4523 Background: Chemoradiation therapy (CRT) is an organ conserving approach in the treatment of locally advanced bladder cancer. Chemoradiation is thought to potentially result in immunogenic stimulation, and bladder cancer is often a tumor with high immune cell infiltration. Thus, we aimed to profile the tumor immune microenvironment of bladder cancer and identify prognostic immune biomarkers for CRT response by profiling tumor samples from NRG/RTOG 0524 and 0712, two prospective trials of CRT in muscle invasive bladder cancer (MIBC). Methods: Pretreatment tissue samples from both trials were profiled using Cofactor Genomics ImmunoPrism, an RNA sequencing assay that uses gene expression profiles to quantify immune cell populations in the tumor microenvironment (TME). Differential gene expression was estimated for different immune cell type proportions across samples. Kaplan-Meier survival analysis and log rank tests were performed to evaluate differences in overall survival (OS) stratified by genes influenced by immune cell proportions or genes associated with immune response signatures. Results: A total of 70 samples (43 from RTOG 0524 and 27 from RTOG 0712) underwent analysis using the ImmunoPrism assay. Immune cell proportions were as follows: CD8 T cells: median 1.2%, CD4 T cells: median 0.8%, Treg cells: median 9.2%, CD19 B cells: median 5.1%, M2 macrophages: median 0.8%, M1 macrophages: median 0%. Unbiased clustering based on gene expression profiles driven by immune cell proportions demonstrated two groups: cluster 1 with a low percentage of immune cells and shorter OS (median 31 months) and cluster 2 with a high percentage of immune cells and longer OS (median 101 months, p = 0.036). Higher expression of genes associated with T cell infiltration ( CD8A and ICOS) was associated with improved OS (104 vs 35 months, p = 0.028, HR = 0.48 (0.25 – 0.94), p = 0.031) as was higher expression of IDO1, which is associated with the interferon gamma pathway (104 vs 35 months, p = 0.042, HR = 0.49 (0.24 – 0.99), p = 0.046). Conclusions: Bladder tumors have a wide range of immune cell infiltration in the TME. Increased immune cell proportions are prognostic for OS following CRT, as well as a higher expression of genes associated with T cell infiltration interferon gamma signaling. These findings have implications for the integration of immunotherapy in the definitive management of MIBC; and can be explored further in the ongoing NRG/SWOG 1806 trial.

Purpose/Objective(s)RTOG 1115 was a randomized phase III trial evaluating the addition of orteronel (TAK-700), a novel CYP17A1 inhibitor, to dose escalated radiation plus ADT in men with high risk, localized prostate cancer. Originally designed to evaluate overall survival, the trial was halted early due to discontinuation of orteronel development in prostate cancer. We report here the initial primary endpoint analysis.Materials/MethodsThe study was designed to enroll 900 men with high-risk prostate cancer (Gleason 9-10, PSA > 20, or clinical stage T2 or higher with Gleason ≥ 8). Ultimately, 238 patients were enrolled (May 2012-Sept 2014), and randomized 1:1 to receive standard therapy (Arm A), or standard therapy plus two years of twice daily orteronel (Arm B). Radiation therapy entailed dose-escalated external beam radiation (EBRT) to the prostate and pelvis to 45 Gy in 25 fractions, followed by a boost to 79.2 Gy using EBRT or either HDR or LDR. The analysis plan was reframed around detecting a reduction in rate of a composite biochemical failure endpoint (Phoenix biochemical failure, local/regional or distant disease, or salvage ADT). With 238 patients enrolled and followed, the study would have 70% power to detect a 40% decrease in the composite failure primary endpoint after 70 events had occurred.Results231 patients were evaluable for efficacy and toxicity, 115 in Arm A and 116 in Arm B, and median follow up was 6.2 years. Grade 3 adverse events were observed in 35% and 60% of men in Arm A and B, respectively, with most common being urinary or gastrointestinal disturbance. Time to grade 3 adverse event was significantly faster in Arm B (log rank P value < 0.001). There were four deaths due to adverse events, three of which were in Arm A, and all were deemed unlikely related to treatment. Notably, only 29% of men in Arm B received 80% or more of the planned dose of orteronel due to a variety of factors that impacted drug tolerability. With respect to the primary outcome, patients did well overall with 6-year failure rates of 22.5% and 16.1%, respectively, in Arms A and B (hazard ratio [HR] 0.83, 95% CI 0.47-1.48). By Phoenix definition, PSA failure was only 18.4% and 12.1% in Arms A and B through 6 years. Distant failure occurred in 10.0% and 4.0% of patients (HR 0.71, 95% CI 0.29-1.75). Quality of life outcomes will be reported separately. While all efficacy trends favored the experimental arm, due to the small number of patients and events none of the differences between arms achieved statistical significance.ConclusionThe addition of orteronel to dose escalated RT and ADT did not result in statistically significant improvement in efficacy outcomes, although results were limited by early termination of accrual and impaired drug tolerability. Intensification of hormonal therapy with better tolerated novel agents remains an appealing strategy for the treatment of high-risk localized prostate cancer.

