Sorafenib: delivering a targeted drug to the right targets

Approved for the treatment of advanced renal cell carcinoma by the US FDA and other regulatory agencies, sorafenib is an agent with multiple targets that may also prove beneficial in other malignancies. Phase III trials are underway in melanoma, hepatocellular carcinoma and non-small-cell lung cancer. Scrutiny of the Phase II data and correlative studies conducted in that context suggests that inhibition of angiogenesis and signaling in tumor cells may play a part in the clinical efficacy of sorafenib. Although the vascular endothelial growth factor receptor inhibitors are the most populated class of targeted agents in cancer clinical trials, sorafenib may prove to have unique properties that distinguish it. A detailed discussion of the clinical trials in renal cell carcinoma, melanoma and hepatocellular carcinoma highlights what is known and what has yet to be understood about this agent.     

Selected combination therapy with sorafenib: a review of clinical data and perspectives in advanced solid tumors

The development of targeted therapies has provided new options for the management of patients with advanced solid tumors. There has been particular interest in agents that target the mitogen-activated protein kinase pathway, which controls tumor growth and survival and promotes angiogenesis. Sorafenib is an oral multikinase inhibitor that has been proven effective as a single-agent therapy in renal cell carcinoma, and there is a strong rationale for investigating its use in combination with other agents. In particular, targeting multiple Raf isoforms with sorafenib may help to overcome resistance to other agents, while the ability of sorafenib to induce apoptosis may increase the cytotoxicity of chemotherapeutic agents. Based on positive results in preclinical studies, further investigation in phase I and II studies has shown potential antitumor activity when sorafenib is combined with cytotoxic agents in different solid tumors, including hepatocellular carcinoma and melanoma. Promising results have been reported in phase I and II studies of sorafenib combined with paclitaxel and carboplatin, with oxaliplatin in gastric and colorectal cancer, with docetaxel in breast cancer, with gemcitabine in ovarian cancer, and with capecitabine in different solid tumors. Phase II and III studies are currently investigating the use of sorafenib in combination with different agents in a variety of solid tumors. The primary objective of this review is to summarize the early clinical studies of sorafenib with cytotoxic agents and discuss future perspectives of these combinations in different tumor types.     

Nivolumab for the treatment of hepatocellular carcinoma

Introduction: T-cell checkpoint inhibition as a cancer treatment approach has been the main breakthrough in cancer treatment during the last years. Since the approval of the first commercial CTLA-4 antibody ipilimumab in 2011 for the treatment of melanoma, research and drug development in this field has accelerated massively. In 2014, the US Food and Drug Administration (FDA) approved the first PD-1 targeting agent, namely pembrolizumab, shortly followed by nivolumab.

Areas covered: Nivolumab is a fully human immunoglobulin G4 anti-PD-1 monoclonal antibody which is approved for multiple advanced malignancies, including melanoma, non-small cell lung cancer, renal cell cancer, Hodgkin’s lymphoma, squamous head and neck cancer, and urothelial carcinoma. In September 2017, nivolumab was approved by the FDA for liver cancer as a second line treatment after failure of sorafenib based on the data of the multi-cohort phase 1/2 trial CheckMate-040. This article reviews the concept of immunotherapy in liver cancer with focus on nivolumab.

Expert commentary: Immunotherapy in hepatocellular carcinoma is safe and is a new treatment option for patients with advanced stage disease besides sorafenib and regorafenib in the US. Randomized phase III trials of nivolumab, pembrolizumab, atezolizumab, durvalumab and tislelizumab as mono- or combination-therapy are ongoing.     

Metastatic melanoma: scientific rationale for sorafenib treatment and clinical results

In advanced metastatic melanoma (AJCC stage IV), the prognosis is still poor, and views differ on the appropriate systemic treatment for these patients. Therefore, new approaches in therapeutic regimens are mandatory. Sorafenib is an oral multikinase inhibitor that targets 2 classes of kinases which are known to be involved in both tumor proliferation and angiogenesis. These kinases include Raf kinases and the vascular endothelial growth factor (VEGF) receptor. Sorafenib has been evaluated as a single therapy agent as well as in combination with various chemotherapeutical drugs in a number of clinical trials. The vast majority of clinical data exists for patients with advanced renal cell cancer for which sorafenib has been approved by the FDA and EMEA. Very recently, sorafenib was approved for advanced hepatocellular cancers due to its overall survival improvement. Since B-raf gene mutations have been found in 69% of melanoma cell lines, sorafenib was brought into various phase I/II and phase III trials in metastatic melanoma. However, as a single-agent therapy, sorafenib seems to be of limited use. Also, the combination of sorafenib with the chemotherapeutic agents carboplatin and paclitaxel has failed to show superiority in progression-free and overall survival compared to the same chemoregimen plus an oral placebo in a phase III trial (PRISM study). More promising data were observed in large-sized phase II studies on dacarbazine (DTIC) plus sorafenib and temozolomide plus sorafenib. However, these data need to be confirmed in prospective randomized phase III trials. Till then, sorafenib remains an interesting but still experimental new agent for melanoma.     

