Health policy: Me-too drugs with limited benefits - the tale of regorafenib for HCC

FDA-approved small molecule kinase inhibitors for cancer treatment (2001-2015): Medical indication, structural optimization, and binding mode Part I

The dysregulation of kinases has emerged as a major class of targets for anticancer drug discovery given its node roles in the etiology of tumorigenesis, progression, invasion, and metastasis of malignancies, which is validated by the FDA approval of 28 small molecule kinase inhibitor (SMKI) drugs for cancer treatment at the end of 2015. While the preclinical and clinical data of these drugs are widely presented, it is highly essential to give an updated review on the medical indications, design principles and binding modes of these anti-tumor SMKIs approved by the FDA to offer insights for the future development of SMKIs with specific efficacy and safety.

The Social Value Misconception in Clinical Research

Clinical researchers should help respect the autonomy and promote the well-being of prospective study participants by helping them make voluntary, informed decisions about enrollment. However, participants often exhibit poor understanding of important information about clinical research. Bioethicists have given special attention to "misconceptions" about clinical research that can compromise participants' decision-making, most notably the "therapeutic misconception." These misconceptions typically involve false beliefs about a study's purpose, or risks or potential benefits for participants. In this article, we describe a misconception involving false beliefs about a study's potential benefits for non-participants, or its expected social value. This social value misconception can compromise altruistically motivated participants' decision-making, potentially threatening their autonomy and well-being. We show how the social value misconception raises ethical concerns for inherently low-value research, hyped research, and even ordinary research, and advocate for empirical and normative work to help understand and counteract this misconception's potential negative impacts on participants.

Systemic Therapy for Advanced Hepatocellular Carcinoma: ASCO Guideline Update

PURPOSE

To update an evidence-based guideline to assist in clinical decision-making for patients with advanced hepatocellular carcinoma (HCC).

METHODS

ASCO convened an Expert Panel to update the 2020 guideline on systemic therapy for HCC. The panel updated the systematic review to include randomized controlled trials (RCTs) published through October 2023 and updated recommendations.

RESULTS

Ten new RCTs met the inclusion criteria and were added to the evidence base.

RECOMMENDATIONS

Atezolizumab + bevacizumab (atezo + bev) or durvalumab + tremelimumab (durva + treme) may be offered first-line for patients with advanced HCC, Child-Pugh class A liver disease, and Eastern Cooperative Oncology Group performance status 0-1. Where there are contraindications to these therapies, sorafenib, lenvatinib, or durvalumab may be offered first-line. Following first-line treatment with atezo + bev, second-line therapy with a tyrosine kinase inhibitor (TKI), ramucirumab (for patients with alpha-fetoprotein [AFP] ≥400 ng/mL), durva + treme, or nivolumab + ipilimumab (nivo + ipi) may be recommended for appropriate candidates. Following first-line therapy with durva + treme, second-line therapy with a TKI is recommended. Following first-line treatment with sorafenib or lenvatinib, second-line therapy options include cabozantinib, regorafenib for patients who previously tolerated sorafenib, ramucirumab (AFP ≥400 ng/mL), nivo + ipi, or durvalumab; atezo + bev or durva + treme may be considered for patients who did not have access to these therapies in the first-line setting, and do not have contraindications. Pembrolizumab or nivolumab are also options for appropriate patients following sorafenib or lenvatinib. Third-line therapy may be considered in Child-Pugh class A patients with good PS, using one of the agents listed previously that has a nonidentical mechanism of action with previously received therapy. A cautious approach to systemic therapy is recommended for patients with Child-Pugh class B advanced HCC. Further guidance on choosing between options is included within the guideline.Additional information is available at www.asco.org/gastrointestinal-cancer-guidelines.

