironment. This information will be beneficial for the selection of patients and the management of the ICIs against PD-1/PD-L1.

Prospects and Challenges for T Cell-Based Therapies of HCC

The scope of therapeutic options for the treatment of hepatocellular carcinoma (HCC) has recently been expanded by immunotherapeutic regimens. T cell-based therapies, especially in combination with other treatments have achieved far better outcomes compared to conventional treatments alone. However, there is an emerging body of evidence that eliciting T cell responses in immunotherapeutic approaches is insufficient for favorable outcomes. Immune responses in HCC are frequently attenuated in the tumor microenvironment (TME) or may even support tumor progress. Hence, therapies with immune checkpoint inhibitors or adoptive cell therapies appear to necessitate additional modification of the TME to unlock their full potential. In this review, we focus on immunotherapeutic strategies, underlying molecular mechanisms of CD8 T cell immunity, and causes of treatment failure in HCC of viral and non-viral origin. Furthermore, we provide an overview of TME features in underlying etiologies of HCC patients that mediate therapy resistance to checkpoint inhibition and discuss strategies from the literature concerning current approaches to these challenges.

Research Progresses of Targeted Therapy and Immunotherapy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide, with nearly one million new cases and deaths every year. Owing to the complex pathogenesis, hidden early symptoms, rapidly developing processes, and poor prognosis, the morbidity and mortality of HCC are increasing yearly. With the progress being made in modern medicine, the treatment of HCC is no longer limited to traditional methods. Targeted therapy and immunotherapy have emerged to treat advanced and metastatic HCC in recent years. Since Sorafenib is the first molecular targeting drug against angiogenesis, targeted drugs for HCC are continually emerging. Moreover, immunotherapy plays a vital role in clinical trials. In particular, the application of immune checkpoint inhibitors, which have received increasing attention in the field of cancer treatment, is a possible research path. Interestingly, these two therapies generally complement each other at some stages of HCC, bringing new hope for patients with advanced HCC. In this paper, we discuss the research progress of targeted therapy and immunotherapy for HCC in recent years, which will provide a reference for the further development of drugs for HCC.

Advances in immunotherapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a prevalent disease with a progression that is modulated by the immune system. Systemic therapy is used in the advanced stage and until 2017 consisted only of antiangiogenic tyrosine kinase inhibitors (TKIs). Immunotherapy with checkpoint inhibitors has shown strong anti-tumour activity in a subset of patients and the combination of the anti-PDL1 antibody atezolizumab and the VEGF-neutralizing antibody bevacizumab has or will soon become the standard of care as a first-line therapy for HCC, whereas the anti-PD1 agents nivolumab and pembrolizumab are used after TKIs in several regions. Other immune strategies such as adoptive T-cell transfer, vaccination or virotherapy have not yet demonstrated consistent clinical activity. Major unmet challenges in HCC checkpoint immunotherapy are the discovery and validation of predictive biomarkers, advancing treatment to earlier stages of the disease, applying the treatment to patients with liver dysfunction and the discovery of more effective combinatorial or sequential approaches. Combinations with other systemic or local treatments are perceived as the most promising opportunities in HCC and some are already under evaluation in large-scale clinical trials. This Review provides up-to-date information on the best use of currently available immunotherapies in HCC and the therapeutic strategies under development.

Immunotherapy and Targeted Therapy for Hepatocellular Carcinoma: A Literature Review and Treatment Perspectives

Advanced hepatocellular carcinoma is a prevalent and potentially aggressive disease. For more than a decade, treatment with sorafenib has been the only approved therapeutic approach. Moreover, no agent has been proven to prolong survival following the progression of disease after sorafenib treatment. However, in recent years, this scenario has changed substantially with several trials being conducted to examine the effects of immunotherapy and novel targeting agents. Several immune checkpoint inhibitors have shown promising results in early-stage clinical trials. Moreover, phase III trials with large cohorts have demonstrated remarkable improvement in survival with the use of new targeted therapies in second-line treatment. Treatment regimens involving the combination of two immune checkpoint inhibitors as well as immune checkpoint inhibitors and anti-angiogenic targeted therapies have shown potential to act synergistically in clinical trials. Recently, the combination of atezolizumab and bevacizumab evaluated in a phase III clinical trial has demonstrated survival superiority in the first-line treatment; it is the new considered standard of care. In this manuscript, we aimed to review the latest advances in the systemic treatment of advanced hepatocellular carcinoma focusing on immunotherapy and targeted therapies.

