Kim, George P.

We assessed the efficacy and safety of combining bevacizumab with temsirolimus in patients with advanced extra-pancreatic neuroendocrine tumors. This NCI-sponsored multicenter, open-label, phase II study (NCT01010126) enrolled patients with advanced, recurrent, or metastatic extra-pancreatic neuroendocrine tumors. All patients were treated with temsirolimus and bevacizumab until disease progression or unacceptable toxicity. Temsirolimus 25 mg was administered i.v. on days 1, 8, 15, and 22 and bevacizumab 10 mg/kg i.v. on days 1 and 15 of a 4-week cycle. Discontinuation of temsirolimus or bevacizumab did not require discontinuation of the other agent. The primary endpoints were objective response rate and 6-month progression-free survival rate. Fifty-nine patients were enrolled in this study, and 54 were evaluated for efficacy and adverse events. While median progression-free survival was 7.1 months, the median duration of treatment with temsirolimus was 3.9 months and that with bevacizumab was 3.5 months. The objective response rate of combination therapy was 2%, and 6-month progression-free survival was 48%. The most frequently reported grade 3–4 adverse events included fatigue (13%), hypertension (13%), and bleeding (13%). Close to 54% of the patients discontinued treatment due to adverse events, refusal of further treatment, or treatment delays. Three deaths occurred in the study, of which two were due to treatment-related bowel perforations. Given the minimal efficacy and increased toxicity seen with the combination of bevacizumab and temsirolimus, we do not recommend the use of this regimen in patients with advanced extra-pancreatic neuroendocrine tumors.

Abstract Background This North Central Cancer Treatment Group (NCCTG) N064A (Alliance) phase II trial evaluated upfront chemoradiotherapy incorporating the EGFR inhibitor panitumumab, followed by gemcitabine and panitumumab for unresectable, non-metastatic pancreatic cancer. Methods The treatment consisted of fluoropyrimidine and panitumumab given concurrently with radiotherapy followed by gemcitabine and panitumumab for 3 cycles followed by maintenance panitumumab. The primary endpoint was the 12-month overall survival (OS) rate and secondary endpoints included confirmed response rate (RR), OS, progression-free survival (PFS), and adverse events. Enrollment of 50 patients was planned and the study fully accrued. Results Fifty-two patients were enrolled, but only 51 were treated and included in the analysis. The median age of patients was 65 years and 54.9% were women. Twenty-two patients received at least 1 cycle of systemic therapy following radiotherapy, but 29 patients received chemoradiotherapy only without receiving subsequent chemotherapy after completion of chemoradiotherapy. The overall RR was 5.9% (95% CI: 1.2%-16.2%). The 12-month OS rate was 50% (95% CI: 38%-67%) which fell short of the per-protocol goal for success (51.1%). The median PFS was 7.4 months (95% CI: 4.5-8.6) and the median OS was 12.1 months (95% CI 7.9-15.9). Grade 3 or higher adverse events were reported by 88%. Conclusion The combination of panitumumab, chemotherapy, and external beam radiation therapy was associated with very high rates of grades 3-4 toxicities and survival results did not meet the trial’s goal for success. This regimen is not recommended for further study (ClinicalTrials.gov Identifier NCT00601627).

