Abstract P5-21-32: AZD5363 in combination with fulvestrant in AKT1-mutant ER-positive metastatic breast cancer

Background: E17K is the most common activating AKT1 mutation and was shown to be a therapeutic target in this multipart Phase 1 study of AZD5363 (NCT01226316), an oral and selective pan-AKT kinase inhibitor, in patients (pts) with AKT1-mutant (AKT1m) advanced solid tumors. In heavily pretreated AKT1m (E17K) ER+ metastatic breast cancer (MBC) pts, monotherapy achieved an objective response rate (ORR) of 20% and a median progression-free survival of 5.5 months (95% CI, 2.9−6.9). Suppression of PI3K-AKT signaling results in induction of ER-dependent transcription, potentially limiting the response to single-agent PI3K/AKT inhibitors. We explored the hypothesis that simultaneous inhibition of AKT and ER signaling would enhance antitumor efficacy in AKT1m ER+ MBC.

Methods: In an expansion of this study, we administered oral AZD5363 400 mg twice daily, 4 days on 3 days off, and fulvestrant 500 mg, to AKT1m (detected in tumor tissue by local screening and/or plasma BEAMing) ER+ HER2– MBC pts, enrolled into a fulvestrant-naïve (FN) or fulvestrant-resistant (FR) cohort (max 24 pts/cohort). Key objectives included safety and efficacy by RECIST v1.1. We report results of a planned interim analysis conducted when 12 pts/cohort reached maturity for assessment of 24-week clinical benefit rate (CBR), defined as the percentage of responders plus those with stable disease (SD) ≥24 weeks.Data cut-off occurred in June 2017.

Results: At the time of analysis, 24 AKT1m pts (23 E17K, 1 E40K) had received treatment. FN had more visceral disease (83.3% vs 66.7%) and ER+/PR– status (25% vs 8.3%) than FR. Median number of prior anticancer regimens was 4.5 (range 1–9) and 6 (2–11) in FN and FR, respectively, with more chemotherapy (CT) and less hormone therapy (HT) exposure in FN vs FR [3 (0–5) vs 2 (0–6) and 2 (0–4) vs 4 (2–6) prior CT and HT, respectively]. Prior palbociclib was received by 1 (8.3%) and 4 (33.3%) pts in FN and FR, respectively. Clinical efficacy is detailed below; CBR was 33% and 42% in FN and FR, respectively (Table 1). There was 1 unconfirmed partial response in patients treated with prior palbociclib and 3 SD. At data cut-off, 18 pts had discontinued treatment: progressive disease, n=12; adverse events (AEs), n=2; other reasons, n=4. AEs were observed in all 24 pts, most commonly diarrhea (71%), nausea (63%), vomiting and decreased appetite (29%). Grade ≥3 AEs occurred in 13 (54%) pts, most frequently maculopapular rash (n=3), nausea, hyperglycemia and back pain (all n=2). Dose reduction due to AEs occurred in 3 pts.

Table 1. Clinical efficacy FNFREligible for interim data cut-off, n1212ORR, n (%)2 (17)4 (33)CBR, n (%)4 (33)5 (42)Confirmed response (complete/partial response), n (%)2 (17)4 (33)SD ≥24 weeks, n (%)2 (17)1 (8)

Conclusions: AZD5363 plus fulvestrant is clinically active in AKT1m ER+ MBC pts, including in pts with demonstrated prior resistance to fulvestrant. Comparatively lower efficacy was observed in the FN cohort; factors that may have potentially contributed (eg disease characteristics) will be explored. cfDNA and genomic data will also be presented.

Citation Format: Smyth LM, Oliveira M, Ciruelos E, Tamura K, El-Khoueiry A, Mita A, You B, Renouf DJ, Sablin M-P, Lluch A, Mayer IA, Bando H, Yamashita H, Ambrose H, de Bruin E, Carr TH, Corcoran C, Foxley A, Lindemann JPO, Maudsley R, Pass M, Rutkowski A, Schiavon G, Banerji U, Scaltriti M, Taylor BS, Chandarlapaty S, Baselga J, Hyman DM. AZD5363 in combination with fulvestrant in AKT1-mutant ER-positive metastatic breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-21-32.

Abstract P5-21-05: Withdrawn

This abstract was withdrawn by the authors.