Augmenting Anticancer Immunity Through Combined Targeting of Angiogenic and PD-1/PD-L1 Pathways: Challenges and Opportunities

Cancer immunotherapy (CIT) with antibodies targeting the programmed cell death 1 protein (PD-1)/programmed cell death 1 ligand 1 (PD-L1) axis have changed the standard of care in multiple cancers. However, durable antitumor responses have been observed in only a minority of patients, indicating the presence of other inhibitory mechanisms that act to restrain anticancer immunity. Therefore, new therapeutic strategies targeted against other immune suppressive mechanisms are needed to enhance anticancer immunity and maximize the clinical benefit of CIT in patients who are resistant to immune checkpoint inhibition. Preclinical and clinical studies have identified abnormalities in the tumor microenvironment (TME) that can negatively impact the efficacy of PD-1/PD-L1 blockade. Angiogenic factors such as vascular endothelial growth factor (VEGF) drive immunosuppression in the TME by inducing vascular abnormalities, suppressing antigen presentation and immune effector cells, or augmenting the immune suppressive activity of regulatory T cells, myeloid-derived suppressor cells, and tumor-associated macrophages. In turn, immunosuppressive cells can drive angiogenesis, thereby creating a vicious cycle of suppressed antitumor immunity. VEGF-mediated immune suppression in the TME and its negative impact on the efficacy of CIT provide a therapeutic rationale to combine PD-1/PD-L1 antibodies with anti-VEGF drugs in order to normalize the TME. A multitude of clinical trials have been initiated to evaluate combinations of a PD-1/PD-L1 antibody with an anti-VEGF in a variety of cancers. Recently, the positive results from five Phase III studies in non-small cell lung cancer (adenocarcinoma), renal cell carcinoma, and hepatocellular carcinoma have shown that combinations of PD-1/PD-L1 antibodies and anti-VEGF agents significantly improved clinical outcomes compared with respective standards of care. Such combinations have been approved by health authorities and are now standard treatment options for renal cell carcinoma, non-small cell lung cancer, and hepatocellular carcinoma. A plethora of other randomized studies of similar combinations are currently ongoing. Here, we discuss the principle mechanisms of VEGF-mediated immunosuppression studied in preclinical models or as part of translational clinical studies. We also discuss data from recently reported randomized clinical trials. Finally, we discuss how these concepts and approaches can be further incorporated into clinical practice to improve immunotherapy outcomes for patients with cancer.

Immuno-oncology for Hepatocellular Carcinoma: The Present and the Future

Hepatocellular carcinoma is a highly prevalent and lethal cancer that many therapeutics are being tested for this disease. It has the potential to be a highly immune-responsive tumor given its inflammatory origins. The first immunotherapies were anti-programmed death-1 monotherapies, which improved response rates and survival. Novel immunotherapy combinations and immunotherapy show promise in frontline treatment. The novel antibody therapy combination of atezolizumab and bevacizumab may be practice changing. Although these landmark studies seem to offer new treatment options, the role of immunotherapy in the liver transplant setting is uncertain until the safety of this approach is defined.

