A phase II randomized dose escalation trial of sorafenib in patients with advanced hepatocellular carcinoma

Anticancer Drugs Compared to No Anticancer Drugs in Patients with Advanced Hepatobiliary Cancer: A Mapping Review and Evidence Gap Map

Introduction

Despite being commonly recommended, the impact of anticancer drugs (ACDs) on patient-important outcomes beyond survival for advanced hepatobiliary cancers (HBCs) may not have been sufficiently assessed. We aim to identify and map the evidence regarding ACDs versus best supportive care (BSC) for advanced HBCs, considering patient-centered outcomes.

Methods

In this mapping review, we included systematic reviews, randomized controlled trials, quasi-experimental, and observational studies comparing ACDs (chemotherapy, immunotherapy, biological/targeted therapy) versus BSC for advanced HBCs. We searched MEDLINE (PubMed), EMBASE (Ovid), Cochrane Library, Epistemonikos, PROSPERO and clinicaltrials.gov for eligible studies. Two reviewers performed the screening and data extraction processes. We developed evidence maps for each type of cancer.

Results

We included 87 studies (60 for advanced liver cancer and 27 for gallbladder or bile duct cancers). Most of the evidence favored ACDs for survival outcomes, and BSC for toxicity. We identified several evidence gaps for non-survival outcomes, including quality of life or quality of end-of-life care.

Discussion

Patient-important outcomes beyond survival in advanced HBCs are insufficiently assessed by the available evidence. Future studies need to address these gaps to better inform decision-making processes.

Systemic Oncological Treatments versus Supportive Care for Patients with Advanced Hepatobiliary Cancers: An Overview of Systematic Reviews

BACKGROUND

The trade-off between systemic oncological treatments (SOTs) and UPSC in patients with primary advanced hepatobiliary cancers (HBCs) is not clear in terms of patient-centred outcomes beyond survival. This overview aims to assess the effectiveness of SOTs (chemotherapy, immunotherapy and targeted/biological therapies) versus UPSC in advanced HBCs.

METHODS

We searched for systematic reviews (SRs) in PubMed, EMBASE, the Cochrane Library, Epistemonikos and PROSPERO. Two authors assessed eligibility independently and performed data extraction. We estimated the quality of SRs and the overlap of primary studies, performed de novo meta-analyses and assessed the certainty of evidence for each outcome.

RESULTS

We included 18 SRs, most of which were of low quality and highly overlapped. For advanced hepatocellular carcinoma, SOTs showed better overall survival (HR = 0.62, 95% CI 0.55-0.77, high certainty for first-line therapy; HR = 0.85, 95% CI 0.79-0.92, moderate certainty for second-line therapy) with higher toxicity (RR = 1.18, 95% CI 0.87-1.60, very low certainty for first-line therapy; RR = 1.58, 95% CI 1.28-1.96, low certainty for second-line therapy). Survival was also better for SOTs in advanced gallbladder cancer. No outcomes beyond survival and toxicity could be meta-analysed.

CONCLUSION

SOTs in advanced HBCs tend to improve survival at the expense of greater toxicity. Future research should inform other patient-important outcomes to guide clinical decision making.

Systematic literature review of trials assessing recommended systemic treatments in hepatocellular carcinoma

AIM

To identify and evaluate the similarity of all trials assessing recommended treatments for advanced hepatocellular carcinoma.

MATERIALS & METHODS

Single arm and randomized trials from any phase and published any time up to February 2021 were systematically searched.

RESULTS

From 5677 records reviewed, 50 trials were included in the review, and 24 for assessed for similarity. In the first-line (1L) setting, several trials assessing sorafenib were noted for enrolling patients with more severe disease and/or performance status than other 1L trials; trials within the second-line (2L) setting were generally similar. Median survival was <2 years in all trial arms.

CONCLUSIONS

Trials assessing recommended treatments are largely similar and appropriate for quantitative comparisons of several efficacy and safety outcomes.

Pharmacokinetics and pharmacogenetics of sorafenib in patients with hepatocellular carcinoma: Implications for combination trials

BACKGROUND & AIMS

Sorafenib and lenvatinib are the first-line treatments approved in hepatocellular carcinoma (HCC), but information is lacking about the relationships between their pharmacokinetics, patients pharmacogenetic profiles, adverse events (AE) and overall survival. We aimed to elucidate these relationships of tyrosine Kinase Inhibitors, such as sorafenib, in order to improve the design of trials testing it in combination with checkpoint inhibitors.

METHODS

We assessed the pharmacokinetics of sorafenib and its N-oxide metabolite at day-0, day-7, day-30, day-60, day-90, day-120, day-150 and day-180 and nine single-nucleotide polymorphisms (SNP) in five genes related to sorafenib metabolism/transport to identify the best point for starting the combination between tyrosine kinases and checkpoint inhibitors.