To Investigate Growth Factor Receptor Targets and Generate Cancer Targeting Inhibitors

Receptor tyrosine kinase (RTK) regulates multiple pathways, including Mitogenactivated protein kinases (MAPKs), PI3/AKT, JAK/STAT pathway, etc. which has a significant role in the progression and metastasis of tumor. As RTK activation regulates numerous essential bodily processes, including cell proliferation and division, RTK dysregulation has been identified in many types of cancers. Targeting RTK is a significant challenge in cancer due to the abnormal upregulation and downregulation of RTK receptors subfamily EGFR, FGFR, PDGFR, VEGFR, and HGFR in the progression of cancer, which is governed by multiple RTK receptor signalling pathways and impacts treatment response and disease progression. In this review, an extensive focus has been carried out on the normal and abnormal signalling pathways of EGFR, FGFR, PDGFR, VEGFR, and HGFR and their association with cancer initiation and progression. These are explored as potential therapeutic cancer targets and therefore, the inhibitors were evaluated alone and merged with additional therapies in clinical trials aimed at combating global cancer.

Small Molecule Kinase Inhibitor Drugs (1995-2021): Medical Indication, Pharmacology, and Synthesis

The central role of dysregulated kinase activity in the etiology of progressive disorders, including cancer, has fostered incremental efforts on drug discovery programs over the past 40 years. As a result, kinase inhibitors are today one of the most important classes of drugs. The FDA approved 73 small molecule kinase inhibitor drugs until September 2021, and additional inhibitors were approved by other regulatory agencies during that time. To complement the published literature on clinical kinase inhibitors, we have prepared a review that recaps this large data set into an accessible format for the medicinal chemistry community. Along with the therapeutic and pharmacological properties of each kinase inhibitor approved across the world until 2020, we provide the synthesis routes originally used during the discovery phase, many of which were only available in patent applications. In the last section, we also provide an update on kinase inhibitor drugs approved in 2021.

Sulfarotene, a synthetic retinoid, overcomes stemness and sorafenib resistance of hepatocellular carcinoma via suppressing SOS2-RAS pathway

BACKGROUND

Recurrent hepatocellular carcinoma (HCC) shows strong resistance to sorafenib, and the tumor-repopulating cells (TRCs) with cancer stem cell-like properties are considered a driver for its high recurrent rate and drug resistance.

METHODS

Suppression of TRCs may thus be an effective therapeutic strategy for treating this fatal disease. We evaluated the pharmacology and mechanism of sulfarotene, a new type of synthetic retinoid, on the cancer stem cell-like properties of HCC TRCs, and assessed its preclinical efficacy in models of HCC patient-derived xenografts (PDXs).

RESULTS

Sulfarotene selectively inhibited the growth of HCC TRCs in vitro and significantly deterred TRC-mediated tumor formation and lung metastasis in vivo without apparent toxicity, with an IC₅₀ superior to that of acyclic retinoid and sorafenib, to which the recurrent HCC exhibits significant resistance at advanced stage. Sulfarotene promoted the expression and activation of RARα, which down-regulated SOS2, a key signal mediator associated with RAS activation and signal transduction involved in multiple downstream pathways. Moreover, sulfarotene selectively inhibited tumorigenesis of HCC PDXs with high expression for SOS2.

CONCLUSIONS

Our study identified sulfarotene as a selective inhibitor for the TRCs of HCC, which targets a novel RARα-SOS2-RAS signal nexus, shedding light on a new, promising strategy of target therapy for advanced liver cancer.

The value of new drugs for advanced prostate cancer

BACKGROUND

The US Food and Drug Administration has recently approved a number of new cancer drugs. The clinical trials that serve as the basis for new cancer drug approvals may not reflect how the drugs will perform in routine practice and do not measure the impact of the drugs on spending. The authors sought to evaluate the real-world effectiveness and value of drugs recently approved for advanced prostate cancer.

METHODS

Using Surveillance, Epidemiology, and End Results-Medicare data, the authors identified fee-for-service Medicare beneficiaries aged 65 years or older who began treatment with a drug approved for metastatic castration-resistant prostate cancer in 2007-2009, when only 1 drug was approved for metastatic castration-resistant prostate cancer, and in 2014-2016, when 5 additional drugs were approved. They calculated life expectancy and lifetime medical costs (ie, Medicare reimbursements) for each group.

RESULTS

Between 2007-2009 and 2014-2016, life expectancy increased by 12.6 months. Lifetime medical costs increased by $87,000. The incremental cost per life-year gained was $83,000.

CONCLUSION

The release of 5 new drugs coincided with increases in survival rates and spending. This study's estimates indicate that the new drugs collectively were cost-effective.

