Double-blind, randomized trial of docetaxel plus vandetanib versus docetaxel plus placebo in platinum-pretreated metastatic urothelial cancer

Targeted therapy in advanced bladder cancer: what have we learned?

Despite advances in the treatment of other genitourinary malignancies, no novel therapies have been approved by the US Food and Drug Administration for urothelial carcinoma (UC) in the last 20 years. To date, no clinical trials of targeted agents in UC have led to improvements in survival compared with cytotoxic therapy. This article outlines representative trials of targeted therapies in UC and discusses the significance of genetic preselection in trial design as a method to optimize responses to these agents, thus, hopefully expanding the armamentarium of treatment options against this lethal disease.

Receptor tyrosine kinase inhibitors: Are they real tumor killers?

Inhibiting tumor growth by targeting the tumor vasculature was first proposed by Judah Folkman almost 40 years ago. Since then, different approaches and numerous drugs and agents have been developed to achieve this goal, either with the aim of inhibiting tumor neoangiogenesis or normalizing the tumor vasculature. Among the most promising therapeutic targets are receptor tyrosine kinases (RTKs), some of which are predominantly expressed on tumor endothelial cells, although they are sometimes also present on tumor cells. The majority of RTK inhibitors investigated over the past two decades competes with ATP at the active site of the kinase and therefore block the phosphorylation of intracellular targets. Some of these drugs have been approved for therapy, whereas others are still in clinical trials. Here, we discuss the scientific basis, current status, problems and future prospects of RTK inhibition in anti-tumor therapy.

MPDL3280A (anti-PD-L1) treatment leads to clinical activity in metastatic bladder cancer

There have been no major advances for the treatment of metastatic urothelial bladder cancer (UBC) in the last 30 years. Chemotherapy is still the standard of care. Patient outcomes, especially for those in whom chemotherapy is not effective or is poorly tolerated, remain poor. One hallmark of UBC is the presence of high rates of somatic mutations. These alterations may enhance the ability of the host immune system to recognize tumour cells as foreign owing to an increased number of antigens. However, these cancers may also elude immune surveillance and eradication through the expression of programmed death-ligand 1 (PD-L1; also called CD274 or B7-H1) in the tumour microenvironment. Therefore, we examined the anti-PD-L1 antibody MPDL3280A, a systemic cancer immunotherapy, for the treatment of metastatic UBC. MPDL3280A is a high-affinity engineered human anti-PD-L1 monoclonal immunoglobulin-G1 antibody that inhibits the interaction of PD-L1 with PD-1 (PDCD1) and B7.1 (CD80). Because PD-L1 is expressed on activated T cells, MPDL3280A was engineered with a modification in the Fc domain that eliminates antibody-dependent cellular cytotoxicity at clinically relevant doses to prevent the depletion of T cells expressing PD-L1. Here we show that MPDL3280A has noteworthy activity in metastatic UBC. Responses were often rapid, with many occurring at the time of the first response assessment (6 weeks) and nearly all were ongoing at the data cutoff. This phase I expansion study, with an adaptive design that allowed for biomarker-positive enriched cohorts, demonstrated that tumours expressing PD-L1-positive tumour-infiltrating immune cells had particularly high response rates. Moreover, owing to the favourable toxicity profile, including a lack of renal toxicity, patients with UBC, who are often older and have a higher incidence of renal impairment, may be better able to tolerate MPDL3280A versus chemotherapy. These results suggest that MPDL3280A may have an important role in treating UBC-the drug received breakthrough designation status by the US Food and Drug Administration (FDA) in June 2014.

Second-line therapies in metastatic urothelial carcinoma

Patients with relapsed or refractory urothelial carcinoma (UC) face a poor prognosis and a dearth of available treatment options that improve their survival. End-organ function and performance status play a vital role in the choice of second-line therapies. Evidence supporting the use of cytotoxic chemotherapy, as single agents or in combination, arises from small phase 2 studies with modest responses. With the evolution of genomic testing in UC, several pathways amenable to available targeted therapies have emerged. Encouraging patient participation in clinical trials is critical to improve patient outcomes and to advance the current modest treatment armamentarium.

Future directions and targeted therapies in bladder cancer

There are substantial unmet needs for patients with metastatic urothelial carcinoma (UC). First-line cisplatin-based chemotherapy regimens yield a median survival of 12 to 15 months and long-term survival in 5% to 15%. Salvage systemic therapy yields a median survival of 6 to 8 months. Hence, the discovery of novel therapeutic targets is of paramount importance. Recent molecular analyses have provided insights regarding molecular tumor tissue alterations on multiple platforms. A multidisciplinary effort using innovative clinical trial designs and exploiting preclinical signals of robust activity guided by predictive biomarkers may provide much needed clinical advances in therapy for advanced UC.

Risk of treatment-related deaths with vascular endothelial growth factor receptor tyrosine kinase inhibitors: a meta-analysis of 41 randomized controlled trials

Background

Vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs) have widely been used in advanced cancer. However, these drugs may also lead to serious adverse events. The present meta-analysis aimed to determine the overall incidence and risk of deaths due to VEGFR-TKIs with more detailed subgroup analysis.

Materials and methods

PubMed, Web of Science, and Cochrane databases were searched for randomized controlled trials (RCTs) that compared VEGFR-TKIs with non-VEGFR-TKIs in the treatment of solid cancer. Pooled incidence, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using random-effects or fixed-effects models based on the heterogeneity of included trials.

Results

A total of 14,139 participants from 41 RCTs were enrolled. The pooled incidence of death due to VEGFR-TKIs was 1.9% (95% CI: 1.6%–2.3%) with an OR of 1.85 (95% CI: 1.33–2.58; P<0.01) when compared with control groups. On subgroup analysis, significantly increased risk of death was found in patients with nonsmall-cell lung cancer (OR: 2.37; 95% CI: 1.19–4.73; P=0.01) and colorectal cancer (OR: 2.84; 95% CI: 1.02–7.96; P=0.05). Among different VEGFR-TKIs, sorafenib and sunitinib had significant risk of death when compared with control arms, respectively. VEGFR-TKIs in combination with other antineoplastic agents, but not VEGFR-TKI monotherapy, significantly increased the risk of treatment-related deaths. No heterogeneity was noted across all the prespecified subgroups regarding ORs.