RESULTS

We prospectively included 49 patients (96% cirrhotic, 37% hepatitis-C, 82% Child-Pugh-A and 59% BCLC-C). Pharmacokinetic values peaked at day-7 and progressively declined until day-60. In the 16 patients without further dose modifications after day-60, pharmacokinetic values remained stable through day-180 (sorafenib P = .90; N-oxide P = .93). Pharmacokinetic values were higher in patients with early dermatological adverse events and lower in patients with early diarrhoea. Sorafenib and N-oxide pharmacokinetic values varied linearly with different alleles of MRP2*3972.

CONCLUSIONS

Sorafenib's pharmacokinetics is heterogeneous across HCC patients. This heterogeneity affects adverse events development and must be taken into account in setting the dose and timing of its combination with checkpoint inhibitors.

Management of adverse events with tailored sorafenib dosing prolongs survival of hepatocellular carcinoma patients

BACKGROUND & AIMS

Sorafenib is associated with multiple adverse events (AEs), potentially causing its permanent interruption. It is unknown how physicians' experience has impacted on the management of these AEs and consequently on clinical outcomes. We aimed to assess whether AE management changed over time and if these modifications impacted on treatment duration and overall survival (OS).

METHODS

We analysed the prospectively collected data of 338 consecutive patients who started sorafenib between January 2008 and December 2017 in 3 tertiary care centres in Italy. Patients were divided according to the starting date: Group A (2008-2012; n = 154), and Group B (2013-2017, n = 184). Baseline and follow-up data were compared. In the OS analysis, patients who received second-line treatments were censored when starting the new therapy.

RESULTS

Baseline characteristics, AEs, and radiological response were consistent across groups. Patients in Group B received a lower median daily dose (425 vs. 568 mg/day, p <0.001) due to more frequent dose modifications. However, treatment duration was longer (5.8 vs. 4.1 months, p = 0.021) with a trend toward a higher cumulative dose in Group B. Notably, the OS was also higher (12.0 vs. 11.0 months, p = 0.003) with a sharp increase in the 2-year survival rate (28.1 vs. 18.4%, p = 0.003) in Group B. Multivariate time-dependent Cox regression analysis confirmed later period of treatment (2013-2017) as an independent predictor of survival (HR 0.728; 95%CI 0.581-0.937; p = 0.013). Unconsidered confounders were unlikely to affect these results at the sensitivity analysis.

CONCLUSIONS

Experience in the management of sorafenib-related AEs prolongs treatment duration and survival. This factor should be considered in the design of future randomised clinical trials including a sorafenib treatment arm, as an underestimate of sample size may derive.

LAY SUMMARY

Sorafenib has been the standard frontline systemic treatment for hepatocellular carcinoma for over a decade. Its tolerability is limited by different adverse events, which might lead to its permanent discontinuation in a sizeable proportion of patients. After a careful analysis of potential confounders, we demonstrated that the physicians' experience in managing adverse events related to sorafenib has improved over time, with longer treatment periods and less permanent discontinuation for toxicities. More importantly, these improvements also translated into longer patient survival. Our results have relevant repercussions in clinical practice and in the design of future clinical trials.

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.

Supplementary Sorafenib Therapies for Hepatocellular Carcinoma-A Systematic Review and Meta-Analysis: Supplementary Sorafenib for Liver Cancer

BACKGROUND

Hepatocellular carcinoma (HCC) is the third deadliest cancer worldwide. Sorafenib is considered a supplementary treatment to surgical or locoregional therapies for improving outcomes. We evaluated the efficacy of sorafenib as a supplementary therapy for HCC.

METHODS

We conducted a meta-analysis including 11 randomized controlled trials. Patients with HCC and studies in which sorafenib was administered alone and compared with placebo or those in which sorafenib was administered in combination with another treatment and compared with that treatment alone were included. The overall effects (OEs) on overall survival and time to progression were pooled as hazard ratios.

RESULTS

The OEs of sorafenib as a first-line therapy versus placebo for unresectable HCC were 0.62 [95% confidence interval (CI): 0.50-0.77] and 0.58 (95% CI: 0.47-0.70), respectively. The OEs of sorafenib as a second-line therapy versus placebo for progressive HCC were 0.73 (95% CI: 0.47-1.13) and 0.54 (95% CI: 0.30-0.97), respectively. The OEs of sorafenib as an adjuvant therapy versus placebo for early HCC were 1.00 (95% CI: 0.76-1.30) and 0.89 (95% CI: 0.74-1.08), respectively. The OEs of sorafenib combined with transarterial chemoemboliztion (TACE) versus placebo combined with TACE were 0.80 (95% CI: 0.54-1.21) and 0.85 (95% CI: 0.70-1.04), respectively. The OEs of sorafenib as an adjuvant to TACE versus placebo as an adjuvant to TACE for intermediate HCC were 1.06 (95% CI: 0.69-1.64) and 0.65 (95% CI: 0.31-1.36), respectively.

