Sequential use of sorafenib and sunitinib in advanced renal-cell carcinoma (RCC): an Italian multicentre retrospective analysis of 189 patient cases

Optimal sequential therapy using tyrosine kinase inhibitors as the first-line treatment in patients with metastatic renal cell carcinoma: A nationwide multicenter study

Objective

The purpose of the study was to identify the best sequence of therapy beginning with a tyrosine kinase inhibitor (TKI) as the first-line therapy for patients with metastatic renal cell carcinoma (mRCC) in terms of overall survival (OS), progression-free survival (PFS), and rates of discontinuation and adverse effects during the treatment period.

Methods

This is a retrospective, nationwide multicenter study of patients with mRCC after diagnosis at 10 different tertiary medical centers in Korea from January 1992 to December 2017. We focused on patients at either "favorable" or "intermediate" risk according to the International mRCC Database Consortium criteria, and they were followed up (median 335 days). Finally, a total of 1409 patients were selected as the study population. We generated a Cox proportional hazard model adjusted for covariates, and the different therapy schemes were statistically tested in terms of OS as well as PFS. In addition, frequencies of discontinuation and adverse events were compared among the therapy schemes.

Results

Of the primary patterns of treatment sequences (24 sequences), "sunitinib-pazopanib" and "sunitinib-everolimus-immunotherapy" showed the most beneficial results in both OS and PFS with significantly lower hazards than "sunitinib", which is the most commonly treated agent in Korea. Considering that the "TKI-TKI" structure showed relatively higher discontinuation rates with higher adverse effects, the overall beneficial sequence would be "sunitinib-everolimus-immunotherapy".

Conclusion

Among several sequential therapy starting with TKIs, "sunitinib-everolimus- immunotherapy" was found to be the best scheme for mRCC patients with "favorable" or "intermediate" risks.

Mechanisms of sunitinib resistance in renal cell carcinoma and associated opportunities for therapeutics

Sunitinib is the first-line drug for renal cell carcinoma (RCC) treatment. However, patients who received sunitinib treatment will ultimately develop drug resistance after 6-15 months, creating a huge obstacle to the current treatment of renal cell carcinoma. Therefore, it is urgent to clarify the mechanisms of sunitinib resistance and develop new strategies to overcome it. In this review, the mechanisms of sunitinib resistance in renal cell carcinoma have been summarized based on five topics: activation of bypass or alternative pathway, inadequate drug accumulation, tumour microenvironment, metabolic reprogramming and epigenetic regulation. Furthermore, present and potential biomarkers, as well as potential treatment strategies for overcoming sunitinib resistance in renal cell carcinoma, are also covered.

Cardiovascular profile of contemporary treatments of renal cell carcinoma: A single-center prospective study

BACKGROUND

Tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) have revolutionized the treatment of metastatic renal cell carcinoma (mRCC). Emerging data suggest that these agents can result in clinically significant cardiotoxicity, compromising the care.

METHODS

We conducted a prospective longitudinal study to evaluate the incidence of de novo cardiac dysfunction as assessed by echocardiography and blood biomarkers in mRCC patients receiving TKI with or without ICI followed at baseline, 3-month and 6-month. We recruited consecutive newly diagnosed mRCC patients treated at our institution between 2015 and 2018 as well as patients with localized RCC not treated with systemic therapies and healthy control (HC) subjects for comparison.

RESULTS

Twenty-eight patients were enrolled in the mRCC group (a mean age of 65.2 ± 7.5 years), 29 patients in the localized RCC group (63.6 ± 8.9 years), and 20 volunteers in the HC group (52.9 ± 9.6 years). At baseline, patients from all three groups had normal cardiac function as measured by left ventricular ejection fraction (LVEF), although patients with mRCC or localized RCC had significantly lower mean LVEF compared to HC (61.9%, 62.4%, and 68.1% respectively). Otherwise, there were no statistically significant changes in echocardiographic parameters or incidence of clinical heart failure from baseline to 6-months in patients with mRCC. Cardiac blood biomarkers including troponin I, brain natriuretic peptide, and galectin-3 remained stable over time.

CONCLUSION

Our findings suggest that contemporary treatment strategies of mRCC at this single institution are well tolerated without clinically meaningful overt declines in cardiac function over time. Further studies are warranted to include a larger number of patients to better assess the overall cardiovascular safety associated with contemporary treatments of mRCC.

Sunitinib resistance in renal cell carcinoma: From molecular mechanisms to predictive biomarkers

Currently, renal cell carcinoma (RCC) is the most prevalent type of kidney cancer. Targeted therapy has replaced radiation therapy and chemotherapy as the main treatment option for RCC due to the lack of significant efficacy with these conventional therapeutic regimens. Sunitinib, a drug used to treat gastrointestinal tumors and renal cell carcinoma, inhibits the tyrosine kinase activity of a number of receptor tyrosine kinases, including vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), c-Kit, rearranged during transfection (RET) and fms-related receptor tyrosine kinase 3 (Flt3). Although sunitinib has been shown to be efficacious in the treatment of patients with advanced RCC, a significant number of patients have primary resistance to sunitinib or acquired drug resistance within the 6-15 months of therapy. Thus, in order to develop more efficacious and long-lasting treatment strategies for patients with advanced RCC, it will be crucial to ascertain how to overcome sunitinib resistance that is produced by various drug resistance mechanisms. In this review, we discuss: 1) molecular mechanisms of sunitinib resistance; 2) strategies to overcome sunitinib resistance and 3) potential predictive biomarkers of sunitinib resistance.

New frontiers against sorafenib resistance in renal cell carcinoma: From molecular mechanisms to predictive biomarkers

Renal cell carcinoma (RCC) is a highly vascularized tumor and prone to distant metastasis. Sorafenib is the first targeted multikinase inhibitor and first-line chemical drug approved for RCC therapy. In fact, only a small number of RCC patients benefit significantly from sorafenib treatment, while the growing prevalence of sorafenib resistance has become a major obstacle for drug therapy effectivity of sorafenib. The molecular mechanisms of sorafenib resistance in RCC are not completely understood by now. Herein, we comprehensively summarize the underlying mechanisms of sorafenib resistance and molecular biomarkers for predicting sorafenib responsiveness. Moreover, we outline strategies suitable for overcoming sorafenib resistance and prospect potential approaches for identifying biomarkers associated with sorafenib resistance in RCC, which contributes to guide individualized and precision drug therapy.

Management of COVID-19 in cancer patients receiving cardiotoxic anti-cancer therapy. Future recommendations for cardio-oncology

Cardiotoxicity induced by anti-cancer treatment has become a significant threat as the number of cardiotoxic anti-cancer agents is growing. Cancer patients are at an increased risk of contracting coronavirus disease 2019 (COVID-19) because of immune suppression caused by anti-cancer drugs and/or supportive treatment. Deterioration in lung functions due to COVID-19 is responsible for many cardiac events. The presence of COVID-19 and some of its treatment modalities may increase the chance of cardiotoxicity development in cancer patients receiving potentially cardiotoxic agents. This review provides evidence-based information on the cardiotoxicity risk in cancer patients clinically diagnosed with COVID-19 who are receiving potentially cardiotoxic anti-cancer agents. Proposed strategies relating to the management of this patient cohorts are also discussed.