Safety and tolerability of sorafenib in clear-cell renal cell carcinoma: a Phase III overview

This review summarizes the safety of sorafenib, an oral multikinase inhibitor, focusing on the randomized, placebo-controlled, Phase III Treatment Approaches in Renal Cancer Global Evaluation Trial (TARGET) in renal cell carcinoma, which formed the basis of the approval of sorafenib. Similar to other targeted agents, sorafenib acts primarily to induce disease stabilization, rather than tumor regression, suggesting that long-term administration is necessary. The tolerability of an agent is important in long-term treatment, and a predictable and manageable side-effect profile is advantageous. Although IL-2 and interferon have been standard care treatments for advanced renal cell carcinoma for over a decade, they are poorly tolerated. Targeted agents offer an alternative for patients with advanced renal cell carcinoma, as initial therapy or after failure of cytokine treatment.     

Sorafenib: recent update on activity as a single agent and in combination with interferon-alpha2 in patients with advanced-stage renal cell carcinoma

Metastatic renal cell carcinoma does not respond favorably to conventional treatment strategies and is not very responsive to cytokine therapy. Therefore, novel targeted treatment approaches have been explored for patients with renal cancer who have chemotherapy-refractory disease. Sorafenib (BAY 43-9006) is a smallmolecule inhibitor that has been shown to target members of multiple classes of tyrosine kinases that are known to be involved in tumor cell proliferation and tumor angiogenesis. These kinases include vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2, VEGFR-3, platelet-derived growth factor receptor, Flt-3, c-kit, and Raf kinases. Based on the significant improvement in progressionfree survival, sorafenib received Food and Drug Administration approval in December 2005 for the treatment of renal cell carcinoma. In combination studies, sorafenib with other antitumor agents has demonstrated significant clinical activity in patients with renal cell carcinoma. As discussed in this mini-review, the clinical potency of sorafenib as a single agent or in combination with other antitumor agents is being evaluated in several ongoing clinical trials in patients with renal carcinoma.     

Sorafenib: Recent Update on Activity as a Single Agent and in Combination with Interferon-α2 in Patients with Advanced-Stage Renal Cell Carcinoma

Metastatic renal cell carcinoma does not respond favorably to conventional treatment strategies and is not very responsive to cytokine therapy. Therefore, novel targeted treatment approaches have been explored for patients with renal cancer who have chemotherapy-refractory disease. Sorafenib (BAY 43-9006) is a smallmolecule inhibitor that has been shown to target members of multiple classes of tyrosine kinases that are known to be involved in tumor cell proliferation and tumor angiogenesis. These kinases include vascular endothelial growth factor receptor (VEGFR)–1, VEGFR-2, VEGFR-3, platelet-derived growth factor receptor, Flt-3, c-kit, and Raf kinases. Based on the significant improvement in progressionfree survival, sorafenib received Food and Drug Administration approval in December 2005 for the treatment of renal cell carcinoma. In combination studies, sorafenib with other antitumor agents has demonstrated significant clinical activity in patients with renal cell carcinoma. As discussed in this mini-review, the clinical potency of sorafenib as a single agent or in combination with other antitumor agents is being evaluated in several ongoing clinical trials in patients with renal carcinoma.     

Current status of molecularly targeted therapy for hepatocellular carcinoma: clinical practice

In recent years, molecular-targeted agents have been used clinically to treat various malignant tumors. In May 2009, sorafenib (Nexavar^®) was approved in Japan for “unresectable hepatocellular carcinoma (HCC)”, and was the first molecular-targeted agent for use in liver cancer. To date, sorafenib is the only molecular-targeted agent whose survival benefit has been demonstrated in two global phase III randomized controlled trials, and it has now been approved worldwide. Phase III clinical trials are now underway to compare other molecular-targeted agents with sorafenib as first-line treatment agents, and to evaluate other multi-kinase inhibitors of the vascular endothelial growth factor and platelet-derived growth factor receptors, as well as drugs targeting the epidermal growth factor receptor, insulin-like growth factor receptor, and mammalian target of rapamycin, in addition to other molecules targeting other components of the signal transduction pathways. This review outlines the main pathways involved in the development and progression of HCC and the agents that target these pathways.     