CONCLUSIONS

Sorafenib was effective as a first-line therapy for unresectable HCC, but it was ineffective as a second-line or adjuvant therapy. Sorafenib did not increase the efficacy of TACE.

Dose-Finding Studies Among Orphan Drugs Approved in the EU: A Retrospective Analysis

In the development process for new drugs, dose‐finding studies are of major importance. Absence of these studies may lead to failed phase 3 trials and delayed marketing authorization. In our study we investigated to what extent dose‐finding studies are performed in the case of orphan drugs for metabolic and oncologic indications. We identified all orphan drugs that were authorized until August 1, 2017. European Public Assessment Reports were used to extract the final dose used in the summary of product characteristics, involvement of healthy volunteers, study type, end points used, number of patients, number of doses, studies in special populations, and dose used for phase 3 studies. Each drug was checked for major objections and dose changes postmarketing. We included 49 orphan drugs, of which 28 were indicated for metabolic disorders and 21 for oncologic indications. Dose‐finding studies were performed in 32 orphan drugs, and studies in healthy volunteers in 26. The absence of dose‐finding studies was mostly due to the rarity of the disease. In this case the dose was determined based on factors such as animal studies or clinical experience. Dose‐related major objections were raised for 9 orphan drugs. Postmarketing dose‐finding studies were conducted in 18 orphan drugs, but dose changes were applied in only 2 drugs. In conclusion, dose‐finding studies in the case of metabolic and oncologic orphan drugs were conducted in the development programs of two thirds of orphan drugs. Dose‐finding studies performed postmarketing suggest that registered doses are not always optimal. It is thus important to perform more robust dose‐finding studies both pre‐ and postmarketing.

Survival of Hepatocellular Carcinoma Patients Treated with Sorafenib beyond Progression

Background/Aim

Sorafenib leads to improved survival in advanced hepatocellular carcinoma (HCC) patients. Continuation of sorafenib beyond progression has been a possible treatment strategy when further approved therapeutic agents are lacking.

Methods

We performed a retrospective analysis of all HCC patients at our institution with documented disease progression under treatment with sorafenib. Overall survival (OS) from start of sorafenib treatment was compared between patients who received sorafenib for > 3 weeks beyond progression (group 1) and those who discontinued sorafenib ≤3 weeks after progression (group 2). Group 1 was further subdivided into those patients who received sorafenib for > 3 months (group 1a) and those who received it for ≤3 months (group 1b).

Results

A total of 71 patients were analyzed. Median OS for all patients was 15.4 months. OS in group 1 (15.6 months) and 2 (13.0 months) was similar (p = 0.90). Patients in group 1a showed significantly prolonged median OS (19.7 months) compared to that of patients in group 1b (13.6 months, p = 0.004), and they showed a trend towards prolonged OS compared to group 2 (p = 0.126). For patients with a poor prognosis according to their Child-Pugh stage, performance status, alpha-fetoprotein, and response to prior sorafenib treatment, OS was significantly prolonged in group 1 versus group 2 (12.1 vs. 6.4 months, p = 0.019).

Conclusion

In HCC patients, continuing sorafenib beyond progression for > 3 months is associated with improved survival compared to discontinuing sorafenib within 3 months. Furthermore, patients with a poor prognosis who continue sorafenib beyond progression in general show significantly prolonged survival.

The earlier, the better: the effects of different administration timepoints of sorafenib in suppressing the carcinogenesis of VEGF in rats

PURPOSE

To investigate the optimal starting time point of sorafenib therapy in suppressing the tumor-promoting effects of VEGF up-regulation, which is frequently found after local therapy in clinical practice.

METHODS

VEGF was intravenously injected to imitate the evaluated expression after local tumor therapy, such as TACE. A total of 40 SD rats bearing hepatic tumors were randomly divided into four groups and sorafenib was administered at different timepoints: (A) control group: VEGF injection only; (B) initiating sorafenib 72 h prior to VEGF injection; (C) initiating sorafenib simultaneously with VEGF injection; (D) initiating sorafenib 72 h post-VEGF injection. The rate of tumor growth, median survival time, expression of VEGF, and microvessel density (MVD), as determined by immunohistochemical (IHC) examination, were compared.

