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S.M. Lee
Moderator of
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MO21 - Prognostic and Predictive Biomarkers V - EGFR (ID 98)
- Event: WCLC 2013
- Type: Mini Oral Abstract Session
- Track: Medical Oncology
- Presentations: 12
- Moderators:D.C. Lam, S.M. Lee
- Coordinates: 10/30/2013, 10:30 - 12:00, Bayside Auditorium A, Level 1
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MO21.01 - Randomized Proteomic Stratified Phase III Study of Second Line Erlotinib (E) versus Chemotherapy (CT) in Patients with Inoperable Non-Small Cell Lung Cancer (PROSE): VeriStrat analysis of longitudinal samples (ID 3122)
10:30 - 10:35 | Author(s): A. Bulotta, C. Lazzari, S. Foti, M. Viganò, D. Ghio, S. Novello, S. Barni, M. Aieta, F. Grossi, T. De Pas, F. De Marinis, M. Mencoboni, A. Bearz, J. Roder, H. Roder, J. Grigorieva, I. Floriani, V. Torri, V. Gregorc
- Abstract
- Presentation
Background
2nd-line therapy for advanced NSCLC patients (pts) after progression on platinum-based regimens typically employs CT or E. A test for optimizing choice of treatment in these pts is of clinical value. VeriStrat (VS) is a serum protein test that assigns "good" (VSG) or "poor" (VSP) classification and has demonstrated prognostic and predictive utility. PROSE is a multicenter prospective randomized biomarker validation trial, designed to evaluate the ability of VS to predict survival in 2nd- line NSCLC pts treated with E or CT. As reported at 2013 ASCO1, PROSE met its primary endpoint of demonstrating significant treatment*VS interaction with a p value of 0.031, with VSG pts deriving similar overall survival (OS) benefit from both treatments (hazard ratio (HR) for E=1.06; p=0.71) and VSP pts benefitting more from CT than E (HR for E=1.72; p=0.02). Previous studies in EGFR-TKI-treated pts have shown that at progression around 30% of pre-treatment VSG pts have changed classification to VSP2. The present report discusses the exploratory analysis of longitudinal VS classifications generated during the PROSE study.Methods
Of the 263 pts in the PROSE primary analysis population, 89 provided serum samples during treatment and 108 at progression, with 47 pts providing both. VS testing was performed on these longitudinal samples blinded to all clinical and treatment outcomes and pts and physicians remained blinded to VS results.Results
VSG or VSP classifications were obtained for 89 pts from treatment samples (67 VSG / 22 VSP) and 107 pts (one sample was classified as indeterminate) from progression samples (59 VSG / 48 VSP). In pts with matched baseline and progression samples, the percentage of VSG classifications was lower at progression (55%) than at baseline (77%) (p < 0.001 ). Twenty eight pts (34%) classified at baseline as VSG changed to VSP at progression, in line with previous studies2, and this did not show any significant dependence on treatment. When treated with E, pts whose classification changed from VSG at baseline to VSP during treatment (n=6) had inferior PFS to the 25 pts who remained VSG (p=0.001, median PFS: 3.6 and 7.7 months (mos), respectively). Patients whose classification changed from VSG at baseline to VSP at progression on E (n=18) had numerically inferior OS (median 10.0 mos) compared with the 31 pts who remained VSG at progression (median 14.6 mos) and significantly superior OS (median 5.0 mos) compared with the 10 pts who were VSP at both time points (p<0.001).Conclusion
The observed changes in VS classification at progression demonstrate the importance of obtaining a VS result prior to each line of therapy for which erlotinib is considered as a therapeutic option. The proportion of patients who are good candidates for erlotinib therapy (VSG) decreases from 2[nd] to 3[rd] line and the possible impact of this on treatment sequencing and monitoring for 2[nd] and higher line advanced NSCLC pts merits further studies.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.02 - Pretreatment evaluation of the T790M mutation and its correlation with the response to tyrosine kinase inhibitors (TKIs) or chemotherapy in advanced non-small cell lung cancer (NSCLC) patients with activated EGFR mutations (ID 2455)
10:35 - 10:40 | Author(s): F. Grossi, M.G. Dal Bello, E. Rijavec, C. Sini, C. Genova, G. Barletta, C. Defferrari, S. Coco, A. Truini, A. Alama, S. Zupo, M. Dono
- Abstract
- Presentation
Background