Clinical relevance of EMT and stem-like gene expression in circulating tumor cells of metastatic colorectal cancer patients

Using approved methods, circulating tumor cells (CTCs) are only isolated from blood in 30%-50% of metastatic colorectal cancer (mCRC) patients. We previously validated a technique to isolate circulating tumor cells (CTCs) in a cohort of mCRC patients by combining immunomagnetic enrichment of EpCAM⁺/CD45^- cells with qRT-PCR amplification of CK20 and survivin expression. Here, we examined the prognostic utility of CTC epithelial-mesenchymal transition (EMT) and stem cell gene expression. An 8 ml blood sample was collected from 78 consecutive mCRC patients before treatment with investigational and standard chemotherapeutics. The mRNA expression of EMT (PI3Kα, Akt-2, Twist1) and stem cell (ALDH1) markers was measured. Associations between CTC gene expression and progression-free survival (PFS) and overall survival (OS) were determined using Cox regression models. Among patients without CK20 or survivin-expressing CTCs (n=17), 55% had expression of ALDH1, PI3Kα and/or Akt-2. Patients with positive CTC Akt-2 expression had a significantly shorter median PFS (3.0 versus 4.0 months) compared with those without CTC Akt-2 expression in univariable (hazard ratio (HR)=1.61; log-rank P=0.034) and multivariable analyses (HR=1.70; adjusted P=0.041). In univariable analysis, CTC ALDH1 expression was associated with shorter OS (10.0 versus 38.6 months; HR=2.04, P=0.021). Patients with CTCs expressing ALDH1, PI3Kα and/or Akt-2 had a significantly inferior PFS (3.0 versus 7.7 months; HR=1.88, P=0.015) and OS (10.0 versus 26.8+ months; HR=2.25, P=0.050) in univariable, but not multivariable, analysis.

CONCLUSIONS

CTC Akt-2 expression may serve as a clinically useful prognostic marker in mCRC patients and warrants further evaluation in prospective trials.

The Cyclin D1 (CCND1) A870G polymorphism predicts clinical outcome to lapatinib and capecitabine in HER2-positive metastatic breast cancer

BACKGROUND

Lapatinib plus capecitabine emerged as an efficacious therapy in metastatic breast cancer (mBC). We aimed to identify germline single-nucleotide polymorphisms (SNPs) in genes involved in capecitabine catabolism and human epidermal receptor signaling that were associated with clinical outcome to assist in selecting patients likely to benefit from this combination.

PATIENTS AND METHODS

DNA was extracted from 240 of 399 patients enrolled in EGF100151 clinical trial (NCT00078572; clinicaltrials.gov) and SNPs were successfully evaluated in 234 patients. The associations between SNPs and clinical outcome were analyzed using Fisher's exact test, Kaplan-Meier curves, log-rank tests, likelihood ratio test within logistic or Cox regression model, as appropriate.

RESULTS

There were significant interactions between CCND1 A870G and clinical outcome. Patients carrying the A-allele were more likely to benefit from lapatinib plus capecitabine versus capecitabine when compared with patients harboring G/G (P = 0.022, 0.024 and 0.04, respectively). In patients with the A-allele, the response rate (RR) was significantly higher with lapatinib plus capecitabine (35%) compared with capecitabine (11%; P = 0.001) but not between treatments in patients with G/G (RR = 24% and 32%, respectively; P = 0.85). Time to tumor progression (TTP) was longer in patients with the A-allele treated with lapatinib plus capecitabine compared with capecitabine (median TTP = 7.9 and 3.4 months; P < 0.001), but not in patients with G/G (median TTP = 6.1 and 6.6 months; P = 0.92).

CONCLUSION

Our findings suggest that CCND1A870G may be useful in predicting clinical outcome in HER2-positive mBC patients treated with lapatinib plus capecitabine.

Phase I dose-escalation study to determine the safety, pharmacokinetics and pharmacodynamics of brivanib alaninate in combination with full-dose cetuximab in patients with advanced gastrointestinal malignancies who have failed prior therapy

Background:

The objectives of this phase I study were to determine the safety, pharmacokinetics (PK), pharmacodynamics and efficacy of brivanib combined with full-dose cetuximab in patients with advanced gastrointestinal malignancies.

Methods:

Patients with advanced gastrointestinal malignancies who had failed prior therapies received brivanib (320, 600 or 800 mg daily) plus cetuximab (400 mg m^–2 loading dose then 250 mg m^–2 weekly). Assessments included adverse events, PK, tumour response, 2[18F]fluoro-2-deoxyglucose positron-emitting tomography and K-Ras mutation analyses.