RESULTS

The results revealed that the tumor size and median survival time were significantly different between the three sorafenib groups compared to the control group (p < 0.05). Median survival times were 19.6 ± 1.78, 31.2 ± 6.99, 27.4 ± 4.9, and 26.5 ± 4.6 days in group A, B, C, and D, respectively. Furthermore, there was a difference in statistical significance between the two sorafenib groups B and D (p = 0.04). Tumors were collected for HE staining and IHC examination. The expression levels of VEGF in B, C, and D were 42.8 ± 7.96, 71.9 ± 15.73, and 73.6 ± 13.73, and all of them were significantly lower than that in the control group (88.3 ± 13.61). Furthermore, the level of MVD was 109.2 ± 8.98 in the control group, which was significantly higher than in the three sorafenib groups (45.7 ± 16.92, 77.1 ± 16.29, and 93.6 ± 12.87, all p < 0.05).

CONCLUSIONS

According to our results, the most suitable regimen for the administration of sorafenib is before the increased expression of VEGF, which showed a potential advantage for controlling the tumor growth and prolonging the survival time of test animal via inhibiting VEGF-receptor expression through the bifunction of VEGF, and the reduction of tumor angiogenesis.

Resminostat plus sorafenib as second-line therapy of advanced hepatocellular carcinoma - The SHELTER study

BACKGROUND & AIMS

No established therapies for patients with hepatocellular carcinoma (HCC) and progression on first-line sorafenib treatment currently exist. This phase I/II trial investigated safety, pharmacokinetics and potential biomarkers of the histone deacetylase inhibitor resminostat and a combination therapy with resminostat and sorafenib.

METHODS

Patients with HCC and radiologically confirmed progression on sorafenib were treated in an exploratory, multi-center, open-label, uncontrolled, non-randomized, parallel group phase I/II study. In the combination group (n=38) four dose levels ranged from daily 200 to 600mg resminostat plus 400 to 800mg sorafenib. The monotherapy group (n=19) received 600mg resminostat.

RESULTS

57 patients received treatment. Most common adverse events were gastrointestinal disorders, thrombocytopenia and fatigue. Median maximal histone deacetylase inhibition and highest increase in H4-acetylation matched Tmax of resminostat. Sorafenib or the Child-Pugh score did not affect typical pharmacokinetics characteristics of resminostat. Efficacy assessment as progression-free survival-rate after 6 treatment cycles (12weeks, primary endpoint) was 12.5% for resminostat and 62.5% for resminostat plus sorafenib. Median time to progression and overall survival were 1.8 and 4.1months for resminostat and 6.5 and 8.0months for the combination, respectively. Zinc finger protein 64 (ZFP64) baseline expression in blood cells was found to correlate with overall survival.

CONCLUSIONS

The combination of sorafenib and resminostat in HCC patients was safe and showed early signs of efficacy. Sorafenib did not alter the pharmacokinetic profile of resminostat or its histone deacetylase inhibitory activity in vivo. A prognostic and potentially predictive role of ZFP64 for treatment with resminostat should be further investigated in HCC and possibly other cancer indications.

LAY SUMMARY

No established therapy for patients with advanced hepatocellular carcinoma and progression under first-line systemic treatment with sorafenib currently exists. Epigenetic modulation by inhibition of histone deacetylases might be able to overcome therapy resistance. This exploratory phase I/II clinical study in patients with radiologically confirmed progression under first-line treatment with sorafenib investigated the histone deacetylases inhibitor resminostat as single agent or in combination with continued application of sorafenib.

CLINICAL TRIAL REGISTRATION

The clinical trial has been registered at www.clinicaltrials.gov as NCT00943449.

Meta-analysis of cardiovascular toxicity risks in cancer patients on selected targeted agents

PURPOSE

The purpose was to estimate the risk and severity of cardiovascular toxicities associated with selected targeted agents.

METHODS

We searched English-language literature for randomized clinical trials published between January 1, 2000 and November 30, 2013 of targeted cancer therapy drugs approved by the FDA by November 2010. One hundred ten studies were eligible. Using meta-analytic methods, we calculated the relative risks of several cardiovascular toxicities [congestive heart failure (CHF), decreased left ventricular ejection fraction (DLVEF), myocardial infarction (MI), arrhythmia, and hypertension (HTN)], adjusting for sample size using the inverse-variance technique. For each targeted agent and side effect, we calculated the number needed to harm.

RESULTS

Regarding CHF, trastuzumab showed significantly greater risk of all-grade and high-grade CHF. There was significant increased risk of all-grade DLVEF with sorafenib, sunitinib, and trastuzumab and high-grade DLVEF with bevacizumab and trastuzumab. Sorafenib was associated with significant increased all-grade risk of MI based on one study. None was associated with high-grade risk of MI or increased risk of arrhythmia. Bevacizumab, sorafenib, and sunitinib had significant increased risk of all-grade and high-grade HTN.