Outcome of third-line sunitinib after sequential therapy with cytokines and sorafenib in metastatic renal cell carcinoma

Third-line sunitinib is occasionally used for selected patients with metastatic renal cell carcinoma (mRCC). The aim of the present study was to evaluate the clinical significance of third-line sunitinib after failure of first-line cytokine therapy and second-line sorafenib in patients with clear-cell mRCC. A total of 14 consecutive patients with clear-cell mRCC treated with third-line sunitinib between December 2008 and February 2012 were enrolled in the present study. Disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and relative dose intensity (RDI) were compared with those of first-line (n=20) and second-line (n=14) sunitinib treatment. The DCR was 42.9%, the median PFS was 12.0 months, and the median OS was 20.0 months for third-line sunitinib; there were no statistically significant differences compared with first-line and second-line sunitinib. The mean RDI was significantly lower for third-line sunitinib compared with first- and second-line sunitinib (P=0.0003 and 0.0109, respectively). Therefore, third-line sunitinib is an effective treatment option for selected patients with mRCC, as optimized therapeutic efficacy was obtained with a relatively low dose of sunitinib.

Drug resistance in papillary RCC: from putative mechanisms to clinical practicalities

Papillary renal cell carcinoma (pRCC) is the second most common renal cell carcinoma (RCC) subtype and accounts for 10-15% of all RCCs. Despite clinical need, few pharmacogenomics studies in pRCC have been performed. Moreover, current research fails to adequately include pRCC laboratory models, such as the ACHN or Caki-2 pRCC cell lines. The molecular mechanisms involved in pRCC development and drug resistance are more diverse than in clear-cell RCC, in which inactivation of VHL occurs in the majority of tumours. Drug resistance to multiple therapies in pRCC occurs via genetic alteration (such as mutations resulting in abnormal receptor tyrosine kinase activation or RALBP1 inhibition), dysregulation of signalling pathways (such as GSK3β-EIF4EBP1, PI3K-AKT and the MAPK or interleukin signalling pathways), deregulation of cellular processes (such as resistance to apoptosis or epithelial-to-mesenchymal transition) and interactions between the cell and its environment (for example, through activation of matrix metalloproteinases). Improved understanding of resistance mechanisms will facilitate drug discovery and provide new effective therapies. Further studies on novel resistance biomarkers are needed to improve patient prognosis and stratification as well as drug development.

Sequential Treatment Based on Sunitinib and Sorafenib in Patients with Metastatic Renal Cell Carcinoma

Objectives: The aim of our study was to evaluate the outcome of alternative sequences of sunitinib followed by sorafenib versus sorafenib followed by sunitinib therapies in patients with metastatic renal cell carcinoma (mRCC).

Materials and Methods: This single-center study analyzed patients with mRCC on systemic therapy between January 2005 and August 2011. Patients were treated with the recommended first-line therapy (sunitinib, sorafenib, pazopanib, or immunotherapy) until progression or intolerable toxicity and afterward switched to another guideline-recommended systemic therapy. Only patients starting first-line therapy on either sorafenib or sunitinib and switching to the other of these drugs were included in this analysis.

Results: Out of 266 patients (females: 85, males: 181) with a median age of 57.1 years (30 - 76 years), 57 patients with a sequence of sunitinib and sorafenib were identified. First-line sorafenib therapy was followed by sunitinib (So-Su) in 32 patients; sunitinib was followed by sorafenib (Su-So) in 25 patients. Progression-free survival (PFS) for patients with first-line sorafenib was 11.6 months and was 8.7 months for sunitinib. Overall survival (OS) rates for Su-So was 118.8 months and 83.3 months with So-Su (p = 0.82). No new safety signals were detected.

Conclusion: None of the therapeutic first-line approaches was superior to the other. Sequencing tyrosine kinase inhibitor (TKI) therapy seems to be effective in mRCC and superior to single-line therapy. Further studies should focus on the efficacy of single treatment lines rather than treatment sequences to estimate more potent drugs based on PFS rather than overall survival (OS).

SWITCH II: Phase III randomized, sequential, open-label study to evaluate the efficacy and safety of sorafenib-pazopanib versus pazopanib-sorafenib in the treatment of advanced or metastatic renal cell carcinoma (AUO AN 33/11)

PURPOSE

This trial compared the sequential therapy with the multikinase inhibitor sorafenib (So) followed by pazopanib (Pa) or vice versa in advanced/metastatic renal cell carcinoma (mRCC) patients.

METHODS

This multicenter, randomized phase 3 study assessed the sequential use of So-Pa versus Pa-So in patients with mRCC without prior systemic therapy. Pts were randomized to So 2 × 400 mg/day followed by Pa 1 × 800 mg/day in case of progression or intolerable toxicity or vice versa. Primary endpoint was total PFS (tPFS), defined as time from randomization to progression, or death during second-line therapy. Key secondary endpoints included overall survival (OS), first-line PFS, disease control rate (DCR) and safety.

RESULTS

A total of 377 pts were randomized (So-Pa, n = 189; Pa-So, n = 188). Recruitment of a total 544 pts was calculated, but actual accrual rate turned out to be lower than expected. The primary endpoint median tPFS was 8.6 mo (95% CI 7.7-10.2) for So-Pa and 12.9 mo (95% CI 10.8-15.2) for Pa-So with a hazard ratio (HR) of 1.36 (upper limit of one-sided 95% CI 1.68), which exceeded a predefined HR <1.225 as a one-sided 95% confidence interval. Non-inferiority of So-Pa regarding tPFS was not met. Secondary endpoints displayed marked statistical differences in favor of Pa-So in first-line PFS and DCR but not for OS and 2nd-line PFS. Side effect profiles were consistent with known toxicities of the respective multikinase-inhibitor including diarrhea, fatigue, hand-foot skin reaction and hypertension.

CONCLUSIONS

Non-inferiority of the primary endpoint tPFS could not be demonstrated for So-Pa. The results for first-line PFS and DCR favored the Pa-So sequence.

TRIAL REGISTRATION

NCT01613846, www.clinicaltrials.gov.

Axitinib, cabozantinib, everolimus, nivolumab, sunitinib and best supportive care in previously treated renal cell carcinoma: a systematic review and economic evaluation

BACKGROUND

Several therapies have recently been approved for use in the NHS for pretreated advanced or metastatic renal cell carcinoma (amRCC), but there is a lack of comparative evidence to guide decisions between them.

OBJECTIVE

To evaluate the clinical effectiveness and cost-effectiveness of axitinib (Inlyta®, Pfizer Inc., NY, USA), cabozantinib (Cabometyx®, Ipsen, Slough, UK), everolimus (Afinitor®, Novartis, Basel, Switzerland), nivolumab (Opdivo®, Bristol-Myers Squibb, NY, USA), sunitinib (Sutent®, Pfizer, Inc., NY, USA) and best supportive care (BSC) for people with amRCC who were previously treated with vascular endothelial growth factor (VEGF)-targeted therapy.

DATA SOURCES

A systematic review and mixed-treatment comparison (MTC) of randomised controlled trials (RCTs) and non-RCTs. Primary outcomes were overall survival (OS) and progression-free survival (PFS). Secondary outcomes were objective response rates (ORRs), adverse events (AEs) and health-related quality of life (HRQoL). MEDLINE, EMBASE and The Cochrane Library were searched from inception to January and June 2016 for RCTs and non-RCTs, respectively. Two reviewers abstracted data and performed critical appraisals.

