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ObjectivesAnetumab ravtansine is an antibody-drug conjugate consisting of a fully human anti-mesothelin monoclonal antibody conjugated to cytotoxic maytansinoid tubulin inhibitor DM4. Mesothelin is highly expressed in ovarian cancer. This phase Ib study determines the safety, pharmacokinetics, and anti-tumor activity of anetumab ravtansine and pegylated liposomal doxorubicin in mesothelin-expressing platinum-resistant ovarian cancer.MethodsAnetumab ravtansine (5.5 or 6.5 mg/kg) and pegylated liposomal doxorubicin (30 mg/m2) were administered intravenously every 3 weeks to 65 patients with platinum-resistant epithelial ovarian cancer. Mesothelin expression was assessed by central immunohistochemistry. Adverse events, tumor response (RECIST 1.1), and progression-free survival were determined. Biomarker samples were assessed by ELISA and next-generation sequencing.ResultsIn dose escalation, nine patients received anetumab ravtansine across two doses (5.5 or 6.5 mg/kg). The maximum tolerated dose of anetumab ravtansine was 6.5 mg/kg every 3 weeks and no dose-limiting toxicities were observed. In dose expansion, 56 patients were treated at the maximum tolerated dose. The most common treatment-emergent adverse events of any grade were nausea (47.7%), decreased appetite (43.1%), fatigue (38.5%), diarrhea (32.3%), and corneal disorder (29.2%). In all treated patients the objective response rate was 27.7% (95% CI 17.3% to 40.2%), including one complete (1.5%) and 17 partial responses (26.2%), with median duration of response of 7.6 (95% CI 3.3 to 10.2) months and median progression-free survival of 5.0 (95% CI 3.2 to 6.0) months. In an exploratory analysis of a sub-set of patients (n=19) with high mesothelin expression who received ≤3 prior lines of systemic therapy, the objective response rate was 42.1% (95% CI 20.3% to 66.5%) with a median duration of response of 8.3 (95% CI 4.1 to 12.0) months and median progression-free survival of 8.5 (95% CI 4.0 to 11.4) months.ConclusionsAnetumab ravtansine and pegylated liposomal doxorubicin showed tolerability and promising clinical activity. These results established the dose schedule and the mesothelin-positive target population of this combination for a phase III study in platinum-resistant ovarian cancer.Trial registration numberNCT02751918.

This chapter contains a methodological framework for choosing a model for the meta-analysis of very few studies and selecting an estimation method for the chosen model by means of study characteristics and by comparing results yielded by different approaches. When the results are inconclusive between different estimation methods, it might be the best solution to refrain from a quantitative meta-analysis but to summarize the study results by means of a qualitative evidence synthesis.

This chapter contains a methodological framework for choosing a model for the meta-analysis of very few studies and selecting an estimation method for the chosen model by means of study characteristics and by comparing results yielded by different approaches. When the results are inconclusive between different estimation methods, it might be the best solution to refrain from a quantitative meta-analysis but to summarize the study results by means of a qualitative evidence synthesis.