CONCLUSIONS

Several of the targeted agents were significantly associated with increased risk of specific cardiovascular toxicities, CHF, DLVEF, and HTN. Several had significant increased risk for high-grade cardiovascular toxicities (CHF, DLVEF, and HTN). Patients receiving such therapy should be closely monitored for these toxicities and early and aggressive treatment should occur. However, clinical experience has demonstrated that some of these toxicities may be reversible and due to secondary effects.

Sorafenib: 10 years after the first pivotal trial

Sorafenib is an oral multikinase inhibitor with anticancer activity against a wide spectrum of cancers. It is currently approved for the treatment of patients with hepatocellular carcinoma, advanced renal cell carcinoma or progressive, locally advanced or metastatic differentiated thyroid carcinoma. In this review, we present a number of studies that investigated the efficacy and safety of sorafenib in these settings. We also discuss the perspectives on the use of this molecule, including the role of sorafenib as comparator for the development of new drugs, the combination of sorafenib with additional therapies (such as transarterial chemoembolization for hepatocellular carcinoma) and the use of this treatment in several other advanced refractory solid tumors.

The Efficacy of Continued Sorafenib Treatment after Radiologic Confirmation of Progressive Disease in Patients with Advanced Hepatocellular Carcinoma

BACKGROUND

Whether radiologically detected progressive disease (PD) is an accurate metric for discontinuing sorafenib treatment in patients with hepatocellular carcinoma (HCC) is unclear. We investigated the efficacy of sorafenib treatment after radiologic confirmation of PD in patients with advanced HCC.

METHODS

We retrospectively analyzed HCC patients treated with sorafenib at Kyushu Medical Center. Six of the 92 patients with radiologically confirmed PD were excluded because they were classified as Child-Pugh C or had an Eastern Cooperative Oncology Group (ECOG) performance status (PS) ≥3; 86 patients were ultimately enrolled.

RESULTS

Among the 86 patients, 47 continued sorafenib treatment after radiologic confirmation of PD (the continuous group), whereas 39 did not (the discontinuous group). The median survival time (MST) in the continuous group after confirmation was 12.9 months compared with 4.5 months in the discontinuous group (p <0.01). The time to progression in the continuous group after confirmation was 2.6 months compared with 1.4 months in the discontinuous group (p <0.01); it was 4.2 months and 2.1 months in patients who had received sorafenib ≥4 months and <4 months, respectively, before confirmation (p = 0.03). In these subgroups, the post-PD MST was 16.7 months and 9.6 months, respectively (p < 0.01). Independent predictors of overall survival after radiologic detection of PD were (hazard ratio, confidence interval): ECOG PS <2 (0.290, 0.107-0.880), Barcelona Clinical Liver Cancer stage B (0.146, 0.047-0.457), serum α-fetoprotein level ≥400 ng/mL (2.801, 1.355-5.691), and post-PD sorafenib administration (0.279, 0.150-0.510).

CONCLUSION

Continuing sorafenib treatment after radiologic confirmation of PD increased survival in patients with advanced HCC. Therefore, radiologically detected PD is not a metric for discontinuation of sorafenib treatment in such patients.

Impact of more detailed categorization of shrinkage or progression ratio at initial imaging response after sorafenib treatment in advanced hepatocellular carcinoma patients

Background

Sorafenib therapy improves survival in unresectable hepatocellular carcinoma (HCC) patients without an objective response. The present study investigated whether the initial imaging response might be a prognostic indicator after administration of sorafenib therapy in HCC patients.

Patients and methods

This retrospective study reviewed unresectable HCC patients undergoing sorafenib therapy. Patients evaluated without complete response, partial response (PR), or progressive disease (PD) at the initial imaging response evaluation by modified Response Evaluation Criteria in Solid Tumors were divided into three groups according to more detailed categorization of the shrinkage/progression ratio in initial imaging response. A comparison of progression-free and overall survival among these groups was performed.

Results

Of the 43 non-PR non-PD patients with target lesions, ten (23.3%) exhibited mild response (MR; −30% to −5%), 14 (32.6%) exhibited no change (NC; −5% to +5%), and 19 (44.2%) exhibited mild-PD (MPD; +5% to +20%). There was no statistical difference in progression-free or overall survival between MR and NC patients. The median progression-free survivals in NC+MR and mild-PD patients were 15.0 and 5.3 months, respectively (P<0.01), and the median survival times were 31.9 and 17.1 months, respectively (P<0.001). In multivariate analysis, etiology (hepatitis C virus) and initial imaging response (MR+NC) was identified as an independently good prognostic factor.