Conclusion

The present work pointed out a significantly increased risk of death due to VEGFR-TKIs. Close monitoring should be emphasized in patients receiving these drugs.

Dovitinib: rationale, preclinical and early clinical data in urothelial carcinoma of the bladder

INTRODUCTION

Bladder cancer (BC) is the third and fifth cancer in men in terms of incidence and mortality in the US. Overexpression and mutations of fibroblast growth factor receptor 3 (FGFR3) are frequently found in BC and can represent a very interesting therapeutic target. Different FGFR3-targeted strategies have been investigated through in vitro and in vivo settings, including FGFR3 tyrosine kinase inhibitors such as dovitinib .

AREAS COVERED

The authors review the data that provide a scientific rationale for FGFR3-targeted therapy in BC. They also provide an evaluation of the currently available in vitro and in vivo data on the use of dovitinib in BC patients.

EXPERT OPINION

The development and progression of BC rely on a very complex signaling network that involves many different receptors aside from FGFR3 and VEGFR2. The involved signaling network can also be very different from one BC to the other, and can also evolve through time in the same patient. Inhibiting only one single target may thus not be sufficient to achieve a complete downstream oncogenic signaling blockage. Additionally, in vitro data on the use of neutralizing monoclonal antibodies targeting FGFR3 show that it can be a more efficient strategy to reach the same goal, with the potential advantage of less toxicity.

Emerging antiangiogenics for renal cancer

INTRODUCTION

Antiangiogenic therapy is considered to be the backbone of treatment strategy in metastatic renal cell carcinoma (mRCC). New, more focused, targeted drugs are emerging, while other targeted drugs oriented toward resistance or alternative mechanisms are under development.

AREAS COVERED

Antiangiogenic agents include two types of agents: the monoclonal antibody, targeting vascular endothelial growth factor (VEGF), bevacizumab and the tyrosine kinase inhibitors (TKIs). Data regarding efficacy and safety of these agents are reported. Differences between the first generation of TKIs, sunitinib, sorafenib, and the new generation, pazopanib, axitinib and tivozanib are also detailed. Most of these agents have been approved in the treatment of kidney cancer in specific settings of the disease.

EXPERT OPINION

The class of antiangiogenic drugs for treatment of mRCC is already relatively full. After 'me-too' drugs, more targeted drugs against VEGFR have been developed but have to demonstrate a benefit in first-line treatment. Another option for the development is to combine a known drug with an antiangiogenic inhibition profile and at least one additional target involved in resistance to an antiangiogenic or in an alternative pathway. The cost of approach with targeted drugs, including antiangiogenics, has led to a tremendous increase in the cost of care in mRCC.

Second-line systemic therapy for metastatic urothelial carcinoma of the bladder

While platinum-based combination chemotherapy leads to high response rates in patients with advanced urothelial cancer of the bladder, most patients will ultimately progress and optimal treatment in the second-line setting still needs to be determined. Advanced age, poor performance status, comorbidities and rapidly progressive disease have rendered accrual into trials difficult. Vinflunine is the only cytotoxic agent to demonstrate survival benefit in a randomized Phase III setting, but its response rate is disappointing and it has not been compared with other currently used agents such as taxanes. Recent years have seen a better definition of prognostic and predictive factors in patients with relapsed urothelial cancer. In addition, several trials have investigated novel biological agents to target chemoresistant disease. This review provides an update on the current systemic management of advanced urothelial cancer on progression following first-line chemotherapy, and discusses emerging data from recent Phase II/III trials.

Targeted therapies in urothelial carcinoma

PURPOSE OF REVIEW

Greater understanding of the biology and genetics of urothelial carcinoma is helping to identify and define the role of molecules and pathways appropriate for novel-targeted therapies. Here, we review the targeted therapies that have been reported or are in ongoing urothelial carcinoma clinical trials, and highlight molecular targets characterized in preclinical and clinical studies.

RECENT FINDINGS

Trials in nonmuscle-invasive bladder cancer are evaluating the role of immunotherapy and agents targeting vascular endothelial growth factor (VEGF) or fibroblast growth factor receptor-3. In muscle-invasive bladder cancer, neoadjuvant studies have focused on combining VEGF agents with chemotherapy; adjuvant studies are testing vaccines and agents targeting the human epidermal growth factor receptor 2, p53, and Hsp27. In the first-line treatment of metastatic urothelial carcinoma, tubulin, cytotoxic T-lymphocyte antigen 4, Hsp27, and p53 are novel targets in clinical trials. The majority of targeted agents studied in urothelial carcinoma are in the second-line setting; new targets include CD105, polo-like kinase-1, phosphatidylinositide 3-kinases (PI3K), transforming growth factor β receptor/activin receptor-like kinase β, estrogen receptor, and the hepatocyte growth factor receptor (HGFR or MET).

SUMMARY

Development of targeted therapies for urothelial carcinoma is still in early stages, consequently there have been no major therapeutic advances to date. However, greater understanding of urothelial carcinoma and solid tumor biology has resulted in a proliferation of clinical trials that could lead to significant advances in treatment strategies.

Safety and efficacy of addition of VEGFR and EGFR-family oral small-molecule tyrosine kinase inhibitors to cytotoxic chemotherapy in solid cancers: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The approach of combining cytotoxic chemotherapy with oral small molecule tyrosine kinase inhibitors (TKIs) has been explored in a large number of randomized trials, in a variety of tumor. We performed a systematic review and meta-analysis to evaluate the safety and efficacy of this therapeutic approach.