Introduction: The combination of the PI3K inhibitor copanlisib (C) plus the anti-CD20 antibody rituximab (R) has been shown to be superior to R plus placebo (P) in patients with relapsed iNHL (Matasar et al. Lancet Oncol 2021). We report here the biomarker analysis to assess correlation with response of baseline samples for PTEN expression and GEP signatures. Methods: Adult patients with relapsed B-cell iNHL were randomly assigned 2:1 to either C + R or P + R; standard dosing on a 28-day cycle applied. Either fresh or archival tumor tissues were collected for central pathology review and biomarker analysis. Extraction of the formalin-fixed, paraffin-embedded (FFPE) tissue slides was performed using the Qiagen AllPrep DNA/RNA FFPE Kit, where quality was assessed using a combination of Agilent TapeStation for integrity and ThermoFisher NanoDrop for quantity and purity. Immunohistochemistry (IHC) for PTEN expression was performed by Mosaic Laboratories (Lake Forest, CA, USA) and RNA sequencing analysis was performed by Almac Diagnostics (Durham, NC, USA). GEP was also conducted using claraT pathway signatures provided by Almac. Results: Patients with complete, very good partial, and partial objective responses were combined in a “responders” group and compared against all other patients (“non-responders” group). Data from PTEN IHC were available for 222 patients (149 for C + R; 73 for P + R). There was no statistically significant difference in response with PTEN presence or absence for the 3 subgroups - total iNHL, follicular lymphoma (FL), and non-FL. Also, baseline PTEN expression did not show significant correlation with best overall response. C + R treatment improved median progression-free survival (PFS) for all patients, with a statistically significant benefit to those with PTEN presence in all 3 subgroups. For patients treated with P + R, Kaplan-Meier plots and log-rank tests showed statistically improved median PFS in patients with PTEN absence vs PTEN presence in overall iNHL (p=0.031) and FL (p=0.0021). Data from GEP were available for 202 patients (133 for C + R; 69 for P + R). The association with best overall response and PFS was analyzed using specific biomarker gene sets and/or 23 preselected clinical parameters. Association of GEP analysis based on hypothesis-based modeling, single-gene hypothesis-free modeling, and claraT pathway signatures showed no predicted responsiveness or PFS that was statistically significant. Conclusions: C + R improved median PFS in the overall iNHL, FL, and non-FL groups, with a statistically significant improvement in the PTEN-positive population. In the P + R group, PTEN-positive patients had worse PFS in all 3 subgroups. Data from GEP and pathway analysis did not show correlation with overall response or PFS. Citation Format: Shalini Chaturvedi, Anke Schulz, Lidia Mongay Soler, Barrett H. Childs, Matthew Matasar, Pier Luigi Zinzani. Biomarker assessment of PTEN protein expression and gene expression profiling (GEP) in a phase III study of copanlisib in combination with rituximab in patients with indolent non-Hodgkin lymphoma (iNHL) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB523.

89 Background: Combination treatment with regorafenib (80–120 mg/day, PO, 3 wks on/1 wk off) plus nivolumab (480 mg IV Q4W) showed manageable safety but modest efficacy in a phase 2 study of 70 pts from North America with pMMR/MSS chemotherapy-resistant metastatic CRC (mCRC). Five pts had a partial response (PR; objective response rate [ORR]: 7%); all did not have liver metastases at baseline (n = 5/23; ORR: 22%). One pt had a confirmed complete response (CR) after the primary completion analysis of the study (ASCO 2021). This retrospective exploratory analysis investigated the potential association between specific biomarkers and anti-tumor activity, and how those biomarkers are modulated by treatment with regorafenib plus nivolumab. Methods: In formalin-fixed paraffin-embedded tumor samples obtained at baseline and Cycle (C) 2 Day (D) 8, immune-related biomarkers were assessed via immunohistochemistry (IHC), and RNA sequencing was used for gene expression profiling/gene signatures. Pre-/on-treatment blood samples were collected to measure circulating tumor DNA (ctDNA) and soluble biomarkers. Results: A total of 40 and 27 baseline tumor samples and 14 and 5 paired tumor samples at baseline/C2D8 were available for IHC and RNA sequencing, respectively. Higher baseline protein and mRNA expression of biomarkers for pre-existing immune sensitivity (eg, effector T cells) trended with anti-tumor activity. These biomarkers were expressed at lower levels in pts with liver metastases vs those without liver metastases at baseline. Cytotoxic T cell density was elevated on C2D8 but did not correlate with anti-tumor activity. Increased mean variant allelic frequency in ctDNA at C2D1 predominated in pts with progressive disease (PD), while clearance of ctDNA at C2D1 was only noted for the one pt with a CR. High clonal tumor mutational burden in ctDNA showed a numerical trend with anti-tumor activity (PD vs. SD/PR; P=0.058) and PFS (P = 0.072). Baseline serum levels of select markers related to angiogenesis (eg, vascular endothelial growth factor [VEGF] D) were associated with inferior anti-tumor activity (P = 0.002). Serum levels of immune-related soluble biomarkers (eg, tumor necrosis factor alpha) increased on treatment (P < 0.005), while levels of soluble VEGF receptor 2 decreased (P < 0.001). Conclusions: This study of pts with MSS mCRC treated with regorafenib plus nivolumab suggests that baseline tumor biomarkers for pre-existing immune sensitivity trended with anti-tumor activity, whereas select baseline peripheral biomarkers related to angiogenesis trended with inferior anti-tumor activity. Pharmacodynamics effects were observed, yet no significant correlation with anti-tumor activity was found. Due to the small sample size and retrospective nature, these analyses are hypothesis-generating. Clinical trial information: NCT04126733.

