Alberts, Steven R.

LBA4004 Background: Gemcitabine (GEM) is the cornerstone of treatment of metastatic pancreatic cancer (PANCA). FDR GEM or GEMOX are promising, but have yet to convincingly demonstrate a survival advantage over GEM alone. E6201 compares overall survival (OS) of standard GEM 1000 mg/m2/30 min wkly ×7 over 56 days then wkly ×3 q28 d (ARM A) vs. FDR GEM 1500 mg/m2/150 min wkly ×3 q28 days (ARM B) or GEM 1000 mg/m2/100-min/d1 + oxaliplatin 100 mg/m2/d2 q14d (ARM C). Secondary endpoints are the comparison of the experimental regimens, toxicity, response, patterns of failure, progression-free survival and quality-of-life. Methods: This multi-institutional trial included patients (pts) with measurable and non-measurable advanced, unresectable PAN CA, normal organ function and PS 0–2. Pts were chemonaive, although prior adjuvant radiosensitizing 5FU was permitted. Pts were stratified by PS 0–1 vs 2 and locally advanced vs metastatic disease The study was designed to detect a 33% difference in median survival (hazard ratio 1.33) with 81% power while maintaining a significance level of 2.5% in a two-sided test for each of the two primary comparisons, assuming exponential failure and median survival of 6 mo for Arm A and 8 mo for Arm B and C (N = 750 eligible). Results: Accrual started in 3/03 and completed in 3/05. Median follow up is 5.8 mo. 833 pts (53% men; 88% PS 0–1; 88% metastatic), were randomized with 280, 277 and 276 pts in Arms A, B and C. The third interim analysis was conducted with 89.5% information on 3/2006. The predominant toxicity, available for 758 pts, was grade 3/4 myelosuppression and fatigue. Two deaths from ARDS and infection occurred. Median OS for ARMS A, B, and C are 4.96, 6.01 and 6.47 months, respectively. Hazard ratio A vs B is 1.21 with stratified log rank of 0.053 and for A vs C is 1.22 with stratified log rank of 0.045, neither statistically significant. Conclusion: E6201 final OS results will be available in June, 2006. [Table: see text] [Table: see text]

3525 Background: The prognosis for patients with hepatic metastases from M-CRC can be poor. However, surgery followed by HAI FUDR plus systemic (SYS) 5-FU improves 5-yr survival rates. Oxaliplatin (OXAL) combined with capecitabine (CAPE) has demonstrated activity in advanced CRC. We report early results of an analysis of SYS OXAL plus CAPE, alternating with HAI FUDR. The primary endpoint is 2-yr survival (2YS). Methods: Patients with M-CRC liver lesions amenable to resection ± ablation were eligible. HAI + SYS therapy was initiated following metastasectomy. Alternating courses of HAI consisted of 0.2 mg/m2/d FUDR and dexamethasone, d1–14 weeks 1 & 2. SYS therapy included 130 mg/m2 OXAL d1, with CAPE at 1000 mg/m2 p.o. BID, d1–14, weeks 4 & 5. Two additional 3-wk courses of SYS therapy were given. CAPE was reduced to 850 mg/m2/BID after interim review of toxicity (GI Cancer Symposium 2004). Patient Characteristics: 54 of 70 patients were able to initiate HAI FUDR + SYS. 52% had a solitary met and 24% presented with bilobar mets. Results: Patients completed median of 6 cycles (range 1 - 6). Reasons for discontinuation included: refusal/toxicity (10), completed per protocol (32), recurrence (4), and medical/other (3). No post-operative or treatment related deaths were reported. 69% (31/45) of evaluable patients are alive with a minimum 18 mos of follow-up. 6 deaths occurred in less than 2 yrs. 44% (20/45) have recurred, with 40% (8/20) having liver involvement. Median time-to-progression is 32 mos with an estimated 2YS rate of 86% (95% CI 76–97%). Conclusions: The combination of HAI FUDR and SYS therapy appears to improve outcome following resection of hepatic CRC-M. Updated follow-up is necessary to solidify the primary endpoint of 2YS. Supported by NIH Grant CA25224–18, Sanofi-Synthelabo, and Roche Laboratories, Inc. Maximum Severity, Grade 3+ (N=54) [Table: see text] [Table: see text]

