Clinical Outcome in Metastatic Renal Cell Carcinoma Patients After Failure of Initial Vascular Endothelial Growth Factor-Targeted Therapy

Time on Therapy for at Least Three Months Correlates with Overall Survival in Metastatic Renal Cell Carcinoma

With 15 drugs currently approved for the treatment of metastatic renal cell carcinoma (mRCC) and even more combination regimens with immunotherapy on the horizon, there remains a distinct lack of molecular biomarkers for therapeutic efficacy. Our study reports on real-world clinical outcomes of mRCC patients from a tertiary academic medical center treated with empirically selected standard-of-care therapy. We utilized the Stanford Renal Cell Carcinoma Database (RCCD) to report on various outcome measures, including overall survival (OS) and the median number of lines of targeted therapies received from the time of metastatic diagnosis. We found that most metastatic patients did not survive long enough to attempt even half of the available targeted therapies. We also noted that patients who failed to receive a clinical benefit within the first two lines of therapy could still go on to experience clinical benefit in later lines of therapy. The term, “clinical benefit” was assigned to a line of therapy if a patient remained on drug treatment for three months or longer. Moreover, patients with clinical benefit in at least one line of therapy experienced significantly longer OS compared to those who did not have clinical benefit in at least one line of therapy. Developing biomarkers that identify patients who will receive clinical benefit in individual lines of therapy is one potential strategy for achieving rational drug sequencing in mRCC.

Real-world evidence in metastatic renal cell carcinoma

Real-world evidence has played an important role in expanding our knowledge on the treatment and prognostication of advanced renal cell carcinoma. This type of data has been particularly helpful in providing a better understanding of groups that are traditionally excluded from randomized controlled trials. The International mRCC Database Consortium (IMDC) represents the largest collection of real-world data on patients with advanced kidney cancer treated with targeted therapies. The IMDC prognostic model has been used to stratify patients in contemporary clinical trials and to provide risk-directed treatment selection in everyday clinical practice. More recently, it has been shown to predict response to first-line combination immunotherapy in the phase III CheckMate 214 clinical trial. In this review, we highlight the real-world evidence associated with the treatment of mRCC. We focus on first-line therapy, as well as second-line and third-line therapeutic options, including novel immuno-oncology agents. We also address the real-world evidence for the use of cytoreductive nephrectomy in advanced renal cell carcinoma in the targeted therapy era.

Alternative Response Criteria and Clinical Risk Factors for Assessing Tumor Response in Patients With Metastatic Renal Cell Carcinoma Who Are Receiving Salvage Therapy

OBJECTIVE

The purpose of this study is to compare the prognostic value of various solid tumor response criteria as well as the additive value of clinical risk factors in patients with advanced renal cell carcinoma (RCC).

MATERIALS AND METHODS

Two sets of CT scans (pretreatment scans and scans obtained 1-3.5 months after treatment) were reviewed for 57 patients with metastatic RCC treated with pazopanib in the salvage setting. Tumor response on the posttherapy scan was evaluated using Response Evaluation Criteria in Solid Tumors (RECIST) and Choi, modified Choi (mChoi), MASS (Morphology, Attenuation, Size, and Structure), and 10% threshold criteria. In addition, combined Memorial Sloan-Kettering Cancer Center (MSKCC) risk factors plus imaging criteria were used to define response groups. Response evaluations using these criteria were correlated with overall survival (OS) and progression-free survival (PFS), with use of the log-rank test.

RESULTS

Patients classified as having progressive disease (PD) on the basis of RECIST, mChoi, and MASS criteria had a significantly worse OS than patients with stable disease (SD) and partial response (PR). With the addition of MSKCC risk factors, all groups with PD defined by combined criteria had significantly worse OS. For 37 patients with no or one MSKCC risk factor, response groups defined by Choi, mChoi, MASS, and 10% threshold criteria did not differ in PFS or OS. However, among 20 patients with two to three MSKCC risk factors, those classified as having PR had longer PFS than did those with SD and had longer OS than did those with PD.

CONCLUSION

For patients with advanced RCC for which prior therapies have failed, the prognostic value of various imaging-based tumor response criteria differs on the basis of the MSKCC clinical risk status.

Genitourinary tumours in the targeted therapies era: new advances in clinical practice and future perspectives

Genitourinary cancers represent a heterogeneous group of malignancies arising from genitourinary tract, and are responsible for almost 359 000 newly diagnosed cases and 58 420 related deaths in USA. Continuous advances in cancer genetics and genomics have contributed towards changing the management paradigms of these neoplasms. Neoangiogenesis, through the activation of the tyrosine-kinase receptors signalling pathways, represents the key mediator event in promoting tumour proliferation, differentiation, invasiveness and motility. In the last decade, several treatments have been developed with the specific aim of targeting different cell pathways that have been recognized to drive tumour progression. The following review attempts to provide a comprehensive overview of the literature, focusing on new advances in targeted therapies for genitourinary tumours. Furthermore, the promising results of the latest clinical trials and future perspectives will be discussed.

Development of Novel Patient-Derived Preclinical Models from Malignant Effusions in Patients with Tyrosine Kinase Inhibitor-Resistant Clear Cell Renal Cell Carcinoma

PURPOSE

Although targeting angiogenesis with tyrosine kinase inhibitors (TKIs) has become standard of care in the treatment of clear cell renal cell carcinoma (RCC), resistance mechanism are not fully understood, and there is a need to develop new therapeutic options overcoming them.

METHODS AND MATERIALS

To develop a preclinical model that predicts clinical activity of novel agents in 19 RCC patients, we established patient-derived cell (PDC) and xenograft (PDX) models derived from malignant effusions or surgical specimen.

RESULTS

Successful PDCs, defined as cells that maintained growth following two passages, were established in 5 of 15 malignant effusions and 1 of 4 surgical specimens. One PDC, clinically refractory to TKIs, was implanted and engrafted in mice, resulting in a comparable histology to the primary tumor. The PDC-PDX model also showed similar genomic features when tested using targeted sequencing of cancer-related genes. When we examined the drug effects of the PDX model, the tumor cells showed resistance to TKIs and everolimus in vitro.