Immunotherapy for Hepatocellular Carcinoma: A 2021 Update

Hepatocellular carcinoma (HCC) is one of one of the most frequent liver cancers and the fourth leading cause of cancer-related mortality worldwide. Current treatment options such as surgery, neoadjuvant chemoradiotherapy, liver transplantation, and radiofrequency ablation will benefit only a very small percentage of patients. Immunotherapy is a novel treatment approach representing an effective and promising option against several types of cancer. The aim of our study is to present the currently ongoing clinical trials and to evaluate the efficacy of immunotherapy in HCC. In this paper, we demonstrate that combination of different immunotherapies or immunotherapy with other modalities results in better overall survival (OS) and progression-free survival (PFS) compared to single immunotherapy agent. Another objective of this paper is to demonstrate and highlight the importance of tumor microenvironment as a predictive and prognostic marker and its clinical implications in immunotherapy response.

Phase II study of atezolizumab in combination with bevacizumab in patients with advanced cervical cancer

Background

There are limited treatment options for patients with metastatic or recurrent cervical cancer. Platinum-based chemotherapy plus the anti-vascular endothelial growth factor antibody bevacizumab remains the mainstay of advanced treatment. Pembrolizumab is Food and Drug Agency approved for programmed death ligand 1 (PD-L1) positive cervical cancer with a modest response rate. This is the first study to report the efficacy and safety of the PD-L1 antibody atezolizumab in combination with bevacizumab in advanced cervical cancer.

Methods

We report the results from a phase II, open-label, multicenter study (NCT02921269). Patients with advanced cervical cancer were treated with bevacizumab 15 mg/kg intravenous every 3 weeks and atezolizumab 1200 mg intravenous every 3 weeks. The primary objective was to measure the objective response rate (ORR). Secondary endpoints included disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety.

Results

In the total evaluable population (n=10), zero patients achieved an objective response as assessed by Response Evaluation Criteria In Solid Tumors (RECIST) V.1.1, resulting in a confirmed ORR of 0%. Of note, there were two patients who achieved an unconfirmed PR. The DCR by RECIST V.1.1 was 60% (0% complete response, 0% partial response, 60% stable disease). Median PFS was 2.9 months (95% CI, 1.8 to 6) and median OS was 8.9 months (95% CI, 3.4 to 21.9). Safety results were generally consistent with the known safety profile of both drugs, notably with two high-grade neurologic events.

Conclusions

The combination of bevacizumab and atezolizumab did not meet the predefined efficacy endpoint, as addition of bevacizumab to PD-L1 blockade did not appear to enhance the ORR in cervical cancer.

[Immuno-oncology : No longer a need for interventional radiology?]

CLINICAL ISSUE

Hepatocellular carcinoma (HCC) is associated with a high mortality rate.

STANDARD TREATMENT

For many years, sorafenib was the only, and frequently poorly tolerated systemic treatment option, which lead to the unreflected recurrent use of locoregional treatment modalities, such as transarterial chemoembolization (TACE).

INNOVATIONS

Based on recent positive phase III trial results, we now have three systemic therapeutic options available in the first and second line of treatment, respectively. This development enables us to design sequential treatments concepts for patients with advanced HCC.

DIAGNOSTIC WORK-UP

Beyond the assessment of tumor burden, the liver function of HCC patients needs to be closely monitored under therapy.

PERFORMANCE

High response rates, including complete remissions have been documented for immuno-oncology-based combination regimens in HCC patients. Already today, a median overall survival (mOS) above 20 months can been achieved through the sequential application of systemic therapies in phase II studies in patients with advanced HCC and preserved liver function.

ACHIEVEMENTS

Local therapies will remain an integral component of HCC therapy. However, recent advancements will shift the focus towards systemic treatment concepts.

PRACTICAL RECOMMENDATIONS

The rigorous implementation of validated scoring systems can contribute towards an improved selection of patients that are suited to locoregional therapies. Longitudinal monitoring of liver function is fundamental to ensure that the optimal point in time for a switch towards systemic therapies is not missed.

The cost-effectiveness of TheraSphere in patients with hepatocellular carcinoma who are eligible for transarterial embolization

INTRODUCTION

The aim of the study is to estimate the cost-effectiveness of TheraSphere against other embolic treatments in a population with early to intermediate stage hepatocellular carcinoma (HCC) who are unresectable at presentation and are eligible for transarterial embolization (TAE), conventional transarterial chemoembolization (cTACE) or drug-eluting bead TACE (DEB-TACE).