Results:

Toxicities observed were manageable; the most common treatment-related toxicities (>10% of patients) were fatigue, diarrhoea, anorexia, increase in aspartate aminotransferase and alanine aminotransferase, acneiform dermatitis, headache, mucosal inflammation, nausea, dry skin, vomiting, hypertension, pruritus, proteinuria and weight loss. Of 62 patients, 6 (9.7%) had objective radiographic partial responses, with an overall response rate of 10%. Median duration of response was 9.2 months; median progression-free survival was 3.9 months.

Conclusions:

The acceptable toxicity profile and efficacy of brivanib observed in this study were promising. These findings are being further evaluated in a phase III study of brivanib plus cetuximab vs cetuximab alone in patients previously treated with combination chemotherapy for K-Ras wild-type advanced metastatic colorectal cancer.

Genetic variations in angiogenesis pathway genes associated with clinical outcome in localized gastric adenocarcinoma

BACKGROUND

Angiogenesis has been attributed to be a well-recognized aspect of human cancer biology. As such, proteinase-activated receptor (PAR)-1, endostatin (ES) and interleukin-8 (IL-8) mediate the regulation of early-onset angiogenesis and in turn impact the process of tumor-growth and disease progression.

PATIENTS AND METHODS

Formalin-fixed paraffin-embedded tissues were obtained from 137 patients with localized gastric cancer at University of Southern California and Memorial Sloan-Kettering Cancer Center medical facilities. DNA was extracted and genotyping was carried out using PCR-restriction fragment length polymorphism-based protocols.

RESULTS

In false discovery rate-adjusted univariate analysis, PAR-1 -506 ins/del (P < 0.001), ES +4349 G>A (P = 0.004), and IL-8 -251 T>A (P < 0.0001) were associated with time to tumor recurrence (TTR). Further, PAR-1 -506 ins/del and IL-8 -251 were associated with overall survival (OS). After adjusting for covariates, IL-8 remained significantly associated with TTR (adjusted P = 0.003) and OS (adjusted P = 0.049), whereas ES was significantly associated with TTR (adjusted P = 0.026).

CONCLUSIONS

Polymorphisms in PAR-1, ES, and IL-8 may serve as independent molecular prognostic markers in patients with localized gastric adenocarcinoma. The assessment of the patients' individual risk on the basis of interindividual genotypes may therefore help to identify patient subgroups at high risk for poor clinical outcome.

Association of gender, age, and ethnicity with survival in patients with pancreas cancer

e15587

Background: Pancreatic cancer (PC) is the fourth leading cause of cancer death in the United States. However little is still known about factors that influence its development and progression. Recent data suggest that PC is, at least in part, an estrogen- dependent disease; there is growing epidemiological evidence that aspects of reproductive history and hormonal exposure are associated with risk of this disease. It was shown that age at menarche of <13 is associated with less risk of PC. However no data are available whether gender is associated with outcome in patients with PC. The purpose of this study was to test whether age, gender or ethnicity influence the outcome in PC. Methods: The data of the 50,302 adults diagnosed with PC between 1988 and 2004 were extracted from the Surveillance Epidemiology and End Results public use database. These included 24,240 patients diagnosed with localized pancreatic cancer (LPC) and 26,062 patients with metastatic pancreatic cancer (MPC). Demographic, clinical variables and survival time were retrieved. The primary endpoint was overall survival. We constructed Cox proportional hazards models to evaluate association between patient characteristics and survival in LPC and MPC separately. Pair interactions were also tested. Results: On multivariate analysis gender, age, race, marital status, tumor size, grade, histology, type of treatment and lymph node involvement were found to be independent predictors of survival. Females had a significant longer survival, with an HR of 0.959 (95% CI: 0.932–0.987) among patients with LPC and an HR of 0.918 (95%CI: 0.894–0.942) among patients with MPC. Each age group displayed a significant longer survival than its correspondent older age group. When we combined age and gender in the analysis, females had a longer survival than males in each single age group in the MPC group. In the LPC group the longer survival of female patients was only observed in the youngest age group. Conclusions: This is the first and largest study to address gender and outcome in PC. Our data suggest that the estrogen pathway may play an important prognostic role in patient with this disease. These data also warrant further in vitro and in vivo investigations on the mechanisms of estrogen and pancreas progression.

No significant financial relationships to disclose.