PATIENTS AND METHODS

PubMed and the ASCO databases were searched up to March 2013. We included randomized trials in which the FDA approved vascular endothelial growth factor receptor (VEGFR) or epidermal growth factor receptor-family (EGFR)-targeted TKI in combination with chemotherapy was compared with chemotherapy alone in patients with any type of solid cancer. The endpoints included safety [fatal adverse events (FAEs), treatment discontinuation, any severe (grade 3 or 4) adverse events (AEs), and individual severe AEs] and efficacy [progression-free survival (PFS), and overall survival (OS)]. The pooled relative risk (RR) or hazard ratio (HR) were calculated.

RESULTS

A total of 16,011 patients from 43 trials were included. Compared with chemotherapy alone, the addition of a TKI significantly increased the risk of FAEs (RR, 1.63; 95% CI, 1.32-2.01), treatment discontinuation (RR, 1.80; 95% CI, 1.58-2.06), and any severe AE (RR, 1.25; 95% CI, 1.16-1.36). The addition of a TKI was associated with a significant improvement in PFS (HR, 0.82; 95% CI, 0.76-0.89), but not OS (HR, 0.99; 95% CI, 0.95-1.03).

CONCLUSIONS

It is important for physicians to weigh the risk of toxicity versus the modest PFS benefit associated with chemotherapy plus TKI in patients with solid cancers.

A phase II safety and efficacy study of the vascular endothelial growth factor receptor tyrosine kinase inhibitor pazopanib in patients with metastatic urothelial cancer

BACKGROUND

Vascular endothelial growth factor (VEGF) is produced by bladder cancer cell lines in vitro and expressed in human bladder tumor tissues. Pazopanib is a vascular endothelial receptor tyrosine kinase inhibitor with anti-angiogenesis and anti-tumor activity in several preclinical models. A 2-stage phase II study was conducted to assess the activity and toxicity profile of pazopanib in patients with metastatic, urothelial carcinoma.

METHODS

Patients with one prior systemic therapy for metastatic urothelial carcinoma were eligible. Patients received pazopanib at a dose of 800 mg orally for a 4-week cycle.

RESULTS

Nineteen patients were enrolled. No grade 4 or 5 events were experienced. Nine patients experienced 11 grade 3 adverse events. Most common toxicities were anemia, thrombocytopenia, leucopenia, and fatigue. For stage I, none of the first 16 evaluable patients were deemed a success (complete response or partial response) by the Response Evaluation Criteria In Solid Tumors criteria during the first four 4-week cycles of treatment. Median progression-free survival was 1.9 months. This met the futility stopping rule of interim analysis, and therefore the trial was recommended to be permanently closed.

CONCLUSIONS

Pazopanib did not show significant activity in patients with urothelial carcinoma. The role of anti-VEGF therapies in urothelial carcinoma may need further evaluation in rational combination strategies.

Analysis of plasma cytokines and angiogenic factors in patients with pretreated urothelial cancer receiving Pazopanib: the role of circulating interleukin-8 to enhance the prognostic accuracy

Background:

Pazopanib achieved the end point of clinical activity in pretreated patients with urothelial cancer in a single-group, phase 2 trial. The objective was to identify biological predictors of clinical benefit to pazopanib in these patients.

Methods:

EDTA blood samples were collected at baseline (T0) and after 4 weeks (T1) of treatment, together with radiological imaging in all 41 patients to analyse plasma circulating angiogenic factor levels by multiplex ELISA plates. Changes from T0 to T1 in marker levels were matched with response with the covariance analysis. Univariable and multivariable analyses evaluated the association with overall survival (OS), adjusted for prespecified clinical variables. Net reclassification improvement (NRI) tested the performance of the recognised Cox model.

Results:

Increasing IL8^T1 level associated with lower response probability at covariance analysis (P=0.010). Both IL8^T0 (P=0.019) and IL8^T1 (P=0.004) associated with OS and the prognostic model, including clinical variables and IL8^T1 best-predicted OS after backward selection. The NRI for this model was 39%.

When analysed as a time-varying covariate, IL8^T1 level<80 pg ml⁻¹ portended significantly greater response (∼80%) and 6-month OS (∼60%) probability than level⩾80.

Conclusion:

IL8-level changes during pazopanib allowed for a prognostic improvement and were associated with response probability.

Emerging drugs for urothelial carcinoma

INTRODUCTION

Advanced urothelial carcinoma is associated with a poor prognosis. In the metastatic setting, the response rate to first-line, cisplatin-containing chemotherapy is high, but survival is poor. Second-line treatment options are limited. Advanced age at diagnosis and the presence of comorbidities often preclude treatment with cisplatin-containing regimens.

AREAS COVERED

This review addresses the current therapy of urothelial carcinoma, the unmet needs in treatment and the status of drug development in this disease. The molecular targets identified and efforts to incorporate targeted agents into therapy will be addressed.

EXPERT OPINION

There have been no major advances in the treatment of urothelial carcinoma in three decades. Despite high response rates in the first-line setting, survival is limited. Major impediments to improved outcomes include poor durability of response to first-line chemotherapy and lack of second-line treatments. Better understanding in tumor biology has identified multiple targets in urothelial carcinoma; however, such discoveries have yet to lead to the incorporation of targeted agents into the routine treatment of urothelial carcinoma. Multiple ongoing clinical trials are investigating the use of targeted agents in urothelial carcinoma. Continued efforts are underway to better understand the molecular drivers of disease and such efforts are likely to identify additional therapeutic targets.