MATERIALS AND METHODS

A Markov model was constructed using a UK National Health Service (NHS) perspective, a 20-year time horizon, and four-week cycles. The eight health states included 'watch and wait', 'transplantation' (pre-, post and post (No HCC)), 'resection', 'no HCC other', 'pharmacological management' and 'death'. Clinical data were sourced from literature and expert opinion. Resource use and costs were reflective of the NHS, and benefits were quantified using Quality-Adjusted Life Years (QALYs), with utility weights sourced from literature. Comparators were TAE, cTACE and DEB-TACE. The primary output was the Incremental Cost-Effectiveness Ratio (ICER) expressed as cost per QALY gained. An ICER of under £20,000/QALY gained for an intervention is cost-effective and represents efficient use of healthcare resources. Extensive deterministic and probabilistic sensitivity analyses were undertaken.

RESULTS

TheraSphere patients were predicted to gain 0.7 additional QALYs compared to all other treatments. The base case ICERs for TheraSphere were £17,300, £17,279 and £23,020 per QALY gained compared to TAE, cTACE and DEB-TACE, respectively. In the TheraSphere cohort, 87% more patients were predicted to achieve downstaging compared to all other treatment options.

CONCLUSIONS

This study indicates that treatment with TheraSphere is a potentially cost-effective option for patients with early to intermediate stage HCC.

Safety and Clinical Activity of Atezolizumab Plus Bevacizumab in Patients with Ovarian Cancer: A Phase Ib Study

PURPOSE

Atezolizumab has shown antitumor activity in patients with ovarian cancer. Dual blockade of programmed death-ligand 1 (PD-L1) and VEGF enhances anticancer immunity and augments antitumor activity in several cancers. The safety and efficacy of atezolizumab plus bevacizumab were evaluated in patients with ovarian cancer.

PATIENTS AND METHODS

In this open-label, multicenter phase Ib study, patients with platinum-resistant ovarian cancer received intravenous atezolizumab (1,200 mg) and bevacizumab (15 mg/kg) once every 3 weeks. The primary endpoint was safety; secondary endpoints included overall response rate (ORR), duration of response (DOR), progression-free survival (PFS), and overall survival (OS). Exploratory biomarkers were also evaluated.

RESULTS

Twenty patients received treatment. Treatment-related adverse events occurred in 19 patients (95%); seven (35%) had grade 3/4 events. No grade 5 events occurred. The safety profile of atezolizumab plus bevacizumab was consistent with those of the individual agents. Two patients (10%) discontinued treatment because of pneumonitis and small bowel obstruction. Three patients had partial responses of 11.3-18.9 months' duration; the ORR was 15%. Eight patients (40%) had stable disease, hence the disease control rate was 55%. The median DOR was not reached (95% confidence interval, 11.3-not reached). Median PFS was 4.9 months (range, 1.2-20.2); median OS was 10.2 months (range, 1.2-26.6). No association was seen between treatment response and PD-L1 expression, tumor histology, or number of prior therapies.

CONCLUSIONS

Atezolizumab plus bevacizumab led to durable responses and/or disease stabilization in some patients with platinum-resistant ovarian cancer; the safety profiles were consistent with those of each agent.

Immunotherapy in hepatocellular carcinoma: Combination strategies

Liver cancer is one of the most common causes of cancer death globally, and its incidence in the United States is increasing. Patients with advanced hepatocellular carcinoma (HCC) who are not candidates for surgical resection, liver transplant, or locoregional therapies can be treated with systemic therapies. Multiple agents, including sorafenib, lenvatinib, and regorafenib are approved for use as either first- or second-line therapy in this patient population, but all have relatively modest survival benefits. HCC is potentially susceptible to therapy with checkpoint inhibitors, including agents such as nivolumab and pembrolizumab, which are both approved by the Food and Drug Administration for patients previously treated with sorafenib but have not demonstrated superior overall survival in phase III trials. It is clear that more effective approaches are needed to potentiate the effects of checkpoint inhibitors in patients with HCC. This review will outline and appraise the current literature on the use of checkpoint inhibitors in HCC as part of a combination treatment involving an additional mode of therapy. The list of agents that can be paired with checkpoint inhibitors includes an additional checkpoint inhibitor, vascular endothelial growth factor or vascular endothelial growth factor receptor inhibitors, tyrosine kinase inhibitors, OX-40 agonists, and PT-112 inhibitors. The main non-pharmacologic therapies currently being studied for inclusion in a combination strategy include radiation therapy, trans-arterial chemoembolization, and ablation.