4026 Background: Patients (pts) with locally advanced esophageal or gastroesophageal junction (GEJ) adenocarcinoma commonly receive neoadjuvant chemoradiotherapy (chemo-RT). Despite this approach the rate of recurrence remains high. Given the difficulties of postoperative therapy, the efficacy of extended neoadjuvant therapy was assessed. Methods: Eligibility criteria included T3-4,N0 – Tany,N(+) disease amenable to radiation and surgery. Pts were randomized to either arm A (docetaxel 60 mg/m2 day 1 , oxaliplatin [Oxal] 85 mg/m2 day 1, and capecitabine 1250 mg/m2/day days 1-14 x 2 cycles [DOC] followed by 5-FU 180 mg/m2/day continuous IV through radiation + Oxal 85 mg/m2 days 1,15,29 + 50.4 Gy radiation (chemo-RT)) or arm B (chemo-RT alone). Randomization was stratified by ECOG PS (0/1 vs 2) and stage (II vs III/IVA). Primary endpoint was pathologic complete response (PCR) rate, defined as no gross or microscopic tumor identified in the surgical specimen. Interim analysis assessed efficacy and futility of the experimental intervention. Wilcoxon rank sum and Fisher’s exact tests were used to compare clinical/pathologic factors between arms. Results: Baseline and stratification factors were well balanced between arms. Of 42 pts included in the interim analysis (86% male; age [median 63, range 38-88], 100% PS 0/1; 71% stage III; 55% esophagus, 40% GEJ; 36% measurable disease), 4 and 1 pts in arms A and B, respectively, did not have surgery due to death (A, 2), progressive disease (A, 1), alternative treatment (A, 1) or adverse event (B, 1). Among 21 arm A pts, 21, 20, and 19 pts started 1st cycle of DOC, 2nd cycle of DOC and chemo-RT, respectively. All arm B pts received chemo-RT. 33% (7/21) of arm A and 48% (10/21) of arm B pts achieved PCR (p=0.53). Among pts undergoing surgery, 94% (16/17) and 100% (20/20) of arm A and B pts had complete resection (p=0.46). 38% and 24% of arm A and B pts experienced at least one grade 4+ adverse event at least possibly related to treatment (p=0.51). Conclusions: Extended neoadjuvant therapy in pts with locally advanced esophageal or GEJ adenocarcinoma failed to improve the PCR rate. Follow-up in regard to survival and rate of recurrence is ongoing. Clinical trial information: NCT00938470.

e13052 Background: The combination of GEM and CDDP has shown activity in a variety of cancers, including biliary tract/gallbladder. Preclinical testing shows a potential benefit to the addition of EV. Methods: Using a standard 3+3 design, the MTDs of GEM + EV (Cohort I) and GEM + CDDP + EV (Cohort II) were determined as shown in the table. The MTD was defined as the dose level below the lowest dose that induces a DLT in at least one-third of pts. At the MTD of Cohort II, 10 patients were enrolled with biliary tract/gallbladder cancer (Cohort III). A weekly CBC was obtained. Assessments occurred every 3 weeks and imaging for response at every other cycle. Results: In Cohort I (N=12), no DLT occurred at dose level 0, and in dose level 1, grade 3 thrombocytopenia was found in 2 of 6 pts. The MTD for Cohort I was determined to be dose level 0. Responses were seen in 3 pts: 2 CRs (primary peritoneal, pancreatic) and 1 PR (breast). In Cohort II (N=15) DLTs at dose level 0 were neutropenia and thrombocytopenia in 2 of 3 pts and at dose level -1, thrombocytopenia in 2 of 6 pts. At dose level -2, 1 of 6 pts experienced a DLT (grade 3 thrombocytopenia), establishing this dose level as the MTD. Responses were seen in 2 pts, both PRs (ampullary, pheochromocytoma). All 10 pts have been enrolled in Cohort III with 2 DLTs (neutropenia and thrombocytopenia). Stable disease seen in 5 of 7 evaluable pts. Conclusions: Gem + EV was well tolerated at dose level 0, though dose escalation was limited by thrombocytopenia. GEM + CDDP + EV had DLTs of neutropenia and thrombocytopenia leading to the MTD of dose level of -2. Cohort III is fully accrued and the 2 DLTs are hematologic. [Table: see text]