Impressive efficacy of sorafenib in a patient with an hepatocellular carcinoma and a portal vein thrombosis associated with a metastatic ENT cancer

Sorafenib, a new antiangiogenic and antiproliferative agent, is currently used for hepatocellular and renal cell carcinoma. We report here the case of a patient with two cancers, a locally advanced cancer of the piriform sinus and a hepatocellular carcinoma, who was given sorafenib. Tumor response of both cancers might suggest that sorafenib could be effective against head and neck cancer.     

肿瘤靶向治疗新探:多靶点Raf激酶抑制剂

随着对肿瘤分子机制的加深理解，对肿瘤分子靶向治疗的研究已获重大进展。蛋白激酶抑制剂是新近研发的靶向治疗药物之一，通过阻碍细胞内分子传导通路，影响肿瘤细胞的存活、增殖以及疾病进展。在Raf／MEK／ERK信号传导通路中，Raf激酶发挥着至关重要的作用。尽管在正常组织中Raf激酶的功能尚未明朗，但现有的基础及临床研究结果均显示，Raf基因的上调及其蛋白的过度表达存在于多种实体肿瘤之中，包括肾细胞癌、肝细胞癌、黑色素瘤以及非小细胞肺癌等。索拉非尼是全球首个口服的Raf激酶抑制剂。此外，作为一个多靶点药物，索拉非尼同时具有针对包括VEGFR与PDGFR的广泛酪氨酸激酶受体抑制功能。目前美国FDA已经批准索拉非尼用于治疗转移性肾癌。另外，该药物在针对黑色素瘤、肝癌、胰腺癌以及非小细胞肺癌的临床研究中也已经显示出一定的疗效。本综述将简要说明Raf激酶在正常与肿瘤细胞中的功能以及在不同肿瘤中的作用机制，并重点介绍索拉非尼的临床应用及研究。     

Impressive efficacy of sorafenib in a patient with an hepatocellular carcinoma and a portal vein thrombosis associated with a metastatic ENT cancer

Sorafenib, a new antiangiogenic and antiproliferative agent, is currently used for hepatocellular and renal cell carcinoma. We report here the case of a patient with two cancers, a locally advanced cancer of the piriform sinus and a hepatocellular carcinoma, who was given sorafenib. Tumor response of both cancers might suggest that sorafenib could be effective against head and neck cancer.

     

Does axitinib (AG-01376) have a future role in metastatic renal cell carcinoma and other malignancies?

Axitinib (Pfizer Inc., UK) is an oral small-molecule receptor tyrosine kinase inhibitor that targets angiogenesis. Axitinib has greater affinity and is a more selective inhibitor of VEGF receptor 1, -2 and -3, PDGFR and c-KIT than both sunitinib and sorafenib. It has encouraging efficacy and safety data in Phase II trials for metastatic renal cell carcinoma and advanced thyroid cancer patients. It is now being investigated in two Phase III trials in metastatic renal cell carcinoma and in Phase II trials in a range of tumor types. These trials will determine whether axitinib is an effective and safe antiangiogenic therapy.     

Role of Raf kinase in cancer: therapeutic potential of targeting the Raf/MEK/ERK signal transduction pathway

Improvements in our understanding of the molecular basis of cancer have led to the clinical development of protein kinase inhibitors, which target pivotal molecules involved in intracellular signaling pathways implicated in tumorigenesis and progression. These novel targeted agents have demonstrated activity against a wide range of solid tumors, are generally better tolerated than standard chemotherapeutics, and may revolutionize the management of advanced refractory cancer. The ubiquitous Raf serine/threonine kinases are pivotal molecules within the Raf/mitogen extracellular kinase (MEK)/extracellular signal-related kinase (ERK) signaling pathway, which regulates cellular proliferation and survival. Raf kinase isoforms (wild-type Raf-1 or the b-raf V600E oncogene) are overactivated in a variety of solid tumor types, including renal cell carcinoma (RCC), hepatocellular carcinoma (HCC), non-small cell lung cancer (NSCLC), melanoma, and papillary thyroid carcinoma. In this review, the role of Raf in normal cells and in cancer is discussed, and an overview is given of Raf inhibitors currently in development, focusing on sorafenib tosylate (BAY 43-9006 or sorafenib). Sorafenib is the first oral multi-kinase inhibitor to be developed that targets Raf kinases (Raf-1, wild-type B-Raf, and b-raf V600E), in addition to receptor tyrosine kinases associated with angiogenesis (vascular endothelial growth factor receptor [VEGFR]-2/-3, platelet-derived growth factor receptor [PDGFR]-beta) or tumor progression (Flt-3, c-kit). Preclinical and clinical sorafenib data that led to its recent approval for the treatment of advanced RCC are summarized, along with current thinking on sorafenib's mechanism of effect on the tumor and tumor vasculature in melanoma and RCC.     