Conclusion

More detailed categorization of shrinkage or progression at the initial imaging response evaluation may be a useful marker for predicting sorafenib treatment outcomes in HCC patients. If the initial imaging response is not progression but stability, sorafenib may have a survival benefit.

Expression of pERK and VEGFR-2 in advanced hepatocellular carcinoma and resistance to sorafenib treatment

BACKGROUND & AIMS

The study aimed to evaluate the tissue expression of molecules involved in intracellular signalling pathways as predictors of response to sorafenib in advanced hepatocellular carcinoma (HCC).

METHODS

We considered 77 patients enrolled into three prospective trials of sorafenib treatment for whom pretreatment tumour tissue was available. The tissue expression of β-catenin, glutamine synthetase (GS), phosphorylated extracellular signal regulated kinase (pERK), phosphorylated v-akt murine thymoma viral oncogene homolog (pAKT) and vascular endothelial growth factor receptor-2 (VEGFR-2) was analysed by immunostaining. Stains were scored semiquantitatively and compared with a reference group of 56 untreated HCCs.

RESULTS

Overall, the expression of antigens was comparable between treated and untreated patients. Shorter progression-free survival (PFS) and overall survival (OS) were associated with increased pERK staining (≥ 2+ scores) (PFS: 75th percentile 4.4 vs 8.4 months; P = 0.01; OS: 75th percentile 7.0 vs 15.0 months; P = 0.005) and VEGFR-2 staining (≥ 2+ scores) (PFS: 75th percentile 3.8 vs 7.0 months; P = 0.039; OS: 75th percentile 6.3 vs 15.0 months; P = 0.004). At multivariate analysis, both pERK and VEGFR-2 staining maintained an independent effect on OS (HR 2.09; 95% CI, 1.13-3.86, P = 0.019 and HR 2.28; 95% CI, 1.13-4.61, P = 0.021 respectively). No effect was observed for the other tested biomarkers.

CONCLUSIONS

Elevated tissue expression of pERK and VEGFR-2 was predictive of poor outcome in advanced HCC treated with sorafenib.

Molecular targeted therapy in hepatocellular carcinoma: from biology to clinical practice and future

OPINION STATEMENT

Hepatocellular carcinoma (HCC) is one of the most lethal cancers globally, particularly in certain regions of the world. Although the major risk factors for HCC have been identified, the specific mechanisms driving hepatocarcinogenesis remain unclear. Sorafenib is the only systemic therapy that has demonstrated an overall survival benefit in patients with advanced HCC and does so primarily through antiangiogenic activity. However, that actual benefit is still relatively small. Extensive research has focused on targeting dysfunctional molecular pathways in HCC. Despite promising preclinical and early-phase studies, other agents have failed to expand upon the efficacy of sorafenib in large-scale randomized trials. As the development of treatment options in the post-sorafenib setting is ongoing, more efforts are being focused on (1) evaluation of molecular agents targeting pathogenic, HCC-specific pathways; (2) the combination of targeted and cytotoxic therapies in selected subgroups; and (3) the combination of systemic and locoregional therapies in various settings. This article provides a review of recently completed and ongoing studies of molecular targeted agents in HCC, including a brief description of the biologic rationale behind these agents.

Factors Associated with Post-Progression Survival in Patients with Advanced Hepatocellular Carcinoma Treated with Sorafenib

Sorafenib exerts modest antitumor activity in patients with advanced hepatocellular carcinoma (HCC), and radiological progressive disease (rPD) does not always correspond to so-called clinical progressive disease (cPD). We evaluated 101 patients who initiated sorafenib treatment for HCC and assessed post-progression survival (PPS) using the Cox proportional hazards model. PPS was calculated from the date of the first rPD until the date of death or the last follow-up. Using Cox model analysis of the 76 patients who experienced first rPD, we identified the Child-Pugh class, Eastern Cooperative Oncology Group performance status, the best antitumor response during treatment (using Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1) and α-fetoprotein levels as independent factors affecting PPS. When these factors were used to define scores ranging from zero to five with a cutoff value of two, PPS of patients who received best supportive care (BSC) after rPD was not statistically significantly different from that of patients who received post-rPD therapy with scores ≥2 (p = 0.220). In contrast, the PPS for the post-rPD therapy group was significantly longer compared with the BSC patients with scores <2 (p < 0.001). Patients who scored ≥2 at their first rPD were judged cPD and as candidates for BSC.