3640 Background: Prior economic analysis of a 12-gene assay (Oncotype DX), compared with patterns of care reported in the NCCN database of patients with stage II, T3, DNA mismatch repair proficient (MMR-P) colon cancer, predicted that the assay would save medical costs and improve patient well-being (Hornberger et al. Value Health 2012). This study assessed the validity of those findings with actual adjuvant chemotherapy (aCT) recommendations. Methods: Outcomes and costs were estimated for patients with stage II, T3, MMR-P colon cancer using a Markov model. A study of 141 patients from 17 sites in the Mayo Clinic Cancer Research Consortium collected data on aCT recommended before and after knowledge of the 12-gene assay results (Srivastava et al. abstract). Quality-adjusted life years (QALY) and medical resource use after recurrence were computed using guideline-validated state-transition probability estimation methods. Risk of progression and incidence of adverse events with different aCT regimens were based on published literature. Drug and administration costs for aCT were obtained from 2012 Medicare fee schedules. One-way sensitivity analyses were conducted to evaluate parameter influence on economic impact. Results: After receiving the 12-gene assay results, physician recommendations in favor of aCT decreased 22% (95% CI 11%-32%; McNemar test p<0.001) from 73 (52%) to 42 (30%) patients. Oxaliplatin aCT and 5-FU monotherapy recommendations each declined 11%. Average aCT costs decreased $3,228 for drugs, $750 for administration, and $3,168 for adverse events management. Overall, average total direct medical costs decreased $1,683. The net effect on average patient well-being was a gain of 0.102 QALYs. Total change in medical costs is most influenced by the cost of death due to colon cancer, time-preference discount rate, and the change in aCT recommendations. Savings are expected to persist even if the cost of oxaliplatin dropped by >75% due to generic substitution. Conclusions: The 12-gene assayhas been shown to alter aCT recommendations for patients with stage II, T3, MMR-P colon cancer. This study provides real-world confirmation that these aCT changes reduce direct medical costs and improve patient well-being.

3539 Background: Therapy with decitabine and entinostat (ENT: HDAC inhibitor) shows synergistic effect in re-expression of tumor-suppressor genes and growth inhibition in CRC cell lines and in vivo studies. Methods: We conducted a phase II, multi-institutional study of SQ 5-azacitidine (AZA) and oral ENT in mCRC pts. A 28 day cycle included: AZA at 40 mg/m2 d1-5 and 8-10 with ENT 7 mg d3 and 10. Initial eligibility criteria included: ECOG PS 0-1, good end organ function, and biopsiable disease for cohort A (CoA). An interim analysis indicated that toxicity which crossed pre-specified safety boundary was secondary to disease. A 2nd cohort B (CoB) with eligibility restrictions: <2 prior regimens in KRAS-mutated CRC pts, <3 prior regimens if KRAS wild-type, and liver disease limited to <30% of volume was accrued. Serial tumor biopsies and research blood were collected to assess for methylation/expression changes in circulating tumor DNA and biopsies, respectively. The primary endpoint was response as measured by RECIST criteria using a 2-stage Simon design. Results: 47 pts were initially enrolled (24 CoA, 23 CoB). Pts received a median of 2 cycles on both cohorts (1-16 CoA, 2-6 CoB). Pts had a median of 4 prior therapies for CoA (range 2-9) and 3 for CoB (range 2-6). Gr 4 AEs attributable to treatment for CoA included hyperglycemia (1) and hypokalemia (1); other common Gr 3 AEs included anemia (3), decreased lymphocytes (7), fatigue (3), and nausea (3). CoB pts experienced grade 3 chest pain (1), neutropenia (2), leucopenia (2), urinary tract obstruction (1), and hypophosphatemia (1). No responses have been observed. Results of translational objectives will be presented at the meeting. Conclusions: SQ AZA and ENT therapy does not have clinical activity as defined by confirmed response in aCRC. Follow-up for survival, response to subsequent therapy, and correlative analysis are ongoing. Supported in part by N01-CM-2011-00099. Clinical trial information: NCT01105377. [Table: see text]