3509 Background: FOLFIRI or FOLFOX are 1st-line treatments (Rx) for MCRC. Cetuximab is an IgG1 Mab that targets the epidermal growth factor receptor (EGFR) and is approved as monotherapy or in combination with irinotecan in irinotecan-refractory, EGFR + pts with MCRC. CALGB 80203 randomized untreated MCRC pts to FOLFOX or FOLFIRI ± cetuximab (independent of EGFR status.) Methods: Pts with performance status 0–1 with tumor blocks available for EGFR analysis received either irinotecan 180 mg/m2 over 1.5 hours (h) or oxaliplatin 85 mg/m2 over 2h combined with LV 400 mg/m2 over 2h and 5FU 400 mg/m2 bolus, then 46–48h CI 5FU 2400 mg/m2 q o w. Cetuximab dose: 400 mg/m2 loading dose, then 250 mg/m2 qw. Rx continued until progression or toxicity; subsequent Rx was not mandated although information was collected on such rx. Accrual goal was 2200 pts with intended 1° endpt of overall survival (OS). 80203 closed administratively in 1/05 (due to slow accrual) with 238 pts accrued. 2° endpts of response rate (RR), progression free survival (PFS), duration of R and toxicity are now able to be analyzed. Results: Accrual: FOLFIRI (A) - 61; FOLFIRI + cetuximab (B) - 59: FOLFOX (C) - 60; FOLFOX + cetuximab (D) - 58; approx median follow-up (f/u) is 12 months. RR (CR + PR, not all yet confirmed): A - 34%; B - 42%; C - 32%; D - 55%. RR was similar in the FOLFIRI or FOLFOX arms (A+B v. C+D; 38% v. 43%, p=0.44; chi-square) while C225 containing arms (B+D) v. non-C225 arms (A+C) had a superior RR (49% v. 33%; p=0.014, chi-square) It is too early to tell if there are differences in PFS, duration of response or OS. No significant differences in gr III diarrhea or any gr IV toxicities were seen. Conclusions: These results suggest that FOLFIRI and FOLFOX are similar in efficacy for pts with untreated MCRC and that adding cetuximab to either in1st-line Rx appears to increase response rates. PFS and duration of response do not appear different at this analysis. Further f/u and an analysis of prospective companion correlative studies may help to further clarify these results. [Table: see text]

3503 Background: The association between race & toxicity or response to systemic chemotherapy is poorly understood. We correlated relevent polymorphisms with toxicity & outcome data in AA & C patients (Pts) enrolled in N9741, a large randomized MCRC trial. Methods: Toxicity, response rate (RR), time to progression (TTP), overall survival (OS), & dose intensity (DI) were examined as a function of race in 1412 Pts enrolled on IFL, both full and reduced dose, FOLFOX, or IROX including 486 Pts with pharmacogenomic data. Accrual by race permitted comparison of C (n=1297) to AA (n=112). Results: C & AA were similar in disease extent, PS, gender, prior adjuvant treatment, and DI at cycles 1, 3, 6, or 12. The impact of race on RR, toxicity & the distribution of four relevent drug metabolism genotypes are in the table . AA had lower RR overall & in each treatment arm. Lower toxicity rates were seen in AA Pts, mainly due to less diarrhea, as measured by both CTC V2 & patient reported outcome data. These relationships were maintained in multivariate models adjusting for arm, age, gender, & PS. In these multivariate models, the odds ratio between RR and race was 1.72 (p=0.012) (29% AA vs 41% C) & for severe toxicity the odds ratio was 1.76 (p=0.006) (34% AA vs 48% C). Overall, race was not a significant predictor of TTP or OS (p > 0.50 for each). The hazard ratio comparing FOLFOX to IFL for C was 0.67 and for AA was 0.55. TTP for FOLFOX was superior to both IFL and IROX for both C & AA. Significant differences in pharmacogenetic variants were observed between C & AA, although the sample size for investigating the three-way combination of Rx, race, & pharmacogenomics is too small (36 AA) to draw definitive conclusions. Conclusions: It appears that AA have less toxicity & a lower RR than C when treated with standard MCRC regimens. Different frequencies of polymorphisms in genes relevent to drug metabolism may help explain these clinical differences. [Table: see text] [Table: see text]