Colorectal cancer susceptibility variants and clinical outcome in adjuvant and metastatic colorectal cancer

4051

Background: Recent genome-wide association studies had identified colorectal cancer susceptibility loci on chromosomes 8q24 (rs6983267), 15q13(rs4779584), 18q21(rs4939827, rs12953717 and rs4464148), 10p14(rs10795668) and 8q23.3(rs16892766). Although the function role of these germline variants are unclear, given the importance of these variants and colorectal cancer risk, we have carried out the first pilot study to explore the association of these variants and clinical outcome. We used pooled data from two CRC-cohorts (locally advanced and metastatic CRC), and investigated the hypothesis that these germline variants may be associated with clinical outcome in adjuvant and metastatic colorectal cancer patients. Methods: Whole blood was collected from 515 patients with locally advanced (n=197) and metastatic CRC (n=318). After extraction of genomic-DNA, germline variants were genotyped as previously described (Haiman et al, Nat Genet, 2007). The genotype success rate was 98%. Blinded repeat samples (5%) were included for quality control purposes; genotype concordance was ≥ 99%. Results: Our results suggest that rs10795668 at 10p14 and rs719725 are significantly associated with time to tumor recurrence in adjuvant colorectal cancer patients, patients with rs10795668 AA genotype had significantly increased risk of time to tumor recurrence compared with those harboring G allele (TG+GG) patients(p=0.05, log-rank test). In metastatic cancer patients, we found rs4939827 at 18q21.1 were significantly associated with overall survival in female patients and rs10795668 at 10p14 were significantly associated with OS in male patients, respectively (p<0.05). Conclusions: Our preliminary results suggest cancer risk alleles may also associated with clinical outcome in adjuvant and metastatic colorectal cancer. Moreover, this correlation is sex-specific in metastatic colorectal cancer. Further comprehensive trials warranted to confirm our pilot findings.

[Table: see text]

Pharmacogenetic analysis in metastatic colorectal cancer (mCRC) patients (pts) treated with second-line irinotecan (IR)+/− cetuximab (CB): The EPIC experience

4022

Background: EPIC, a multinational phase III clinical trial with IR + CB vs IR alone in mCRC pts in the second-line setting after failure of FOLFOX demonstrated a benefit for IR+CB in progression-free survival (PFS) and response rate (RR). We evaluated functional germline polymorphisms involved in the EGFR- (EGF, EGFR), angiogenesis- (VEGF, IL-8, CXCR-2) - and drug- metabolism related genes (UGT1A1, MTHFR) for their potential role as molecular predictors for clinical outcome in pts treated with CB/IR vs. IR alone. Methods: DNA was extracted from all available formalin-fixed paraffin-embedded tumor samples from the phase III EPIC trial (US sites only). Genotyping was performed using PCR-RFLP assays and 5’ -end [g-33P] ATP’ labeled PCR-protocols. Results: 186 pts were treated either with IR/CB (arm A, 84 pts) or IR (arm B, 102 pts) only. In arm A, 11/84 pts (13%) showed CR or PR, whereas 73/84 (87%) pts had SD or PD. For arm B, 6/102 pts (6%) showed CR or PR, whereas 96/102 pts (94%) had SD or PD. Median PFS in arm A was 3.0 months (95%CI: 2.4- 4.1 months) vs 2.7 months (95%CI: 2.2–2.9 months) in arm B; median overall survival (OS) was 9.3 months (95%CI: 7.1–12.1 months) in arm A vs. 12.3 months (95%CI: 10.4- 17.9 months) in arm B. K-ras mutation status was not significantly associated with PFS or response to CB/IR in the subgroup of 186 patients. We found an EGFR-CA- repeat in intron 1 in arm A to be associated with PFS (p=0.031, log-rank test). In arm B, we found a significant association with RR (p=0.0103, Fisher's exact test) for MTHFR1298. Furthermore, MTHFR 677 (p =0.0048, log-rank test) and MTHFR 1298 (p=0.038, log-rank test) were also found to be associated with OS in arm B. In multivariate analysis, EGFR-CA-repeat was significantly associated with PFS (adjusted p= 0.023). Furthermore, MTHFR 677 and MTHFR 1298 was associated with OS (adjusted p=0.028 and 0.026, respectively, Cox-proportional hazards models), independent from K-ras mutation status, race and number of disease sites. Conclusions: Our study demonstrates the potential predictive value of polymorphisms in the EGFR- and MTHFR- gene in mCRC pts treated with IR+ CB. Further validation in additional clinical trials is necessary.