REVIEW METHODS

A fixed-effects MTC was conducted for OS, PFS [hazard ratios (HRs)] and ORR (odds ratios), and all were presented with 95% credible intervals (CrIs). The RCT data formed the primary analyses, with non-RCTs and studies rated as being at a high risk of bias included in sensitivity analyses (SAs). HRQoL and AE data were summarised narratively. A partitioned survival model with health states for pre progression, post progression and death was developed to perform a cost-utility analysis. Survival curves were fitted to the PFS and OS results from the MTC. A systematic review of HRQoL was undertaken to identify sources of health state utility values.

RESULTS

Four RCTs (n = 2618) and eight non-RCTs (n = 1526) were included. The results show that cabozantinib has longer PFS than everolimus (HR 0.51, 95% CrI 0.41 to 0.63) and both treatments are better than BSC. Both cabozantinib (HR 0.66, 95% CrI 0.53 to 0.82) and nivolumab (HR 0.73, 95% CrI 0.60 to 0.89) have longer OS than everolimus. SAs were consistent with the primary analyses. The economic analysis, using drug list prices, shows that everolimus may be more cost-effective than BSC with an incremental cost-effectiveness ratio (ICER) of £45,000 per quality-adjusted life-year (QALY), as it is likely to be considered an end-of-life treatment. Cabozantinib has an ICER of £126,000 per QALY compared with everolimus and is unlikely to be cost-effective. Nivolumab was dominated by cabozantinib (i.e. more costly and less effective) and axitinib was dominated by everolimus.

LIMITATIONS

Treatment comparisons were limited by the small number of RCTs. However, the key limitation of the analysis is the absence of the drug prices paid by the NHS, which was a limitation that could not be avoided owing to the confidentiality of discounts given to the NHS.

CONCLUSIONS

The RCT evidence suggests that cabozantinib is likely to be the most effective for PFS and OS, closely followed by nivolumab. All treatments appear to delay disease progression and prolong survival compared with BSC, although the results are heterogeneous. The economic analysis shows that at list price everolimus could be recommended as the other drugs are much more expensive with insufficient incremental benefit. The applicability of these findings to the NHS is somewhat limited because existing confidential patient access schemes could not be used in the analysis. Future work using the discounted prices at which these drugs are provided to the NHS would better inform estimates of their relative cost-effectiveness.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016042384.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Modern Systemic Therapy for Metastatic Renal Cell Carcinoma of the Clear Cell Type

In the last 30 years, there have been many advances in the treatment of metastatic renal cell carcinoma of the clear cell type. Renal cell carcinoma has long been understood to have a component of immune mediation and has been responsive to immune-based therapies; in addition to early cytokine therapy, newer checkpoint inhibition therapies have also demonstrated activity. Molecular characterization of the genome of clear cell renal cell carcinoma enabled identification of the roles of angiogenesis and hypoxic stress. This led to development of small-molecule tyrosine kinase inhibitors and inhibitors of mammalian target of rapamycin that have provided additional benefit to patients. Ongoing strategies of combinations of immune and antiangiogenic therapies may lead to further advancements.

Survival outcomes of double- and triple-sequential targeted therapy in patients with metastatic renal cell carcinoma: a retrospective comparison

Objective

To evaluate the progression-free survival (PFS) and overall survival (OS) in patients with metastatic renal cell carcinoma (mRCC) treated with double- and triple-sequence targeted therapy (TT) using tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin inhibitors (mTORi).

Materials and Methods

Records of 292 patients with mRCC, treated with TT between January 2005 and July 2015, were analyzed retrospectively. Kaplan-Meier and log-rank analyses were used to calculate and compare the total PFS (tPFS) and OS when patients underwent double- or triple-TT using TKIs or mTORi.

Results

Eighty-one (27.7%) patients who underwent second-line TT were enrolled; 30 (10.3%) of whom underwent third-line TT. The tPFS and OS of double-TT using TKI-mTORi (5.4 and 30 months, respectively) were significantly better compared with TKI-TKI (0.3 and 2 months) or mTORi-TKI (2 and 6 months) (p <0.001). For triple-TT, the tPFS and OS of TKI-mTORi-TKI (22.8 and 25 months, respectively) were significantly superior compared with those for TKI-TKI-mTORi (4 and 9 months) (p <0.05).

For patients with intermediate-risk according to the Heng or Memorial Sloan-Kettering Cancer Center risk models, TKI-mTORi was associated with a significantly longer tPFS and OS compared with TKI-TKI [expect for OS in the Heng group (p = 0.086)]. For the triple TT group, TKI-mTORi-TKI resulted in improved tPFS and OS compared with TKI-TKI-TKI or TKI-TKI-mTORi (p <0.05).

Conclusion

In patients with mRCC, sequential administration of TKI-mTORi led to a significantly superior tPFS compared with any other TT sequence. By contrast, OS did not differ significantly according to TT sequence.

Efficacy of sequential therapies with sorafenib-sunitinib versus sunitinib-sorafenib in metastatic renal cell carcinoma: A systematic review and meta-analysis

The most efficient sequence of targeted agents for metastatic renal cell carcinoma patients has yet to be identified. Whether the sequence of sorafenib and sunitinib really matters is controversial and not answered clearly until now. This meta-analysis aims to estimate the efficacy of receptor tyrosine kinase inhibitors sorafenib-sunitinib and sunitinib-sorafenib for metastatic renal cell carcinoma, on the outcome of first-line progression-free survival, second-line progression-free survival, total progression-free survival and overall survival.

We searched PubMed, Embase, Cochrane Library and ClinicalTrails.gov for eligible studies. Data were analyzed using random or fixed effects model depending on the heterogeneity of the eligible studies. Heterogeneity across studies were analyzed using Q and I2 statistics.

Of 902 identified studies, ten were qualified in our analysis (N = 1732 patients). Sorafenib-sunitinib yielded no statistically significant benefit in first-line progression-free survival (fixed effects; HR = 0.95; 95%CI 0.75-1.21; p = 0.702), total progression-free survival (random effects; HR = 0.92; 95%CI 0.71-1.19; p = 0.531) and overall survival (fixed effects; HR = 0.89; 95%CI 0.72-1.09; p = 0.257), compared with sunitinib-sorafenib. Second-line progression-free survival was longer for sorafenib-sunitinib than sunitinib-sorafenib (fixed effects; HR = 0.55; 95%CI 0.44-0.68; p = 0.000).

Sequential therapies with sorafenib and sunitinib is well tolerated and efficient in mRCC. However, there are no evidence supported that sorafenib–sunitinib has the superiority to sunitinib-sorafenib in sequence. The ideal sequence of targeted agents requires further elucidation.

