Faculty Publications

Purpose To investigate the efficacy and safety of axitinib, an oral, potent, and selective inhibitor of vascular endothelial growth factor (VEGF) receptors 1, 2, and 3 in patients with metastatic renal cell carcinoma (mRCC) refractory to prior therapies that included, but were not limited to, sorafenib. Patients and Methods In this multicenter, open-label, phase II study, patients with sorafenib-refractory mRCC received a starting dose of axitinib 5 mg orally twice daily. A one-arm, single-stage design was used to estimate the primary end point of objective response rate (ORR), defined by RECIST (Response Evaluation Criteria in Solid Tumors). Secondary end points included safety, duration of response, progression-free survival (PFS), overall survival (OS), and patient-reported outcomes. Results Of 62 patients recruited, 100% had received prior sorafenib, and 74.2% had received two or more prior systemic treatments. The axitinib dose was titrated to greater than 5 mg twice daily in 53.2% of patients, and 35.5% of patients had the dose modified to less than 5 mg twice daily. In 62 patients evaluable for response, the ORR was 22.6%, and the median duration of response was 17.5 months. Median PFS and OS times were 7.4 months (95% CI, 6.7 to 11.0 months) and 13.6 months (95% CI, 8.4 to 18.8 months), respectively. All-causality grade 3 to 4 adverse events included hand-foot syndrome (16.1%), fatigue (16.1%), hypertension (16.1%), dyspnea (14.5%), diarrhea (14.5%), dehydration (8.1%), and hypotension (6.5%). Conclusion Axitinib has antitumor activity in patients with mRCC refractory to prior VEGF-targeted therapy, including sorafenib. Toxicities were mild to moderate and were manageable. A randomized, phase III trial to compare axitinib with sorafenib in patients who have mRCC refractory to one prior first-line therapy regimen is underway. J Clin Oncol 27:4462-4468. (C) 2009 by American Society of Clinical Oncology

Purpose To determine the impact of adjuvant androgen deprivation therapy (ADT) for patients who have node-positive prostate cancer in the prostate-specific antigen (PSA) era. Patients and Methods We used linked Surveillance, Epidemiology and End Results-Medicare data to construct a cohort of men who underwent radical prostatectomy ( RP) between 1991 and 1999 and who had positive regional lymph nodes. We classified men as receiving adjuvant ADT if they received ADT within 120 days of RP, and we compared them to the men who had not received adjuvant ADT. We used propensity scores to balance potential confounders of receiving adjuvant ADT (ie, tumor characteristics, extent of nodal disease, demographics, receipt of radiation therapy) and Cox proportional hazard methods to measure the impact of adjuvant ADT on overall survival ( OS), stratified by propensity score quintile. We conducted a sensitivity analysis that used 90, 150, 180, and 365 days as the definition for adjuvant ADT. Results A total of 731 men were identified, 209 of whom received ADT within 120 days of RP. There was no statistically significant difference in OS between the adjuvant ADT and non-ADT group (HR, 0.97; 95% CI, 0.71 to 1.27). There was no statistically significant survival difference with 90, 150, 180, and 365 days as the adjuvant ADT definition. Conclusion Deferring immediate ADT in men with positive lymph nodes after RP may not significantly compromise survival. Because observational studies should be considered hypothesis-generating studies, these results should be validated in a prospective fashion in a similar patient population.

The Third Cambridge Conference on Innovations and Challenges in Renal Cancer, a symposium held in Cambridge, Massachusetts, June 27-28, 2008, and chaired by Michael B. Atkins, was convened to discuss the current state of knowledge in the field, critique new data, stimulate communication among those involved in basic and clinical research, and offer recommendations for further study. Four main topics were discussed: genetics and molecular biology of renal cell cancer, staging and prognosis, systemic therapy, and correlative science and biomarkers in stage IV disease. The conference format combined brief presentations with extended periods of discussion. The conclusions and recommendations are summarized in this paper and presented in more detail in the individual papers that follow. Cancer 2009;115(10 suppl):2247-51. (C) 2009 American Cancer Society.