Introduction This X-VeRT (eXplore the efficacy and safety of once-daily oral riVaroxaban for the prevention of caRdiovascular events in patients with nonvalvular aTrial fibrillation scheduled for cardioversion) substudy evaluated the effects of treatment with rivaroxaban or a vitamin-K antagonist (VKA) on levels of biomarkers of coagulation (D-dimer, thrombin–antithrombin III complex [TAT] and prothrombin fragment [F1.2]) and inflammation (high sensitivity C-reactive protein [hs-CRP] and high-sensitivity interleukin-6 [hs-IL-6]) in patients with atrial fibrillation (AF) who were scheduled for cardioversion and had not received adequate anticoagulation at baseline (defined as, in the 21 days before randomization: no oral anticoagulant; international normalized ratio Methods Samples for biomarker analysis were taken at baseline (n = 958) and treatment completion (42 days after cardioversion; n = 918). The influence of clinical characteristics on baseline biomarker levels and the effect of treatment on changes in biomarker levels were evaluated using linear and logistic models. Results Baseline levels of some biomarkers were significantly associated with type of AF (D-dimer and hs-IL-6) and with history of congestive heart failure (hs-CRP, D-dimer, and hs-IL-6). Rivaroxaban and VKA treatments were associated with reductions from baseline in levels of D-dimer (−32.3 and −37.6%, respectively), TAT (−28.0 and −23.1%, respectively), hs-CRP (−12.5 and −17.9%, respectively), and hs-IL-6 (−9.2 and −9.8%, respectively). F1.2 levels were reduced from baseline in patients receiving a VKA (−53.0%) but not in those receiving rivaroxaban (2.7%). Conclusion Anticoagulation with rivaroxaban reduced levels of key inflammation and coagulation biomarkers to a similar extent as VKAs, with the exception of F1.2. Further investigation to confirm the value of these biomarkers in patients with AF is merited.

BACKGROUND: Non-vitamin K antagonist oral anticoagulants including rivaroxaban are widely used for stroke prevention in patients with atrial fibrillation (AF). We investigated the relationship between plasma biomarkers (indicative of thrombogenesis, fibrinolysis and inflammation) and left atrial thrombus resolution after rivaroxaban treatment.METHODS: This was an ancillary analysis of the X-TRA study, which was a prospective interventional study evaluating the use of rivaroxaban for left atrial/left atrial appendage (LA/LAA) thrombus resolution in AF patients. We assessed various biomarkers of thrombogenesis/fibrinolysis [D-dimer, plasminogen activator inhibitor-1 (PAI-1), prothrombin fragment 1 + 2 (F1,2), thrombin-antithrombin (TAT) complexes, von Willebrand factor (vWF)] and inflammation [high-sensitivity interleukin-6 (hsIL-6), and high-sensitivity C-reactive protein (hsCRP)], measured at baseline and after 6 weeks' of rivaroxaban treatment.RESULTS: There were significant decreases in the mean levels of hsCRP, D-dimer, vWF, and TAT from baseline to end of treatment with rivaroxaban. Although none of the thrombogenesis/fibrinolysis biomarkers showed a significant relationship with thrombus resolution, high inflammatory biomarkers at baseline were significantly associated with an increased chance of the thrombus being completely resolved (hsIL-6) or reduced/resolved (hsCRP).CONCLUSIONS: Biomarkers of inflammation are significantly associated with LA/LAA thrombus outcomes in AF patients prospectively treated with rivaroxaban.

Firms are increasingly evaluating whether or not to introduce new business models based on digital technologies, also in knowledge-intensive, risky contexts long immune to them. In the financial in...