[Table: see text]

Gender disparities in hepatocellular cancer survival

e15517

Background: Recent reports suggest that estrogen mediated inhibition of IL-6 protects against the development of HCC and may explain the decreased risk of liver cancer in women. We investigated the relation-hip between gender, age, and survival for patients with localized HCC. Methods: We identified 11,097 patients with localized, histologically defined HCC, from 1988- 2003, using the Surveillance, Epidemiology, and End Results (SEER) registry. Age at diagnosis, sex, ethnicity, and overall survival were evaluated using Cox proportional hazards model. The models were adjusted for treatment modality, tumor differentiation, tumor size, lymph node involvement, and number of lesions; they were stratified by year of diagnosis and SEER registry site. Results: 8,111 (73%) patients were men and 2,986 (27%) were women. In univariate and multivariate analyses, female gender, young age (< 55 yo), and Asian ethnicity were all associated with improved overall survival (p<0.001). In patients less than 55 yo, women had a superior OS and cancer specific survival (CSS) when compared to men (OS: 18 months vs. 9, CSS: 31 months vs. 14, p<0.001). Conversely, in patients older than 55, there were no gender differences (OS: 8 months vs. 8, CSS 13 months vs. 11, p = 0.08). Local therapies, including, ablation (HR = 0.47 [0.43–0.53]), hepatectomy (HR = 0.40 [0.36–0.44]), radiation (HR = 0.67 [0.57–0.78]) and transplantation (HR = 0.17 [0.15–0.20]) were also associated with improved survival. There were no interactions identified between gender and treatment use. Conclusions: To our knowledge, this is the first report to highlight the superior outcome of premenopausal women with HCC compared to men. We postulate a potential role for estrogen in influencing the biology of HCC and the response to treatment. These observations are consistent with ones made in other gastrointestinal cancers and with reported preclinical data suggesting a protective role for estrogen. Further studies that confirm these observations and elucidate the biology of estrogen's influence on HCC are needed.

[Table: see text]

No significant financial relationships to disclose.

Effect of gender and age on overall survival in patients with esophageal cancer

4541

Background: The American Cancer Society estimated that during 2008 approximately 16,470 new esophageal cancer cases would be diagnosed in the United States. Previous studies indicate that the incidence of esophageal cancer is more in males than females; however the influence of sex in the progression of esophageal cancer is not clearly understood. In vitro and in vivo models showed that administration of estradiol significantly inhibited the growth of ER-positive and AR-positive KSE-1 tumors in both males and females in conjunction with an increase in the estradiol levels and a decrease in the DHT levels in the serum. Thus we tested the clinical significance of sex in the overall survival of esophageal cancer using SEER data. Methods: A total of 21,584 patients with localized and metastatic esophageal cancer from 1988–2004 were screened using the SEER registry. The patients were divided into age at diagnosis, sex and ethnicity. The analysis for overall survival was based on the Cox proportional hazards model adjusted for marital status, site of primary tumor, treatment, histology and tumor grade and stratified by year of diagnosis and SEER registry site. Pairwise interactions (age and sex, age and race, and sex and race) were also examined. Results: Females with localized esophageal cancer had significantly longer overall survival compared to males (p<0.001). In metastatic esophageal cancer, females seemed to have longer overall survival than males (p=0.054). Overall survival decreased with increasing age (p<0.001). African Americans with localized esophageal cancer have worse median overall survival compared to Caucasians (p<0.001). No significant difference was noted with respect to ethnicity in metastatic esophageal cancer (p=0.22). Also pairwise interactions did not have significant difference. Conclusions: This is the first and largest study showing gender as an independent prognostic factor in patients with localized and metastatic esophageal cancer. Females had a significant better overall survival than males in esophageal cancer suggesting that sex hormone pathways may have a potential impact on tumor progression. These data warrant further studies to explore the role of these pathways in the diagnosis and treatment of esophageal cancer.

No significant financial relationships to disclose.

Association of a germ-line variant in the K-ras 3’ untranslated region with response and progression-free survival in patients with mCRC treated with single-agent cetuximab (IMCL-0144) or in combination with cetuximab (EPIC) independent of K-ras mutation status