The mammalian target of rapamycin (mTOR) is clearly an important therapeutic target for advanced renal cell carcinoma (RCC), although its mechanisms of activation are not completely understood. In first-line treatment of patients who have both advanced RCC and multiple risk factors for short survival, temsirolimus improves overall survival (OS) compared with interferon. In patients whose tumors have progressed after sunitinib and/or sorafenib therapy, everolimus improves progression-free survival compared with placebo. Beyond the initial phase 3 studies demonstrating efficacy, many important questions remain in the clinical application of mTOR inhibition and in developing other inhibitors of PI3K/Akt/mTOR signaling. Important objectives of current and future clinical investigations include a more detailed description of the molecular pathology of RCC and identification of potential biomarkers that are predictive of tumor sensitivity to PI3K/Akt/mTOR targeted therapies. This information may identify other groups of RCC patients that are likely to benefit from inhibition of this signaling pathway. Additional questions concern mechanisms by which tumors become resistant to mTOR inhibitor therapy and how such resistance can be defeated. Possible mechanisms include the loss of feedback inhibition of insulin receptor substate/PI3K signaling resulting from the inhibition of mTOR complex 1 by rapamycin analogs and the activating phosphorylation of Akt by mTOR complex 2. Laboratory studies indicate that these resistance mechanisms could be countered by using other targeted agents in combination with mTOR inhibitors. Cancer 2009; 115(10 suppl):2313-20. (C) 2009 American Cancer Society.

The mammalian target of rapamycin (mTOR) protein complex functions as an integration center for various intracellular signaling pathways involving cell cycle progression, proliferation, and angiogenesis. These pathways are frequently dysregulated in cancer, and therefore mTOR inhibition is a potentially important antitumor target. Commercially available mTOR inhibitors include rapamycin (i.e., sirolimus) and temsirolimus. Other agents under investigation include everolimus and deforolimus. mTOR inhibition has been studied in various solid tumors, including breast, gynecologic, gastrointestinal, prostate, lung, and head and neck cancers. Studies have focused on mTOR inhibition as a monotherapy or in combination with other drugs based on the principle that inhibiting as many targets as possible reduces the emergence of drug resistance. Temsirolimus is currently the only mTOR inhibitor that is specifically labeled for treatment of solid tumors. However, preclinical studies and early-phase trials are rapidly evolving. Additionally, research is further defining the complicated mTOR pathways and how they may be disordered in specific malignancies. To address these issues, NCCN convened a task force to review the underlying physiology of mTOR and related cellular pathways, and to review the current status of research of mTOR inhibition in solid tumors.

Purpose: We assessed the efficacy of the oral multitargeted tyrosine kinase inhibitor sunitinib in patients with metastatic clear cell renal cell carcinoma. Materials and Methods: Patients with metastatic clear cell renal cell carcinoma were enrolled in this multicenter, phase II clinical trial. Major eligibility requirements were clear cell renal cell carcinoma histology, prior nephrectomy, measurable metastases and failed prior cytokine therapy as a result of disease progression. Sunitinib was given orally as second line therapy in 6-week cycles of 50 mg daily for 4 weeks, followed by 2 weeks off drug per treatment cycle. Response to sunitinib was rigorously assessed by an independent third party core imaging laboratory (central review). Results: Of 106 patients enrolled in the study 105 were evaluated for response. As determined by independent third party assessment, the objective response rate was 33% (95% Cl 24%-43%) with a median response duration of 14.0 months. Median time to progression and median progression-free survival in the 105 evaluable patients was 10.7 and 8.8 months, respectively. Median survival was 23.9 months and 43 patients remained alive at a median followup of 29.7 months. Conclusions: The results of this trial demonstrate the efficacy of sunitinib for metastatic renal cell carcinoma. The optimal integration of surgery and sunitinib treatment requires further prospective investigation.