6517 Background: In NCCTG CTs a subset of AEs are assessed at each patient (pt) evaluation based on the known safety profile of agents(s). The NCCTG routinely pre-fills the “known” AE list onto CT Case Report Forms (CRFs). Newly identified AEs may expand the AE assessment list for ongoing CTs. Our survey of NCCTG AE data (JCO 2005), demonstrated that 85% of AEs reported were pre-filled on CRFs, of which, 83% did not actually occur (Grade 0). Extending this work, we evaluated the influence of pre-filling AEs on CRFs, relative to the final AE rates reported. Methods: Our non-random sample contains 507,899 AEs collected from 1/99–6/06 on 74 NCCTG CTs, 13 of which had AEs added to the CRF pre-fill list during the CT (2,604 pts, 3 Ph I/II, 8 Ph II, 2 Ph III, 9 investigational agents). Results: An average of 2.8 AEs (range 1–6) were added to CRFs for ongoing CTs, primarily for Oxaliplatin induced AEs. 58% (21/36) of AEs added during a CT were not reported prior to the addition, 22% (8) were not reported afterwards. 5 CTs had significantly higher AE rates (p<0.01) after expanding the AE list, most notably for required blood chemistries (SGOT/alk phos/creatinine/bilirubin 14.2 vs 0.72%). Overall, the same AEs were 4-fold (range 0–25) as likely to be reported when pre-filled on the CRF. Regardless of pre-filling, only 6% of the newly required AEs were Gr 3+. Conclusions: Our data suggest a significant difference between the AE rates reported if included in the CT CRF assessment list. This may significantly influence the reported results of a CT, explaining differential AE rates reported across CTs of the same agent(s). A prospective study is planned to formally evaluate this observation. Supported by NIH Grant CA25224. No significant financial relationships to disclose.

4578 Background: Gemcitabine is commonly used in patients with cholangiocarcinoma with a response rate of 20–30% and median overall survival of 6–10 months. Pemetrexed’s mechanism of action and tolerability in patients with hepatic dysfunction makes it a potential agent for cholangiocarcinoma. Methods: Patients with unresectable, previously untreated biliary tract cancers were eligible for participation. Patients received pemetrexed 500 mg/m2 IV over 10 minutes and gemcitabine 800 mg/m2 IV at 10 mg/m2/minute on days 1 and 15 of an every 4 week schedule with vitamin B12 and folate supplementation. The primary end-point is 6-month survival with a planned accrual of 59 patients. Results: 58 eligible patients are included in this analysis. 93% had metastatic disease. Median age was 61 (range: 40 - 81). Median follow-up was 6.5 months (range: 3.3 - 23.2). Median of 3 cycles of treatment was given (range: 1 - 10). Reasons for stopping treatment included disease progression (57%), adverse events (20%), refusal (17%), death on- study (4%), and other medical problems (2%). 6-month survival was 52% (95% CI: 40 - 68%). Median survival was 6.3 months (95% CI: 5.4 - 8.0 months) and median time-to-progression was 3.8 months (2.4 - 5.0). 46 of 58 patients (79%) experienced at least one grade 3+ AE (at least possible attribution), and 26 patients (45%) experienced at least one grade 4 AE (at least possible attribution), most of which were due to grade 4 neutropenia. Conclusions: This study shows similar results to what would be expected with gemcitabine alone. The addition of pemetrexed, as with other agents, has not significantly enhanced the activity of gemcitabine. Supported by NIH Grant CA25224- 18. [Table: see text] No significant financial relationships to disclose.