IntroductionCurrently, the Institute for Quality and Efficiency in Health Care (IQWiG) does not restrict literature searches by language. Given limited resources, it is unclear whether the effort put into screening and translating studies published in non-English and non-German (nEnG) languages yields much new information when compared to including only English and German literature. Therefore, we aimed to analyze the impact of nEnG literature on the conclusion of IQWiG's health technology assessments (HTAs).MethodsWe checked for seventy-two IQWiG HTAs (all non-drug intervention HTAs published until August 2018 and three additional HTAs on drugs) whether they included nEnG studies. For all HTAs including at least one nEnG study, we analyzed whether the statistical significance would have changed for any endpoint without the respective nEnG study(ies). If no endpoint was impacted by a nEnG study, we classified the study as non-relevant to the HTA's conclusion and specified a reason for this.ResultsOf seventy-two HTAs, twenty-nine (40 percent) included a total of eighty-three nEnG publications). Three HTAs were impacted by the inclusion of altogether seven Chinese publications. For one HTA on systemic therapy, five endpoints’ conclusions were changed; for the other two HTAs, the statistical significance would have changed for one endpoint each. The remaining seventy-six publications (included in sixty-nine HTAs) were judged as non-relevant to the HTA's conclusion, the most prominent reason being “meta-analysis would have had the same result without respective study” (44 percent of nEnG publications).ConclusionsOnly three of seventy-two HTAs (4 percent) were impacted by nEnG publications, the changes being minimal for two of these. When faced with limited time or personnel resources, searching only for English and German publications may be sufficient, especially when generalizability issues are a possible concern.

Background: Activating KRAS mutations are reported in up to 90% of pancreatic cancers. Refametinib potently inhibits MEK1/2, part of the MAPK signaling pathway. This phase I/II study evaluated the safety and efficacy of refametinib plus gemcitabine in patients with advanced pancreatic cancer. Methods: Phase I comprised dose escalation, followed by phase II expansion. Refametinib and gemcitabine plasma levels were analyzed for pharmacokinetics. KRAS mutational status was determined from circulating tumor DNA. Results: Ninety patients overall received treatment. The maximum tolerated dose was refametinib 50mg twice daily plus standard gemcitabine (1000mg/m2 weekly). The combination was well tolerated, with no pharmacokinetic interaction. Treatment-emergent toxicities included thrombocytopenia, fatigue, anemia, and edema. The objective response rate was 23% and the disease control rate was 73%. Overall response rate, disease control rate, progression-free survival, and overall survival were higher in patients without detectable KRAS mutations (48% vs. 28%, 81% vs. 69%, 8.8 vs. 5.3months, and 18.2 vs. 6.6months, respectively). Conclusion: Refametinib plus gemcitabine was well tolerated, with a promising objective response rate, and had an acceptable safety profile and no pharmacokinetic interaction. There was a trend towards improved outcomes in patients without detectable KRAS mutations that deserves future investigation. [Figure not available: see fulltext.]

The analysis of subgroups in clinical trials is essential to assess differences in treatment effects for distinct patient clusters, that is, to detect patients with greater treatment benefit or patients where the treatment seems to be ineffective.The software application subscreen (R package) has been developed to analyze the population of clinical trials in minute detail. The aim was to efficiently calculate point estimates (eg, hazard ratios) for multiple subgroups to identify groups that potentially differ from the overall trial result. The approach intentionally avoids inferential statistics such as P values or confidence intervals but intends to encourage discussions enriched with external evidence (eg, from other studies) about the exploratory results, which can be accompanied by further statistical methods in subsequent analyses. The subscreen application was applied to 2 clinical study data sets and used in a simulation study to demonstrate its usefulness.The visualization of numerous combined subgroups illustrates the homogeneity or heterogeneity of potentially all subgroup estimates with the overall result. With this, the application leads to more targeted planning of future trials.This described approach supports the current trend and requirements for the investigation of subgroup effects as discussed in the EMA draft guidance for subgroup analyses in confirmatory clinical trials (EMA 2014). The lack of a convenient tool to answer spontaneous questions from different perspectives can hinder an efficient discussion, especially in joint interdisciplinary study teams. With the new application, an easily executed but powerful tool is provided to fill this gap.

Endometriosis compromises the quality of life of countless women worldwide and is a leading cause of disability. Clinical symptoms of endometriosis can be very heterogeneous leading to a long interval between onset of symptoms and surgical diagnosis. A noninvasive, rapid diagnostic test is urgently needed. In this prospective study, we evaluated the usefulness of Cytokeratin-19 (CK19) as a biomarker for the diagnosis of endometriosis through urine and serum ELISA. 76 reproductive-aged women undergoing laparoscopy for benign conditions were included to this study and divided into two groups by the presence (n = 44) or absence (n = 32) of endometriosis. There was no statistically significant correlation between the concentration of CK19 in urine (p = 0.51) or in serum (p = 0.77) and the diagnosis of endometriosis. Assigning the samples to the proliferative or secretory cycle stage did not sufficiently lower the p values. In this study, the promising data reported in the recent literature about CK19 serving as a sufficient biomarker for endometriosis could not be verified when tested in a larger sample size. Further studies are warranted to explore the usefulness of CK19 in the diagnosis of endometriosis.