Metabolic pathway analyses identify proline biosynthesis pathway as a promoter of liver tumorigenesis

BACKGROUND & AIM

Under the regulation of various oncogenic pathways, cancer cells undergo adaptive metabolic programming to maintain specific metabolic states that support their uncontrolled proliferation. As it has been difficult to directly and effectively inhibit oncogenic signaling cascades with pharmaceutical compounds, focusing on the downstream metabolic pathways that enable indefinite growth may provide therapeutic opportunities. Thus, we sought to characterize metabolic changes in hepatocellular carcinoma (HCC) development and identify metabolic targets required for tumorigenesis.

METHODS

We compared gene expression profiles of Morris Hepatoma (MH3924a) and DEN (diethylnitrosamine)-induced HCC models to those of liver tissues from normal and rapidly regenerating liver models, and performed gain- and loss-of-function studies of the identified gene targets for their roles in cancer cell proliferation in vitro and in vivo.

RESULTS

The proline biosynthetic enzyme PYCR1 (pyrroline-5-carboxylate reductase 1) was identified as one of the most upregulated genes in the HCC models. Knockdown of PYCR1 potently reduced cell proliferation of multiple HCC cell lines in vitro and tumor growth in vivo. Conversely, overexpression of PYCR1 enhanced the proliferation of the HCC cell lines. Importantly, PYCR1 expression was not elevated in the regenerating liver, and KD or overexpression of PYCR1 had no effect on proliferation of non-cancerous cells. Besides PYCR1, we found that additional proline biosynthetic enzymes, such as ALDH18A1, were upregulated in HCC models and also regulated HCC cell proliferation. Clinical data demonstrated that PYCR1 expression was increased in HCC, correlated with tumor grade, and was an independent predictor of clinical outcome.

CONCLUSION

Enhanced expression of proline biosynthetic enzymes promotes HCC cell proliferation. Inhibition of PYCR1 or ALDH18A1 may be a novel therapeutic strategy to target HCC.

LAY SUMMARY

Even with the recently approved immunotherapies against liver cancer, currently available medications show limited clinical benefits or efficacy in the majority of patients. As such, it remains a top priority to discover new targets for effective liver cancer treatment. Here, we identify a critical role for the proline biosynthetic pathway in liver cancer development, and demonstrate that targeting key proteins in the pathway, namely PYCR1 and ALDH18A1, may be a novel therapeutic strategy for liver cancer.

Systemic Treatment for Advanced Hepatocellular Carcinoma

BACKGROUND

Patients with advanced hepatocellular carcinoma (HCC) have a poor prognosis. First-line sorafenib has been the standard of care for a decade, but the treatment landscape is expanding. This review provides a practical overview of current and future systemic treatment options for advanced HCC and their place in clinical practice.

SUMMARY

First-line sorafenib and lenvatinib have shown to improve the survival of patients with advanced HCC. In the second line, regorafenib provides benefit for patients who previously tolerated sorafenib. Anti-PD1 antibodies, nivolumab and pembrolizumab, recently became available for second-line use in the US. Ramucirumab (for patients with α-fetoprotein [AFP] levels ≥400) and cabozantinib present potential future second-line treatment options. Combinations of systemic and locoregional treatment, such as radiofrequency ablation or selective internal radiotherapy, require further research. Precision medicine has not yet been translated into clinical practice, as the most common driver mutations (TERT promoter, CTNNB1, TP53, and ARID1A mutations) have not yet been shown to be suitable therapeutic targets. However, our growing understanding of signaling pathways and efforts in drug development are expected to pave the way for precision medicine in HCC in the future. Evaluating the place for the current and novel systemic treatment options in clinical practice can be challenging due to the diverse toxicity profiles of the treatment options and characteristics of the patient population. Sorafenib data elucidate the effect patient characteristics (such as the performance score, Child-Pugh class, AFP, etiology of the underlying disease, and level of macrovascular invasion and extrahepatic spread) may have on outcomes in advanced stages.

KEY MESSAGES

Lenvatinib is expected to join sorafenib as a preferred first-line treatment in advanced HCC. In the second line, the treatment of choice, regorafenib, is soon expected to be accompanied by cabozantinib and ramucirumab in patients with AFP ≥400 ng/mL, whereas nivolumab and pembrolizumab present second-line alternatives in the US.