Purpose/Objective(s) Quality of life (QOL) was assessed with the hypothesis that QOL and fatigue scores would not differ significantly between the ADT + RT (Arm A) and the experimental group receiving ADT + RT + oreteronel (Arm B). Materials/Methods In both arms, ADT with GnRH agonist was given for 24 mos, and dose escalated RT started 8-10 wks after initiation of ADT. In Arm B, oreteronel was given BID for 24 mos. QOL was measured with Expanded Prostate Cancer Index Composite (EPIC) and EQ-5D global QOL assessment. EPIC has 4 domains: bowel, urinary, sexual, and hormonal. EQ-5D index score was calculated using health states obtained from 5 dimensions, and a visual analog score (VAS). For EPIC, EQ-5D index and VAS, higher scores indicate better QOL. Fatigue was measured by the 7-item Patient-Reported Outcome Measurement Information System (PROMIS) short form. Total score is standardized into a T-score with mean of 50 and standard deviation of 10 with higher score representing more fatigue. Change scores, calculated as follow-up minus baseline, were compared between arms. Longitudinal analysis using repeated measures mixed effects models was conducted (prior to ADT [baseline], one wk prior to starting RT, last wk of RT, and 1 and 2.5 yrs after initiation of therapy). Results Of 231 eligible patients, 196 consented to QOL, 102 on Arm A and 94 on Arm B. Compliance prior to start of RT and end of RT was 83%. At 1 and 2.5 yrs, 80% and 62% of pts, respectively, completed the EPIC. There were no differences between any EPIC domain between arms from the start of RT through the end of follow-up. Men on oreteronel had a significantly greater decline in bowel score prior to starting RT then control patients (-6.12, 95% confidence interval [CI]: -9.24, -3.01 vs. -1.93, 95% CI: -4.48, 0.63, respectively, p=0.038). Arm B patients also had a statistically significant and clinically meaningful worse change in urinary score vs control from baseline to pre-RT (-2.33, 95% CI: -5.02, 0.36 vs. 1.38, 95% CI: -1.07, 3.83, respectively, p=0.043). No other timepoints were significant. The only sig. between arm difference in EPIC sexual and hormonal scores was also at pre-RT in favor of Arm A over Arm B; p=0.024 and p=0.0024 respectively). Fatigue was also greater in the oreteronel patients prior to starting RT (3.81, 95% CI: 1.88, 5.74 vs. 1.18, 95% CI: -0.23, 2.60, p=0.028). Conclusion The addition of oreteronel to RT and ADT resulted in greater declines in QOL prior to the start of RT but did not result in significant differences at any other time points. Although oreteronel development has been halted, the QOL results are encouraging for other drugs in this class that remain under investigation. In ongoing prospective trials, QOL impacts should be measured in conjunction with changes in clinical outcome and survival. This project was supported by grants UG1CA189867, U10CA180868, U10CA180822 from the National Cancer Institute and Takeda Pharmaceutical.