Sunitinib in the treatment of renal cell carcinoma: an update on recent evidence

Sunitinib is a multitarget tyrosine kinase inhibitor endowed mainly by antiangiogenic effects, although an indirect inhibitory effect on tumor growth and, more recently, a complex activity on antitumor immune response has been described. From approval by the US Food and Drug Administration (FDA) in January 2006, sunitinib represents a key molecule in the treatment of metastatic renal cell carcinoma (mRCC) due to the peculiar molecular pathogenesis of this neoplasm. Over the past 10 years, clinical trials and real-world experiences helped clinicians to understand how, when and for how long to use sunitinib. Although a huge amount of data evidenced the relationship existing between sunitinib dose intensity and improved clinical outcome, the management of sunitinib-induced adverse events is often complex; thus, alternative schedules have been proposed over time which allow increased tolerability, without decreased daily sunitinib exposure, leading to improved clinical outcomes. To date, combinations of sunitinib with other approved targeted agents did not demonstrate any significant benefit over its single-agent use, mainly due to tolerability issues. Sunitinib has also been tested in the adjuvant setting, within the ASSURE and S-TRAC trials, with opposite results; indeed, equivocal risk-stratification criteria, as well as immature overall survival (OS) data prevent any definitive conclusion on this important issue. Despite being on the market for a long time, sunitinib still plays a role as the 'comparator arm' of a number of trials in the field of mRCC. Combinations with immune checkpoint inhibitors and vaccines look promising; once again, sunitinib can help us to optimize mRCC management.

Long-Term Response to Sunitinib Treatment in Metastatic Renal Cell Carcinoma: A Pooled Analysis of Clinical Trials

BACKGROUND

We characterized clinical outcomes of patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib who were long-term responders (LTRs), defined as patients having progression-free survival (PFS) > 18 months.

PATIENTS AND METHODS

A retrospective analysis of data from 5714 patients with mRCC treated with sunitinib in 8 phase II/III clinical trials and the expanded access program. Duration on-study and objective response rate (ORR) were compared between LTRs and patients with PFS ≤ 18 months ("others"). PFS and overall survival (OS) were summarized using Kaplan-Meier methodology.

RESULTS

Overall, 898 (15.7%) patients achieved a long-term response and 4816 (84.3%) patients did not achieve long-term response. The median (range) duration on-study was 28.6 (16.8-70.7) months in LTRs and 5.5 (0-68.8) months in others. ORR was 51% in LTRs versus 14% in others (P < .0001). Median PFS in LTRs was 32.11 months and median OS was not reached. LTRs had higher percentage of early tumor shrinkage ≥ 10% at the first scan (67.1% vs. 51.2%; P = .0018) and greater median maximum on-study tumor shrinkage from baseline (-56.9 vs. -27.1; P < .0001) versus others. White race, Eastern Cooperative Oncology Group performance status 0, time from diagnosis to treatment ≥ 1 year, clear cell histology, no liver metastasis, lactate dehydrogenase ≤ 1.5 upper limit of normal (ULN), corrected calcium ≤ 10 mg/dL, hemoglobin greater than the lower limit of normal, platelets less than or equal to ULN, body mass index ≥ 25 kg/m2, and low neutrophil-to-lymphocyte ratio were associated with LTR.

CONCLUSION

A subset of patients with mRCC treated with sunitinib achieved long-term response. LTRs had improved ORR, PFS, and OS.

Sunitinib in the treatment of metastatic renal cell carcinoma

Sunitinib is an oral multi-targeted tyrosine kinase inhibitor (TKI) that targets various receptors, including vascular endothelial growth factor receptors (VEGFRs). Sunitinib received approval in 2006 and became a standard treatment option in the first-line treatment of metastatic renal cell cancer (mRCC) after a phase III trial showed superiority compared with interferon alpha (IFN-α). Sunitinib has also shown activity in second-line treatment in several trials. Most of the combination trials with sunitinib with various agents have led to considerable toxicity without improving efficacy. Sunitinib alone causes significant side effects and has a distinct profile with diarrhoea, hypertension, skin effects hypothyroidism, fatigue and nausea of special interest. The recommended dose of sunitinib in mRCC is 50 mg orally daily for 4 weeks, followed by 2 weeks off treatment (4/2 schedule). An alternative 2 weeks on, 1 week off schedule (2/1 schedule) seems to be of similar efficacy and better tolerability and could be more widely used in the future. An intermittent treatment strategy with a stop in remission and re-induction after progression showed efficacy in smaller trials and is currently being evaluated in a phase III trial. Direct comparison of sunitinib with pazopanib in first-line treatment showed a similar efficacy for both TKIs with a distinct toxicity profile. Data from two phase II trials showed that sunitinib has also activity in non-clear cell cancer and is an option due to a lack of better alternatives. Currently, after immune checkpoint inhibitors have shown very promising results in the second-line treatment of RCC, they are being tested in a number of phase III trials in the first-line setting. The future will show the position of sunitinib in the first-line treatment of RCC in the era of the immune checkpoint inhibitors.

Axitinib in sequential therapy in metastatic renal cell carcinoma

Efficacy of new molecularly targeted drugs in the treatment of renal cell carcinoma (RCC), confirmed in clinical studies in relation to survival and prolongation of time to progression, has became a big chance for patients with metastatic renal cell cancer. Axitinib is a potent and selective receptor tyrosine kinase for vascular endothelial growth factor (VEGFR-1, -2, -3), platelet-derived growth factor β (PDGRF-β) and c-KIT. This is a case report of a 57-year old female patient with a history of left nephrectomy due to clear cell renal cell carcinoma. The patient had received three prior systemic treatments (interferon - sorafenib - everolimus). After consecutive progression the patient was qualified to 4^th line therapy - axitinib at a dose of 5 mg twice daily. Partial response to treatment was achieved. After 6 months therapy was stopped due to the disease progression. The total time to progression was 37.5 months. The total survival time from the disease diagnosis was 45 months. Based on literature date and own experience we showed that sequential treatment RCC is associated with improved survival. In summary, axitinib may be an effective drug after failure of tyrosine-kinase inhibitor (TKI) therapy in previous lines of therapy.

Efficacy and toxicity of sunitinib in metastatic renal cell carcinoma patients in Egypt

BACKGROUND

To evaluate our results in terms of response, survival and toxicity profile of sunitinib among Egyptian patients with metastatic renal cell carcinoma.

MATERIALS AND METHODS

Between January 2010 and December 2013, 44 patients with metastatic renal cell carcinoma who received sunitinib at an oncology center of Cairo university hospitals were enrolled in this retrospective analysis.

RESULTS

The median age of the patients was 53 years, 22 (50%) having localized disease at presentation ,while the remaining half of the patients presented with metastasis. At a median follow up of 19 months, 9 (21%) patients achieved partial remission, while disease was reported stable in 20 cases (45%) and progressive in 7 (16%), 4 (9%) being lost to follow up, and 4 (9%) had discontinued therapy due to toxicity. The median overall survival was 23 months (95%CI 15.2 - 30.9), while progression free survival was 12 months (95%CI 11.6 - 12.3). The most commonly reported non hematological grade 3 adverse events included mucositis (15.9%), hand-foot syndrome (13.6%), and fatigue (9%), while the predominant grade 3 or 4 laboratory abnormalities were neutropenia (6.8%), followed by anemia in 4.5% of patients.

CONCLUSIONS

Our efficacy data were comparable to the published literature in terms of progression free survival and overall survival , while toxicity profile is different from Asian and western countries. However, sunitinib adverse events were manageable and tolerable in most of our Egyptian patients.

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.