4057 Background: The prognosis for patients with hepatic metastases from M-CRC can be poor. However, surgery followed by HAI FUDR plus systemic (SYS) 5-FU improves 5-yr survival. Dual therapy OXAL+CAPE has demonstrated activity in advanced CRC. We report final results of an analysis of SYS OXAL+CAPE, alternating with HAI FUDR. The primary endpoint is 2-yr survival (2YS), with 36 of 45 patients surviving 2 yrs as evidence of promising efficacy. Methods: Patients with M-CRC liver lesions amenable to resection ± ablation were eligible. Prior adjuvant chemotherapy for completely resected primary was allowed. HAI+SYS therapy was initiated 21–56 days post-metastasectomy. Four alternating courses of HAI consisted of 0.2 mg/m2/d FUDR and dexamethasone, d1–14 wks 1&2. SYS included 130 mg/m2 OXAL d1, with CAPE at 1,000 mg/m2 po BID, d1–14, wks 4&5. Two additional 3-wk courses of SYS were given. CAPE was reduced to 850 mg/m2/BID after interim review of toxicity. Results: 54 of 73 eligible patients initiated HAI FUDR + SYS. 52% had a solitary met and 24% presented with bilobar mets. Patients completed median of 6 cycles (range 1–6). Reasons for discontinuation included: refusal/toxicity (10), completed per protocol (32), recurrence (4), and medical/other (3). No HAI+SYS related deaths occurred. Median follow-up on the 42 survivors is 28 months (range 7–51). 6 deaths occurred within 2 yrs. 48% (26/54) have recurred; 42% (11/26) with liver involvement. Median time-to-progression is 30 months. The estimated 2YS rate is 88% (95% CI 80–98%) and median overall survival is 46 months (95% CI 41.3-NA). Conclusions: The combination of HAI FUDR and SYS therapy appears to improve outcome following resection of hepatic CRC-M. A 2YS of 88% exceeds our preplanned level of success, supporting the use of this combination in the ongoing NSABP trial C-09. Supported by NIH Grant CA25224–18, Sanofi-Synthelabo, and Roche Laboratories, Inc. No significant financial relationships to disclose.

Background: Bevacizumab (BEV), a monoclonal antibody against vascular endothelial growth factor-A (VEGF-A), is a standard component of medical therapy of metastatic colorectal cancer (mCRC). Activation of alternative angiogenesis pathways has been implicated in resistance to BEV. This phase II study examines the activity of combined vertical blockade of VEGF signaling with sorafenib and BEV as salvage therapy in patients with progressive disease (PD) on all standard therapy in mCRC. Methods: mCRC patients with documented PD on standard therapy, received sorafenib (200 mg orally twice daily, days 1–5 and 8–12) and BEV (5 mg/kg intravenously, day 1) every 2 weeks. Primary endpoint was 3-month progression-free survival (PFS) rate and secondary endpoints were overall survival (OS), response rate (RR), safety, and feasibility. Results: Of the 83 patients enrolled, 79 were evaluable. Of these, 42 (53%) were progression-free at 3 months. Median PFS was 3.5 months and median OS was 8.3 months. One patient had a partial response and 50 patients (63.3%) had at least one stable tumor assessment. Of 79 evaluable patients, 54 (68%) experienced grade 3/4 adverse events (AEs) at least possibly related to treatment. Most frequent grade 3/4 AEs were: fatigue (24.1%), hypertension (16.5%), elevated lipase (8.9%), hand-foot skin reaction (8.9%), diarrhea (7.6%), and proteinuria (7.6%). Reasons for treatment discontinuation were PD (72%), AEs (18%), patient refusal (8%), physician decision (1%), and death (1%). Conclusions: The combination of BEV and sorafenib as salvage therapy in heavily pretreated mCRC patients is tolerable and manageable, with evidence of promising activity. ClinicalTrials.gov identifier: NCT00826540, URL: http://clinicaltrials.gov/ct2/show/NCT00826540