In 2017, there is no adjuvant systemic therapy proven to increase overall survival in non-metastatic renal cell carcinoma (RCC). The anti-PD-1 antibody nivolumab improves overall survival in metastatic treatment refractory RCC and is generally tolerable. Mouse solid tumor models have revealed a benefit with a short course of neoadjuvant PD-1 blockade compared to adjuvant therapy. Two ongoing phase 2 studies of perioperative nivolumab in RCC patients have shown preliminary feasibility and safety with no surgical delays or complications. The recently opened PROSPER RCC trial (A Phase 3 RandOmized Study Comparing PERioperative Nivolumab vs. Observation in Patients with Localized Renal Cell Carcinoma Undergoing Nephrectomy; EA8143) will examine if the addition of perioperative nivolumab to radical or partial nephrectomy can improve clinical outcomes in patients with high risk localized and locally advanced RCC. With the goal of increasing cure and recurrence-free survival (RFS) rates in non-metastatic RCC, we are executing a three-pronged, multidisciplinary approach of presurgical priming with nivolumab followed by resection and adjuvant PD-1 blockade. We plan to enroll 766 patients with clinical stage ≥T2 or node positive M0 RCC of any histology in this global, randomized, unblinded, phase 3 National Clinical Trials Network study. The investigational arm will receive two doses of nivolumab 240 mg IV prior to surgery followed by adjuvant nivolumab for 9 months. The control arm will undergo the current standard of care: surgical resection followed by observation. Patients are stratified by clinical T stage, node positivity, and histology. The trial is powered to detect a 14.4% absolute benefit in the primary endpoint of RFS from the ASSURE historical control of 55.8% to 70.2% at 5 years (HR = 0.70). The study is also powered to detect a significant overall survival benefit (HR 0.67). Key safety, feasibility, and quality of life endpoints are incorporated. PROSPER RCC exemplifies team science with a host of planned correlative work to investigate the impact of the baseline immune milieu and changes after neoadjuvant priming on clinical outcomes.

4527 Background: Linifanib (ABT-869) is a potent inhibitor of VEGF and PDGF receptor tyrosine kinases. Phase I study results suggested antitumor activity in advanced solid tumors including RCC. This study investigated the efficacy and safety of linifanib in patients with RCC following sunitinib failure. Methods: In this open-label, multicenter trial of oral linifanib 0.25 mg/kg (12.5-25.0 mg) daily, key eligibility criteria included PD within 100 days of enrollment after at least 2 cycles of sunitinib, prior nephrectomy, and adequate organ function. The primary endpoint was overall response rate (ORR) by central imaging. Secondary endpoints were PFS, OS, and TTP. Safety was assessed by NCI-CTCAE, v3.0. Results: 53 pts were enrolled from 8/07 to 10/08. The median age was 61 years. 81% of pts had clear-cell histology, and the median number of prior therapies was 2. All pts were previously treated with sunitinib. Response rate to prior sunitinib was 13.2%. Additional prior treatments included cytokines (23%), sorafenib (19%), temsirolimus (4%), and bevacizumab (17%). The ORR [95% CI] per RECIST was 9.4% [3.1, 20.7] (all responses confirmed on 2 visits >4 weeks apart), the median PFS was 5.4 months [3.6, 6.3], and the median OS was 13.3 months [10.8, not reached]. Pts with only 1 prior systemic therapy appeared to have PFS (HR 1.33, [0.71, 2.50], p=0.37) and OS (HR 0.9 [0.39, 2.09], p=0.81) that were similar to those with >1 prior therapy. The most common linifanib-related grade 3/4 adverse event (AE) was hypertension (HT) in 32% of pts. The most common linifanib-related any grade AEs were diarrhea, fatigue (74% each), HT (60%), nausea (51%), and hand-foot syndrome/skin reaction (40%). 46 pts had AE-related dose interruptions and 36 pts had AE-related dose reduction. At the time of analysis, 37 pts discontinued therapy due to PD (clinical, radiographic or AE related to PD), 8 discontinued due to AEs not related to PD, and 2 discontinued for other reasons. There were no deaths due to linifanib-related AEs. Conclusions: Linifanib demonstrated antitumor activity in RCC after sunitinib failure as assessed by ORR and PFS. Future monotherapy trials will utilize a fixed starting dose of 17.5 mg/day. Author Disclosure Employment or Leadership Position Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Abbott Laboratories Abbott Laboratories, Genentech, Novartis, Pfizer, Wyeth Abbott Laboratories Pfizer, Wyeth Abbott Laboratories