Meta-Analysis of Regorafenib-Associated Adverse Events and Their Management in Colorectal and Gastrointestinal Stromal Cancers

INTRODUCTION

To assess the risk factors associated with regorafenib-related adverse events (AEs) in metastatic colorectal cancer (mCRC) and gastrointestinal stromal tumors (GIST). We also evaluated different measures of combatting AEs and their success rate to aid physicians in early identification and management of reported AEs.

METHODS

A literature search was conducted through the electronic databases PubMed, Embase, and Cochrane Central Register of Controlled Trials up to May 2018 according to the pre-specified inclusion and exclusion criteria. Pooled estimates with Pearson correlation were obtained with fixed or random-effects models.

RESULTS

From our analysis, it was evident that AEs were more common in patients aged less than 65 years compared to those aged at least 65 years (71.3% vs. 27.6%, p = 0.001). A statistically significant correlation was observed between the occurrence of AEs and a dose of 160 mg (r = 0.967; p = 0.001) while no significant correlation was found at 120 mg and 80 mg. The common measures used to manage AEs included lowering the regorafenib dose (41%), intermittent drug withdrawal (66.7%), and complete drug withdrawal (19%). About 57% of patients recovered from AE after their initiating dose was lowered.

CONCLUSION

Regorafenib-associated AEs are more common at an initiating dose of 160 mg. Considering that the efficacy depends on the dosage, 120 mg might be a better choice for mCRC and GIST patients; further studies are needed to validate the results of our analysis. Further prompt identification and management of AEs are required to help the patients continue with drug therapy.

Cost-Effectiveness of Cabozantinib in the Second-Line Treatment of Advanced Hepatocellular Carcinoma

Background: Treatment options are limited for patients with advanced hepatocellular carcinoma (HCC) that progresses after treatment with sorafenib. Cabozantinib, an oral small molecule inhibitor of multiple tyrosine kinase receptors, recently showed improved overall survival (OS) compared with placebo in sorafenib-pretreated patients with advanced HCC in the CELESTIAL trial. This study assessed the cost-effectiveness of cabozantinib for second-line treatment of patients with advanced HCC from a US healthcare system perspective. Patients and Methods: Cost and utility data were extracted from the CELESTIAL trial and used to determine the cost-effectiveness of cabozantinib compared with placebo plus best supportive care. The main outcome of this study was the incremental cost-effectiveness ratio (ICER), expressed as cost per quality-adjusted life year (QALY) gained by using cabozantinib compared with placebo plus best supportive care in sorafenib-pretreated HCC. Results: In the base-case analysis using data from the CELESTIAL trial, the incremental QALY and ICER were 0.067 and $1,040,675 for cabozantinib compared with placebo and best supportive care. OS reported in the CELESTIAL trial (hazard ratio, 0.76; 95% CI, 0.63–0.92) had the strongest association with the ICER. In one-way sensitivity analyses, there were no scenarios in which cabozantinib was cost-effective. In a cost-threshold analysis, cabozantinib would have to be priced at least $50 per pill to be cost-effective considering a willingness to pay of $100,000 per QALY. Although the CELESTIAL trial demonstrated that cabozantinib improves OS compared with placebo in patients with HCC that progresses after treatment with sorafenib, our analysis shows that cabozantinib is not a cost-effective therapy in this scenario. Conclusions: At current costs, cabozantinib is not cost-effective for second-line therapy of HCC in the United States.

Preclinical comparison of regorafenib and sorafenib efficacy for hepatocellular carcinoma using multimodality molecular imaging

Sorafenib has been used as a clinical targeted therapy for hepatocellular carcinoma (HCC) for more than a decade. In 2017, regorafenib was approved for HCC treatment and has since been reported to prolong the survival of advanced HCC patients after treatment failure with sorafenib. However, there has been no direct systematic comparison of the therapeutic effects of regorafenib and sorafenib against HCC. In this study, we comprehensively compared the therapeutic effects of sorafenib and regorafenib against HCC in vitro and in vivo using multimodality molecular imaging, which can show molecular and cellular differences at early stages. The side effects of sorafenib and regorafenib were also systematically evaluated. The data showed that compared with sorafenib treatment, regorafenib exerted stronger antitumor and antiangiogenic effects and significantly increased the survival rate of HCC mice. Sorafenib but not regorafenib treatment caused body weight loss and liver and kidney dysfunction, while regorafenib but not sorafenib treatment caused hypertension. Our study may provide an experimental basis for the guidance of clinical HCC targeted treatment with regorafenib and sorafenib.