Cabozantinib (XL184) for the treatment of locally advanced or metastatic progressive medullary thyroid cancer

Cabozantinib (XL184) is an oral multiple receptor tyrosine kinase inhibitor manufactured by Exelixis Inc., CA, USA. It mainly inhibits three tyrosine kinase receptors: MET, VEGFR2 and RET. In both preclinical and clinical studies it has been shown to inhibit tumor angiogenesis, invasiveness and metastases. The most frequent side effects are fatigue, diarrhea, decreased appetite, nausea, weight loss and palmar-plantar erythrodysesthesia. A Phase III clinical trial (EXAM study) of XL184 versus placebo in advanced and progressive medullary thyroid cancer showed a 28 versus 0% overall response rate and a progression-free survival of 11.2 versus 4.0 months (hazard ratio: 0.28; 95% CI: 0.19-0.40; p < 0.0001) in patients treated with cabozantinib and placebo, respectively. The drug has been approved by the US FDA for the treatment of advanced/progressive metastatic medullary thyroid cancer in the USA. The EMA is now evaluating its approval in Europe.

Six-month progression-free survival as the primary endpoint to evaluate the activity of new agents as second-line therapy for advanced urothelial carcinoma

OBJECTIVE

Second-line systemic therapy for advanced urothelial carcinoma (UC) has substantial unmet needs, and current agents show dismal activity. Second-line trials of metastatic UC have used response rate (RR) and median progression-free survival (PFS) as primary endpoints, which may not reflect durable benefits. A more robust endpoint to identify signals of durable benefits when investigating new agents in second-line trials may expedite drug development. PFS at 6 months (PFS6) is a candidate endpoint, which may correlate with overall survival (OS) at 12 months (OS12) and may be applicable across cytostatic and cytotoxic agents.

METHODS

Ten second-line phase II trials with individual patient outcomes data evaluating chemotherapy or biologics were combined for discovery, followed by external validation in a phase III trial. The relationship between PFS6/RR and OS12 was assessed at the trial level using Pearson correlation and weighted linear regression, and at the individual level using Pearson chi-square test with Yates continuity correction.

RESULTS

In the discovery dataset, a significant correlation was observed between PFS6 and OS12 at the trial (R(2) = 0.55, Pearson correlation = 0.66) and individual levels (82%, Қ = 0.45). Response correlated with OS12 at the individual level less robustly (78%, Қ = 0.36), and the trial level association was not statistically significant (R(2) = 0.16, Pearson correlation = 0.37). The correlation of PFS6 (81%, Қ = 0.44) appeared stronger than the correlation of response (76%, Қ = 0.17) with OS12 in the external validation dataset.

CONCLUSIONS

PFS6 is strongly associated with OS12 and appears more optimal than RR to identify active second-line agents for advanced UC.

Addition of vandetanib to pegylated liposomal doxorubicin (PLD) in patients with recurrent ovarian cancer. A randomized phase I/II study of the AGO Study Group (AGO-OVAR 2.13)

BACKGROUND

PLD is a standard treatment in patients with recurrent platinum-resistant or refractory ovarian cancer. Vandetanib is an oral once daily administered inhibitor of VEGFR-, EGFR- and RET-signaling with activity in combination with chemotherapy in some solid tumours. We aimed to establish a feasible combination therapy of PLD and vandetanib in ovarian cancer.

METHODS

Eligible patients were treated with PLD 50 mg/m(2) q28 and vandetanib 100 mg/d po. It was planned to recruit at least 10 patients evaluable for toxicity over 2 treatment cycles. Primary endpoints were tolerability and safety; secondary endpoint was efficacy.

RESULTS

Fourteen of 15 registered patients started treatment and were evaluable for toxicity. Three patients (21%) stopped after first cycle (PD, withdrawal of consent, nausea/vomiting). The remaining 11 patients were treated for at least 2 cycles. Dose reductions of PLD and vandetanib were indicated in 4 (29%) and 5 patients (36%), respectively. The following G3/4 toxicities occurred per patient: 2 (14%) elevated liver enzymes G3, 2 (14%) neutropenia G3/4, 5 (36%) PPE G3/4, 2 (14%) mucositis G3. Tyrosine kinase inhibitor attributed side effects like hypertension or bowel perforations were not reported. Toxicity led to cessation of treatment in 4 patients (29%). Ten patients were evaluable for response: PR 1, SD 4. The median PFS was 6.7 months and median OS was 11.1 months.

CONCLUSIONS

The combination of PLD 50 mg/m(2)q28 and vandetanib 100 mg/d is feasible, but may be intolerable due to reported toxicity.

Molecular targets on the horizon for kidney and urothelial cancer

As whole-genome sequencing technology rapidly advances, the insights gained from deciphering cancer genomes are shifting the paradigm in the diagnosis and treatment of cancer with the promise of individualized treatment for each patient. Information gained in this way is extensive for certain cancers, but fairly limited in renal cell carcinomas and urothelial carcinoma. Mutations in multiple, potentially druggable genes have been identified in urothelial carcinomas; however, the association between molecular alterations and clinical outcome has not yet been robustly demonstrated. Data in this area are emerging in renal cell carcinoma, leading to the development of targeted agents that have improved overall survival. Unfortunately, these treatments rarely yield complete responses, are not curative, and development of resistance ensues. This Review will focus on the biology of non-hormonally driven urological cancers. We discuss how approaches using whole-genome sequencing can facilitate the discovery of biomarkers of drug sensitivity in both renal cell carcinomas and urothelial carcinomas. For renal cell carcinomas, we will describe how genomic and epigenomic mining has uncovered novel genes and pathways involved in tumorigenesis, tumour classification and mechanisms of resistance in the various subsets of this disease and the potential for exploiting these discoveries in the clinic.

Immunomodulation via Chemotherapy and Targeted Therapy: A New Paradigm in Breast Cancer Therapy?

Cytotoxic chemotherapy in the treatment of tumors has traditionally been thought to be immunosuppressive. Increasing evidence suggests the contrary and has introduced the concept of 'immunogenic' chemotherapy or, in other words, the concept that the innate and adaptive immune systems are critical in determining the long-term efficacy of some cytotoxic-based (and radiotherapy-based) regimens. The underlying mechanisms how these therapies can stimulate an antitumor immune response have been demonstrated recently. In this article, we review the background of this new paradigm and how combinations of traditional agents with the new immunotherapeutic therapies may significantly advance our treatment of breast cancer.