CONCLUSION

The results suggest that the PDC-PDX preclinical model we developed using malignant effusions can be a useful preclinical model to interrogate sensitivity to targeted agents based on genomic alterations.

Patterns of care among patients receiving sequential targeted therapies for advanced renal cell carcinoma: A retrospective chart review in the USA

OBJECTIVES

To assess real-world treatment patterns of targeted therapies after failure of first-line tyrosine kinase inhibitors in patients with advanced renal cell carcinoma.

METHODS

A large, retrospective review of medical charts of patients with advanced renal cell carcinoma in the USA was carried out. Descriptive statistics were used to summarize physicians' and patients' characteristics, treatment sequences, and reasons for treatment choices. P-values were calculated using χ² -tests for categorical variables and Wilcoxon rank-sum tests for continuous variables. A descriptive comparison was carried out between current results and those of a previous treatment pattern study conducted in 2012 to identify changes in treatment patterns over time.

RESULTS

Sunitinib and everolimus remained the most commonly-used first and second targeted therapies, respectively. Among patients who continued to a third targeted therapy, everolimus and axitinib were the most commonly-used treatments after second targeted therapy with a tyrosine kinase inhibitor and a mammalian target of rapamycin inhibitor, respectively. The use of pazopanib as first targeted therapy, and of axitinib and sorafenib as second targeted therapies, increased over time. Efficacy, treatment guidelines and a different mechanism of action were the main reasons given by physicians for choosing among second targeted therapies after failure of a first tyrosine kinase inhibitor.

CONCLUSIONS

The results of the present study document patterns of care during a period of rapid and ongoing therapeutic advancement in advanced renal cell carcinoma. Sequencing of therapies warrants ongoing analysis in light of new agents entering the advanced renal cell carcinoma treatment landscape.

The ribosomal protein S6 in renal cell carcinoma: functional relevance and potential as biomarker

Inhibitors of the mTOR pathway, such as everolimus, are promising compounds to treat patients with renal cell carcinomas (RCCs). However, the precise mechanisms of action are far from clear, and biomarkers predicting the response to mTOR inhibitors are still missing. Here, we provide evidence that in RCCs the rpS6 protein is the major mediator of anti-tumoral effects exerted by everolimus. Inhibition of mTOR signaling results in substantially decreased clonogenicity and proliferation of RCC cells, but did not significantly induce apoptosis. Everolimus effectively blocked protein biosynthesis both in vitro and in a novel ex vivo tissue slice model using fresh vital human RCC tissue. Compared to other components of the mTOR pathway, phosphorylation of rpS6 was most effectively downregulated by everolimus. Importantly, siRNA-mediated downregulation of rpS6, but not of 4ebp1 or p27, abolished the inhibitory effects of everolimus on proliferation and protein synthesis. Moreover, we analyzed the tissue expression of phosphorylated rpS6 (p-rpS6) and non-phosphorylated rpS6 in a large collection of patients with RCCs (n=598 and n=548, respectively). Expression of both proteins qualified as independent negative prognostic markers with a substantially shorter survival of patients with RCCs exhibiting high levels of rpS6 and p-rpS6. Taken together, our functional studies identified rpS6 as a main mediator of the anti-tumoral activity of Everolimus. Therefore, further (pre-)clinical evaluations of rpS6 as a predictive marker for everolimus-based treatment for RCC patients are warranted. Finally, the combined detection of phosphorylated and non-phosphorylated rpS6 could represent a robust prognostic marker to identify patients with high risk RCCs.

The Wide Experience of the Sequential Therapy for Patients with Metastatic Renal Cell Carcinoma

Sequential targeted therapies are the standard of care for patients with metastatic renal cell carcinoma (mRCC). Several drugs are available for patients whose disease progresses while they receive initial tyrosine kinase inhibitor (TKI) therapy; these include nivolumab (an inhibitor of PD-1 receptor), everolimus (an inhibitor of the mechanistic target of rapamycin) or additional TKIs. Until now, there has been no clinical evidence to support the use of one strategy versus another, so investigators and physicians rely on experience, judgement and findings from molecular analyses to select the appropriate treatment. However, with the arrival of nivolumab and cabozantinib that provide an overall survival higher than other alternative treatments, therapeutic strategies may have changed. Here, we discuss findings from preclinical and clinical studies that might help clinicians to choose the optimal treatment approach for patients with mRCC who progress to initial therapy.

Feasibility, efficacy and safety of tyrosine kinase inhibitor treatment in hemodialyzed patients with renal cell cancer: 10 years of experience

AIMS

Sine efficiency of tyrosine kinase inhibitor (TKI) therapy in dialyzed patients is still unclear we aim to analyze the outcome of treatment in such cohort.

PATIENTS & METHODS

We analyzed treatment outcomes of patients with clear cell renal cell carcinoma (ccRCC) with special focus on those who were also treated with hemodialysis and described treatment safety and progression-free survival of eight patients treated with TKIs and hemodialysis.

DISCUSSION & CONCLUSION

Our report supports statement that TKI treatment of dialyzed patients is safe and effective. ccRCC increases risk of developing renal insufficiency as well as end-stage renal disease that require dialysis. Introduction of multitargeted receptor kinase inhibitors (TKIs), including sunitinib, sorafenib and pazopanib significantly expanded life time expectancy of metastatic renal clear cell carcinoma. The advance also applies to patients with ccRCC and end-stage renal disease who undergo dialyses.

Intrinsic resistance to sunitinib in patients with metastatic renal cell carcinoma

AIM

Although targeting angiogenesis with vascular endothelial growth factor receptor (VEGFR) inhibitors has demonstrated efficacy in the treatment of renal cell carcinoma, primary, intrinsic resistance to the VEGFR inhibitor sunitinib is not fully understood in a subset of metastatic RCC (mRCC) patients.