Safety, pharmacokinetics, and preliminary antitumor activity of sorafenib: a review of four phase I trials in patients with advanced refractory solid tumors

Sorafenib is an oral multikinase inhibitor that inhibits Raf serine/threonine kinases and receptor tyrosine kinases involved in tumor growth and angiogenesis. It has demonstrated preclinical and clinical activity in several tumor types. Sorafenib 400 mg twice daily (bid) has been approved in several countries worldwide for the treatment of renal cell carcinoma. This review summarizes key safety, pharmacokinetic, and efficacy data from four phase I, single-agent, dose-escalation studies with sorafenib in patients with advanced refractory solid tumors (n = 173). These trials followed different treatment regimens (7 days on/7 days off, n = 19; 21 days on/7 days off, n = 44; 28 days on/7 days off, n = 41; or continuous dosing, n = 69) to establish the optimum dosing schedule. Sorafenib was generally well tolerated; most adverse events were mild to moderate in severity up to the defined maximum-tolerated dose of 400 mg twice daily (bid). The most frequently reported drug-related adverse events at any grade included fatigue (40%), anorexia (35%), diarrhea (34%), rash/desquamation (27%), and hand-foot skin reaction (25%). Sorafenib demonstrated preliminary antitumor activity, particularly among patients with renal cell carcinoma or hepatocellular carcinoma: overall, two of 137 evaluable patients achieved partial responses and 38 (28%) had stable disease. Although there was high interpatient variability in plasma pharmacokinetics across these studies, this was not associated with an increased incidence or severity of toxicity. Preliminary studies suggest that phosphorylated extracellular signal-related kinase in tumor cells or peripheral blood lymphocytes may be a useful biomarker for measuring and, ultimately, predicting the effects of sorafenib. Based on these findings, continuous daily 400 mg bid sorafenib was chosen as the optimal regimen for phase II/III studies. Trials are ongoing in renal cell carcinoma, hepatocellular carcinoma, melanoma, and non-small cell lung cancer.     

Safety and tolerability of sorafenib in clear-cell renal cell carcinoma: a Phase III overview

This review summarizes the safety of sorafenib, an oral multikinase inhibitor, focusing on the randomized, placebo-controlled, Phase III Treatment Approaches in Renal Cancer Global Evaluation Trial (TARGET) in renal cell carcinoma, which formed the basis of the approval of sorafenib. Similar to other targeted agents, sorafenib acts primarily to induce disease stabilization, rather than tumor regression, suggesting that long-term administration is necessary. The tolerability of an agent is important in long-term treatment, and a predictable and manageable side-effect profile is advantageous. Although IL-2 and interferon have been standard care treatments for advanced renal cell carcinoma for over a decade, they are poorly tolerated. Targeted agents offer an alternative for patients with advanced renal cell carcinoma, as initial therapy or after failure of cytokine treatment.     

Clinical presentation and management of hand-foot skin reaction associated with sorafenib in combination with cytotoxic chemotherapy: experience in breast cancer

Current combination therapies for advanced breast cancer provide a modest survival benefit but with greater toxicity than with monotherapies. New combinations are needed that improve the efficacy of current treatments and have acceptable tolerability profiles. Recent clinical trials have assessed the efficacy and safety of the multikinase inhibitor sorafenib in combination with common treatments for advanced breast cancer. Sorafenib has both antiangiogenic and antiproliferative activities and is indicated for patients with unresectable hepatocellular and advanced renal cell carcinoma. Generally, sorafenib is associated with manageable, non-life-threatening adverse events. One of the more common adverse events seen with sorafenib is hand-foot skin reaction, a dermatologic toxicity usually localized to the pressure points of the palms and soles. Although hand-foot skin reaction is reversible and not life threatening, it can have a significant impact on a patient's quality of life and may necessitate dose modification. Moreover, sorafenib is being evaluated in combination with breast cancer treatments that are associated with a similar dermatologic toxicity (e.g., capecitabine-induced hand-foot syndrome). This review looks at the use of sorafenib in combination with selected chemotherapies in patients with advanced breast cancer and considers the incidence, prevention, and management of hand-foot skin reaction.     