Management and Treatment of Hepatocellular Carcinoma with Immunotherapy: A Review of Current and Future Options

With mortality rates of liver cancer doubling in the last 20 years, this disease is on the rise and has become the fifth most common cancer in men and the seventh most common cancer in women. Hepatocellular carcinoma (HCC) represents approximately 90% of all primary liver cancers and is a major global health concern. Patients with HCC can be managed curatively with surgical resection or with liver transplantation, if they are diagnosed at an early stage. Unfortunately, most patients with HCC present with advanced stages of the disease and have underlying liver dysfunction, which allows only 15% of patients to be eligible for curative treatment. Several different treatment modalities are available, including locoregional therapy radiofrequency ablation, microwave ablation, percutaneous ethanol injection, trans-arterial chemoembolization, transarterial radio-embolization, cryoablation, radiation therapy, stereotactic radiotherapy, systemic chemotherapy, molecularly targeted therapies, and immunotherapy. Immunotherapy has recently become a promising method for inhibiting HCC tumor progression, recurrence, and metastasis. The term "Immunotherapy" is a catch-all, encompassing a wide range of applications and targets, including HCC vaccines, adoptive cell therapy, immune checkpoint inhibitors, and use of oncolytic viruses to treat HCC. Immunotherapy in HCC is a relatively safe option for treating patients with advanced disease in the USA who are either unable to receive or failed sorafenib/lenvatinib therapy and thus may offer an additional survival benefit for these patients. The purpose of this review is to elaborate on some of the most recent advancements in immunotherapy.

Ramucirumab, A Second-Line Option For Patients With Hepatocellular Carcinoma: A Review Of The Evidence

Hepatocellular carcinoma (HCC) is the most frequent primary liver cancer and predominantly develops in patients with liver cirrhosis. In patients with advanced disease, such as extra-hepatic extension or portal vein involvement, and with intermediate disease unsuitable for locoregional therapies, systemic therapy is recommended, if liver function and performance status are adequate. Following a decade of negative Phase III trials since the approval of sorafenib, more recently several drugs have proven efficacy both in first line versus sorafenib (lenvatinib) or in second line versus placebo (regorafenib, cabozantinib, ramucirumab). In this review, we summarize the preclinical and clinical evidence supporting the use of ramucirumab, a recombinant IgG1 monoclonal antibody that specifically binds to Vascular Endothelial Growth Factor receptor 2 (VEGFR-2), in HCC. Following the results of the REACH trial, that was negative in the overall study population but identified a subgroup that could benefit from ramucirumab treatment, the REACH-2 trial was a randomized, placebo-controlled trial, designed to assess ramucirumab as second line in patients with alpha-fetoprotein (AFP) ≥400 ng/mL. The results of REACH-2 were published in February 2019, leading to Food and Drug Administration and European Medicines Agency approval of the drug as second-line agent for advanced HCC (after sorafenib) in patients with AFP ≥400 ng/mL. For the first time in the history of systemic treatments for HCC, a predictive factor of efficacy was identified. In this review, we also discuss the potential clinical development of systemic treatments in HCC, focusing on combination therapies with immunotherapy (following the recent results of the combination of atezolizumab and bevacizumab in the IMbrave 150 clinical trial) and treatment sequences as a way to maximize survival benefit.