Impact of response to prior chemotherapy in patients with advanced urothelial carcinoma receiving second-line therapy: implications for trial design

BACKGROUND

The prognostic impact of response to prior chemotherapy independent of performance status (PS), hemoglobin (Hb), liver metastasis (LM), and time from prior chemotherapy (TFPC) in the context of second-line therapy for advanced urothelial carcinoma (UC) is unknown.

METHODS

Six phase II trials evaluating second-line therapy (n = 504) were pooled. Patients who received prior therapy for metastatic disease were eligible for analysis if Hb, LM, PS, and TFPC were available. Response by Response Evaluation Criteria in Solid Tumors 1.0 to first-line therapy was recorded. Progression-free survival (PFS) and overall survival (OS) were calculated from the date of registration using the Kaplan-Meier method.

RESULTS

A total of 275 patients were evaluable for analysis. Patients received gemcitabine-paclitaxel, cyclophosphamide-paclitaxel, pazopanib, docetaxel plus vandetanib/placebo, or vinflunine (2 trials). Those with prior response (n = 111) had a median OS of 8.0 months (95% confidence interval [CI], 6.8-9.4), compared with 5.9 months (95% CI, 5.0-6.6) for those without prior response (n = 164). Those with prior response had a median PFS of 3.0 months (95% CI, 2.6-4.0) compared with 2.6 months (95% CI, 2.0-2.8) in patients without response. Multivariable analysis did not reveal a significant independent impact of prior response on PFS and OS.

CONCLUSIONS

Best prior response in patients receiving prior chemotherapy for metastatic disease did not confer an independent prognostic impact with second-line therapy for advanced UC. Given that the setting of prior chemotherapy (metastatic or perioperative) has not appeared significant in a prior study, patients who received prior chemotherapy in perioperative or metastatic settings may be enrolled in the same second-line trial stratified for PS, Hb, LM, and TFPC.

Nanoparticle albumin-bound paclitaxel for second-line treatment of metastatic urothelial carcinoma: a single group, multicentre, phase 2 study

BACKGROUND

No standard treatment exists for patients with platinum-refractory urothelial cancer. Taxanes and vinflunine are commonly used, but response is less than 20% with no survival benefit. In this phase 2 study, we assessed efficacy and tolerability of nanoparticle albumin-bound (nab) paclitaxel in platinum-refractory urothelial cancer.

METHODS

We did an open-label, single-group, two-stage study at five centres in Canada. We enrolled patients aged at least 18 years with histologically confirmed, locally advanced, or metastatic measurable urothelial cancer, with documented progression on or within 12 months of treatment with one previous platinum-containing regimen. Patients received nab-paclitaxel at 260 mg/m(2) intravenously every 3 weeks. Treatment continued until disease progression or occurrence of unacceptable toxic effects. The primary endpoint was objective tumour response, defined by a complete response (CR) or partial response (PR) according to Response Evaluation Criteria In Solid Tumors (version 1.0) criteria. Tumour response and safety were assessed in all patients who received at least one cycle of nab-paclitaxel. This study is registered with ClinicalTrials.gov, number NCT00683059.

FINDINGS

We enrolled 48 patients between Oct 16, 2008, and June 23, 2010. Patients received a median of six cycles (range one to 15). 47 patients were evaluable; one (2·1%) had a CR and 12 (25·5%) had PRs, resulting in an overall response of 27·7% (95% CI 17·3-44·4). The most frequently recorded adverse events of any grade were fatigue (38 of 48; 79%), pain (37 of 48; 77%), alopecia (34 of 48; 71%), and neuropathy (30 of 48; 77%). The most frequently recorded adverse events of grade 3 or higher were pain (11 of 48; 23%), fatigue (five of 48; 23%), hypertension (three of 48; 6%), neuropathy (three of 48, 6%), and joint stiffness or pain (two of 48; 4%).

INTERPRETATION

Nab-paclitaxel was well tolerated in this population of patients with pretreated advanced urothelial cancer with an encouraging tumour response. These results warrant further study of nab-paclitaxel in second-line treatment of urothelial cancer.

FUNDING

Abraxis Bioscience, Celgene.

Clinical activity of sorafenib in a previously treated advanced urothelial cancer patient

A male patient, with advanced urothelial carcinoma, who had previously received cisplatin, was treated with sorafenib off-licence for 10.7 months. Evaluation of tumour response with computed tomography scans indicated a reduction in tumour size and necrosis of the metastases within 2 months. Progression-free survival was 10.5 months. Side effects were manageable and not beyond the National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0 grade 2. Molecular profiling of two of the proposed targets of sorafenib, platelet-derived growth factor receptor β and vascular endothelial growth factor receptor 2, of the patient's tumour lesion showed high and intermediate expression levels in the tumour as compared with the surrounding non-neoplastic tissue. In contrast to previous reports, we report a clinically meaningful effect of sorafenib in a patient with advanced urothelial carcinoma. Hence, it appears that a fraction of patients with this disease are sensitive to this compound. To identify subpopulations of responders, we propose that clinical trials evaluating sorafenib and other targeted drugs should be biomarker-driven and designed with endpoints that consider the mode of action of the specific compound.

Incidence and risk of hypertension with vandetanib in cancer patients: a systematic review and meta-analysis of clinical trials

AIM

To perform a systematic review and meta-analysis of published clinical trials to determine incidence rate and overall risk of hypertension with vandetanib in cancer patients.

METHODS

A comprehensive literature search for studies published up to March 2012 was performed. Summary incidence rates, relative risk (RR), and 95% confidence intervals (CI) were calculated employing fixed- or random-effects models depending on the heterogeneity of the included trials.