Retrospective Analysis of the Efficacy and Safety of Sorafenib in Chinese Patients With Metastatic Renal Cell Carcinoma and Prognostic Factors Related to Overall Survival

Sorafenib has been recommended as first- or second-line treatment for metastatic renal cell carcinoma (mRCC) by several guidelines. The objective of this study is to evaluate the efficacy of sorafenib monotherapy in Chinese patients with mRCC and determine the prognostic clinicopathologic factors associated with survival in these patients.This is a single-arm retrospective study conducted in 2 tertiary medical centers; 140 mRCC patients were enrolled between January 2007 and June 2014. Sorafenib was administered at a dose of 400 mg twice daily, and continued until disease progression, at which point the dose was increased to 600 or 800 mg twice daily, or the onset of an intolerable adverse drug event (ADE) that required dose reduction or temporary suspension of treatment.The primary endpoint was overall survival (OS), and the secondary endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety.The median follow-up time was 32 months. The median OS and PFS were 24 months (range, 3-88 months) and 16 months (range, 0-88 months), respectively. Patients with clear cell carcinoma had a greater OS (P=0.001) whereas sarcomatoid differentiation (P=0.045) and disease progression (P=0.010) negatively impacted OS; time from kidney surgery or biopsy to initiation of sorafenib treatment was associated with PFS (P=0.027). Efficacy analysis revealed that 3 (2.1%) patients achieved complete responses, 28 (20.0%) patients experienced partial responses, 88 (62.9%) patients had stable disease, and 21 (15.0%) patients developed progressive disease. Moreover, the ORR was 22.1%, and the DCR was 85.0%. Most ADEs were classified as grades 1 or 2 with only 14 (10.0%) patients experiencing a severe ADE (grade 3).Sorafenib monotherapy can achieve promising OS and PFS for Chinese patients with mRCC, especially in those with clear cell carcinoma, with manageable adverse events.

SWITCH: A Randomised, Sequential, Open-label Study to Evaluate the Efficacy and Safety of Sorafenib-sunitinib Versus Sunitinib-sorafenib in the Treatment of Metastatic Renal Cell Cancer

BACKGROUND

Understanding how to sequence targeted therapies for metastatic renal cell carcinoma (mRCC) is important for maximisation of clinical benefit.

OBJECTIVES

To prospectively evaluate sequential use of the multikinase inhibitors sorafenib followed by sunitinib (So-Su) versus sunitinib followed by sorafenib (Su-So) in patients with mRCC.

DESIGN, SETTING, AND PARTICIPANTS

The multicentre, randomised, open-label, phase 3 SWITCH study assessed So-Su versus Su-So in patients with mRCC without prior systemic therapy, and stratified by Memorial Sloan Kettering Cancer Center risk score (favourable or intermediate).

INTERVENTION

Patients were randomised to sorafenib 400mg twice daily followed, on progression or intolerable toxicity, by sunitinib 50mg once daily (4 wk on, 2 wk off) (So-Su), or vice versa (Su-So).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was improvement in progression-free survival (PFS) with So-Su versus Su-So, assessed from randomisation to progression or death during second-line therapy. Secondary endpoints included overall survival (OS) and safety.

RESULTS AND LIMITATIONS

In total, 365 patients were randomised (So-Su, n=182; Su-So, n=183). There was no significant difference in total PFS between So-Su and Su-So (median 12.5 vs 14.9 mo; hazard ratio [HR] 1.01; 90% confidence interval [CI] 0.81-1.27; p=0.5 for superiority). OS was similar for So-Su and Su-So (median 31.5 and 30.2 mo; HR 1.00, 90% CI 0.77-1.30; p=0.5 for superiority). More So-Su patients than Su-So patients reached protocol-defined second-line therapy (57% vs 42%). Overall, adverse event rates were generally similar between the treatment arms. The most frequent any-grade treatment-emergent first-line adverse events were diarrhoea (54%) and hand-foot skin reaction (39%) for sorafenib; and diarrhoea (40%) and fatigue (40%) for sunitinib.

CONCLUSIONS

Total PFS was not superior with So-Su versus Su-So. These results demonstrate that sorafenib followed by sunitinib and vice versa provide similar clinical benefit in mRCC.

PATIENT SUMMARY

We investigated if total progression-free survival (PFS) is improved in patients with advanced/metastatic kidney cancer who are treated with sorafenib and then with sunitinib (So-Su), compared with sunitinib and then sorafenib (Su-So). We found that total PFS was not improved with So-Su compared with Su-So, but both treatment options were similarly effective in patients with advanced/metastatic kidney cancer.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT00732914, www.clinicaltrials.gov.

Management of metastatic renal cell carcinoma progressed after sunitinib or another antiangiogenic treatment

Prognosis of metastatic renal cell carcinoma (mRCC) has markedly improved in the recent years. Several factors such as precocious diagnosis, better supportive care, and an increased number of targeted therapies are responsible for this progress. From 2006 to date, 7 drugs have been approved for treatment of mRCC, and among these only 2 are recommended for the second line of therapy with grade 1 evidence. Tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin (mTOR) inhibitors are the strategies with more evidence, but no comparative studies are available and what is the best second line remains an open issue. Herein, we review the available evidence on the second-line treatment focusing mainly on prospective studies. We identify a special population of patients in whom more evidence is available, and we propose a possible strategy for the management of progressed mRCC and for primary resistant lesions as well as for patients who need a rapid response in lesions. In the majority of patients, several factors should be considered: toxicity reported during first-line therapy, performance status, the absence of correlation between the length of first-line therapy and the probability to respond to second-line therapy, and the lack of comparative trials between mTOR inhibitors and TKI. When an mTOR inhibitor is selected, everolimus must be preferred, although in the RECORD1 trial only the increase in progression-free survival has been reported and the increase in terms of overall survival has not been reached. When another TKI is the choice, there are no strong pieces of evidence that favor the use of a defined molecule. In every case, we recommend to start the selected targeted agents at standard dosage and to pursue therapy as long as possible because the control of disease should be the primary endpoint for the management of mRCC.

Prognostic value of hematologic parameters in patients with metastatic renal cell carcinoma using tyrosine kinase inhibitors

BACKGROUND

The prognostic significance of the neutrophil-to-lymphocyte ratio for progression free survival in patients with metastatic renal cell carcinoma is unclear.

MATERIALS AND METHODS

We retrospectively reviewed 45 patients diagnosed with metastatic RCC previously treated with tyrosine kinase inhibitors from two centers, Akdeniz University Hospital and Afyon Kocatepe University. The prognostic value of the pretreatment neutrophil- tolymphocyte ratio, and other clinical and laboratory parameters were assessed by univariate and multivariate analysis.

RESULTS

Median progression free survival (PFS) was 13.9 months [95% CI for HR (6.88-20.91)] and overall survival figure of 16.6 months [95% CI for HR (7.23-26.03)] Univariate analysis revealed that PFS was significantly affected by hemoglobin level [p=0.013 (95% CI for HR (0.71-0.96))], eosinophil count [p=0.031 (95% CI for HR (0.20-0.92))], ratio of neutrophil lymphocytes (NLR) [p=0.007 (95% CI for HR (1.47-11.74))] and calcium level [p=0.006 (95% CI for HR (0.15-0.73))]. However, only NLR [p=0.031 (95% CI for HR (1.15- 18.1))] and calcium levels [p=0.018 (95% CI for HR (0.20-18.1))] retained significance with multivariate analysis. Median PFS was 23.9 vs 8.6 months in patients with NLR ≤ 2 vs NLR >2 (Log rank; p= 0.040).