4061

Background: Recent studies have found K-ras mutation status predicts response to EGFR inhibitors in mCRC. An in vitro study demonstrated let-7 microRNA family can regulate RAS expression by binding to the 3’UTR of RAS gene. Chin et al found a SNP in a let-7 microRNA complementary site (LCS) in the K-ras 3’ UTR increases cancer risk in NSCLC. We tested the hypothesis whether this SNP may be associated with clinical outcome in 130 mCRC patients enrolled in IMCL-0144 trial and in 186 pts enrolled in EPIC trial independent of K-Ras mutation status in the tumor. Methods: K-ras lcs 6 SNP was tested in 130 mCRC patients enrolled in IMC-0144 phase II clinical trial (single agent cetuximab) and in 186 mCRC patients enrolled in a second line phase III trial of cetuximab plus irinotecan versus irinotecan alone (EPIC). Genomic DNA was extracted from dissected formalin fixed paraffin embedded tumor tissue and K-ras mutation status and the polymorphism were analyzed using direct sequencing and PCR-RFLP technique. Results: The G harboring allele frequency in K-ras lcs6 was 8% in IMC-0144 and 11% in EPIC. K-ras lcs6 polymorphism was significantly associated with tumor response in patients with wild type K-ras in IMC-0144. The 12 pts harboring a G allele (TG+GG) had a 42% partial response (PR) rate compared to 55 pts with TT genotype with only 9% PR.(p=0.02, Fisher's-exact test). However, pts with TT genotype enrolled in EPIC treated with CPT-11 and cetuximab with mutant K-ras had a significantly better PFS of 12 weeks (95% CI 6.4–18) compared to those harboring the a G allele with median PFS of 6.4 weeks (95% 5.7–7) (p=0.037. log-rank test). There was no association between this polymorphism and clinical outcome in patients with wild type K-ras enrolled in EPIC. In a multivariate analysis the polymorphism remained independently associated with PFS in EPIC. Conclusions: Our data suggest for the first time that the functional germline polymorphism in K-ras lcs6 may be a potential predictive marker in mCRC patients treated with cetuximab-based chemotherapy independent of K-ras mutation status. This finding warranted further confirmative clinical trials.

[Table: see text]

Use of genetic variants to predict clinical outcome in patients (pts) with metastatic colorectal cancer (mCRC) treated with first-line 5-FU or capecitabine in combination with oxaliplatin and bevacizumab (FOLFOX/BV or XELOX/BV)

4070

Background: Recent studies suggested polymorphisms involved in angiogenesis related genes associated with clinical outcome in pts treated with the VEGF-inhibitor bevacizumab. (Schneider et al. JCO 2008, Manegold et al ASCO 2008). We evaluated functional polymorphisms involved in angiogenesis- (VEGF, KDR, IL-6, CXCR1 and-2), apoptosis (p53) and cell-proliferation (MMP2,-7 and-9, ICAM)-related pathways in an expanded patient cohort for their potential prognostic or predictive role in clinical outcome. Methods: Genomic DNA was extracted from 79 mCRC pts (treated with first-line FOLFOX/BV or XELOX/BV at USC) from peripheral blood. Genotyping was performed using PCR-RFLP assays or direct sequencing. Results: 79 pts (47 men, 32 women) with a median age of 56 years (range 29–81), were treated with either FOLFOX/BV (33 pts) or XELOX/BV (46 pts). Radiologic response: 2/79 pts (3%) CR, 41/79 pts (52%) PR, 32/79 pts (41%) SD and 3/79 pts (4%) DP. At a median follow-up of 32.0 months (range: 1.4- 47.8 months), the median time to progression was 10.8 months (95% CI: 8.1–14.9). We found IL-6 G- 174C (p=0.025, Fisher's exact test) and p53 codon 72 (p=0.029, Fisher's exact test) polymorphisms associated with response to BV-therapy. Furthermore, there were statistically significant associations between genomic polymorphisms in MMP-9, CXCR-1 and PFS (p=0.023 and p=0.014, respectively, log-rank test). Pts with 2 G- alleles in CXCR-1 G+2607C (median PFS=13.7 months, 95% CI:8.4–16.4) and pts homozygous for the C-allele in MMP-9 C-1562T (median PFS= 13.9 months, 95% CI: 10.1–15.8) had longer PFS compared to pts with any C-allele in CXCR-1 G+2607C (median PFS = 7.9 months, 95% CI: 6.9–10.2) and pts with any T-allele in MMP-9 C-1562T (median PFS 7.2 months, 95% CI: 5.3–11.0), respectively. Conclusions: These are the first data to predict clinical outcome in mCRC pts treated with FOLFOX/BV or XELOX/BV. Our data demonstrate that functional polymorphisms in angiogenesis related genes predict response and PFS in pts treated with the angiogenesis- inhibitor BV. However, confirmation of these findings in larger, prospective genotype-guided clinical trials is warranted.