RESULTS

A total of 11 trials with 3154 patients were included for the meta-analysis. The summary incidences of all-grade and high-grade hypertension in patients with cancer were 24.2% [95% confidence interval (CI), 18.1-30.2%] and 6.4% (95% CI, 3.3-9.5%), respectively. Subgroup analysis demonstrated that the pooled incidences of all-grade and high-grade hypertension were 21.8% [95% CI, 15-30.5%] and 7.6% (95% CI, 2.8-18.8%), respectively, among non-small-cell lung cancer (NSCLC) patients, and 32.1% (95% CI: 27.3-37.3%) and 8.8% (5.9%-12.9%), respectively, among MTC patients, and 15.4 (95% CI: 3.2-33.7%) and 3.4% (95% CI: 1%-11.1%) respectively, among non-MTC/NSCLC tumors patients. Furthermore, vandetanib was associated with a significant increased risk of all-grade hypertension (RR 5.1, 95% CI: 3.76-6.92, P = 0.000) and high-grade hypertension (RR 8.06, 95% CI: 3.41-19.04, P = 0.000) in comparison with controls.

CONCLUSIONS

There is a significant risk of developing hypertension in cancer patients receiving vandetanib. Appropriate monitoring and treatment is strongly recommended to prevent cardiovascular complications.

Time from prior chemotherapy enhances prognostic risk grouping in the second-line setting of advanced urothelial carcinoma: a retrospective analysis of pooled, prospective phase 2 trials

BACKGROUND

Outcomes for patients in the second-line setting of advanced urothelial carcinoma (UC) are dismal. The recognized prognostic factors in this context are Eastern Cooperative Oncology Group (ECOG) performance status (PS) >0, hemoglobin level (Hb) <10 g/dl, and liver metastasis (LM).

OBJECTIVES

The purpose of this retrospective study of prospective trials was to investigate the prognostic value of time from prior chemotherapy (TFPC) independent of known prognostic factors.

DESIGN, SETTING, AND PARTICIPANTS

Data from patients from seven prospective trials with available baseline TFPC, Hb, PS, and LM values were used for retrospective analysis (n=570). External validation was conducted in a second-line phase 3 trial comparing best supportive care (BSC) versus vinflunine plus BSC (n=352).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cox proportional hazards regression was used to evaluate the association of factors, with overall survival (OS) and progression-free survival (PFS) being the respective primary and secondary outcome measures.

RESULTS AND LIMITATIONS

ECOG-PS >0, LM, Hb <10 g/dl, and shorter TFPC were significant prognostic factors for OS and PFS on multivariable analysis. Patients with zero, one, two, and three to four factors demonstrated median OS of 12.2, 6.7, 5.1, and 3.0 mo, respectively (concordance statistic=0.638). Setting of prior chemotherapy (metastatic disease vs perioperative) and prior platinum agent (cisplatin or carboplatin) were not prognostic factors. External validation demonstrated a significant association of TFPC with PFS on univariable and most multivariable analyses, and with OS on univariable analyses. Limitations of retrospective analyses are applicable.

CONCLUSIONS

Shorter TFPC enhances prognostic classification independent of ECOG-PS >0, Hb <10 g/dl, and LM in the setting of second-line therapy for advanced UC. These data may facilitate drug development and interpretation of trials.

Targeted agents in second-line bladder cancer therapy

The treatment of metastasized urothelial cancer has been evolving in recent years. In particular, in the second-line setting after the failure of platinum-containing therapy, options are few and besides vinflunine, the recently approved standard in Europe, well-designed highly selective clinical trials may be possible alternatives for patients in this palliative situation. However, targeted therapy approaches have not achieved the same results in urothelial cancer as for instance in renal cell carcinoma. Many of the new targeted drugs have been investigated as single agents in phase II clinical trials without convincing oncologic outcome. This review aims to highlight the most relevant clinical studies examining targeted agents in the second-line setting of metastasized transitional carcinoma of the urothelium.

Antiangiogenic Agents, Chemotherapy, and the Treatment of Metastatic Transitional Cell Carcinoma

A 69-year-old man with a 100 pack-year history of smoking developed gross hematuria. His medical history included hypertension, a silent myocardial infarction, and a cerebrovascular accident complicated by seizures. Cystoscopy and biopsy showed a 4-cm mass at the right ureteral orifice positive for a high-grade papillary transitional cell carcinoma (TCC) with muscularis propria invasion (Fig 1). The computed tomography (CT)/positron emission tomography (PET) scan of the chest, abdomen, and pelvis showed hydronephrosis and hydroureter with marked cortical thinning and multiple bilateral PET-avid pulmonary nodules, with the largest in the left upper lung measuring 3.0 × 2.5 cm (Figs 2A, 3A), biopsy of which showed invasive high-grade urothelial carcinoma. The patient consented to join a clinical trial for metastatic TCC (USON [US Oncology Network study] 06040) involving treatment with gemcitabine, cisplatin, and sunitinib (GCS) 37.5 mg per day.1Four days later, he experienced a 10-day hospitalization for acute pancreatitis and neutropenia. Sunitinib was discontinued, and he completed four additional cycles of GC. CT/PET showed that the right ureteral mass and all lung nodules had regressed or disappeared (Figs 2B, 3B). The largest remaining lung nodule at 1.4 cm showed no metabolic activity. He underwent a radical cystoprostatectomy and right nephroureterectomy, disclosing residual high-grade urothelial carcinoma infiltrating the full thickness of the ureteral wall. There was carcinoma in situ of the bladder, and 42 nodes were negative for cancer. The surgery was followed by a small, uncomplicated myocardial infarction. A scheduled left thoracotomy to remove the remaining nodule was cancelled. No additional chemotherapy was administered, and the patient remains free of recurrence 2 years from initiation of chemotherapy. The 1.4-cm nodule has calcified and remains stable and metabolically inactive. He has no sequelae of chemotherapy or surgery, with a creatinine level of 1.35 mg/dL.