A new method is presented which allows the simultaneous detection of various α-dicarbonyl compounds generated in the course of the nonenzymatic browning reaction initiated by thermal treatment of l -ascorbic acid, namely: glyoxal, methylglyoxal, diacetyl, 3-deoxy- l -pentosone, and l -threosone. 3-Deoxy- l -threosone was successfully identified as a new C 4 -α-dicarbonyl structure for the first time in the degradation of Vitamin C by application of this non-chromatographic mass spectrometric approach. Moreover, a more detailed elucidation of the mechanistic scenario with respect to the oxidative and nonoxidative pathways is presented by using dehydro- l -ascorbic acid and 2,3-diketo- l -gulonic acid instead of l -ascorbic acid as a starting material. Furthermore, the postulated pathways are corroborated with the aid of 13 C-isotopic labeling studies. The investigations were extended to baby food, and the successful detection of α-dicarbonyl compounds characteristic for Vitamin C degradation proved the matrix tolerance of the introduced method.

Background: The single hotspot mutation AKT1 [G49A:E17K] has been described in several cancers, with the highest incidence observed in breast cancer. However, its precise role in disease etiology remains unknown.Methods: We analyzed more than 600 breast cancer tumor samples and circulating tumor DNA for AKT1 E17K and alterations in other cancer-associated genes using Beads, Emulsions, Amplification, and Magnetics digital polymerase chain reaction technology and targeted exome sequencing.Results: Overall AKT1 E17K mutation prevalence was 6.3 % and not correlated with age or menopausal stage. AKT1 E17K mutation frequency tended to be lower in patients with grade 3 disease (1.9 %) compared with those with grade 1 (11.1 %) or grade 2 (6 %) disease. In two cohorts of patients with advanced metastatic disease, 98.0 % (n = 50) and 97.1 % (n = 35) concordance was obtained between tissue and blood samples for the AKT1 E17K mutation, and mutation capture rates of 66.7 % (2/3) and 85.7 % (6/7) in blood versus tissue samples were observed. Although AKT1-mutant tumor specimens were often found to harbor concurrent alterations in other driver genes, a subset of specimens harboring AKT1 E17K as the only known driver alteration was also identified. Initial follow-up survival data suggest that AKT1 E17K could be associated with increased mortality. These findings warrant additional long-term follow-up.Conclusions: The data suggest that AKT1 E17K is the most likely disease driver in certain breast cancer patients. Blood-based mutation detection is achievable in advanced-stage disease. These findings underpin the need for a further enhanced-precision medicine paradigm in the treatment of breast cancer.

Sharing pharma compounds with academia: experiences with providing vitamin D receptor ligands

The overall goal of our research is to uncover the linguistic options of expressing negative attitude and experience. To this end, a small corpus of English newsgroup texts about relationship problems and eating disorders, part of the Englische & Deutsche Newsgroup Texte – Annotiertes Korpus (EDNA corpus), has been annotated manually, using Systemic Functional Grammar (Halliday 1994) as theoretical foundation. The EDNA corpus now contains information about Theme-Rheme structure, modality and negative polarity as well as process types, i.e. types of verbs such as action, relational, mental. In this paper, we focus on modality and negative polarity. We start by looking at syntactic negation, both at clause rank (he didn’t love me) and at phrase rank (I will leave, no second chances). In addition, morphological negation will be considered, e.g. That would be unfair. In a second step, the use of epistemic modality (i.e. likelihood of a proposition) and root modality (expressing obligation, inclination or ability) in the EDNA corpus is studied. How do authors position themselves towards their audience and towards what they are saying by using modal auxiliaries (e.g. can, could, may) and modal adjuncts (e.g. certainly, maybe). Following that, we consider how modality and negative polarity combine. In our corpus, as many as 15% of all clauses carry a negative polarity marker, but as many 23% of clauses with a modality marker are also negated. Furthermore, clauses expressing root modality are more likely to be negated than clauses expressing epistemic modality (38% and 15% respectively). Our results suggest that modality markers and negative polarity markers attract each other.