Pregnane X receptor mediates sorafenib resistance in advanced hepatocellular carcinoma

BACKGROUND

Kinase inhibitor sorafenib is the most widely used drug for advanced HCC clinical treatment nowadays. However, sorafenib administration is only effective for a small portion of HCC patients, and the majority develop sorafenib-resistance during treatment. Thus, it is urgent to discover the endogenous mechanism and identify new pharmaceutical targets of sorafenib-resistance.

METHODS

Pregnane X receptor (PXR) was detected by immunohistochemistry and quantitative PCR. GST-pull down and LC-MS/MS was used to detect the interaction of PXR and Sorafenib. To test the properties of HCC tumor growth and metastasis, in vivo tumor explant model, FACS, trans-well assay, cell-survival inhibitory assay and Western blot were performed. In terms of mechanistic study, additional assays such as ChIP and luciferase reporter gene assay were applied.

RESULTS

In the present work, we found high PXR level in clinical specimens is related to the poor prognosis of Sorafenib treated patients. By the mechanistic studies, we show that sorafenib binds to PXR and activates PXR pathway, and by which HCC cells develop sorafenib-resistance via activating. Moreover, PXR overexpression helps HCC cells to persist to sorafenib treatment.

CONCLUSION

This study reports the endogenous sorafenib-resistance mechanism in HCC cells, which offers an opportunity to design new therapeutic approaches for HCC treatment.

GENERAL SIGNIFICANCE

PXR mediates sorafenib-resistance in HCC cells and targeting PXR can be a useful approach to facilitate HCC treatment.

Me too-drugs with limited benefits - the tale of regorafenib for HCC

This corrects the article DOI: 10.1038/nrclinonc.2017.100.

Yap promotes hepatocellular carcinoma metastasis and mobilization via governing cofilin/F-actin/lamellipodium axis by regulation of JNK/Bnip3/SERCA/CaMKII pathways

Despite the increasingly important role of Hippo-Yap in hepatocellular carcinoma (HCC) development and progression, little insight is available at the time regarding the specifics interaction of Yap and cancer cells migration. Here, we identified the mechanism by which tumor-intrinsic Yap deletion resulted in HCC migratory inhibition. Yap was greatly upregulated in HCC and its expression promoted the cells migration. Functional studies found that knockdown of Yap induced JNK phosphorylation which closely bound to the Bnip3 promoter and contributed to Bnip3 expression. Higher Bnip3 employed excessive mitophagy leading to mitochondrial dysfunction and ATP shortage. The insufficient ATP inactivated SERCA and consequently triggered intracellular calcium overload. As the consequence of calcium oscillation, Ca/calmodulin-dependent protein kinases II (CaMKII) was signaled and subsequently inhibited cofilin activity via phosphorylated modification. The phosphorylated cofilin failed to manipulate F-actin polymerization and lamellipodium formation, resulting into the impairment of lamellipodium-based migration. Collectively, our results identified Hippo-Yap as the tumor promoter in hepatocellular carcinoma that mediated via activation of cofilin/F-actin/lamellipodium axis by limiting JNK-Bnip3-SERCA-CaMKII pathways, with potential application to HCC therapy involving cancer metastasis.

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Yap is upregulated in the hepatocellular carcinoma and promotes cancer cell migration.

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Loss of Yap impairs cell mobility via inhibiting cofilin/F-actin/lamellipodium by activation of JNK-Bnip3-SERCA-CaMKII.

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Loss of Yap enhances JNK phosphorylation which triggers Bnip3-required mitophagy.

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Excessive mitophagy induces mitochondrial energy disorder which blunts SERCA and causes calcium overload.

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The calcium overload drives CaMKII which inactivates cofilin, leading to F-actin degradation and lamellipodium collapse.