Long-term survival results of a randomized phase III trial of vinflunine plus best supportive care versus best supportive care alone in advanced urothelial carcinoma patients after failure of platinum-based chemotherapy

BACKGROUND

To compare long-term, updated overall survival (OS) of patients with advanced transitional cell carcinoma of the urothelium (TCCU) treated with vinflunine plus best supportive care (BSC) or BSC alone, after failure of platinum-based chemotherapy.

PATIENTS AND METHODS

Three hundred and seventy patients were randomly assigned in a phase III trial and allocated (2:1) to vinflunine (320 or 280 mg/m(2)) plus BSC or BSC alone. The first report (Bellmunt J, Theodore C, Demkov T et al. Phase III trial of vinflunine plus best supportive care compared with best supportive care alone after a platinumcontaining regimen in patients with advanced transitional cell carcinoma of the urothelial tract. J Clin Oncol 2009; 27(27): 4454-4461) had a median follow-up of 22.1 m and the current report has a follow-up of 45.4 m.

RESULTS

Three hundred and fifty-two patients had died (censoring rate 5%). In the intention-to-treat (ITT) population, the median OS was 6.9 m and 4.6 m for vinflunine plus BSC versus BSC alone, respectively (n.s.). In multivariate Cox analysis, the addition of vinflunine was independently correlated with improved survival (HR: 0.719; 95% CI:0.570-0.906, P = 0.0052). In the eligible population, the median OS in both the arms was 6.9 and 4.3 m, respectively (HR: 0.78; 95% CI:0.61-0.96; P = 0.0227), indicating an estimated 22% reduction in the risk of death.

CONCLUSIONS

The updated OS data confirm the positive treatment effect of vinflunine on survival that was previously reported. These results are consistent over time and confirm that vinflunine is a valuable option for second-line treatment in patients with advanced TCCU after failure of platinum-based regimens.

Gemcitabine, Cisplatin, and sunitinib for metastatic urothelial carcinoma and as preoperative therapy for muscle-invasive bladder cancer

BACKGROUND

Data support chemotherapy combined with antiangiogenic therapy in metastatic urothelial cancer (mUC) and muscle-invasive bladder cancer (MIBC). We investigated the efficacy and safety of gemcitabine, cisplatin, and sunitinib (GCS) in mUC and MIBC in parallel phase II trials.

PATIENTS AND METHODS

Trial 1 enrolled 36 patients with mUC who were chemotherapy naive; trial 2 enrolled 9 patients with MIBC. The primary endpoints for trials 1 and 2 were response rate and pathologic complete response, respectively. GCS was given as first-line treatment for patients with mUC and as neoadjuvant therapy for patients with MIBC. The Simon minimax 2-stage design was used for an objective response rate in trial 1 and for the pathologic complete response rate in trial 2.

RESULTS

The initial trial 1 GCS dose was gemcitabine 1000 mg/m(2) intravenously, days 1 and 8; cisplatin 70 mg/m(2) intravenously, day 1; and sunitinib 37.5 mg orally daily, days 1 to 14 of a 21-day cycle. These doses proved intolerable. The doses of gemcitabine and cisplatin were subsequently reduced to 800 and 60 mg/m(2), respectively, without an improvement in drug delivery, and the trial was closed. This lower-dose regimen was applied in trial 2, which was stopped early due to excess toxicity. Grade 3 to 4 hematologic toxicities occurred in 70% (23/33) of patients in trial 1 and 22% (2/9) of patients in trial 2. In trial 1, the response rate was 49% (95% CI, 31%-67%); in trial 2, the pathologic complete response was 22% (2/9). Due to early closure secondary to toxicity, the sample sizes of both trials were small.

CONCLUSIONS

Delivery of GCS was hampered by excessive toxicity in both advanced and neoadjuvant settings.

Addition of vandetanib to chemotherapy in advanced solid cancers: a meta-analysis

The addition of vandetanib to chemotherapy has been shown to have a marked effect on patients with advanced cancers who had failed previous chemotherapy. We carried out a meta-analysis to determine the efficacy and safety of vandetanib compared with chemotherapy in patients with advanced cancers. For this meta-analysis, we selected randomized clinical trials that compared vandetanib-based therapy (VBT) with the matched chemotherapy or placebo alone in patients with advanced cancers. The outcomes included overall survival (OS), progression-free survival (PFS), the objective response rate, and toxicities. Hazard ratios (HRs) and odds ratios were reported with 95% confidence intervals (CIs). A total of 14 eligible trials were included for the meta-analysis, with 2995 patients in the VBT group and 2479 patients in the control group. A significant improvement was observed in PFS (HR 0.76, 95% CI 0.68-0.86 in all cancers, HR 0.80, 95% CI 0.70-0.90 in lung cancer, HR 0.54, 95% CI 0.40-0.74 in thyroid cancer) and in objective response rate (odds ratio 2.09, 95% CI 1.42-3.07) in the VBT group. However, no significant difference was found in OS (HR 0.96, 95% CI 0.90-1.03). The subgroups of patients with non-small-cell lung cancer who benefited from vandetanib therapy were identified as those with a history of smoking (HR 0.87, 95% CI 0.80-0.95) and an adenocarcinoma histology (HR 0.85, 95% CI 0.77-0.94). In addition, patients who received VBT had an increased incidence of adverse events such as rash, diarrhea, and neutropenia. The addition of vandetanib to chemotherapy significantly improves PFS in patients with locally advanced or metastatic cancers, especially lung and thyroid cancer.

Changes in circulating pro-angiogenic cytokines, other than VEGF, before progression to sunitinib therapy in advanced renal cell carcinoma patients

OBJECTIVES

This study included a cohort of advanced renal cell carcinoma patients treated with sunitinib. Since resistance to sunitinib may be mediated through angiogenic cytokines other than VEGF, we measured the circulating levels of three pro-angiogenic cytokines: basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), and interleukin (IL)-6.

METHODS

Cytokines were measured at baseline and on the first day of each treatment cycle until progression in 85 advanced kidney cancer patients treated with sunitinib using a quantitative sandwich enzyme immunoassay (ELISA) technique.