METHODS

Between 2008 and 2012, a total of 134 patients with mRCC were treated with first-line sunitinib at one of six tertiary centers. Patients in whom progressive disease was the best response were classified as the intrinsic resistance group. Univariate and multivariate analyses were performed on the recognized baseline parameters.

RESULTS

Among 134 patients, 33 (25%) intrinsically resistant to sunitinib were identified. Multivariate logistic regression analyses revealed that the number of metastatic sites (OR = 3.6) and neutrophilia (OR = 7.4) were independently associated with development of intrinsic resistance. There were significant differences with regard to overall survival (P = 0.001) and progression-free survival (P < 0.0001) between the patients with and without intrinsic resistance.

CONCLUSIONS

Intrinsic resistance to first-line sunitinib treatment is associated with a dismal prognosis in mRCC patients. Patients with known high-risk factors (poor performance, neutrophilia, elevated lactate dehydrogenase) and multiple metastatic sites including the liver may experience a limited benefit from sunitinib. Greater understanding of the underlying mechanism and molecular biomarkers for detecting intrinsically resistant disease is needed.

Axitinib in the treatment of renal cell carcinoma: patient selection and perspectives

BACKGROUND

Axitinib is a next-generation, selective tyrosine kinase inhibitor targeting the vascular endothelial growth factor receptors. It is approved for the treatment of metastatic renal cell carcinoma (mRCC) based on a demonstrated progression-free survival advantage over sorafenib in the second-line treatment setting. However, given the variety of available targeted therapies for mRCC, appropriate patient selection for the available therapies remains a significant clinical challenge.

PURPOSE

This review summarizes the available evidence on the clinical, toxicity, and pharmacologic considerations for determining appropriate patient selection for axitinib therapy. In addition, it describes recent data on the use of predictive biomarkers to guide clinical management. This paper consists of material obtained via PubMed and Medline literature searches through October 2015.

CONCLUSION

Axitinib has a well-established role in the management of mRCC. Consistent clinical efficacy has been demonstrated across prognostic risk groups and prior therapeutic exposures. Although axitinib is generally well tolerated, appropriate toxicity management is critical to maximizing drug delivery and optimizing treatment outcomes. Although incident hypertension has been associated with improved clinical outcomes on axitinib, there are currently no validated clinical or genetic predictive biomarkers to guide patient selection.

Sequence of treatment in locally advanced and metastatic renal cell carcinoma

The spectrum of drugs that have shown activity in advanced or metastatic renal cell carcinoma (RCC) has led to a debate on the optimal sequence of treatments. There is agreement on recommending targeted agents as the standard of care in this disease. Uncertainty, however, remains on the best first-line drug choice. Physicians and patients may select sunitinib, bevacizumab in combination with interferon-alpha (IFN-α), pazopanib, or-in poor risk patients-temsirolimus. There are also a variety of therapies with proven efficacy on hand in the second-line setting: sorafenib, pazopanib, axitinib, and everolimus. While most randomized RCC trials assessed progression free survival (PFS) as primary endpoint, some agents were shown to improve median overall survival (OS), and given in sequence they have extended the life expectancy of RCC patients from 13 months in the cytokine era to over 30 months. Despite the progress made, there are sobering aspects to the oncologic success story in RCC, as the new treatments do not obtain an objective response or disease stabilization (SD) in all patients. There are also as yet no predictors to select patients who might benefit and those who are primary resistant to specific drugs, and ultimately almost all patients will experience disease progression. Bearing inevitable treatment failure in mind, availability of further drugs and switching therapy while the patient is in a condition to continue pharmacotherapy is essential. Of note, depending on the setting, only 33-59% of patients receive second-line treatment. In this review we present data on first-, second-, and third-line treatment in RCC, and discuss the difficulties in their interpretation in the context of treatment sequence. We summarize biological aspects and discuss mechanisms of resistance to anti-angiogenic therapy and their implications for treatment selection.

Pharmacoeconomic and clinical implications of sequential therapy for metastatic renal cell carcinoma patients in Central and Eastern Europe

INTRODUCTION

The incidence and mortality rates of kidney cancer in the Central and Eastern European (CEE) region are among the highest in the world. Access to second and subsequent lines of metastatic renal cell carcinoma (mRCC) therapies is highly varied in the region. Despite the increasing body of evidence supporting the clinical benefit of multiple lines of treatment, access to treatment beyond first line is restricted in many of these countries.

AREAS COVERED

The adoption of targeted therapies for the first-line treatment of mRCC in the region was slow and faced many obstacles. In order to evaluate the current status of treatment beyond the first-line setting in the CEE region, this review examines the availability and reimbursement of mRCC drugs and clinical practice in institutions that treat patients with mRCC.

EXPERT OPINION

This review highlights the need to raise awareness among physicians, payers and regulators on clinical trial and cost-effectiveness data regarding the treatment of mRCC beyond the first line. The obstacles to mRCC drug access highlighted in this review need to be overcome to ensure that patients are receiving the best treatment available.

Improving outcomes in metastatic clear cell renal cell carcinoma by sequencing therapy

Targeted agents have substantially improved outcomes in metastatic clear cell renal cell carcinoma. However, due to multiple mechanisms of evasive resistance, almost all patients progress at some point and may require subsequent therapies. Various agents have been explored after failure of first-line treatment in randomized clinical trials. However, so far few questions about the optimal sequence have been answered. Both everolimus and axitinib have been considered standard of care after failure of first-line VEGF-TKI; sorafenib has been proposed as an additional option. In clinical practice, several factors may influence the choice of subsequent treatment: these include considerations on appropriate drug exposure in first-line, gained insights on prognostic and predictive factors as well as mechanisms of resistance. Once the decision in second-line has been made and treatment has been initiated, treating physicians may already be challenged by the question of what to offer in third- and later lines. Treatment beyond second-line treatment isn't supported by strong evidence, and at this stage of disease, retrospective reports on rechallenge may help to guide decisions. In addition, local treatment approaches including metastasectomy and stereotactic radiosurgery may help to optimize outcomes in all treatment lines.

