Hurwitz, Herbert I.

Abstract Purpose: The purpose of this study was to evaluate the safety and efficacy of ontuxizumab (MORAb-004), a monoclonal antibody that interferes with endosialin (tumor endothelial marker-1) function, in patients with chemorefractory metastatic colorectal cancer and to identify a responsive patient population based on biomarkers. Experimental Design: This was a randomized, double-blind, placebo-controlled, phase II study. Patients were randomly assigned in a 2:1 ratio to receive weekly intravenous ontuxizumab (8 mg/kg) or placebo plus best supportive care until progression or unacceptable toxicity. Tissue and blood biomarkers were evaluated for their ability to identify a patient population that was responsive to ontuxizumab. Results: A total of 126 patients were enrolled. No significant difference between the ontuxizumab and placebo groups was evident for the primary endpoint of progression-free survival (PFS), with a median PFS of 8.1 weeks in each group (HR, 1.13; 95% confidence interval, 0.76–1.67; P = 0.53). There were no significant differences between groups for overall survival (OS) or overall response rate (ORR). The most common treatment-emergent adverse events (TEAEs) in the ontuxizumab group (vs. the placebo group, respectively) were fatigue (53.7% vs. 47.5%), nausea (39.0% vs. 35.0%), decreased appetite (34.1% vs. 27.5%), and constipation (28.0% vs. 32.5%). The most common grade 3/4 TEAE in the ontuxizumab group versus placebo was back pain (11.0% vs. 0%). No single biomarker clearly identified patients responsive to ontuxizumab. Conclusions: No benefit with ontuxizumab monotherapy compared with placebo for clinical response parameters of PFS, OS, or ORR was demonstrated. Ontuxizumab was well tolerated. Clin Cancer Res; 24(2); 316–25. ©2017 AACR.

Purpose Factors contributing to early mortality after initiation of treatment of metastatic colorectal cancer are poorly understood. Materials and Methods Data from 22,654 patients enrolled in 28 randomized phase III trials contained in the ARCAD (Aide et Recherche en Cancérologie Digestive) database were pooled. Multivariable logistic regression models for 30-, 60-, and 90-day mortality were constructed, including clinically and statistically significant patient and disease factors and interaction terms. A calculator (nomogram) for 90-day mortality was developed and validated internally using bootstrapping methods and externally using a 10% random holdout sample from each trial. The impact of early progression on the likelihood of survival to 90 days was examined with time-dependent Cox proportional hazards models. Results Mortality rates were 1.4% at 30 days, 3.4% at 60 days, and 5.5% at 90 days. Among baseline factors, advanced age, lower body mass index, poorer performance status, increased number of metastatic sites, BRAF mutant status, and several laboratory parameters were associated with increased likelihood of early mortality. A multivariable model for 90-day mortality showed strong internal discrimination (C-index, 0.77) and good calibration across risk groups as well as accurate predictions in the external validation set, both overall and within patient subgroups. Conclusion A validated clinical nomogram has been developed to quantify the risk of early death for individual patients during initial treatment of metastatic colorectal cancer. This tool may be used for patient eligibility assessment or risk stratification in future clinical trials and to identify patients requiring more or less aggressive therapy and additional supportive measures during and after treatment.

348 Background: Patients (pts) with mUC have few treatment options beyond the second-line setting. HER2 gene amplification has been reported in a minority of pts with UC, but there have been anecdotal reports of the activity of HER2-targeted agents. MyPathway is a multi-basket study evaluating the efficacy and safety of targeted therapies in non-indicated tumor types harboring relevant molecular alterations. We present preliminary data for pts with HER2-positive mUC receiving HER2-targeted treatment with pertuzumab + trastuzumab. Methods: MyPathway (NCT02091141) is an open-label, multicenter, phase IIA study. Pts in this subset analysis had refractory mUC with HER2 amplification or putative activating mutations by gene sequencing, FISH, or IHC. Pts received standard doses of pertuzumab + trastuzumab without chemotherapy until disease progression or unacceptable toxicity. The primary endpoint is investigator-assessed overall response rate (RECIST v1.1). Results: As of July 31, 2016, 12 pts with platinum-resistant HER2-positive mUC (HER2-amplified, n=9; HER2-mutated, n=3) have been enrolled. At a median follow-up of 5.4 (range 0.9–14.5) mos, 1 pt had complete response (CR, ongoing at 12.5 mos), 2 had partial responses (PR; duration of response, 3.7 and 5.5 mos), and 2 had stable disease (SD) for >4 mos (Table). Safety was consistent with the product labels. Conclusions: Preliminary results indicate that the combination of pertuzumab + trastuzumab has activity in previously treated HER2-amplified mUC, including a durable CR in a pt with peritoneal metastases. Accrual to MyPathway is ongoing. Clinical trial information: NCT02091141. [Table: see text]

