49LBA Final results of a Phase II randomised study of cediranib (RECENTIN™) in patients with advanced renal cell carcinoma (RCC)

Novel agents and approaches for advanced renal cell carcinoma

PURPOSE

Targeted agents have changed the treatment paradigm for advanced renal cell carcinoma. Approved agents with demonstrated efficacy are sunitinib, sorafenib, pazopanib, bevacizumab, temsirolimus and everolimus. However, there is an unmet need for new agents to improve the clinical outcome in treatment naïve patients and in those who are disease refractory or intolerant to traditional and targeted therapies. Many novel targeted agents, of which some have different mechanisms of action than approved agents, and immunomodulatory agents are currently in development for renal cell carcinoma.

MATERIALS AND METHODS

We searched ClinicalTrials.gov to identify novel agents for advanced renal cell carcinoma in ongoing phase II/III clinical trials. Using the relevant agents as search terms we reviewed the medical literature for mechanisms of action and efficacy, and safety results to date, including data from recent major oncology meetings.

RESULTS

A total of 11 novel targeted agents, including next generation tyrosine kinase inhibitors, and inhibitors of vascular endothelial growth factor ligand binding, Akt and endothelial cell proliferation, and 3 novel immunomodulatory agents, are under evaluation for renal cell carcinoma. In addition to ongoing phase II/III trials of emerging agents, head-to-head, crossover and combination trials of approved targeted agents are under way.

CONCLUSIONS

Although many agents are approved or in development for renal cell carcinoma, comparative effectiveness data are lacking. Ongoing and future head-to-head trials using appropriate comparators are essential to update renal cell carcinoma treatment guidelines. Future research should be aimed at identifying agents that improve patient outcomes and have decreased toxicity compared with currently approved agents with the goal of complete remission.

Current and future systemic treatments for renal cell carcinoma

Systemic treatment of renal cell carcinoma has changed dramatically since 2007, with the development and approval of six new agents, which target complex molecular pathways regulating tumour angiogenesis and cell proliferation and survival. These treatments have significantly improved survival times in metastatic renal cell carcinoma, but remain palliative. A number of newer agents are in clinical development, which offer theoretical advantages over existing treatments, and research methodologies are adapting with the aim of defining an individualised approach to therapy which exploits the underlying tumour biology. This review will provide an overview of current and emerging systemic treatments and how they might be integrated with surgical therapy, with a particular focus on advanced, clear cell metastatic renal cell carcinoma.

Development of second-generation VEGFR tyrosine kinase inhibitors: current status

The vascular endothelial growth factor (VEGF) signaling pathway appears to be the dominant pathway involved in tumor angiogenesis, providing a rationale for targeting the VEGF receptors (VEGFR-1, -2, and -3) in the treatment of cancers. In particular, VEGF signaling is thought to be important in renal cell carcinoma (RCC) because of the deregulation of the pathway through nearly uniform loss of the von Hippel Lindau protein. The tyrosine kinase inhibitors (TKIs) sorafenib, sunitinib, and pazopanib are approved by the US Food and Drug Administration for the treatment of advanced RCC; however, these multitargeted agents inhibit a wide range of kinase targets in addition to the VEGFRs, resulting in a range of adverse effects unrelated to efficient VEGF blockade. This article reviews recent advances in the development of the second-generation VEGFR TKIs, including the more selective VEGFR TKIs tivozanib and axitinib, and focuses on the potential benefits of novel inhibitors with improved potency and selectivity.

Challenges and opportunities for converting renal cell carcinoma into a chronic disease with targeted therapies

Optimum efficacy is the primary goal for any cancer therapy, and entails controlling tumour growth and prolonging survival as far as possible. The prognosis for patients with metastatic renal cell carcinoma (mRCC) has greatly improved with the introduction of targeted therapies. This review examines the development and efficacy of targeted agents for the management of mRCC, the challenges offered by their rapid emergence, and discusses how mRCC treatment may evolve in the future. Improvements in progression-free survival and overall survival rates, observed with targeted agents, indicate that it may now be possible to change mRCC from a rapidly fatal and largely untreatable condition into a chronic disease. The major challenges to further advances in targeted therapy for mRCC include overcoming drug resistance, identifying the most effective sequence or combination of targeted agents, optimising clinical trial design and managing the cost of treatment.

A two-part phase II study of cediranib in patients with advanced solid tumours: the effect of food on single-dose pharmacokinetics and an evaluation of safety, efficacy and imaging pharmacodynamics

BACKGROUND

Cediranib (RECENTIN™) is an oral, highly potent VEGF inhibitor. This study evaluated the effect of food on the pharmacokinetics of cediranib and compared the administration of continual cediranib via two dosing strategies using this as a platform to investigate pharmacodynamic imaging biomarkers.

METHODS

Sixty patients were randomised to receive two single doses of cediranib in either fed/fasted or fasted/fed state (Part A). In continual dosage phase (Part B), patients were randomised to a fixed-dose or dose-escalation arm. Exploratory pharmacodynamic assessments were performed using DCE-MRI and CT enhancing fraction (EnF).

RESULTS

In part A, plasma AUC and C (max) of cediranib were lower in the presence of food by a mean of 24 and 33%, respectively (94% CI: AUC, 12-34% and C (max), 20-43%), indicating food reduces cediranib plasma exposure. In part B, cediranib 30 mg/day appeared to be the most sustainable for chronic dosing. Continuous cediranib therapy was associated with sustained antivascular effects up to 16 weeks, with significant reductions in DCE-MRI parameters and CT EnF.

CONCLUSIONS

It is recommended that cediranib be administered at least 1 h before or 2 h after food. Evidence of antitumour activity was observed, with significant sustained effects upon imaging vascular parameters.