Prognostic factors in second-line targeted therapy for metastatic clear-cell renal cell carcinoma after progression on an anti-vascular endothelial growth factor receptor tyrosine kinase inhibitor

BACKGROUND

About 40% of metastatic clear-cell renal cell carcinoma (m-ccRCC) patients receive a second-line targeted therapy after failure of anti-vascular endothelial growth factor receptor tyrosine kinase inhibitors (anti-VEGFR-TKI). Efficacy of second-line therapy is usually limited and prognostic and predictive factors at the start of second-line therapy are lacking. To identify the subgroup of patients that will benefit from such treatment remains a challenge.

METHODS

We performed a multi-institutional, retrospective study of patients who received a second-line therapy after progression on an anti-VEGFR-TKI. Univariate and multivariate analyses were performed in order to identify prognostic factors for progressive disease (PD) as best response, progression-free survival (PFS) and overall survival (OS) on second-line therapy.

RESULTS

For the whole cohort of 108 patients, mOS from the start of second-line therapy was 8.9 months while mPFS on second-line therapy was 2.8 months. A total of 49/105 (47%) patients had PD, 50/105 (48%) stable disease (SD) and 6/105 (6%) a partial response (PR). On multivariate analysis, the following markers were associated with improved outcome on second-line therapy: a PFS on first-line therapy ≥12 months (HR for PFS: 1.961; p = 0.008) (HR for OS: 1.724; p = 0.037) and Fuhrman grade 1-2 tumors (HR for OS: 2.198; p = 0.007). Markers associated with poorer outcome on second-line therapy were: elevated serum lactate dehydrogenase (LDH) levels (HR for PFS: 0.511; p = 0.04) (HR for OS: 0.392; p = 0.017), low albumin (HR for OS: 0.392; p = 0.01) and elevated corrected calcium levels (HR for OS: 0.416; p = 0.01). The impact on OS of the Memorial Sloan Kettering Cancer Centre (MSKCC) and International Renal Cell Carcinoma Database Consortium (IMDC) prognostic scores as calculated at start of second-line therapy was validated in our patient series.

CONCLUSIONS

Duration of first-line PFS, Fuhrman grade, serum LDH levels, albumin levels, corrected calcium levels and the MSKCC and IMDC scores calculated at start of second-line therapy are prognostic factors for m-ccRCC patients treated with second-line targeted therapy.

Clinical experience with everolimus in the second-line treatment of advanced renal cell carcinoma

Everolimus is an oral inhibitor of mammalian target of rapamycin (mTOR-I) and is currently approved for the treatment of metastatic renal cell carcinoma (mRCC) after failure of first-line vascular endothelial growth factor receptor tyrosine kinase inhibitor (TKI). In this narrative review, we aim to report the available evidence about the use of everolimus as second-line therapy for mRCC. A literature search was performed using PubMed/MEDLINE and abstracts from major conferences on clinical oncology as sources. We report data from prospective as well as retrospective and real world data studies and we analyze the safety and efficacy profile of everolimus as second-line therapy for mRCC. Although different drugs are currently available for the second-line treatment of mRCC, everolimus represents a feasible and safe option in this setting, especially for patients who have experienced high-grade toxicity or are still carrying TKI-related toxicities from first-line treatment.

Future perspectives for mTOR inhibitors in renal cell cancer treatment

ABSTRACT 

Everolimus is a mTOR inhibitor that demonstrates antitumor and antiangiogenic activities. In a randomized Phase III trial, patients with metastatic renal cell carcinoma who progressed on sunitinib/sorafenib were treated with everolimus and showed significant improvement in progression-free survival compared with best supportive care. Novel approaches in treatment are expected to ensure less toxic therapies and increase efficacy of everolimus. To provide a new perspective for mTOR inhibitor research and therapy, we discuss renal cell carcinoma cancer stem cells as a potential target for mTOR inhibitors and present new concepts on emerging antiangiogenic therapies. Finally, we point why systems biology approach with reverse molecular engineering may also contribute to the field of drug discovery in renal cell carcinoma.

The International Metastatic Renal Cell Carcinoma Database Consortium model as a prognostic tool in patients with metastatic renal cell carcinoma previously treated with first-line targeted therapy: a population-based study

BACKGROUND

Previous prognostic models for second-line systemic therapy in patients with metastatic renal cell carcinoma have not been studied in the setting of targeted therapy. We sought to validate the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) model in patients with metastatic renal cell carcinoma receiving next-line targeted therapy after progression on first-line targeted therapy.

METHODS

In this population-based study, we analysed patients who received second-line targeted therapy for metastatic renal cell carcinoma at 19 centres in Canada, USA, Greece, Japan, Singapore, South Korea, and Denmark. The primary endpoint was overall survival since the initiation of second-line therapy. We compared the prognostic performance of the IMDC model with the three-factor MSKCC model used for previously treated patients for overall survival since the start of second-line targeted therapy.

FINDINGS

Between Jan 1, 2005, and Nov 30, 2012, we included 1021 patients treated with second-line targeted therapy. Median overall survival since the start of second-line targeted therapy was 12·5 months (95% CI 11·3-14·3). Five of six predefined factors in the IMDC model (anaemia, thrombocytosis, neutrophilia, Karnofsky performance status [KPS] <80, and <1 year from diagnosis to first-line targeted therapy) were independent predictors of poor overall survival on multivariable analysis. The concordance index using all six prognostic factors (ie, also including hypercalcaemia) was 0·70 (95% CI 0·67-0·72) with the IMDC model and was 0·66 (95% CI 0·64-0·68) with the three-factor MSKCC model. When patients were divided into three risk categories using IMDC criteria, median overall survival was 35·3 months (95% CI 28·3-47·8) in the favourable risk group (n=76), 16·6 months (14·9-17·9) in the intermediate risk group (n=529), and 5·4 months (4·7-6·8) in the poor risk group (n=261).