514 Background: Randomized trials and OCSs have demonstrated that BV treatment in 1st-line (1L), in 2L, and across multiple lines is associated with longer survival in patients (pts) with mCRC. This analysis was aimed at comparing the effectiveness of BV after 1st disease progression (PD) between male and female mCRC pts who received 1L BV-containing therapy in a real-world setting. Methods: ARIES is a large, prospective OCS that enrolled pts who received BV and chemotherapy (CT) for 1L mCRC. Post-PD effectiveness was assessed for men and women characterizing BV use by cumulative and dichotomous approaches. The primary analysis treated BV exposure as cumulative BV doses after 1st PD and post-progression overall survival (ppOS) as the time from 1st PD to death. A time-dependent Cox regression model was fitted to assess the effect of cumulative BV exposure on ppOS, while controlling for potential confounders. A dichotomous secondary analysis characterized BV exposure as receipt of CT + BV (BBP) or CT alone (No BBP) within 2 months after PD and ppOS as time from 1st PD + 2 months to death. Results: Among the 1,550 1L mCRC pts enrolled, 1,199 (532 women) had PD. In the primary analysis, hazard ratios (HRs) for ppOS decreased, on average, by 1.2% with each additional BV dose. When stratified by sex, the average risk reduction per BV dose over 15 doses was 1.8% in women and 0.7% in men. In the secondary analysis that included 331 women (BBP, 180; No BBP, 151) and 417 men (BBP, 245, No BBP, 172) who received BV ± CT within 2 months post-PD, the HRs for ppOS with BBP treatment were 0.46 (95% CI, 0.35–0.59) in women and 0.52 (95% CI, 0.41–0.67) in men. Statistical interaction tests for differences in the effectiveness of BV between men and women were negative for primary and secondary analyses (P of 0.58 and 0.77). Protocol-specified adverse events occurred in 17.8% of women and 10.2% of men in the BBP population; this difference was largely related to rates of hypertension (8.3% vs 2.4%, respectively). Conclusions: In ARIES, the effectiveness of BV after first PD was not statistically different between women and men with mCRC. Clinical trial information: NCT00388206.

702 Background: Median overall survival (OS) in mCRC has significantly improved over the past 20 yrs, but the observed range of OS in pts remains wide; a large percentage of pts have OS <1 yr or >4 yrs. ARIES was a prospective OCS conducted from 2006–2012 that evaluated outcomes in pts receiving BV + chemotherapy (CT) for mCRC in general clinical practice. The objective of this analysis is to examine clinical characteristics of pts with long vs short OS. Methods: This analysis included 1,417/1,550 first-line (1L) BV-treated mCRC pts who died or had complete follow-up on study. Long OS was defined as OS within the upper quartile of the analysis population (range 42–67 mos); short OS was defined as OS within the lower quartile (range 0.3–12 mos). Progression-free survival (PFS) was estimated using Kaplan-Meier methods. Pt and disease characteristics and treatment patterns were described using summary statistics. Results: Pt and disease characteristics are shown in the Table. Median PFS was 22.3 mos (95% CI, 19.9–23.3) vs. 4.9 mos (95% CI, 4.6–5.4), in the long-OS vs. short-OS groups. More pts with long OS received any second-line (2L) therapy (71% vs. 46%), and were exposed to 5-fluorouracil, oxaliplatin, and irinotecan throughout the course of their disease (53% vs. 32%) compared with pts with short OS. KRAS/BRAF mutation status was not collected. Conclusions: Pts with long OS had better baseline performance status, primary tumors more likely to have been resected, and were more likely to have received 2L CT. Additional analyses of detailed treatment patterns and safety are ongoing. Clinical trial information: NCT00388206. [Table: see text]