5101 Background: The recently demonstrated activity of inhibitors of TORC1 in RCC has raised the possibility that even greater effects may be achieved by targeting upstream of this pathway. Perifosine is a synthetic alkylphospholipid which inhibits Akt activity and also has cell-dependent effects upon the MAP-kinase pathway. Prior single-agent trials showed disease stabilization/regression in patients (pts) with advanced RCC; however, few pts were previously treated with a TKI. Therefore, we conducted a multi-center phase II trial to determine the safety and efficacy of perifosine in pts with advanced RCC refractory to VEGFR TKI. Methods: Primary objectives were to measure the % of pts progression-free at 12 weeks (wks) and overall progression-free survival (PFS) of perifosine (100 mg qhs). Secondary objectives included overall response rate (> PR), and safety, Eligibility: ECOG PS 0–1, pts with metastatic RCC who have RECIST defined progression on either sunitinib or sorafenib. Prior Rx with immunotherapy and bevacizumab was permitted. Normal organ and marrow function required. Results: From 4/07–10/08, 24 pts were treated at four sites. Median age 67 (range 47–78) and 16 were male; 90% of pts had predominantly clear cell histology. Prior sunitinib = 12; prior sorafenib = 12 (1.5 avg prior Rx). As of 12/08, all 24 pts were evaluable for PFS, response and toxicity as follows in the table . 6/24 pts remain on treatment (range 7 - 84 wks). Therapy was well tolerated with primarily Grade (G) 1 & 2 adverse events. G 3 & 4 events were: dyspnea (8%), hyponatremia (8%), pulmonary embolism (4%) and arthalgia (4%). Conclusions: Perifosine has promising activity in pts with RCC who have failed prior TKI therapy. The favorable toxicity profile suggests potential for combinational therapies with VEGF-targeted agents. Additional studies are under consideration to evaluate perifosine for clinical benefit in pts with previously treated RCC. [Table: see text] [Table: see text]

e16016 Background: The osteolysis marker NTX has shown prognostic significance in pts with bone metastases from a broad range of solid tumors, but its potential in pts with RCC has not been investigated. Methods: This was an exploratory correlative analysis of NTX levels and outcomes in the RCC subset of pts treated with zoledronic acid (ZOL) in a 21-month phase III trial (Rosen et al. J Clin Oncol. 2002). In North American pts in this study, urinary NTX was measured approximately every 3 mo and was expressed per mmol creatinine (CR). Endpoints included overall survival (OS), disease progression in bone, and pathologic fractures. Relative risks and 95% confidence intervals for pts with elevated NTX (NTX ≥ 64 nmol/mmol CR) versus normal NTX (< 64 nmol/mmol CR) were calculated by Cox regression for baseline and most recent (≤ 6 mo prior) NTX assessments. Results: Among 55 ZOL-treated RCC pts, 29 had baseline NTX data (median = 60 nmol/mmol CR). Whereas baseline NTX levels showed trends for outcomes, recent NTX levels profoundly correlated with outcomes ( Table ). An elevated recent NTX measurement correlated with a > 13-fold increased risk of death and a > 11-fold increased risk of progression in bone. Correlations were also significant for first and all on-study fractures. Conclusions: In pts with RCC receiving ZOL, serial NTX assessments may provide important prognostic insight. Although based on a small sample size, correlations between recent NTX levels and outcomes in RCC pts are more profound than those previously reported in pts with other solid tumors (Brown et al. J Natl Cancer Inst. 2005). Elevated NTX could alert physicians to the need to more closely monitor bone lesions and intervene to prevent fractures in RCC pts. This may be especially important in the context of new systemic therapies that are improving the outlook in the advanced RCC setting. [Table: see text] [Table: see text]

5024 Background: In a randomized phase III trial of patients (pts) with mRCC, sunitinib demonstrated a significant improvement in progression-free survival (PFS) and objective response rate (ORR) compared to IFN-a as first-line therapy (Proc ASCO 2006;24:2s [Abstract LBA3]). We present the most recent data from this trial and an analysis of prognostic factors. Methods: Untreated pts with clear-cell mRCC were randomized 1:1 to receive either sunitinib (repeated 6-week cycles of 50 mg/day orally for 4 weeks, followed by 2 weeks off treatment) or IFN-a (9 MU given subcutaneously three times weekly). The primary endpoint was PFS. Results: A total of 750 pts were randomized: 375 to sunitinib, 375 to IFN-a. The median duration of treatment is 11 months (range: <1–25) for sunitinib vs. 4 months (range: <1–22) for IFN-a. The updated ORR by investigator assessment is 44% (95% CI: 39, 49) for sunitinib vs. 11% (95% CI: 8, 15) for IFN-a (p <0.000001), including 4 complete responses for sunitinib and 2 for IFN-a. The median duration of response in the sunitinib group (n=165) is 12 months (95% CI: 10, 14) vs. 10 months (95% CI: 8, 17) in the IFN-a group (n=43). The median PFS is 11 months (95% CI: 10, 11) for sunitinib vs. 4 months (95% CI: 4, 5) for IFN-a. The median PFS for pts with 0 risk factors is 14 months (95% CI: 11, 16) for sunitinib vs. 8 months (95% CI: 7, 10) for IFN-a; 9 months (95% CI: 8, 11) vs. 4 months (95% CI: 4, 4), respectively, for pts with 1- 2 risk factors; 4 months (95% CI: 2, 10) vs. 1 month (95% CI: 1, 2), respectively, for pts with =3 risk factors. The sunitinib benefit in PFS extends across all MSKCC prognostic risk factor groups (HR=0.488; 95% CI: 0.406, 0.586). The baseline features that predict longer PFS (by investigator assessment) for the sunitinib group are hemoglobin =LLN (p=0.0043), corrected calcium =10 mg/dL (p=0.001), ECOG score of 0 (p=0.0005), number of metastatic sites 0 or 1 (p=0.0064), and time from diagnosis to treatment =1 yr (p=0.0002). Conclusions: Sunitinib is a reference standard for first-line treatment of mRCC, with significant improvement in PFS and ORR compared to IFN-a. The benefit of sunitinib extends across all subgroups of pts with mRCC. Previously defined MSKCC risk factors for mRCC predict longer PFS with sunitinib. No significant financial relationships to disclose.