INTERPRETATION

The IMDC prognostic model can be applied to patients previously treated with targeted therapy, in addition to previously validated populations in first-line targeted therapy. The IMDC prognostic model in the second-line targeted therapy setting has an improved prognostic performance and is applicable to a more contemporary patient cohort than that of the three-factor MSKCC model.

FUNDING

DF/HCC Kidney Cancer SPORE P50 CA101942-01, Kidney Cancer Research Network of Canada, Canadian Institute for Health Research, Trust Family, Loker Pinard, Michael Brigham, and Gerald DeWulf.

Comparative effectiveness of second-line targeted therapies for metastatic renal cell carcinoma: synthesis of findings from two multi-practice chart reviews in the United States

BACKGROUND

Second-line targeted therapies for metastatic renal cell carcinoma (mRCC) include mammalian target of rapamycin (mTOR) inhibitors and tyrosine kinase inhibitors (TKIs). This study compares the effectiveness of these therapies in a multi-practice chart review and synthesizes the findings with those of a similarly designed study.

METHODS

Medical oncologists/hematologists (N = 36) were recruited to review charts for patients aged ≥18 years, received a first-line TKI and initiated second-line targeted therapy in 2010 or later. The primary outcome was time from second-line initiation to treatment failure (TTF; discontinuation, physician-assessed progression, or death, whichever occurred first). TTF was compared among patients receiving second-line everolimus (EVE), temsirolimus (TEM), or TKI as a class, using a Cox proportional hazards model adjusting for type of initial TKI and response, histological subtype, performance status, and sites of metastasis. Hazard ratios (HRs) for TTF were pooled, in a meta-analysis, with previously reported HRs for progression-free survival from a chart review with a similar design.

RESULTS

A total of 138, 64 and 79 patients received second-line therapy with EVE, TEM or a TKI, respectively. Adjusting for baseline characteristics, EVE was associated with numerical, but not statistically significant, reductions of 28% (HR = 0.72; 95% CI [0.45-1.16]) and 26% (HR = 0.74; 95% CI [0.48-1.15]) in the hazard of TTF compared to TEM and TKI, respectively. After pooling the HRs from both studies, EVE was associated with significantly reduced hazards of TTF compared to TEM and TKI (HR = 0.73; 95% CI [0.57-0.93]; and HR = 0.75; 95% CI [0.57-0.98], respectively).

LIMITATIONS

LIMITATIONS include retrospective analyses with possible missing or erroneous chart data, confounding of unobserved factors due to non-randomization, and limited data for axitinib during the study period.

CONCLUSIONS

In pooled results from two independent multi-practice chart reviews of second-line mRCC treatment, EVE was associated with significantly reduced hazards of treatment failure compared to TEM and to TKIs as a class.

Treatment patterns in metastatic renal cell carcinoma: a retrospective review of medical records from US community oncology practices

BACKGROUND

Vascular endothelial growth factor (VEGF) inhibitors, including targeted therapy with tyrosine kinase inhibitors (TKIs) and the angiogenesis inhibitor bevacizumab, and mammalian target of rapamycin (mTOR) inhibitors are now the standard of care for metastatic renal cell carcinoma (mRCC). However, real-world treatment patterns are not well characterized.

OBJECTIVE

To describe treatment patterns during the first, second, and third lines of targeted therapies for mRCC among community oncologists in the US.

METHODS

Participating physicians recruited from a nationwide panel each identified up to 15 adult mRCC patients who initiated a second therapy after January 2010. Information extracted from medical records included types of targeted therapies, reasons for treatment choices, patterns of treatment discontinuation, and dose adjustments.

RESULTS

Thirty-six physicians contributed charts from 433 mRCC patients. Seventy-seven percent of patients received a VEGF inhibitor as first targeted therapy; 23% received an mTOR inhibitor. Among first-line VEGF users, second-line treatments were 66% mTOR and 34% VEGF inhibitors. Among first-line mTOR users, second-line treatments were 94% VEGF and 6% mTOR inhibitors. Sunitinib followed by everolimus was the most commonly used treatment sequence. Estimated median duration for second targeted therapy was 8.6 months, and median overall survival (OS) and progression-free survival (PFS) were 27.4 and 10.8 months, respectively. Efficacy, treatment guidelines and mechanism of action were the most important considerations for treatment choice.

LIMITATIONS

LIMITATIONS include no adjustment for baseline characteristics, possible difference between physician-defined progression and central review in the clinical trial setting, and limited data availability for axitinib during the study period.

CONCLUSION

In this large retrospective chart review among community oncologists, VEGF-mTOR-VEGF was the most common treatment sequence for mRCC. The most common drugs were sunitinib in the first line and everolimus in the second line.

Comparative outcomes of everolimus, temsirolimus and sorafenib as second targeted therapies for metastatic renal cell carcinoma: a US medical record review

OBJECTIVE

To compare outcomes of metastatic renal cell carcinoma (mRCC) patients treated with everolimus, temsirolimus, and sorafenib following initial treatment with a tyrosine kinase inhibitor (TKI) in community and academic practices throughout the US.

RESEARCH DESIGN AND METHODS

Medical records of mRCC patients who received everolimus, temsirolimus or sorafenib as their second therapy following a TKI were retrospectively reviewed from a nationally representative panel of oncologists. Overall survival (OS) and progression-free survival (PFS) of second targeted therapies were compared using multivariable Cox proportional hazard models, with adjustment for demographics, disease severity and prior treatments.

RESULTS

A total of 233, 178, and 123 mRCC patients receiving everolimus, temsirolimus, and sorafenib, respectively, as second targeted therapies were included. Eighty-six percent used sunitinib and the remainder used sorafenib or pazopanib as their initial TKI. After adjusting for baseline characteristics, everolimus was associated with significantly prolonged OS (hazard ratio [HR] 0.60; CI 0.42-0.85; p = 0.004) and PFS (HR 0.73; CI 0.54-0.97; p = 0.032) compared to temsirolimus. Everolimus was associated with significantly longer OS (HR 0.66; CI 0.44-0.99; p = 0.045) and numerically longer PFS compared to sorafenib. No significant differences were observed between temsirolimus and sorafenib.