RESULTS

Even though no statistically significant differences in the titers of the three cytokines were observed between baseline and the time of progression in the whole patient cohort, in 45.3, 46.6, and 37.3% of the patients a more than 50% increase between baseline and the time of progression was shown in circulating IL-6, bFGF, and HGF, respectively. Furthermore, this increase was more than 100% in 37.3, 44, and 30.6% of the patients, respectively. We also demonstrated that, in these patients, cytokines tended to increase and to remain high immediately before progression.

CONCLUSIONS

In a large percentage of kidney cancer patients, progression is preceded by a significant increase in pro-angiogenic cytokines other than VEGF.

Clinical Significance of ErbB Receptor Family in Urothelial Carcinoma of the Bladder: A Systematic Review and Meta-Analysis

The prognostic importance of examining ErbB receptor family expression in human bladder cancer remains uncertain. Using published evidence, we examined the clinical value and the updated results of clinical trials targeting ErbB receptor family members. Twenty-seven articles from 65 references related to ErbB receptor expression assessment in bladder cancer were reviewed. The estimates included the association significance, hazard ratios, and 95% confidence intervals (CIs) from actuarial curves and survival analyses. A meta-analysis was done on those reports using univariate log-rank tests or a Cox-regression model. The methods of analysis and study subjects chosen varied widely among studies. The overall risks of disease progression for patients with EGFR or ErbB2 overexpression were 4.5 (95% CI: 2.5–8.4) and 1.1 (95% CI: 0.6–1.9), and the risks of mortality were 3.0 (95% CI: 1.6–5.9) and 1.1 (95% CI: 1.0–1.2), respectively. However, the significance of coexpression patterns of the ErbB receptor family remains controversial. None of six clinical trials yielded convincing results for blockading ErbB receptor signaling in urothelial carcinoma. The results of this analysis suggest that assessing co-expression patterns of the ErbB family may provide better prognostic information for bladder cancer patients.

Pazopanib in advanced and platinum-resistant urothelial cancer: an open-label, single group, phase 2 trial

BACKGROUND

The development of new drugs for patients with refractory urothelial cancer is still an unmet medical need. Preclinical evidence lends support to a rationale for targeting of the VEGF or platelet-derived growth-factor axis. We therefore investigated the activity and safety of pazopanib, a multitarget drug with antiangiogenic activity, in patients with urothelial cancer.

METHODS

In an open-label, single-group, phase 2 study, patients (aged ≥18 years) with relapsed or refractory urothelial cancer were given pazopanib 800 mg per day, orally. They were treated until disease progression or prohibitive toxicity occurred. The primary endpoint was the proportion of patients who achieved a confirmed objective response, defined as complete or partial response, after independent review, and was analysed by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT01031875.

FINDINGS

The trial has been completed. 21 (51%) of 41 patients enrolled were given pazopanib as third-line or further-line treatment. 26 (63%) patients had an Eastern Cooperative Oncology Group performance status of 1 or 2. Seven patients had a confirmed objective response (17·1%, 95% CI 7·2-32·1), all of which were partial responses. The most frequent treatment-related grade 3 adverse events were hypertension (three [7%]), fatigue (two [5%]), and gastrointestinal and vaginal fistulisations (two each [5%]). One patient died as a result of duodenal fistulisation that was related to tissue response of bulky tumour masses.

INTERPRETATION

Pazopanib has single-agent activity in patients with heavily pretreated metastatic urothelial cancer, and warrants further study in this setting. Particular attention should be paid to patients with bulky tumour masses adjacent to viscera because fistulisation is probably related to the response to pazopanib and is the most frequent serious adverse event.

FUNDING

Fondazione IRCCS Istituto Nazionale dei Tumori provided the grant. GlaxoSmithKline provided the study drug and provided funding for the independent radiological review.

Vandetanib for the treatment of metastatic medullary thyroid cancer

Medullary thyroid cancer (MTC) represents an aggressive form of thyroid malignancy. Some may occur spontaneously or can be associated with Multiple Endocrine Neoplasia syndromes, or Familial Medullary Thyroid Cancer syndrome. In these patients, the protooncogene RET (rearranged during transfection) is mutated. In patients who have unresectable or metastatic disease, the long term prognosis is poor. New treatments for this disease have focused on the use of targeted agents that inhibit the receptor tyrosine kinase of RET. One of these treatments, Vandetanib (Caprelsa, Astra Zeneca), recently has received approval from the Food and Drug Administration for the treatment of patients with progressive locally advanced and/or metastatic disease. This review highlights the studies that led to the drug's approval, and discusses on the potential financial costs of treatment and side effects of this therapy. The main clinical studies evaluating Vandetanib for the treatment of other solid tumors will also be reviewed.

Novel molecular targets for the therapy of urothelial carcinoma

INTRODUCTION

First-line platinum-based combinations are active in locally advanced and metastatic urothelial carcinoma; however, long-term outcomes including disease-specific and overall survival remain suboptimal. In addition, approximately 40 - 50% of patients with advanced urothelial carcinoma have coexisting medical issues that preclude the use of cisplatin-based therapy. Improvements in our understanding of the molecular mechanisms of urothelial tumorigenesis have led to first-generation clinical trials evaluating novel agents targeting molecular pathways. These are particularly relevant in regard to subpopulations. Novel trial designs warrant consideration to accelerate accrual.

AREAS COVERED

In this review, novel molecular targets for the therapy of urothelial carcinoma, as well as recently completed and ongoing clinical trials utilizing novel targeted agents, are discussed. A Medline search with key words, abstracts reported at national conferences on urothelial carcinoma and NCI clinical trial identifiers was used for this review.

EXPERT OPINION

Improved understanding of molecular biology has identified a number of new molecular targets, but there is a seeming absence of one dominant molecular driver for urothelial cancer. An adaptive and biomarker-derived strategy may be warranted. Clinical trials utilizing targeted agents are ongoing and results are awaited.