BACKGROUND: Interferon alfa is widely used for metastatic renal-cell carcinoma but has limited efficacy and tolerability. Temsirolimus, a specific inhibitor of the mammalian target of rapamycin kinase, may benefit patients with this disease. METHODS: In this multicenter, phase 3 trial, we randomly assigned 626 patients with previously untreated, poor-prognosis metastatic renal-cell carcinoma to receive 25 mg of intravenous temsirolimus weekly, 3 million U of interferon alfa (with an increase to 18 million U) subcutaneously three times weekly, or combination therapy with 15 mg of temsirolimus weekly plus 6 million U of interferon alfa three times weekly. The primary end point was overall survival in comparisons of the temsirolimus group and the combination-therapy group with the interferon group. RESULTS: Patients who received temsirolimus alone had longer overall survival (hazard ratio for death, 0.73; 95% confidence interval [CI], 0.58 to 0.92; P=0.008) and progression-free survival (P<0.001) than did patients who received interferon alone. Overall survival in the combination-therapy group did not differ significantly from that in the interferon group (hazard ratio, 0.96; 95% CI, 0.76 to 1.20; P=0.70). Median overall survival times in the interferon group, the temsirolimus group, and the combination-therapy group were 7.3, 10.9, and 8.4 months, respectively. Rash, peripheral edema, hyperglycemia, and hyperlipidemia were more common in the temsirolimus group, whereas asthenia was more common in the interferon group. There were fewer patients with serious adverse events in the temsirolimus group than in the interferon group (P=0.02). CONCLUSIONS: As compared with interferon alfa, temsirolimus improved overall survival among patients with metastatic renal-cell carcinoma and a poor prognosis. The addition of temsirolimus to interferon did not improve survival. (ClinicalTrials.gov number, NCT00065468 [ClinicalTrials.gov].). Copyright 2007 Massachusetts Medical Society.

Background Estramustine phosphate is a mustard-oestradiol conjugate, and has hormonal and non-hormonal effects. In phase II trials of patients with cancer, response to microtubule inhibitors increases when these drugs are combined with estramustine. We aimed to assess whether combining estramustine with chemotherapy increases survival in patients with castration-refractory prostate cancer. Methods We systematically searched for randomised clinical trials that compared chemotherapy regimens with and without estramustine in patients with histologically-proven prostate cancer and were published between 1966 and 2004. Data from these studies were verified centrally and updated individual patient data were analysed. The primary endpoint was overall survival. Secondary endpoints were prostate-specific antigen (PSA) response, time to PSA progression, and toxicity. A Cox regression model that was stratified by trial and adjusted for covariates at baseline was used. Findings The initial search identified seven eligible trials that included 742 patients, from which data from five trials including 605 patients had been collected. Individual patient data from two trials (137 patients) were no longer available. The 605 patients had been accrued between Jan 1, 1993 and Dec 1, 2003 and randomly assigned to chemotherapy plus estramustine or to chemotherapy without estramustine. Chemotherapy (with or without estramustine) consisted of docetaxel, paclitaxel, ixabepilone, and vinblastine. Median follow-up was 2.8 years (range 0.0-3.4), and 510 deaths had occurred by the end of follow-up. Cox regression analysis stratified by trial showed that concentrations of serum haemoglobin (p < 0.0001), use of chemotherapy plus estramustine (p = 0.008), performance status (p = 0.002), and serum PSA concentrations (p = 0.04) were associated independently with overall survival. Overall survival was significantly better in patients assigned chemotherapy plus estramustine (adjusted hazard ratio [HR] 0.77 [95% CI 0.63-0.93], p = 0.008). Estimated absolute increase in overall survival when estramustine was added to chemotherapy was 9.5% (SE 4.0) at 1 year after randomisation. We did not note a significant association between treatment effect on overall survival and age, concentration of serum haemoglobin, performance status, or serum PSA concentration. Patients who received chemotherapy plus estramustine had a better PSA response than those who received chemotherapy without estramustine (RR 0.53 [0.38-0.72], p < 0.0001). Time to PSA progression was significantly longer in patients assigned chemotherapy plus estramustine than in those assigned chemotherapy without estramustine (HR 0.74 [0.58-0.94], p = 0.01). Patients assigned chemotherapy and estramustine had more grade 3 or grade 4 thromboembolic events compared with those assigned chemotherapy without estramustine (12 of 271 vs 1 of 275). Interpretation In patients with castration-refractory prostate cancer, addition of estramustine to chemotherapy increases time to PSA progression and overall survival compared with chemotherapy without estramustine. However, this benefit should be balanced with the risk of increased thromboembolic events in patients who receive estramustine and chemotherapy in combination compared with chemotherapy without estramustine.