LIMITATIONS

Despite adjustment for multiple patient characteristics, comparisons between treatment groups may be confounded by unobserved factors in this retrospective observational study. Tolerability outcomes were not collected.

CONCLUSIONS

In this retrospective, non-randomized study of mRCC patients with prior TKI treatment, everolimus was associated with significantly prolonged OS and PFS compared to temsirolimus and significantly prolonged OS compared to sorafenib.

Sequential targeted therapy after pazopanib therapy in patients with metastatic renal cell cancer: efficacy and toxicity

INTRODUCTION/BACKGROUND

Patients with metastatic renal cell carcinoma (mRCC) in whom first-line therapies have failed might derive clinical benefit with sequential targeted agents. Limited data are available on the efficacy and toxicity of subsequent therapies after disease progression during pazopanib therapy.

PATIENTS AND METHODS

Patients with mRCC who received subsequent systemic treatment after pazopanib treatment failure were identified across 7 institutions. Pazopanib was given as first-line therapy in 28 patients and after cytokines therapy in 7 patients. Clinical outcome and toxicity analyses of 2 sequential treatment options (anti-vascular endothelial growth factor [VEGF] or mammalian target of rapamycin inhibitor [mTORi]) is presented.

RESULTS

Subsequent therapy was anti-VEGF in 22 patients and mTORi in 13. One patient who received bevacizumab and temsirolimus combination was excluded. VEGF-targeted therapies included sorafenib (n = 10), sunitinib (n = 3), bevacizumab (n = 2), cediranib (n = 4) and cabozantinib (n = 3). Patients treated with mTORi received everolimus. Median progression-free survival was 5.6 months from the start of subsequent therapy with anti-VEGF and 2.4 months with mTORi (P = .009). Overall survival (OS) was not significantly different (P = .68). Clinical benefit (including partial response and stable disease) on subsequent therapy was observed in 15 patients (64%) and 4 patients (31%) of anti-VEGF- and everolimus-treated patients, respectively (P = .021).

CONCLUSION

In this retrospective study, targeting VEGF was an effective strategy after disease progression during pazopanib treatment, although OS was not different among patients treated with VEGF or mTORi.

Optimal management of metastatic renal cell carcinoma: current status

The armamentarium for the systemic therapy of advanced renal cell carcinoma (RCC) has undergone dramatic changes over the past 6 years. While high-dose interleukin (IL)-2 remains an option for highly selected good and intermediate risk patients with clear-cell histology because of durable complete responses in a small fraction of patients, cytokine-based therapy including interferon (IFN) has been supplanted by vascular-endothelial growth factor (VEGF) and mammalian target of rapamycin (mTOR) inhibitors. Treatment decision is initially based on prognostication of the disease. As metastatic RCC (mRCC) is commonly an indolent disease, a period of observation should always been considered. For good and intermediate risk disease, pazopanib, sunitinib or the combination of bevacizumab plus IFN are considered. Notably, recent data suggest non-inferiority for the efficacy of pazopanib compared to sunitinib coupled with a better toxicity profile. A novel VEGF receptor inhibitor, tivozanib, is expected to be approved based on improvement in PFS when compared to sorafenib in the first-line setting. The use of temsirolimus for poor risk disease is supported by a phase III trial dedicated to this group of patients. The role of cytoreductive nephrectomy in the context of VEGF and mTOR inhibitors is being studied in randomized trials. Selected patients with solitary or oligometastatic disease may be eligible for metastatectomy. Following first-line VEGF inhibitors, second-line therapy with everolimus and axitinib have demonstrated benefits in progression-free survival (PFS). One phase III trial comparing sorafenib and temsirolimus in the post-sunitinib setting showed no difference in PFS, the primary endpoint, but did show a superior overall survival for sorafenib. Sorafenib, pazopanib and axitinib have all demonstrated clinical benefit following cytokines. Therapy following first-line mTOR inhibitors remains undefined, although VEGF inhibitors have demonstrated activity in this setting. Optimal sequencing of agents and individualized therapy based on biomarkers is undergoing investigation. Today, the choice of therapy is based on patient and physician decision, which is a function of comorbidities, toxicity profiles and costs. Clinical trials evaluating novel agents and combinations should be preferred when available since agents in the current therapeutic arsenal have not yielded cures despite extending median survival to greater than 2 years. One noteworthy new class of agents that has yielded durable responses is programmed death (PD)-1 inhibitors, which target a T-lymphocyte checkpoint and are heralding a resurgence of immunotherapy. Finally, optimal therapy for non-clear cell RCC remains to be delineated, although sunitinib, everolimus and other VEGFR-TKI or mTOR inhibitors have all demonstrated modest benefit.

Sequencing therapy in metastatic renal cell cancer

The sequencing of targeted therapy is well established in metastatic renal cancer. Switching between different vascular endothelial growth factor (VEGF)-targeted therapies or VEGF-targeted therapies and mammalian target of rapamycin (mTOR) inhibitors are both of proven benefit. The optimal sequence remains unclear. Unfortunately, there is a lack of biomarkers to drive decision making. In this article we review the current data and describe the treatment options for patients.

Prognostic biomarkers for patients with advanced renal cell carcinoma treated with VEGF-targeted tyrosine kinase inhibitors

Tyrosine kinase inhibitors with activity against vascular endothelial growth factor receptor 2 are now standard treatment for the majority of patients with advanced renal cell carcinoma. The clinical development of these agents followed by their broad clinical utilization has allowed the creation of large databases to facilitate the identification of prognostic biomarkers and development of prognostic models. While several clinical prognostic models have been created, work continues on identifying novel biomarkers which might be used in conjunction with or even in place of these clinical models. In this review, we discuss the progress thus far in improving on current prognostic models and speculate on possible developments in the near future.