CONCLUSIONS

This study showed that increased pretreatment NLR is an independent prognostic factor for patients with metastatic RCC using tyrosine kinase inhibitors.

Molecular analysis of sunitinib resistant renal cell carcinoma cells after sequential treatment with RAD001 (everolimus) or sorafenib

Sequential application of target drugs is standard procedure after renal cell carcinoma (RCC) patients develop resistance. To optimize the sequence, antitumour effects of the mTOR inhibitor RAD001 or the tyrosine kinase inhibitor (TKI) sorafenib on RCC cells with acquired resistance to the TKI sunitinib was evaluated. RCC cells were exposed to 1 μM sunitinib for 24 hrs (as control) and for 8 weeks (to induce resistance) and then switched to RAD001 (5 nM) or sorafenib (5 μM) for a further 8 weeks. Tumour cell growth, cell cycle progression, cell cycle regulating proteins and intracellular signalling were then investigated. Short-term application of sunitinib (24 hrs) induced cell growth blockade with accumulation in the G2/M phase. RCC cells became resistant to sunitinib after 8 weeks, demonstrated by accelerated cell growth along with enhanced cdk1, cdk2, loss of p27, activation of Akt, Rictor and Raptor. Switching to sorafenib only slightly reduced growth of the sunitinib resistant RCC cells and molecular analysis indicated distinct cross-resistance. In contrast, full response was achieved when the cancer cells were treated with RAD001. p19 and p27 strongly increased, phosphorylated Akt, Rictor and Raptor decreased and the tumour cells accumulated in G0/G1. It is concluded that an mTOR-inhibitor for second-line therapy could be the strategy of choice after first-line sunitinib failure.

Optimal first-line and second-line treatments for metastatic renal cell carcinoma: current evidence

Since 2005, an abundance of targeted agents has been approved for the treatment of metastatic renal cell carcinoma (mRCC), without any specification as to what may be the most optimal first-line and second-line sequence. Hence, our objective was to critically examine the evidence supporting the use of first-line and second-line agents in the management of mRCC. Our review suggests that in first line, sunitinib and pazopanib represent treatment options for patients with favorable or intermediate-risk features and clear cell histology. Unfortunately, the Phase III trial cannot conclusively prove the noninferiority of pazopanib relative to sunitinib. Hence, the use of sunitinib as first-line standard of care remains justified. Pazopanib represents an option for specific patients in whom sunitinib might not be tolerated. In patients with poor-risk features, temsirolimus represents the only option supported with level 1 evidence. Less optimal alternatives include sunitinib and bevacizumab combined with interferon, based on the minimal inclusion of poor-risk patients in pivotal Phase III studies of these two molecules. In patients with non-clear cell mRCC, the use of temsirolimus is supported by Phase III data, unlike for any other molecule. In second line, the options consist of everolimus and axitinib. However, the axitinib data are substantially more robust given the inclusion of more patients considered as true second-line, and validly justify the choice of axitinib over everolimus. Nonetheless, the Phase III trial of everolimus may be considered as level 1 evidence for use as third-line or subsequent lines of therapy.

Sunitinib re-challenge in advanced renal-cell carcinoma

Despite offering significant clinical benefits in advanced renal-cell carcinoma (RCC), the effectiveness of targeted therapies eventually declines with the development of resistance. Defining optimal sequences of therapy is therefore the focus of much current research. There is also evidence that treatment 're-challenge' may be an effective strategy in some patients. We review evidence to evaluate whether sunitinib may have value as re-challenge therapy in patients who have progressed on prior targeted therapy with sunitinib and/or an alternative tyrosine kinase inhibitor or mammalian target of rapamycin inhibitor. Re-challenge with sunitinib appears to be of clinical benefit, thus representing a feasible therapeutic option for patients with advanced RCC who are refractory to other treatments and are able to receive further therapy. These observations support hypotheses that resistance to targeted agents is transient and can be at least partially reversed by re-introduction of the same agent after a treatment break. Median progression-free survival durations appear to be shorter and response rates lower on re-challenge than following initial treatment, although a wider interval between treatments appears to increase response to sunitinib re-challenge.

Randomized phase II open-label study of mFOLFOX6 in combination with linifanib or bevacizumab for metastatic colorectal cancer

BACKGROUND

Although CRC is the third most commonly diagnosed cancer in the United States, second-line CRC treatment is limited. In this trial we examined the efficacy and safety of linifanib, an oral, potent, selective tyrosine kinase inhibitor of vascular endothelial growth factor and platelet-derived growth factor receptor families, with mFOLFOX6, compared with bevacizumab and mFOLFOX6, in previously treated metastatic CRC.

PATIENTS AND METHODS

One hundred forty-eight patients with advanced CRC previously treated with fluoropyrimidine or irinotecan received bevacizumab (10 mg/kg, intravenous), low-dose linifanib (7.5 mg), or high-dose linifanib (12.5 mg), with mFOLFOX6. The primary end point was progression-free survival (PFS). Secondary objectives included overall survival (OS), objective response rate (ORR), and safety.

RESULTS

No statistically significant differences in PFS occurred between bevacizumab and linifanib doses (low, hazard ratio [HR], 1.453 [95% confidence interval [CI], 0.830-2.539]; high, HR, 1.257 [95% CI, 0.672-2.351]). Median OS values were similar for bevacizumab and high-dose linifanib (bevacizumab, 16.5 months [95% CI, 13.0-not available]; high-dose linifanib, 16.4 months [95% CI, 11.9-21.7]; low-dose linifanib, 12.0 months [95% CI, 10.1-13.0]). ORRs were similar (bevacizumab, 34.7% [95% CI, 21.7-49.6]; low-dose linifanib, 24.0% [95% CI, 13.1-38.2]; high-dose linifanib, 22.4% [95% CI, 11.8-36.6]). Median cycles of 5-fluorouracil were reduced in the linifanib arms, versus the bevacizumab arm. Grade 3/4 adverse event occurrences were more frequent with linifanib. Palmar-plantar erythrodysesthesia, hypothyroidism, and thrombocytopenia were more common with high-dose linifanib than bevacizumab.

CONCLUSION

Combining linifanib with mFOLFOX6 as a second-line treatment for metastatic CRC did not improve PFS, radiographic findings, or duration of response versus bevacizumab and mFOLFOX6.

Role of salvage targeted therapy in differentiated thyroid cancer patients who failed first-line sorafenib

CONTEXT

Sorafenib, a tyrosine kinase inhibitor, is a common first-line therapy for advanced differentiated thyroid cancer (DTC). However, responses are not durable and drug toxicity remains a problem.

OBJECTIVE

The objective of the study was to determine the efficacy of salvage therapy after first-line sorafenib failure.

DESIGN

This was a retrospective review at M. D. Anderson Cancer Center from January 2005 to May 2013.

PATIENTS

The study included patients with metastatic DTC who received salvage therapy after their initial sorafenib failure (group 2). PATIENTS who received first-line sorafenib only (group 1) were evaluated for comparison of overall survival (OS).

OUTCOME MEASURES

Progression-free survival, best response, and median OS were measured.