We introduce a new study design in which patients are evaluated early in their treatment for disease progression. Our design is appropriate when lack of progression, both early and late, is the criterion for treatment success. An initial cohort of n(1) patients is followed until the last one has been evaluated. If enough of these patients are progression free (PF) at an early time point, t(1) after arrival, a second cohort is recruited until n(2) total patients are evaluable for PF survival at the final time t(2). Otherwise, the trial is terminated for futility both early in time and with a minimal number of patients. Patients in the initial cohort who are PF at t(1) continue on study and are again evaluated at t(2). The design permits early stopping for rapid progression of disease, an indication of futility both for cytotoxic and newer non-cytotoxic targeted therapies. The design tests the composite hypothesis of a probability p(1) of being PF at t(1) and p(2) of being PF at t(2) given PF at t(1). Power and type I error are maintained at design point levels over a wide range of parameters p(1) and p(2). No distributional assumptions are needed other than the binomial, so the design provides rigorous power analysis for this type of study. Tables of optimal designs are supplied for a broad range of requirements.

Background Axitinib (AG-013736) is an oral, potent, and selective inhibitor of vascular endothelial growth factor receptors 1, 2, and 3. We aimed to assess the activity and safety of axitinib in patients with metastatic renal-cell cancer who had failed on previous cytokine-based treatment. Methods Between Oct 3, 2003, and April 7, 2004, 52 patients were enrolled. All patients who had at least one measurable target lesion received axitinib orally (starting dose 5 mg twice daily). The primary endpoint was objective response (ie, percentage of patients with confirmed complete response or partial response by use of Response Evaluation Criteria In Solid Tumors [RECIST] criteria. Secondary endpoints were duration of response, time to progression, overall survival, safety, pharmacokinetics, and patient-reported health-related quality of life. This trial is registered on the clinical trials site of the US National Cancer Institute website http://www.clinicaltrials.gov/ct/show/ NCT00076011. Findings In an intention-to-treat analysis, two complete and 21 partial responses were noted, for an objective response rate of 44.2% (95% CI 30.5-58.7). Median response duration was 23.0 months (20.9-not estimable; range 4.2-29.8). However, 12 of 23 initial responders progressed with response duration ranging from 4.2 months to 26.5 months. Additionally, 22 patients showed stable disease for longer than 8 weeks, including 13 patients with stable disease for 24 weeks or longer. Four patients had early disease progression. Three patients had missing response data. Median time to progression was 15.7 months (8.4-23.4, range 0.03-31.5) and median overall survival was 29.9 months (20.3-not estimable; range 2.4-35.8). Treatment-related adverse events included diarrhoea, hypertension, fatigue, nausea, and hoarseness. Treatment-related hypertension occurred in 30 patients and resolved with antihypertensive treatment in all but eight patients, of whom seven patients had a history of hypertension at baseline. Interpretation Axitinib shows clinical activity in patients with cytokine-refractory metastatic renal-cell cancer. Although 28 patients had grade 3 or grade 4 treatment-related adverse events, these adverse events were generally manageable and controlled by dose modification or supportive care, or both. Further studies are needed to confirm these findings.