Effects of Sorafenib Dose on Acquired Reversible Resistance and Toxicity in Hepatocellular Carcinoma

Acquired evasive resistance is a major limitation of hepatocellular carcinoma (HCC) treatment with the tyrosine kinase inhibitor (TKI) sorafenib. Recent findings suggest that resistance to sorafenib may have a reversible phenotype. In addition, loss of responsiveness has been proposed to be due to a gradual decrease in sorafenib plasma levels in patients. Here, the possible mechanisms underlying reversible sorafenib resistance were investigated using a Hep3B-hCG orthotopic human xenograft model of locally advanced HCC. Tissue and plasma sorafenib and metabolite levels, downstream antitumor targets, and toxicity were assessed during standard and dose-escalated sorafenib treatment. Drug levels were found to decline significantly over time in mice treated with 30 mg/kg sorafenib, coinciding with the onset of resistance but a greater magnitude of change was observed in tissues compared with plasma. Skin rash also correlated with drug levels and tended to decrease in severity over time. Drug level changes appeared to be partially tumor dependent involving induction of tumoral CYP3A4 metabolism, with host pretreatment alone unable to generate resistance. Escalation from 30 to 60 mg/kg sorafenib improved antitumor efficacy but worsened survival due to excessive body weight loss. Microvessel density was inhibited by sorafenib treatment but remained suppressed over time and dose increase. In conclusion, tumor CYP3A4 induction by sorafenib is a novel mechanism to account for variability in systemic drug levels; however, declining systemic sorafenib levels may only be a minor resistance mechanism. Escalating the dose may be an effective treatment strategy, provided toxicity can be controlled.

Refining sorafenib therapy: lessons from clinical practice

Understanding the best use of sorafenib is essential in order to maximize clinical benefit in hepatocellular carcinoma. Based on Phase III and noninterventional study data, as well as our extensive experience, we discuss dose modification in order to manage adverse events, disease response evaluation and how to maximize treatment benefit. Sorafenib should be initiated at the approved dose (400 mg twice daily) and reduced/interrupted as appropriate in order to manage adverse events. Dose modification should be considered before discontinuation. Appropriate tumor response assessment is critical. Focusing on radiologic response may result in premature sorafenib discontinuation; symptomatic progression should also be considered. If second-line therapies or trials are unavailable, continuing sorafenib beyond radiologic progression may provide a clinical benefit. Our recommendations enable the maximization of treatment duration, and hence clinical benefit, for patients.

Sorafenib in advanced hepatocellular carcinoma: current status and future perspectives

The approval of sorafenib, a multikinase inhibitor targeting primarily Raf kinase and the vascular endothelial growth factor receptor, in 2007 for treating advanced hepatocellular carcinoma (HCC) has generated considerable enthusiasm in drug development for this difficult-to-treat disease. However, because several randomized Phase III studies testing new multikinase inhibitors failed, sorafenib remains the standard of first-line systemic therapy for patients with advanced HCC. Field practice studies worldwide have suggested that in daily practice, physicians are adopting either a preemptive dose modification or a ramp-up strategy to improve the compliance of their patients. In addition, accumulating data have suggested that patients with Child-Pugh class B liver function can tolerate sorafenib as well as patients with Child-Pugh class A liver function, although the actual benefit of sorafenib in patients with Child-Pugh class B liver function has yet to be confirmed. Whether sorafenib can be used as an adjunctive therapy to improve the outcomes of intermediate-stage HCC patients treated with transcatheter arterial chemoembolization or early-stage HCC patients after curative therapies is being investigated in several ongoing randomized Phase III studies. An increasing number of studies have reported that sorafenib exerts "off-target" effects, including the modulation of signaling pathways other than Raf/MEK/ERK pathway, nonapoptotic cell death mechanisms, and even immune modulation. Finally, although sorafenib in combination with chemotherapy or other targeted therapies has the potential to improve therapeutic efficacy in treating HCC, it also increases toxicity. Additional clinical studies are warranted to determine useful sorafenib-based combinations for the treatment of advanced HCC.

Drug therapy for advanced-stage liver cancer

Liver cancer was traditionally treated by surgery or interventional ablative treatments, or, if these options were not feasible, by best supportive care. Since 2008, systemic therapy with the multikinase inhibitor sorafenib has become available worldwide and has become the standard of care for unresectable/non-ablatable or advanced-stage hepatocellular carcinoma (HCC). Sorafenib is able to improve the median overall survival by approximately 3 months. Despite this significant advance in the non-surgical/non-interventional management of liver cancer, this improvement in overall survival is only a first step toward more potent, more targeted, and better tolerated oral antitumor treatments. Since the introduction of sorafenib into clinical practice, several attempts have been made to develop even more effective first-line treatments as well as an effective second-line treatment for HCC. None of these endeavors has been successful so far. The development of drug treatments for HCC has been particularly hampered by the unfortunate push to establish the diagnosis of liver cancer by non-invasive imaging alone, without requiring a liver biopsy for histologic confirmation: this precluded the very necessary search for informative biomarkers and the search for molecular targets for drug development in HCC. This important drawback is being increasingly recognized and corrected. Despite several obstacles remaining to be overcome, it seems reasonable to assume that using a rational, data-driven approach, we will be able to develop better drug treatments for liver cancer in the coming years.