RESULTS

Sixty-four patients with metastatic, radioactive iodine refractory DTC were included; 35 were in group 1 and 25 were in group 2, and the groups were well balanced. Median OS of all 64 patients receiving first line sorafenib was 37 months; median OS was significantly longer with salvage therapy compared with sorafenib alone (58 vs 28 months, P = .013). In group 2, 17 patients were evaluable for best response, although two patients had toxicity with sorafenib, which was discontinued before restaging. Best responses with first-line sorafenib were partial response in 2 of 15 (13%), stable disease in 10 of 15 (67%), and progressive disease in 3 of 15 (20%) patients. With salvage therapy, partial responses were seen in 7 of 17 (41%) and stable disease in 10 of 17 (59%) patients. Median progression-free survival was 7.4 months with first-line sorafenib and 11.4 months with salvage therapy. Salvage therapy included sunitinib (n = 4), pazopanib (n = 3), cabozantinib (n = 4), lenvatinib (n = 3), and vemurafenib (n = 3).

CONCLUSIONS

Other targeted agents are effective salvage treatments after sorafenib failure, despite similar mechanisms of action, and should be offered to patients who are able to receive salvage therapy.

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.

Controversies in renal cell carcinoma: treatment choice after progression on vascular endothelial growth factor-targeted therapy

The mammalian target of rapamycin inhibitor (mTORI) everolimus and the tyrosine kinase inhibitor (TKI) axitinib are the only two post-first-line treatment options for metastatic renal cell carcinoma (mRCC) licensed at present. Extrapolation of robust phase III studies suggests that median progression-free survival (PFS) is similar between agents. This presents a dilemma for the physician planning treatment for their patients with mRCC: should they be treated with a TKI-mTORI or a TKI-TKI sequence? The lack of direct comparison between axitinib and everolimus leaves the clinician without clear guidance on the optimal choice in second-line therapy. In phase III studies, both post first-line everolimus and axitinib have been shown to delay disease progression; however, cumulative toxicity with sequential use of TKIs may result in more treatment interruptions or dose reductions or increased likelihood of adverse events. While everolimus exerts a tolerability advantage, axitinib is associated with higher response rate and a similar PFS benefit. Proven superiority cannot be used to guide treatment sequence selection in mRCC. Instead, therapeutic planning requires us to take a long-term view of our patient's treatment that includes quality of life and a balance between symptom control, adverse event management and avoidance of unnecessary drug interruptions or dose reductions. In the absence of curative therapies, sustaining a patient's quality of life is a major goal throughout the course of treatment and choosing a second-line agent that is able to adequately achieve this by limiting adverse events should be a priority.

Management of metastatic renal cell carcinoma patients with poor-risk features: current status and future perspectives

With seven agents approved for renal cell carcinoma within the past few years, there has undoubtedly been progress in treating this disease. However, patients with poor-risk features remain a challenging and difficult-to-treat population, with the mTOR inhibitor, temsirolimus, the only agent approved in the first-line setting. Phase III trial data are still lacking VEGF-pathway inhibitors in patients with poor prognostic features. Poor-risk patients need to be considered as a heterogeneous population. Further understanding of biomarkers can lead to a better selection of patients who may benefit the most from treatment and improvements in prognosis. The presence of poor Karnofsky scores and liver or CNS disease may affect the outcome of these patients much more than other identified factors. This consideration may provide the rationale to further stratify poor-risk patients further subgroups destined to receive either cure or palliation.

Recombinant interleukin-21 plus sorafenib for metastatic renal cell carcinoma: a phase 1/2 study

Background

Despite the positive impact of targeted therapies on metastatic renal cell carcinoma (mRCC), durable responses are infrequent and an unmet need exists for novel therapies with distinct mechanisms of action. We investigated the combination of recombinant Interleukin 21 (IL-21), a cytokine with unique immunostimulatory properties, plus sorafenib, a VEGFR tyrosine kinase inhibitor.

Methods

In this phase 1/2 study, 52 mRCC patients received outpatient treatment with oral sorafenib 400 mg twice daily plus intravenous IL-21 (10–50 mcg/kg) on days 1–5 and 15–19 of each 7-week treatment course. The safety, antitumor activity, pharmacokinetic and pharmacodynamic effects of the combination were evaluated.

Results

In phase 1 (n = 19), the maximum tolerated dose for IL-21 with the standard dose of sorafenib was determined to be 30 mcg/kg/day; grade 3 skin rash was the only dose-limiting toxicity. In phase 2, 33 previously-treated patients tolerated the combination therapy well with appropriate dose reductions; toxicities were mostly grade 1 or 2. The objective response rate was 21% and disease control rate was 82%. Two patients have durable responses that are ongoing, despite cessation of both IL-21 and sorafenib, at 41+ and 30+ months, respectively. The median progression-free survival in phase 2 was 5.6 months. The pharmacokinetic and pharmacodynamic properties of IL-21 appeared to be preserved in the presence of sorafenib.

Conclusion

IL-21 plus sorafenib has antitumor activity and acceptable safety in previously treated mRCC patients. IL-21 may represent a suitable immunotherapy in further exploration of combination strategies in mRCC.

Trial registration

ClinicalTrials.gov Identifier: NCT00389285

Pazopanib after sunitinib failure in patients with metastatic renal cell carcinoma

BACKGROUND

Sunitinib is a standard agent for the treatment of metastatic renal cell carcinoma (mRCC). The objective of the study was to evaluate efficacy and safety of pazopanib in the treatment of patients whose mRCC either progressed on sunitinib or who discontinued sunitinib due to adverse effects.

MATERIAL AND METHODS

Thirty-one consecutive mRCC patients who received pazopanib after sunitinib failure were included in this retrospective single center study. Pazopanib was continued until disease progression or intolerance. Treatment response was evaluated every 8-12 weeks according to the RECIST criteria. Adverse events were recorded according to the Common Terminology Criteria for Adverse Events.

RESULTS

Six patients (19%, 95% CI 12-26%) achieved partial response with pazopanib, 18 (58%) had stable disease, and seven (23%) progressive disease as their best response. Of the 14 patients who received pazopanib as their second-line therapy, six (43%) responded as compared with no responses among 17 patients treated in a later line (p = 0.004). The median progression-free survival time was 7.4 months after starting pazopanib (range, 0.9-15.6 months). Patients who received pazopanib as second-line treatment had median progression-free survival of 11.0 months as compared with 3.8 months among those who received pazopanib in a later line (p = 0.031). Only one (3%) patient discontinued pazopanib due to an adverse event. The most commonly recorded adverse events were anemia, thrombocytopenia, diarrhea, fatigue, and elevation of serum creatinine concentration. Six (19%) patients had one or more grade 3 or 4 adverse events recorded.

CONCLUSION

Pazopanib has clinical activity in mRCC as second-line agent after sunitinib failure suggesting lack of complete cross-resistance. Pazopanib was associated with acceptable toxicity, and may be considered as an option after sunitinib failure.

Protein kinase inhibitors in renal cell carcinoma

INTRODUCTION

Metastatic Renal Cell Carcinoma (mRCC) was historically treated with cytokine therapy with a poor outcome. In the last decade, new therapies targeting vascular endothelial growth factor (VEGF) or the mammalian target of rapamycin (m-TOR) pathways demonstrated efficacy in mRCC. Protein kinase inhibitors as well as monoclonal antibodies targeting these pathways have become the standard treatment of renal cell carcinoma (RCC) in the first-line setting and beyond.