The green fluorescent protein (GFP) of the jellyfish Aequorea victoria has revolutionized the study of protein localization and dynamics. GFP fusions permit analysis of proteins in living cells and offer distinct advantages over conventional immunofluorescence. Among these are lower background, higher resolution, robust dual color colocalization, and avoidance of fixation artifacts. In the case of Ras and Rho family proteins, GFP fusions have allowed breakthroughs in the understanding of how CAAX proteins are targeted to specific cell membranes and how signaling at different membranes can result in different cellular responses. GFP-tagged Rho proteins have also been informative in analyzing the interactions with the cytosolic chaperone, RhoGDI. The major disadvantages of studying GFP fusion proteins is that they are generally overexpressed relative to endogenous proteins, and the GFP tag can, in principle, affect protein function. Fortunately, in the case of Ras and Rho family proteins, a GFP tag at the N terminus seems to have little effect on protein targeting and function. Nevertheless, it is prudent to confirm GFP fusion protein data with the study of the endogenous protein. This chapter describes the tagging of Rho proteins with GFP and the analysis of GFP-Rho protein localization by epifluorescence and confocal microscopy. It further describes methods of analyzing endogenous Rho proteins as confirmation of data acquired using GFP-Rho fusion proteins. These techniques will be useful for anyone studying Rho protein function and are widely applicable to many cell types and signal transduction systems.

8167 Background: SU11248 is a novel, oral multi-targeted tyrosine kinase inhibitor with both anti-angiogenic and anti-tumor activity. In a phase 2 study (014) of SU11248 for the treatment of metastatic renal cell carcinoma following failure of 1 prior cytokine treatment, a 40% tumor response rate (25/63) has been reported (Motzer et al., ASCO 2005, submitted). This analysis describes the patient reported outcomes (PROs) in this trial. Methods: PROs were assessed using the FACIT-Fatigue scale (FACIT-Fatigue, score range = 0–52) and the EQ-5D health status visual analogue scale (EQ-VAS, score range = 0–100) in the first four 6-week cycles (4 weeks on treatment, 2 weeks off), weekly for FACIT-Fatigue and at the start and end of each 4-week treatment period for EQ-VAS. Of 63 patients enrolled, 62 participated in the baseline PRO assessment and 37 (59%) provided complete or near-complete data across four 6-week cycles. Results: At baseline, FACIT-Fatigue and EQ-VAS scores of these patients were slightly lower than those of the general population. Baseline FACIT-Fatigue and EQ-VAS scores were associated with baseline performance status (FACIT-Fatigue p<0.001; EQ-VAS, p=0.001) and, marginally, with subsequent response to therapy (partial response/stable disease was associated with less fatigue or better health state; FACIT-Fatigue p=0.169; EQ-VAS p=0.033). FACIT-Fatigue and EQ-VAS scores declined across these four cycles (average change from baseline: FACIT-Fatigue = -2.2, EQ-VAS = -5.87) but these changes are smaller than what is considered ‘minimally important’ for these measures. A pattern of decline and recovery coincided with the 4-week on/2-week off periods in each cycle. Average change from baseline in FACIT-Fatigue and EQ-VAS scores did not differ with response to therapy. Conclusions: SU11248 did not cause significant changes in PROs in this group of patients, although FACIT-Fatigue and EQ-VAS scores declined slightly while patients were on treatment and improved while they were off treatment in the first four cycles. These changes were not correlated with tumor response. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Pfizer Pfizer Pfizer