Sorafenib for the treatment of hepatocellular carcinoma

The multikinase inhibitor sorafenib, which inhibits targets related to tumor cell proliferation and angiogenesis, was the first systemic agent to demonstrate a significant improvement in the overall survival for patients with advanced hepatocellular carcinoma (HCC) in two large randomized controlled Phase III trials. Together with its manageable safety profile (mainly diarrhea, hand-foot skin reaction and fatigue), sorafenib was approved for the treatment of patients with (unresectable) HCC in 2007. Since then, sorafenib has been established as the standard of care in Child-Pugh A patients with advanced HCC or in those ineligible for or after failure of locoregional therapies in the intermediate stage of the disease. This article summarizes current knowledge and future perspectives regarding the use of sorafenib in patients with HCC.

Critical role of sorafenib exposure over time for its antitumor activity in thyroid cancer

Sorafenib, a multi-kinase inhibitor that targets the VEGF, PDGF and BRAF pathways, has demonstrated significant clinical activity in metastatic differentiated thyroid cancer. However, all patients eventually experience disease progression with a median progression-free survival close to 10 months. Since sorafenib exposure is known to decrease over time, we hypothesized that dose adjustments aiming to restore adequate exposure could lead to further clinical activity. We report, as a proof of concept on a patient with radio-iodine resistant metastatic thyroid cancer, who experienced disease progression after an initial response to sorafenib (400 mg twice daily). Whereas the thyroglobulin-progression-free survival at standard doses was 6 months, iterative dose optimization led to a prolonged progression-free survival up to 41 months. Sorafenib doses were increased up to 1600 mg bid, in order to maintain clinical activity, and to restore active plasma concentration, since sorafenib exposure had decreased over the time. Toxicity was mild and manageable for more than 2 years. However, the patient eventually experienced grade 3 proteinuria leading to treatment discontinuation. This observation opens up new horizons for daily management of radioactive iodine-refractory differentiated thyroid cancer patients progressing under standard doses of sorafenib, and stress the need to monitor its plasma concentration.

Antiangiogenic treatment in hepatocellular carcinoma: the balance of efficacy and safety

Hepatocellular carcinoma (HCC) is a severe complication of advanced liver disease with a worldwide incidence of more than 600,000 patients per year. Liver function, clinical performance status, and tumor size are considered in the Barcelona Clinic Liver Cancer (BCLC) system. While curative treatment options are available for early stages, most patients present with intermediate- or advanced-stage HCC, burdened with a poor prognosis, substantially influenced by the degree of liver-function impairment. Hypervascularization is a major characteristic of HCC, and antiangiogenic treatments are the basis of treatment in noncurative stages, including interventional and pharmacological treatments. Currently, the tyrosine-kinase inhibitor sorafenib is still the only approved drug for HCC. Further improvements in survival in patients with intermediate- and advanced-stage HCC may be anticipated by both multimodal approaches, such as combination of interventional and systemic treatments, and new systemic treatment options. Until now, the Phase III development of other tyrosine-kinase inhibitors in patients with advanced HCC has failed due to minor efficacy and/or increased toxicity compared to sorafenib. However, promising Phase II data have been reported with MET inhibitors in this hard-to-treat population. This review gives a critical overview of antiangiogenic drugs and strategies in intermediate- and advanced-stage HCC, with a special focus on safety.

Molecular mechanisms underlying the development of hepatocellular carcinoma and molecular targeted therapy

Hepatocellular carcinoma is one of the most common malignant tumors worldwide and remains one of leading causes of death from cancer in China. Hepatocarcinogenesis is a complex process associated with many environmental risk factors, including cellular and molecular signaling pathways, oncogenes and tumor suppressor genes, and the differentiation of cancer stem cells. Molecular targeted therapy is a new approach to the treatment of liver cancer. The main mechanism of therapy is a type of medication that blocks the growth of cancer cells by interfering with specific targeted molecules needed for carcinogenesis and tumor growth, which can enhance the specificity and selectivity of the treatment. In this review, we discuss recent advances in the understanding of molecular mechanisms underlying the development of HCC and in the development of novel cancer therapeutics.