Haplotype sharing analysis is a well-established option for the investigation of the etiology of complex diseases. The statistical power of haplotype association methods depends strongly on how the information of unobserved haplotypes can be captured by multilocus genotypes. In this study we combine an entropy-based marker selection algorithm (EMS), with a haplotype sharing-based Mantel statistics into a new algorithm. Genetic markers are iteratively selected by their multilocus linkage disequilibrium (LD), which is assessed by a normalized entropy difference. The initial marker set is gradually enlarged to increase the available information on the amount of sharing around a potential susceptibility marker. Markers are rejected from joint phasing if they do not increase the multilocus LD. In simulated candidate gene studies, the Mantel statistics combined with the new EMS performs as well or better at detecting the disease single nucleotide polymorphism—or in indirect association analysis its flanking markers—than the Mantel statistics without selection of markers prior to haplotype estimation and the Mantel statistics using sliding windows of size five. It is therefore appealing to apply our selection approach for haplotype-based association analysis, since marker selection driven by the observed data avoids both the arbitrary choice of markers when using a fixed window size, as well as the estimation of haplotype block structure. Genet. Epidemiol. 34: 354–363, 2010. © 2010 Wiley-Liss, Inc.

The results from association studies are usually summarized by a measure of evidence of association (frequentist or Bayesian probability values) that does not directly reflect the impact of the detected signals on familial aggregation. This article investigates the possible advantage of a two-dimensional representation of genetic association in order to identify polymorphisms relevant to disease: a measure of evidence of association (the Bayes factor, BF) combined with the estimated contribution to familiality (the attributable sibling relative risk, λs). Simulation and data from the North American Rheumatoid Consortium (NARAC) were used to assess the possible benefit under several scenarios. Simulation indicated that the allele frequencies to reach the maximum BF and the maximum attributable λs diverged as the size of the genetic effect increased. The representation of BF versus attributable λs for selected regions of NARAC data revealed that SNPs involved in replicated associations clearly departed from the bulk of SNPs in these regions. In the 12 investigated regions, and particularly in the low-recombination major histocompatibility region, the ranking of SNPs according to BF differed from the ranking of SNPs according to attributable λs. The present results should be generalized using more extensive simulations and additional real data, but they suggest that a characterization of genetic association by both BF and attributable λs may result in an improved ranking of variants for further biological analyses.

Background: Mutationally-activated KRAS is present in 90% of pancreatic ductal adenocarcinoma (PDAC) and may represent an early genetic driver, being commonly found in low-grade pancreatic lesions (Eser et al. 2014 BJC 111:817). Refametinib is a potent oral allosteric MEK 1/2 inhibitor with both single-agent activity and synergistic activity in combination with gemcitabine in preclinical models of pancreatic cancer (PC). A Phase 1B/2 study in patients with locally advanced, unresectable or metastatic PC and no prior systemic therapy was conducted and recently reported (Van Laethem et al., ASCO 2014; NCT01251640). We report here on the exploratory biomarker findings from this study. Methods: KRAS mutational analysis was conducted via liquid biopsy at baseline on circulating tumor DNA (ctDNA) by BEAMing (Sysmex-Inostics) as well as circulating micro RNA (miRNA) from plasma collected at baseline and post-dose and analyzed by qPCR using an Exiqon panel of 752 miRNAs and an innovative data preprocessing method for normalization and imputation of undetermined values. Tumor molecular characterization was performed on archival tumor tissue and included targeted tumor gene next-generation sequencing with FOUNDATION ONE and the analysis of Ki67 proliferation index. Results: Samples for biomarker analysis were obtained from 69 treated patients. Forty-six (67%) had detectable KRAS mutations by liquid biopsy. KRAS G12D, G12V and G12R were the most frequent mutations. Interestingly, KRAS wild-type patients had better efficacy outcomes compared to mutant KRAS patients (mut/WT, respectively): overall response rate 15%/30% (OR 2.4, p = 0.147), median progression-free survival (mPFS) 3.7/8.8 mo (HR 0.32, p = 0.001), and overall survival (OS) 7.1/18.2 mo (HR 0.28, p = 0.001). There was a trend correlating KRAS mutant allele frequency with response. The CA19.9 levels correlated with KRAS mutational status. Tumor exome sequencing was performed from 16 patients, 15 of which had a KRAS mutation (G12D or G12V). The discordancy rate compared to BEAMing KRAS data was 26% (4/15). Conclusions: The high prevalence of KRAS mutations in patients with PC has been confirmed using BEAMing technology. In this study, there was an association between improved mPFS and OS in KRAS WT patients. Together with lower baseline levels of CA19.9 in the KRAS WT cohort, we conclude that liquid biopsy may be an approach to identify prognostic or predictive markers in PDAC treated with refametinib and gemcitabine. This hypothesis is sustained by the finding that poor clinical response showed increasing allele frequency of mutant KRAS. These results require confirmation in a larger trial. Citation Format: Michael Teufel, Jean-Luc Van Laethem, Hanno Riess, Marius Giurescu, Vittorio L. Garosi, Anke Schulz, Richardus Vonk, Henrik Seidel, Joachim Reischl, Barrett H. Childs. KRAS wild-type status as detected by circulating tumor DNA analysis may be a prognostic or predictive factor for clinical benefit in patients with unresectable, locally advanced or metastatic pancreatic cancer (PC) treated with the MEK inhibitor refametin [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5239. doi:10.1158/1538-7445.AM2015-5239