653 Background: Next-generation sequencing often reveals potentially actionable molecular alterations; however, data on approved targeted therapies in non-indicated tumors are limited. MyPathway (NCT02091141) evaluates agents targeting the HER2, EGFR, BRAF, or Hedgehog (Hh) pathways in tumors for which these therapies are not currently indicated. Here, we present early response data for patients with GI tumors. Methods: Eligible patients had metastatic tumors with potentially actionable genomic alterations, identified by a CLIA-certified lab, and progression on standard therapy. Based on the identified alteration, patients received standard doses of trastuzumab + pertuzumab (HER2), erlotinib (EGFR), vemurafenib (BRAF), or vismodegib (Hh). Response was evaluated by the investigator using RECIST v1.1. Results: As of Aug 21, 2015, 96 patients had enrolled, 36 of whom (38%) had GI tumors with the following alterations: HER2 (n=28 [22 amplifications, 5 activating mutations, 1 both]), BRAF (n=4), Hh (n=2 [2 PTCH-1 mutations]), and EGFR (n=2). Patients had a median of 4 (range, 1–8) prior lines of therapy. Tumor types and interim best response data are shown below. Among all evaluable patients with GI tumors (n=26), 5 have had a PR to targeted therapy (duration 3–10+ months). Conclusions: Targetable molecular alterations were found in a variety of GI tumors, resulting in clinical benefit from targeted treatments that would not have otherwise been realized. These early results support this molecular testing strategy. Accrual to the trial continues; based on activity observed, the HER2-positive colorectal cancer cohort will be expanded to ≥30 patients. Additional data will be presented at the meeting. Clinical trial information: NCT02091141. [Table: see text]

535 Background: Prior ARIES analyses showed that BV-treated mCRC patients (pts) receiving chemotherapy (CT)/biologics + BV within 2 months (mo) after 1st progressive disease (PD) had longer post-progression survival (PPS) than pts receiving only CT/biologics. The present analysis evaluated whether this effect of BV was consistent when used with common 2L CT regimens— irinotecan- (iri-) and oxaliplatin- (ox-) based—in mCRC pts exposed to 1L BV in ARIES. Methods: ARIES enrolled mCRC pts receiving 1L CT + BV. No tx regimens or assessments were protocol specified. This analysis evaluated 1L BV-treated mCRC pts who had PD, survived ≥2 mo after PD, and received 2L iri- or ox-based tx. PPS was estimated by Kaplan-Meier methods. Cox regression was used to estimate hazard ratios (HRs), while adjusting for covariates (eg, 1L time to progression). Results: Of 1550 1L pts in ARIES, 1074 had 1st PD and survived ≥2 mo after PD. Of these 1074, 390 and 114 received 2L iri- and ox-based tx, respectively, ± BV ( table ). Baseline characteristics were generally similar between groups. The incidence of targeted adverse events (TAEs) was as expected and similar between the BV and No BV groups over time. In pts receiving 2L iri- or ox-based CT tx, PPS in BV-treated pts was longer compared to those not on BV. Analyses may be limited by small pt numbers in some groups. Conclusions: Consistent with prior ARIES analyses, the continued use of BV after 1st PD was associated with prolonged PPS regardless of the 2L CT backbone used. [Table: see text]

Purpose In recent retrospective analyses of early-stage colorectal cancer (CRC), low and high body mass index (BMI) scores were associated with worsened outcomes. Whether BMI is a prognostic or predictive factor in metastatic CRC (mCRC) is unclear. Patients and Methods Individual data from 21,149 patients enrolled onto 25 first-line mCRC trials during 1997 to 2012 were pooled. We assessed both prognostic and predictive effects of BMI on overall survival and progression-free survival, and we accounted for patient and tumor characteristics and therapy type (targeted v nontargeted). Results BMI was prognostic for overall survival (P < .001) and progression-free survival (P < .001), with an L-shaped pattern. That is, risk of progression and/or death was greatest for low BMI; risk decreased as BMI increased to approximately 28 kg/m 2 , and then it plateaued. Relative to obese patients, patients with a BMI of 18.5 kg/m 2 had a 27% increased risk of having a PFS event (95% CI, 20% to 34%) and a 50% increased risk of death (95% CI, 43% to 56%). Low BMI was associated with poorer survival for men than women (interaction P < .001). BMI was not predictive of treatment effect. Conclusion Low BMI is associated with an increased risk of progression and death among the patients enrolled on the mCRC trials, with no increased risk for elevated BMI, in contrast to the adjuvant setting. Possible explanations include negative effects related to cancer cachexia in patients with low BMI, increased drug delivery or selection bias in patients with high BMI, and potential for an interaction between BMI and molecular signaling pathways.