Sorafenib: key lessons from over 10 years of experience

Introduction: In 2005, sorafenib was the first targeted therapy approved for advanced renal cell carcinoma (RCC), transforming treatment. In hepatocellular carcinoma (HCC), for more than a decade, sorafenib remained the only approved systemic therapy to have demonstrated a survival benefit in first-line unresectable HCC. In 2013, sorafenib was the first targeted agent approved for patients with differentiated thyroid cancer (DTC) refractory to radioactive iodine treatment.

Areas covered: This review discusses the development, advances, and challenges associated with sorafenib use in RCC, HCC, and DTC over the past decade. A search was performed on PubMed and key congresses as required, with no time limits.

Expert commentary: Sorafenib has had a lasting impact on the therapeutic landscape of RCC, HCC, and DTC, and remains an important treatment option despite a rapidly evolving treatment landscape. Extensive clinical and real-world experience has been invaluable in improving patient management and maximizing benefit from treatment. Ongoing clinical trials continue to evaluate sorafenib in different settings, and in combination with other therapies in HCC and DTC. We have no doubt that sorafenib will continue to be an important treatment option in the coming years.     

Molecular targeted therapies for cancer: sorafenib mono-therapy and its combination with other therapies (review)

Sorafenib is an oral multikinase inhibitor that acts by inhibiting tumor growth and disrupting tumor microvasculature through antiproliferative, anti-angiogenic and proapoptotic effects. It exerts these effects via inhibition of multiple targets including Raf serine/threonine kinases, vascular endothelial growth factor receptor tyrosine kinases; VEGFR-1, VEGFR-2, VEGFR-3 and platelet-derived growth factor receptor?β (PDGFR-β). Current literature shows that the deregulated signaling through these receptors is commonly seen in human tumors. In addition, sorafenib is also shown to induce apoptosis through downregulation of Mcl-1 in many cancer types. Hence, sorafenib as a single agent has shown promising activity in some cancers such as renal cell carcinoma (RCC), hepatocellular carcinoma (HCC) and thyroid cancers. Currently, the drug holds FDA approval for the treatment of advanced RCC and unresectable HCC. However, many clinical studies have indicated several limitations to the application of sorafenib as a single agent in various other cancers. Owing to these reasons and the potential of sorafenib to synergize with other anticancer therapies, its combination with other targeted agents and chemotherapy has been widely explored with promising results. In addition, it has also shown synergistic results when combined with radiation. This review summarizes the current basic and clinical studies on the effects and mechanisms of sorafenib either administered alone or in combination with other anticancer treatments.     

Outcomes and prognosis in advanced renal cell carcinoma

Breakthroughs in understanding the pathogenesis of renal cell carcinoma have led to recent therapeutic advances in this disease. However, the US FDA approval of sunitinib and sorafenib (and soon temsirolimus) after successful Phase III trials must also be attributed to the work of clinical investigators over the past decade defining the outcomes and major prognostic factors in patients with advanced renal cell carcinoma. Those past studies have been critical in providing a context for the interpretation of future trials with novel agents, optimizing patient selection for specific therapeutic approaches and identifying appropriate variables for patient stratification on randomized trials. This review will focus on studies that define the outcome and prognosis in advanced renal cell carcinoma.     

Two cases of recurrent ovarian clear cell carcinoma treated with sorafenib

Sorafenib is an oral multikinase inhibitor targeting Raf and other kinases. The anti-tumor effect of sorafenib is thought to be mediated through its inhibition of the RAS–Raf–Erk pathway, as well as its inhibition of VEGFR and PDGFR. Sorafenib has been effective at treating patients with renal cell carcinoma (RCC). Ovarian clear cell carcinoma (OCCC) is a chemoresistant subtype of ovarian cancer. OCCC is represented by cells with clear cytoplasm that resemble those observed in RCC. Using a microarray database, the gene expression profile of OCCC was similar to that of RCC. The effects of sorafenib against human OCCC are unknown. Therefore, we used sorafenib to treat two patients with recurrent chemoresistant OCCC, and observed good effect in both of them without severe side effects. We believe that sorafenib is an effective agent against OCCC. Given the chemoresistant nature of this tumor, this drug appears to be very valuable.