Atezolizumab plus Bevacizumab in Unresectable Hepatocellular Carcinoma

BACKGROUND

The combination of atezolizumab and bevacizumab showed encouraging antitumor activity and safety in a phase 1b trial involving patients with unresectable hepatocellular carcinoma.

METHODS

In a global, open-label, phase 3 trial, patients with unresectable hepatocellular carcinoma who had not previously received systemic treatment were randomly assigned in a 2:1 ratio to receive either atezolizumab plus bevacizumab or sorafenib until unacceptable toxic effects occurred or there was a loss of clinical benefit. The coprimary end points were overall survival and progression-free survival in the intention-to-treat population, as assessed at an independent review facility according to Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST 1.1).

RESULTS

The intention-to-treat population included 336 patients in the atezolizumab-bevacizumab group and 165 patients in the sorafenib group. At the time of the primary analysis (August 29, 2019), the hazard ratio for death with atezolizumab-bevacizumab as compared with sorafenib was 0.58 (95% confidence interval [CI], 0.42 to 0.79; P<0.001). Overall survival at 12 months was 67.2% (95% CI, 61.3 to 73.1) with atezolizumab-bevacizumab and 54.6% (95% CI, 45.2 to 64.0) with sorafenib. Median progression-free survival was 6.8 months (95% CI, 5.7 to 8.3) and 4.3 months (95% CI, 4.0 to 5.6) in the respective groups (hazard ratio for disease progression or death, 0.59; 95% CI, 0.47 to 0.76; P<0.001). Grade 3 or 4 adverse events occurred in 56.5% of 329 patients who received at least one dose of atezolizumab-bevacizumab and in 55.1% of 156 patients who received at least one dose of sorafenib. Grade 3 or 4 hypertension occurred in 15.2% of patients in the atezolizumab-bevacizumab group; however, other high-grade toxic effects were infrequent.

CONCLUSIONS

In patients with unresectable hepatocellular carcinoma, atezolizumab combined with bevacizumab resulted in better overall and progression-free survival outcomes than sorafenib. (Funded by F. Hoffmann-La Roche/Genentech; ClinicalTrials.gov number, NCT03434379.).

IMbrave 050: a Phase III trial of atezolizumab plus bevacizumab in high-risk hepatocellular carcinoma after curative resection or ablation

Hepatocellular carcinoma recurs in 70-80% of cases following potentially curative resection or ablation and the immune component of the liver microenvironment plays a key role in recurrence. Many immunosuppressive mechanisms implicated in HCC recurrence are modulated by VEGF and/or immune checkpoints such as PD-L1. Atezolizumab (PD-L1 inhibitor) plus bevacizumab (VEGF inhibitor) has been shown to significantly improve overall survival, progression-free survival and overall response rate in unresectable HCC. Dual PD-L1/VEGF blockade may be effective in reducing HCC recurrence by creating a more immune-favorable microenvironment. We describe the rationale and design of IMbrave 050 (NCT04102098), a randomized, open-label, Phase III study comparing atezolizumab plus bevacizumab versus active surveillance in HCC patients at high-risk of recurrence following curative resection or ablation. The primary end point is recurrence-free survival. Clinical Trial Registration: NCT04102098.

Systemic Therapy for Hepatocellular Carcinoma: Advances and Hopes

The majority of patients with hepatocellular carcinoma (HCC) are diagnosed at an advanced stage that can only benefit from systemic treatments. Although HCC is highly treatmentresistant, significant achievements have been made in the molecular targeted therapy and immunotherapy of HCC. In addition to regorafenib, cabozantinib and ramucirumab were approved for the second- line targeted treatment by the FDA after disease progression on sorafenib. Nivolumab failed to demonstrate remarkable benefit in overall survival (OS) as first-line therapy, while pembrolizumab did not achieve pre-specified statistical significance in both OS and progression-free survival (PFS) as second-line treatment. Combinations of targeted agents, immune checkpoint inhibitors and other interventions showed favorable results. In this review, we summarized the progress of systemic therapy in HCC and discussed the future directions of the treatment of HCC.