Preclinical data have shown that the EGFR-T790M mutation confers resistance to reversible EGFR-TKIs (gefitinib, erlotinib) but not to irreversible EGFR-TKIs (afatinib). This study evaluated advanced NSCLC patients (pts) harboring an activated EGFR mutation (exon 18-21) to investigate the incidence of the T790M mutation in pretreatment tumor samples and the correlation between the T790M mutation and the clinical outcome, comparing patients positive for the T790M mutation treated with reversible TKIs, an irreversible TKI or chemotherapy to patients negative for the T790M mutation treated with the same agents.Methods
We screened 317 advanced NSCLC pts for EGFR mutations using the PCR/Sanger sequencing (PSS) method. Tumor tissues from EGFR-mutated pts were analyzed for the EGFR-T790M mutation using a highly sensitive locked nucleic acid-PSS method (LNA-PSS) capable of detecting EGFR-T790M-mutated alleles at extremely low frequencies. The response rate (RR), progression-free survival (PFS) and overall survival (OS) were evaluated retrospectively in these pts.Results
Using PSS, 17.3% (55/317) of pts had an activating mutation in the EGFR-TK domain; 56.3% (31/55) of pts had an in-frame deletion in exon 19, 32.7% (18/55) of pts had point mutation L858R in exon 21, 3.6% (2/55) of pts had an insertion in exon 20, and 7.2% (4/55) of pts had both the T790M mutation and either an exon 19 or 21 mutation. Forty-two pts with EGFR-activating mutations (82.3%) without the T790M mutation (by PSS) were successfully analyzed for the T790M mutation using LNA-PSS. The T790M mutation was detected in 17 (40.5%) pts, with a higher incidence in never smokers (47.7%), adenocarcinoma (76.2%) and females (71.4%). A treatment response evaluation was available in 39 pts, 18 of whom (46.1%) harbored the T790M mutation. Pts with T790M had a lower RR (22.2%) to TKIs than wild-type pts (35.3%); however, mutated pts had better PFS and OS (median PFS 9.2 vs 7 months, respectively; median OS 15.2 vs 11.1 months, respectively). Pts treated with afatinib and positive for T790M obtained longer PFS compared to pts negative for T790M (median PFS 4.7 vs 3.2 months, respectively), but their OS was shorter (median OS, 16.3 vs 18.2 months, respectively). Notably, pts with the T790M mutation had a greater response to chemotherapy (44.4%) compared to pts without the mutation (18.2%) and had a longer PFS (median PFS 8.2 vs 6.1 months, respectively) and OS (median OS 21.8 vs 12.4 months, respectively).Conclusion
In this study, the high proportion of pretreatment tumor samples positive for the EGFR-T790M mutation indicates that its identification at diagnosis is more common than expected using a highly sensitive method. Consequently, in NSCLC pts with EGFR-activating mutations, detection of the T790M mutation at diagnosis can help customize therapy and identify a subset of patients with a relatively more favorable prognosis.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.03 - Variability of epidermal growth factor receptor (EGFR) mutations in serum during erlotinib therapy and its clinical implications: exploratory analysis of a phase II study of erlotinib in patients with advanced non-small-cell lung cancer (NSCLC) harboring EGFR mutations (ID 2719)
10:40 - 10:45 | Author(s): M. Maemondo, M. Nishio, N. Yamamoto, K. Chikamori, N. Katakami, T. Hida, T. Seto, H. Yoshioka, T. Kozuki, N. Ohishi, T. Tamura
- Abstract
- Presentation
Background
Erlotinib is a standard treatment for NSCLC patients harboring EGFR mutations. Many tumors acquire resistance mutations during erlotinib treatment; consequently, confirmation of EGFR mutation status is important to select appropriate subsequent therapy after progression. Obtaining tumor samples is not easy, therefore, serum samples are more applicable for this purpose. This analysis measured serum EGFR mutations before and after administration of erlotinib in a phase II study in Japanese chemotherapy-naïve patients with advanced NSCLC harboring EGFR mutations (JO22903).Methods
We analysed serum samples from patients in the JO22903 study by Scorpion-ARMS to confirm the presence of EGFR mutations before and after erlotinib administration (190 days post treatment initiation and at disease progression). The mutation results were evaluated in relation to clinical characteristics and effects of erlotinib.Results