4038 Background: GEM has served as the chemotherapy platform for most phase III clinical trials in APC, inc. CALGB 80303 (GEM +/- BEV). However, GEM-based combination regimens may confer superior outcomes in select pts and represent a preferred backbone in clinical trial design testing targeted agents. Methods: Data was pooled from 5 phase II trials evaluating GEM-based cytotoxic doublets plus BEV in APC. 1o endpoint was OS. 2o endpoints included ORR, CA19-9 response, and adverse events (AEs). Kaplan-Meier methods estimated time-to-event endpoints. The Cox proportional hazard model estimated univariate hazard ratios (HR) of death. Results: Of 261 pts, 90.7% were Caucasian, 95.4% had an ECOG PS 0-1, and 91.6% had metastatic disease. Median age = 60y. Pooled OS data (in mos), stratified for PS and stage, is shown in the table. ORR across all trials: CR 1.6%, PR 22.9%, SD 50.8%, PD 20.2%, NA 4.7%. HR for pts who achieved disease control (CR/PR/SD) was 0.35 vs. those with PD (95% CI 0.23-0.54, p<0.001). 76.5% of pts had elevated baseline CA19-9; of these, 62% achieved ≥50% reduction (HR 0.50; 95% CI 0.34-0.73, p<0.001). BEV-related AEs ≥grade 3: HTN (10.6%), hemorrhage (9.5%), VTE (10.1%), cardiac events (3.4%), and bowel perforation (2.2%). Median OS in pts with grade 3-4 HTN was 13.4 mos vs. 9.8 mos in those without (HR 0.77; 95% CI 0.48-1.24, p=0.29). Conclusions: Recognizing the limitations of single-arm phase II trial design and cross-study comparisons, these results compare favorably to those from CALGB 80303. The standard paradigm of GEM +/- drug X in clinical trial development for APC needs to be reconsidered. Based on our data as well as the recent phase III FOLFIRINOX study, building on more intensive combination chemo regimens in future trials may represent a better strategy, especially for pts with good PS. [Table: see text]

Abstract Lessons Learned Dual epidermal growth factor receptor (EGFR)-directed therapy with erlotinib and panitumumab in combination with gemcitabine was superior to gemcitabine and erlotinib, but the clinical relevance is uncertain given the limited role of gemcitabine monotherapy. A significantly longer overall survival was observed in patients receiving the dual EGFR-directed therapy. The dual EGFR-directed therapy resulted in increased toxicity. Background Gemcitabine is active in patients with advanced pancreatic adenocarcinoma. The combination of erlotinib, an oral epidermal growth factor receptor (EGFR) inhibitor, and gemcitabine was shown to modestly prolong overall survival when compared with gemcitabine alone. The North Central Cancer Treatment Group (now part of Alliance for Clinical Trials in Oncology) trial N064B compared gemcitabine plus erlotinib versus gemcitabine plus combined EGFR inhibition with erlotinib and panitumumab. Methods Eligible patients with metastatic adenocarcinoma of the pancreas were randomized to either gemcitabine 1,000 mg/m2 on days 1, 8, and 15 of a 28-day cycle with erlotinib 100 mg p.o. daily (Arm A) or the same combination with the addition of panitumumab 4 mg/kg on days 1 and 15 of a 28-day cycle (Arm B). The primary endpoint of the trial was overall survival. Secondary endpoints included progression-free survival, the confirmed response rate, and toxicity. Comparison between arms for the primary endpoint was done with a one-sided log-rank test, and a p value less than .20 was considered statistically significant. Response rate comparison was done with Fisher's exact test. All other reported p values are two-sided. Results A total of 92 patients were randomized, 46 to each arm. The median overall survival was 4.2 months in Arm A and 8.3 months in Arm B (hazard ratio, 0.817; 95% confidence interval [CI], 0.530–1.260; p = .1792). The progression-free survival was 2.0 months in Arm A and 3.6 months in Arm B (hazard ratio, 0.843; 95% CI, 0.555–1.280; p = .4190). A partial confirmed response was seen in 8.7% of patients on Arm A and 6.5% on Arm B (p = .9999). No patients had a complete response. Grade 3 and higher nonhematologic toxicities were more common in patients on Arm B compared with those on Arm A (82.6% vs. 52.2%; p = .0018). Conclusion Dual EGFR-directed therapy resulted in a significant prolongation of overall survival in patients with advanced adenocarcinoma of the pancreas but was associated with substantially increased toxicities. Dual EGFR-directed therapy in combination with gemcitabine alone cannot be recommended for further study, as single-agent gemcitabine is no longer considered an appropriate therapy for otherwise fit patients with metastatic pancreatic cancer.