PURPOSE The microsatellite instability (MSI) or deficient mismatch repair (dMMR) phenotype is usually regarded as a single biologic entity, given the absence of comparative analyses regarding prognosis and response to chemotherapy between sporadic and familial dMMR cancers. PATIENTS AND METHODS Patients with stage III colon cancers were randomly assigned to FOLFOX (leucovorin, fluorouracil, and oxaliplatin) with or without cetuximab in 2 large adjuvant phase III trials (N = 5,577). Among patients with MSI and KRAS exon 2 wild-type (WT) tumors, the prognostic and predictive impacts of sporadic versus familial dMMR cancers and BRAF V600E mutational status were determined. Multivariable Cox proportional hazards models were used to assess disease-free survival (DFS) by treatment arm, adjusting for age, sex, tumor grade, Eastern Cooperative Oncology Group performance status, pT/pN stage, and primary tumor location. RESULTS Among patients with MSI status with complete data for dMMR mechanism analysis (n = 354), 255 (72%) had sporadic ( BRAF mutation and/or MLH1 methylation) and 99 (28%) had familial tumors ( BRAF WT and unmethylated MLH1 or loss of MSH2/MSH6/PMS2 protein expression). A large proportion of dMMR sporadic tumors were mutated for BRAF (n = 200). In patients treated with FOLFOX, DFS did not differ statistically by dMMR mechanism, whereas in patients treated with FOLFOX plus cetuximab, those with sporadic tumors had worse DFS than those with familial cancers (multivariable hazard ratio, 2.69; 95% CI, 1.02 to 7.08; P = .04). Considering the predictive utility, the interaction between treatment and dMMR mechanism was significant ( P = .03). Furthermore, a nonsignificant trend toward a deleterious effect of adding cetuximab to FOLFOX was observed in patients with BRAF-mutant but not BRAF WT tumors. CONCLUSION The addition of cetuximab to adjuvant FOLFOX was associated with shorter DFS in patients with sporadic dMMR colon cancer. Additional studies are needed to validate these results in metastatic disease.

TPS594 Background: Effective treatment options are very limited for patients with advanced refractory biliary tract cancer (BTC). Fluoropyrimidine-based chemotherapy regimen such as 5-fluorouracil and irinotecan are frequently utilized for these patients after first-line therapy despite lack of FDA approval. Trifluridine/tipiracil (FTD/TPI) is a novel oral nucleoside with antitumor activity in both fluoropyrimidine sensitive and resistant tumors due to its unique mechanisms of action. Given early toxicity and efficacy data from our previous study on single-agent trifluridine/tipiracil (FTD/TPI) in advanced BTC, the clinical evaluation of its combination with irinotecan represents a rational approach for the treatment of advanced refractory BTC. Methods: This is a single-arm phase II trial with a two-stage design to assess the efficacy of trifluridine/tipiracil (FTD/TPI) and irinotecan in advanced refractory BTC. Key eligibility criteria include histologically confirmed advanced, unresectable BTC who have progressed on at least one line of systemic therapy and have measurable disease per RECIST v1.1. Target accrual is 25. Treatment includes trifluridine/tipiracil (FTD/TPI) 25 mg/m2 on days 1-5 and irinotecan 180 mg/m2 on day 1 in 14-day cycles. Patients will be evaluated for response every 4 cycles and in the absence of disease progression, therapy may be given up to 2 years. The primary end point is the progression-free survival rate at 16 weeks. Secondary endpoints include overall response rate, disease control rate, progression-free survival, overall survival, and incidence of adverse events. Correlative biomarker studies include evaluations of circulating tumor DNA and circulating tumor cells at baseline, after 4 cycles and at progression; and development of patient-derived tumor organoids from pre-treatment biopsies for parallel treatments. This study was approved and funded in part by the National Comprehensive Cancer Network (NCCN) Oncology Research Program from general research support provided by Taiho Oncology, Inc. Clinical trial information: NCT 04072445.