The AKT1 (E17K) mutation is rare and occurs in colon, ovarian, lung, and especially breast cancer where its frequency ranges between 1.4% and 8.2%. It's precise role in cancer development and progression in clinical context is still unknown. To increase our understanding of the AKT1 (E17K) mutation in breast cancer we analyzed more than 600 tumor samples from breast cancer patients (UICC I - IV, including untreated and neoadjuvantly treated patients) which were provided by the non-profit organization PATH (Patients’ Tumor Bank of Hope, Germany). Extensive clinical data with a median follow-up time of 4.8 years to record disease progression were available for 95% of the patients included in this study. The AKT1 (E17K) mutation was detected in ∼6% of samples in the analyzed cohort using the BEAMing technology. Correlation with clinical parameters showed that the prevalence of the AKT1 (E17K) mutation was statistically independent of age or post-/pre-menopausal stage and was comparable between HER-2 positive and negative patients. In addition, FOUNDATION ONE® targeted exome Next Generation Sequencing (NGS) analysis of some of the tumor samples was done to demonstrate the fingerprint of individual tumors in correlation with the AKT1 (E17K) mutation. NGS and BEAMing technology had a ∼98% concordance for AKT1 (E17K) mutated and non-mutated samples. In 12 out of 36 AKT1 (E17K) mutated samples no additional somatic mutations (SNVs, indels) described to drive cancer development were detected. Moreover, neither amplification nor deletion of tested genes known to be recurrently amplified or deleted in cancer were found in 10 out of these 12 samples. This supports the hypothesis that AKT1 (E17K) can be a driver mutation. However, in all of these samples mutations with yet unannotated function in additional oncogenes were detected. It remains open whether these aberrations impact the role of AKT1 (E17K) as a driver mutation in tumor growth. Analyses of patient cohort data from large databases, as demonstrated here, holds promise for discovering the role of rare somatic mutations in known oncogenes (such as AKT1 (E17K)) in the development of breast cancer. Citation Format: Marion Rudolph, Tobias Anzeneder, Matthias Ocker, Eleni Lagkadinou, Oliver Politz, Martin Michels, Anke Schulz, Georg Beckmann, Michael Teufel, Henrik Seidel, Richie Soong, Heinz Bodenmüller, Ulla Ohlms, Khusru Asadullah, Joachim Reischl. AKT1 (E17K) mutation: coexistence with oncogenic alterations, prevalence, and correlation to clinical parameter in a large series of breast cancer patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 569. doi:10.1158/1538-7445.AM2014-569

4129 Background: Refametinib is a potent oral allosteric MEK 1/2 inhibitor with both single-agent and synergistic activity in combination with gemcitabine in preclinical models of pancreas cancer (...

4025 Background: Refametinib is a potent oral allosteric MEK 1/2 inhibitor with single-agent and synergistic activities in combination with gemcitabine in preclinical pancreatic cancer (PC) models....