Of the 103 patients registered in JO22903, 95 consented to the examination of EGFR mutations in serum samples prior to and following administration of erlotinib. Of these 95 patients, 26 were positive for EGFR mutations (16 were exon 19 deletions, nine were exon 21 L858R mutations, one was an exon 20 S768I mutation). In the 26 patients classed as EGFR mutation-positive in serum samples, the concordance rate between tumor samples and serum samples was 96.2% (matching 25 cases except the S768I mutation case). The EGFR mutation detection rate in serum samples prior to erlotinib administration was 35.6% for exon 19 deletions (16/45) and 18.0% for L858R mutations (9/50). In six cases where exon 20 T790M or minor mutations were detected alongside major mutations in tumor samples, the major mutations were detected in corresponding serum samples of four patients but the T790M mutations or minor mutations were not detected in any serum samples. In the 65 cases in which serum samples were taken 190 days after erlotinib administration, five were positive for EGFR mutations (exon 19 deletions in four, and L858R in one). Four of these cases were consistent with the mutation type of the tumor samples taken before erlotinib administration; one case changed from L858R to exon 19 deletion. Serum samples at disease progression were taken for 72 patients. Of these, 16 were positive for EGFR mutations (three were exon 19 deletions, five were exon 19 deletions + T790M, six were L858R and two were L858R + T790M). EGFR mutation type had changed after administration of erlotinib in three cases; these cases also had multiple metastases. Characteristics of EGFR mutation-positive cases in the pre-treatment serum samples were large tumor size, and metastases to other organs (bone, brain, liver). Patients with baseline serum EGFR mutations had median PFS of 9.7 months and those without baseline serum EGFR mutations had median PFS of 15.2 months. Further efficacy results will be presented.Conclusion
The sensitivity of these analyses was not enough to draw firm conclusions; however, results show the possibility that serum EGFR mutations correlate with disease activity and emergence of resistance mutations. Further study is recommended to measure serum EGFR mutations throughout the treatment course, to ascertain whether this can predict the risk of disease progression.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.04 - Prognostic and Therapeutic Implications of the Aromatase Expression in Lung Adenocarcinoma Harboring EGFR Mutation (ID 2242)
10:45 - 10:50 | Author(s): M. Kohno, T. Okamoto, K. Suda, Y. Suzuki, T. Fujishita, S. Shimamatsu, H. Kitahara, T. Yoshida, Y. Morodomi, D. Kawano, T. Yano, Y. Maehara
- Abstract
- Presentation
Background
A significantly greater proportion of females and adenocarcinoma patients is found in never-smoking NSCLC groups than in smoking NSCLC groups. Recent studies have demonstrated that estrogens may contribute to the carcinogenesis and development of lung carcinoma. In the present study, we investigate the correlation between the expression of aromatase (CYP19-1) and clinicopathologic factors and assess the prognostic significance of the aromatase expression in patients with primary lung adenocarcinoma.Methods
The aromatase mRNA expression levels in the primary tumors and corresponding nonneoplastic lung specimens of 110 Japanese patients who underwent complete resection for primary lung adenocarcinoma were evaluated using quantitative RT-PCR. The relationships between the aromatase expression and clinicopathologic factors or survival were analyzed. To test the growth inhibitory effects of the aromatase inhibitor exemestane alone and in combination with the EGFR-TKI erlotinib in vitro, the cell proliferation of the lung adenocarcinoma cell lines HCC4006 and 11-18 was measured according to the WST-8 method.Results
The mRNA expression level of aromatase in the carcinoma tissues was significantly higher than that in the corresponding normal lung tissues (P = 0.013). The aromatase expression in the lung adenocarcinoma tissues was not correlated with the clinicopathologic factors, including patient gender, age, smoking status, EGFR mutation status or pathologic stage. A high aromatase expression was associated with a poor prognosis in terms of both the recurrence-free survival (RFS) (P = 0.004) and overall survival (OS) (P = 0.003). A multivariate analysis showed that the aromatase expression was a significant prognostic factor, with a relative risk of 2.35 (P = 0.043) for RFS and 5.19 (P = 0.004) for OS. We further stratified the population according to gender, smoking status and EGFR mutation