[Table: see text]

A phase I study of BMS-582664 (brivanib alaninate), an oral dual inhibitor of VEGFR and FGFR tyrosine kinases, in combination with full-dose cetuximab in patients (pts) with advanced gastrointestinal malignancies (AGM) who failed prior therapy

14018

Background: Brivanib is an oral prodrug of BMS-540215, a dual tyrosine kinase inhibitor of VEGFR and FGFR signaling. Prior studies have validated both VEGF and EGF signaling pathways as targets in AGM. The MTD of single-agent brivanib is 800 mg qd (ASCO #3051, 2006). Methods: An open-label Phase I dose-escalation study of brivanib in combination with cetuximab was conducted in pts with AGM who failed prior therapy. Brivanib was given po Day 1 and qd from Day 8, starting at 320 mg. Cetuximab was given IV Day 8 (400 mg/m2) then weekly (250 mg/m2). Dose escalation of brivanib continued to 800 mg qd, when an expansion cohort for pts with colorectal cancer (CRC) was opened for additional safety and efficacy. Fresh tissue and blood sampling for biomarker and pharmacokinetic (PK) analysis was performed. FDG-PET was obtained at Baseline X 2, Days 15 and 56. Tumor response (modified WHO) was evaluated q 8 weeks. Results: 18 pts (15 CRC, 2 esophageal, 1 other) were treated with 320, 600 or 800 mg qd of brivanib in combination with cetuximab for a median of 8 weeks (range 1 - 20+). A single DLT, bilateral pulmonary emboli, occurred at 320 mg qd. Few treatment-related AEs occurred across the 3 cohorts (Table). PK/biomarker data is pending. Available FDG-PET results from measurements in 8 pts with 2–3 target lesions showed good baseline reproducibility in SUVpeak, SUVmean and SUVmax, with intra-subject CV of 3.6%, 7.2% and 9.3%, respectively. Conclusions: Brivanib in combination with full-dose cetuximab was well tolerated at ≤800 mg qd and did not result in enhancement of cetuximab associated AEs. Pre-treatment FDG-PET is a highly reproducible imaging modality.

[Table: see text]

[Table: see text]

Tumor VEGFA gene expression is associated with serum lactate dehydrogenase (LDH) levels and intratumoral mRNA expression of genes involved in glycolysis in patients with metastatic colorectal cancer (mCRC)

3530

Background: It is well known that angiogenesis and glycolysis are regulated by hypoxic conditions. Recent clinical trials (CONFIRM1 and CONFIRM2) have shown that patients with mCRC with high serum LDH benefited from PTK787/ZK 222584, a VEGF receptor tyrosine kinase inhibitor. We tested the hypothesis that patients with high serum LDH have increased intratumoral expression of genes involved with hypoxia (hypoxia inducible factor (HIF1a and 2a) and lactate dehydrogenase A (LDHA) and glycolysis (glucose transporter 1 (Glut-1) and genes involved in angiogenesis such as vascular endothelial growth factor A (VEGFA) and neuropilin 1 (NRP1) in patients with mCRC. Methods: 78 formalin fixed paraffin embedded (FFPE) tumor samples from 36 patients (20 males, 16 females: Median age 59 years (range 29–84) with mCRC who underwent first line therapy (not from CONFIRM trials) were analyzed. In addition, tumor gene expression was correlated with serum LDH levels from the same group of patients. FFPE tissues were dissected using laser-captured microdissection and analyzed LDHA, VEGFA, HIF1a, HIF2a, Glut-1 and NRP1 mRNA expression using a quantitative real-time RT-PCR method. Gene expression values (relative mRNA levels) are expressed as ratios between the target gene and internal reference gene (beta-actin). Results: Spearman Rank Correlation Analysis of Associations Between serum LDH levels and Gene Expression values. Conclusions: Our results demonstrate that intratumoral gene expression of LDHA, HIF1a and HIF2a, Glut-1 and VEGFA are significantly correlated. Patients with high serum LDH have increased intratumoral gene expression of VEGFA. These results support the hypothesis that serum LDH levels may serve as a surrogate marker for activation of the HIF related genes in the tumor. These observations may explain the efficacy of PTK787 in metastatic colorectal cancer patients with high serum LDH levels.