The treating scenario in genitourinary oncology: what is new? Part 2

The objectives of this innovative meeting were to discuss developments in the management of genitourinary cancer worldwide and how Italian clinicians could harness these innovations in their everyday practice. The 2-day meeting was divided into two sessions covering kidney and prostate cancer, and a large part was given over to the presentation and discussion of new recently presented data at major international congresses in 2012. There were no restrictions on content and all subjects from pathology, surgery and genetics to therapy and patient outcomes were covered.

Prolonged exposure to tyrosine kinase inhibitors or early use of everolimus in metastatic renal cell carcinoma: are the two options alike?

We retrospectively analyzed metastatic renal cell carcinoma (RCC) patients treated with 3 targeted agents. Patients started the sequence with a tyrosine kinase inhibitor (TKI), sunitinib or sorafenib, and were divided into 2 groups based on the order in which they received the other reciprocal TKI and everolimus (EVE): TKI-TKI-EVE group (n = 19) and TKI-EVE-TKI group (n = 14). Median progression-free survival (PFS) with first TKI was 13 months in the TKI-TKI-EVE group and 10 months in the TKI-EVE-TKI group. PFS with the second agent showed a trend in favor of the TKI-TKI-EVE sequence, with a median of 11 versus 6.5 months, whereas median PFS with the third agent was 6 months in both groups. Total PFS also showed a trend in favor of the TKI-TKI-EVE sequence with a median of 31 versus 23 months. Median overall survival (OS) was 38 months in both groups, with more patients receiving subsequent treatment in the TKI-EVE-TKI group. The subgroup of patients no long-term responders (≤9 months) to first TKI showed similar outcomes irrespective of the sequence. The subgroup of long-term responders to first TKI (>9 months) who received the other TKI instead of EVE had better outcomes in terms of median PFS with the second agent (13 vs. 5.5 months; p = 0.0271), median total PFS (39.5 vs. 23.5 months; p = 0.0415), and median OS (46 vs. 38 months). In conclusion, no apparent advantage was observed with early use of EVE in advanced RCC, even in those patients who did not benefit long from first-line TKI, whereas long-term duration of first-line TKI seems to be predictor of second-line TKI efficacy.

Second line treatment of metastatic renal cell carcinoma: The Institut Gustave Roussy experience with targeted therapies in 251 consecutive patients

BACKGROUND

Sequential treatment is currently the standard of care in metastatic renal cell carcinoma (mRCC). However, very little is known on how many patients (pts) can receive second line or further, and on how to predict those pts. The goal of this study was to evaluate these questions in a large series of pts treated in our institution.

PATIENTS AND METHODS

Data from all mRCC patients treated at the IGR from 2005 to 2009 with first line targeted therapy (sunitinib (SU), sorafenib (SO), bevacizumab (B), temsirolimus or everolimus (pooled together as mammalian target of rapamycin - mTOR)) were analysed. Only patients with subsequent follow-up have been included in this analysis. Patients were defined as 'non-eligible' for second treatment if: they were (i) still on first line treatment, (ii) not showing progressive (durable stable disease or partial response or complete response) or (iii) if they refused a second line treatment.

RESULTS

251 patients, median age 60 years, median follow-up 20.2 months were treated with targeted therapy with a median overall survival (OS) of 25.8 months. Median OS with SU (127), SO (60) or B (61) were 26.3, 16.4 and 32.5 months respectively. Only three patients received an mTOR inhibitor as first line. According to the eligibility criteria, the percentage of patients who received a second line was 59% (n=61/103), 52% (n=30/58) and 79% (n=38/48) for Su, So and B, respectively. Memorial Sloan-Kettering Cancer Centre (MSKCC) classification (P=0.02) and first line agent (P=0.001) were significant predictive factor for receiving a second line of treatment. Overall, patients receiving B were in better general condition, with 77% of performance status score (PS)=0 compared to SO (53%) and SU (48%) (P=0.005). Among the 131 patients who received a second line, the median OS from the start of second line treatment was 20.8 months for a tyrosine kinase inhibitor (TKI) (n=98; 75%) and 16.6 months for an mTOR (n=32; 42%) (P=0.12). Furthermore, the percentage of patients who received a third line was 56% (27/48), 28% (7/25) and 65% (13/20) for SU, SO and B, respectively.

CONCLUSION

The median OS in patients treated with targeted therapies for mRCC in The Institut Gustave Roussy exceeds 2 years. The use of second line varies from 52% to 79%. Further studies are needed to validate the MSKCC groups and first line therapy as predictive factor for second line treatment.

Comprehensive overview of the efficacy and safety of sorafenib in advanced or metastatic renal cell carcinoma after a first tyrosine kinase inhibitor

We performed a literature search that shed light on the signaling pathways involved in the sorafenib activity as first- or subsequent-line treatment, taking into account its toxicity profile. Sorafenib appears to have better tolerability when compared with other agents in the same indication. Cross-resistance between tyrosine kinase inhibitors (TKIs) may be limited, even after failure with a previous VEGFR inhibitor, but the optimal sequence with TKIs remains to be determined. Randomized trials of second-line treatment options have showed either modest or no differences in terms of progression-free and overall survival (OS). Direct comparison between sorafenib and axitinib demonstrated differences in terms of PFS in favor of axitinib, but not in terms of OS as second-line treatment. In contrast, a phase III study showed a benefit in OS, favoring sorafenib when compared with temsirolimus. In conclusion, after using other VEGF inhibitor such as sunitinib, sorafenib is active and safe for the treatment of patients with advanced or metastatic RCC.

Therapeutic challenges in advanced renal cell carcinoma

The therapeutic landscape of advanced renal cell carcinoma has grown increasingly more complex with the recent approval of several molecularly targeted agents. While researchers focus on developing predictive algorithms and identifying novel therapeutic targets and agents, clinical practitioners continue to face many practical challenges when determining therapeutic strategies for individual patients. This review will discuss several of these challenges including patient selection strategies, sequential therapy, optimal dose and schedule of various drugs, and therapeutic options for patients with nonclear-cell renal cell carcinoma.