AREAS COVERED

This review describes the various Phase III trials concerning protein kinase inhibitors including anti-angiogenic tyrosine kinase inhibitors (TKIs) and m-TOR serine/threonine kinase inhibitors, which have demonstrated a benefit in the treatment of mRCC. It focuses on efficacy, safety and management.

EXPERT OPINION

VEGF TKI and m-TOR inhibitors have significantly improved the outcome of mRCC and offer a gain in survival by sequential treatments for the majority of patients. But they induce a particular toxicity profile. An adequate management of each drug and its sequence in treatment is essential to optimise the outcome and preserve the quality of life (QoL) of patients with mRCC. In forthcoming years, pending results should indicate whether VEGF TKI are of interest in an adjuvant setting and if new drugs targeting will challenge the current standard guidelines in the metastatic setting.

Clinical efficacy of targeted biologic agents as second-line therapy of advanced thyroid cancer

Targeted biologic agents showed clinically meaningful efficacy as front-line therapy for advanced radioiodine-refractory and medullary thyroid cancer. The clinical benefit of these agents beyond the front line has yet to be established.

METHODS

We assessed the clinical benefit of targeted agents in patients with advanced differentiated and medullary thyroid cancer treated at a single academic cancer center. We determined efficacy and compared front-line and second-line benefit using biochemical and anatomic response, time to treatment failure, and progression-free survival (PFS). Statistical differences were assessed by t test and chi-square test. Survival curves were generated by the Kaplan-Meier method. Differences in survival were assessed using the log-rank test, and a p value <.05 was considered significant.

RESULTS

We identified 39 patients with advanced differentiated and medullary thyroid cancer treated with targeted biologic agents. Median age was 56.3 years. Overall, 25 men and 14 women participated. Histology showed 23% medullary and 77% differentiated cancer. Nineteen patients progressed on front-line therapy and subsequently received second-line therapy. Targeted agents conferred clinically meaningful benefit in the second-line setting in terms of biochemical response (13.3%), clinical benefit (83.3%), median time to treatment failure (4.0 months; 95% confidence interval: 2.6-8.2), and median PFS (4.6 months; 95% confidence interval: 3.2-8.2). Second-line benefit (median PFS) was more modest in comparison to the front-line setting in both genders (women: 3 months vs. 12.2 months; men: 6 months vs. 19.7 months), in differentiated cancers (4.1 months vs. 15.7 months), and with vascular targeting agents (4.4 months vs. 20.1 months).

CONCLUSION

Patients with advanced thyroid cancer derived meaningful clinical benefit from additional therapy with a biologic agent following disease progression on front-line targeted therapy.

Outcomes of patients with metastatic clear-cell renal cell carcinoma treated with pazopanib after disease progression with other targeted therapies

AIM

The multi-tyrosine kinase inhibitor pazopanib prolongs progression-free survival (PFS) versus placebo in treatment-naive and cytokine-refractory metastatic clear-cell renal cell carcinoma (ccRCC). Outcomes and safety data with pazopanib after targeted therapy (TT) are limited.

METHODS

We retrospectively evaluated records of consecutive patients with metastatic ccRCC who had progressive disease (PD) after TT and received pazopanib from November 2009 through November 2011. Tumour response was assessed by a blinded radiologist using Response Evaluation Criteria In Solid Tumours (RECIST). PFS and overall survival (OS) were estimated by Kaplan-Meier methods.

RESULTS

Ninety-three patients were identified. Median number of prior TTs was 2 (range, 1-5). There were 68 events (PD or death). Among 85 evaluable patients, 13 (15%) had a partial response. Median PFS was 6.5 months (95% CI: 4.5-9.7); median OS was 18.1 months (95% CI: 10.26-NA). Common adverse events (AEs) included fatigue (44%), elevated transaminases (35%), diarrhoea (30%), hypothyroidism (18%), nausea/vomiting (17%), anorexia (14%) and hypertension exacerbation (14%); 91% of AEs were grade 1/2. Eleven patients (12%) discontinued therapy due to AEs. There were no treatment-related deaths.

CONCLUDING STATEMENT

Pazopanib demonstrated efficacy in patients with metastatic ccRCC after PD with other TTs. Toxicity overall was mild/moderate and manageable.

Treatment and overall survival in renal cell carcinoma: a Swedish population-based study (2000-2008)

BACKGROUND

This retrospective register study assessed overall survival (OS) and influential factors on OS in Swedish renal cell carcinoma (RCC) patients.

METHODS

Using three merged national health registers, Cox proportional-hazards analysis was conducted and, in three models, it was used to assess the impact of cytokine (interferon-α and tyrosine kinase inhibitor (TKI; sunitinib or sorafenib) treatment on OS in metastatic (m)RCC.

RESULTS

From 2000 to 2008, 8009 patients were diagnosed with RCC and 2753 with mRCC (2002-2008). Median OS in RCC patients diagnosed from 2006 to 2008 compared with 2000-2005 was not reached vs 47.9 months (P<0.001), and in mRCC patients diagnosed from 2006 to 2008 compared with 2002-2005, was 12.4 vs 9.6 months, respectively (P=0.004). Factors associated with significantly improved OS in RCC were female gender, lower age, and previous nephrectomy, and, in mRCC female gender, previous nephrectomy, and any TKI prescription (Model 1: median-adjusted OS, 19.4 months (TKI patients) vs 9.7 months (non-TKI patients); hazard ratio, 0.621; P<0.001).

CONCLUSION

OS was improved in Swedish patients diagnosed with RCC and mRCC in the period 2006-2008 compared with 2000-2005 (RCC) and 2002-2005 (mRCC). Although multifactorial in origin, results suggest that increased nephrectomy rates and the use of TKIs contributed to the improvement seen in mRCC patients.

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.

Sequential therapy in metastatic renal cell carcinoma: pre-clinical and clinical rationale for selecting a second- or subsequent-line therapy with a different mechanism of action

Few types of cancer have had their treatment evolve as rapidly as metastatic renal cell carcinoma (mRCC). Since 2005, six new targeted therapies with proven efficacy have been approved for the treatment of mRCC. The downside is that our knowledge about the mechanisms of action of these therapies and the intrinsic and extrinsic mechanism of resistance has not evolved equally fast, and many questions remain unanswered. The only approved agent to date in the European Union for patients who progress on sunitinib or sorafenib is everolimus. The results of the phase III trial comparing axitinib vs. sorafenib after failure on sunitinib, bevacizumab, temsirolimus, or cytokines have recently been published, and axitinib has recently been licensed by the Food and Drugs Administration. Other phase III trials that are being conducted include a comparison between everolimus plus bevacizumab and everolimus after failure on tyrosine kinase inhibitors, and between temsirolimus and sorafenib after failure on sunitinib. In this article, we will review the available evidence from clinical studies on sequential therapy for mRCC, including those that are still in progress. In addition, information on the mechanism of resistance or tolerance to first-line therapy, recommendations of the main practice guidelines for second-line treatment, potential therapies for third or successive treatment lines, and the major reasons why patients who progress may benefit from a change of mechanism of action will also be discussed.