[Table: see text]

[Table: see text]

Intratumoral mRNA levels predict clinical outcome in patients with metastatic colorectal cancer treated in a prospective clinical trial with 5-FU and oxaliplatin

10010

Background: 5-flurouracil (5-FU) and Oxaliplatin-based therapy is one of the most frequently used combinations in the treatment of advanced colorectal cancer (CRC). There are no validated and established predictive factors for clinical outcome following 5-FU/Oxaliplatin treatment. We had shown an association between intratumoral mRNA levels of TS and ERCC1 involved in 5-FU metabolism and DNA repair, respectively, and survival to 5-FU/Oxaliplatin chemotherapy in advanced CRC in a retrospective study. Now we investigated whether intratumoral mRNA levels of these two genes and others involved in 5-FU metabolism (DPD, TP, dUTPase), DNA repair (ERCC2, XRCC1), angiogenesis (COX-2, EGFR, IL-8, PLA2), and drug detoxification (GSTP-1) predict the clinical outcome of patients with CRC in a prospectively designed biomarker study. Methods: 85 patients with metastatic CRC treated with second-line 5-FU/Oxaliplatin from the prospective trial were included. mRNA levels of 12 genes were assessed from paraffin- embedded tissue samples using laser capture microdissection and quantitative Real-time PCR. Overall survival (OS) was the primary endpoint. Progression-free survival (PFS), response, and toxicity were the secondary endpoints. Results: There were 40 women and 45 men (median age 60 years; range 29–87), median survival of 9.7 ms, median PFS of 4.2 ms, CR in 1 (1%) patient, PR in 15 (18%), SD in 36 (43%) and PD in 32 (38%) patients. High intratumoral mRNA levels of PLA2, TP, GSPTP-1 and low mRNA levels of COX-2 were each significantly associated with shorter OS (P≤0.05, log-rank test). There was a trend in the association between high mRNA levels of PLA2 and shorter PFS (P=0.08). In addition, high mRNA levels of XRCC1 and IL-8 were each significantly associated with high risk of cumulative grade 3+ toxicity (P≤0.05). No significant association was found between mRNA levels and response to 5-FU/Oxaliplatin. Conclusions: This study suggests that mRNA levels of PLA2, TP, GSTP-1, COX-2, XRCC1, and IL-8 may be useful to predict the outcome of patients with metastatic CRC with second-line 5-FU/Oxaliplatin chemotherapy. These findings should be validated with future basic sciences studies and prospective clinical trials.

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Polymorphism in sodium-channel alpha 1-subunit (SCN1A) predicts response, TTP, survival, and toxicity in patients with metastatic colorectal cancer treated with 5-FU/oxaliplatin

3533

Background: Genetic polymorphisms in DNA repair and drug metabolism pathways have been shown to be associated with efficacy and toxicity in patients with metastatic colon cancer treated with 5-FU/oxaliplatin. Recent studies demonstrated in in vitro models that the neurotoxicity associated with oxaliplatin may be linked to an effect on neuronal voltage-gated sodium channels (VGSC). In vitro and in vivo models showed that increased VGSC alpha gene expression was associated with metastatic potential, proliferation and progression of breast and prostate cancer indicating a role in predicting toxicity and efficacy to chemotherapy. We tested the hypothesis whether VGSC gene polymorphisms may predict clinical outcome in a phase II study of combination oxaliplatin with 5-FU in patients with colorectal cancer refractory to 5-FU and/or irinotecan based chemotherapy. Methods: 173 patients were enrolled in this phase II study. 152 patients (male/female; 78/74, median age; 60), median follow up of 18.6 months, response rate of 19%, median time to tumor progression 4.2 months and median survival of 10.3 months. Grade 3/4 toxicity was seen in 60% with GI toxicity of 42% and Neurotoxicity of 11%. The dose of oxaliplatin was 130mg/m2 every 3 weeks and 5-FU was 200mg/m2/day CI for 10 weeks followed by 2 weeks rest. We tested the 12 VGSC genes polymorphisms (SCN1A, 1B, 1A1, 1A2, 1A3, 1A4, 1A5, 1A A3169G SNP, 1A C1702T Nonsense Mutation, 1A T1067A SNP, 1A C3637T SNP, SCN8A Ref SNP 303802). Genomic DNA was extracted from peripheral blood samples and polymorphisms were analyzed by PCR-based RFLP technique. Results: Patients with SCN1A T1067A SNP T/T genotype showed a significant better response rate (p=0.02, 21.9% [23/105] vs. 11.3% [5/44]), TTP (p=0.02, 4.6 months vs. 3.4 months), overall survival (p<.001, 12.3 months. vs. 8.0 months.), and frequency of grade 3/4 toxicity (p=.002) compare to patients with T/A genotype. No A/A genotype was observed. Conclusions: SCN1A gene polymorphism may be potential molecular marker for survival and toxicity in patients with colorectal cancer treated with 5-FU/oxaliplatin. In vitro studies are ongoing to identify the mechanism of resistance by SCN1A.

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