Evaluation of patients with metastatic renal cell carcinoma after failure of first-line treatment

The approval and use of molecular targeted agents for the first-line treatment of metastatic renal cell carcinoma (mRCC) has substantially improved the clinical outcome of patients. Although eventually all patients progress, hopes have been renewed with the approval of everolimus for patients who progress on or after treatment with tyrosine kinase inhibitors. In order to improve the prognosis for these patients, it is imperative to understand the reasons why patients with mRCC fail on first-line treatment. Currently, progression is assessed on the basis of the Response Evaluation Criteria in Solid Tumors, but it is known that targeted agents tend to cause disease stabilization rather than a significant decrease in tumor mass. Therefore, it may be time to evaluate the need to incorporate additional diagnostic methods in the assessment of disease response. Equally important is the study of the factors that determine the success or failure of second-line therapy in order to increase the chances of delivering the most effective and personalized therapy possible. In this article, we review the evidence related to the evaluation of patients with mRCC who fail on first-line treatment with targeted agents, including the systems to assess response and progression, the prognostic factors, the prognostic models that have been created based on these factors, and what is known about predictive biomarkers of disease outcome.

Safety and Efficacy of Sorafenib in Renal Cell Carcinoma

This article reviews data on sorafenib use in renal cell carcinoma. Mechanisms of actions and pharmacokinetics are briefly described. Major clinical trials are presented, summarizing efficacy and safety of sorafenib. Its place in current treatment of renal cell carcinoma is discussed. Sorafenib is likely to remain one of the mainstays of RCC treatment in coming years.

Temsirolimus: a safety and efficacy review

INTRODUCTION

The vascular endothelial growth factor (VEGF) pathway and the mammalian Target of Rapamycin (mTOR) represent the most frequently exploited targets in renal cell carcinoma (RCC). Temsirolimus is an inhibitor of mTOR, and is a unique ester derivative of sirolimus, a macrocyclic lactone, with improved pharmaceutical properties, including stability and solubility. Temsirolimus binds to the cytoplasmic protein FKBP-12, and the complex binds and inhibits mTOR.

AREAS COVERED

This review summarizes the clinical findings and safety of temsirolimus in RCC patients.

EXPERT OPINION

A Phase III clinical trial has demonstrated that temsirolimus has statistically significant advantages over treatment with IFN-α in RCC patients with poor prognosis, in terms of OS (overall survival), PFS (progression-free survival), and tumor response. Median OS was improved 49% compared to IFN-α, and median PFS was approximately doubled. It is now considered the standard for RCC patients with poor prognostic features. The possibility that this agent is useful in metastatic non-clear cell carcinoma patients has also been suggested by a subset analysis of the pivotal Phase III trial. Studies in untreated favorable and intermediate risk clear cell and refractory mRCC patients are required.

Patients with advanced and metastatic renal cell carcinoma treated with targeted therapy in the Czech Republic: twenty cancer centres, six agents, one database

The incidence and mortality of renal cell carcinoma (RCC) in the Czech Republic are among the highest in the world. Several targeted agents have been recently approved for the treatment of advanced/metastatic RCC.

OBJECTIVE

Presentation of a national clinical database for monitoring and assessment of patients with advanced/metastatic RCC treated with targeted therapy. The RenIS (RENal Information System, http://renis.registry.cz ) registry is a non-interventional post-registration database of epidemiological and clinical data of patients with RCC treated with targeted therapies in the Czech Republic. Twenty cancer centres eligible for targeted therapy administration participate in the project. As of November 2011, six agents were approved and reimbursed from public health insurance, including bevacizumab, everolimus, pazopanib, sorafenib, sunitinib, and temsirolimus. As of 10 October 2011, 1,541 patients with valid records were entered into the database. Comparison with population-based data from the Czech National Cancer Registry revealed that RCC patients treated with targeted therapy are significantly younger (median age at diagnosis 59 vs. 66 years). Most RenIS registry patients were treated with sorafenib and sunitinib, many patients sequentially with both agents. Over 10 % of patients were also treated with everolimus in the second or third line. Progression-free survival times achieved were comparable to phase III clinical trials. The RenIS registry has become an important tool and source of information for the management of cancer care and clinical practice, providing comprehensive data on monitoring and assessment of RCC targeted therapy on a national level.

Economic evaluation of first-line treatments for metastatic renal cell carcinoma: a cost-effectiveness analysis in a health resource-limited setting

Background

To estimate, from the perspective of the Chinese healthcare system, the economic outcomes of five different first-line strategies among patients with metastatic renal cell carcinoma (mRCC).

Methods and Findings

A decision-analytic model was developed to simulate the lifetime disease course associated with renal cell carcinoma. The health and economic outcomes of five first-line strategies (interferon-alfa, interleukin-2, interleukin-2 plus interferon-alfa, sunitinib and bevacizumab plus interferon-alfa) were estimated and assessed by indirect comparison. The clinical and utility data were taken from published studies. The cost data were estimated from local charge data and current Chinese practices. Sensitivity analyses were used to explore the impact of uncertainty regarding the results. The impact of the sunitinib patient assistant program (SPAP) was evaluated via scenario analysis. The base-case analysis showed that the sunitinib strategy yielded the maximum health benefits: 2.71 life years and 1.40 quality-adjusted life-years (QALY). The marginal cost-effectiveness (cost per additional QALY) gained via the sunitinib strategy compared with the conventional strategy was $220,384 (without SPAP, interleukin-2 plus interferon-alfa and bevacizumab plus interferon-alfa were dominated) and $16,993 (with SPAP, interferon-alfa, interleukin-2 plus interferon-alfa and bevacizumab plus interferon-alfa were dominated). In general, the results were sensitive to the hazard ratio of progression-free survival. The probabilistic sensitivity analysis demonstrated that the sunitinib strategy with SPAP was the most cost-effective approach when the willingness-to-pay threshold was over $16,000.

Conclusions

Our analysis suggests that traditional cytokine therapy is the cost-effective option in the Chinese healthcare setting. In some relatively developed regions, sunitinib with SPAP may be a favorable cost-effective alternative for mRCC.