status. A high aromatase expression was related to a poor prognosis in femles (RFS; P = 0.008, OS; P < 0.001), never-smokers (RFS; P = 0.009, OS; P < 0.001) and patients with EGFR mutations (RFS; P = 0.005, OS; P = 0.003). A multivariate analysis showed that the aromatase expression was a significant prognostic factor, with a relative risk of 5.22 (P = 0.013) for RFS in the patients with EGFR mutations. HCC4006, harboring an EGFR mutation with a low aromatase mRNA expression, was not sensitive to exemestane alone or combination with erlotinib. In contrast, 11-18, harboring an EGFR mutation with a high aromatase mRNA expression, was sensitive to exemestane alone. In addition, cell growth was significantly inhibited by the combination of exemestane and erlotinib.Conclusion
A high expression of aromatase is correlated with a poor outcome in patients with lung adenocarcinoma, especially those harboring EGFR mutations. Aromatase may be a therapeutic target in lung adenocarcinoma with a high aromatase expression and with an EGFR mutation.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.05 - Integrated genomic analysis by whole exome and transcriptome sequencing of tumor samples from EGFR-mutant non-small-cell lung cancer (NSCLC) patients with acquired resistance to erlotinib. (ID 1426)
10:50 - 10:55 | Author(s): T. Bivona, P. Gianikopoulos, C. Costa, N. Karachaliou, J. St. John, M. Wilkerson, A.F. Cauhlin, O. Westesson, N. Boley, N. Hahner, U. Parikh, M.D. Lozano, S. Viteri, J.L. Perez-Gracia, A. Curioni, E. Jantus-Lewintre, C. Camps, A. Vergnenegre, R. Gervais, A. Wellde, J. Barry, G.W. Wellde Jr., A.F. Cardona, R. Stahel, W.R. Polkinghorn, R. Rosell, J. Weissman
- Abstract
- Presentation
Background
NSCLC patients with EGFR mutations initially respond to EGFR tyrosine kinase inhibitors (TKIs) but ultimately relapse. Sub-genomic molecular studies indicate that the EGFR T790M mutation and the activation of MET, PI3K, AXL, HER2 and MAPK can lead to acquired resistance to EGFR TKIs. To date, no integrated comprehensive genomic investigation of EGFR TKI resistance has been reported.Methods
FFPE biopsies of erlotinib-sensitive and erlotinib-resistant tumors were obtained from 13 EGFR mutant NSCLC patients. The samples were analyzed by whole exome sequencing and whole transcriptome sequencing utilizing the Illumina HiSeq2500 platform. In addition, targeted gene sequencing was performed with the Illumina TruSeq Amplicon-Cancer Panel and run on the MiSeq system.Results
Erlotinib resistant NSCLC specimens harbored known resistance drivers, including EGFR T790M mutations (9/13; 69%), MET amplification (3/13; 23%), HER2 amplification (3/13; 23%), and AXL upregulation (3/13; 23%). Differential expression analysis between resistant and pre-treatment states revealed enrichment in the pre-treatment tumors of immune signaling pathways, and in the resistant tumors upregulation of ERBB2, mTOR, PI3 kinase and ribosomal signaling pathways. PI3K/AKT pathway upregulation also occurred through somatic mutations in AKT and LKB1 in the resistant tumors. Copy number analysis demonstrated both large scale and focal amplifications and deletions in the resistant tumors, including the focal loss of EGFR and gain of c-Myc and NKX2-1. There was strong correlation between the copy number changes observed and the expression mRNA levels of the involved cancer-associated genes. Of note, each resistant tumor exhibited greater copy number similarity to the corresponding matched pre-treatment sample compared to other tumors within the resistance cohort.Conclusion
We conducted the first ever comprehensive integrated genomic analysis of EGFR TKI resistant NSCLC patients, and identified both known and potentially novel drivers of EGFR TKI resistance. This study demonstrated the feasibility and utility of comprehensive genomic analysis in the clinical management of NSCLC receiving targeted therapy. Together, our data provide unprecedented insight into the molecular pathogenesis of escape from EGFR oncogene inhibition in NSCLC. We are now conducting a prospective observational study in additional NSCLC patients on targeted therapy.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.06 - DISCUSSANT (ID 3917)
10:55 - 11:10 | Author(s): J.C. Yang
- Abstract
- Presentation
Abstract not provided
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MO21.07 - Monitoring of EGFR TKI sensitizing and resistance mutations in plasma DNA of advanced adenocarcinoma of NSCLC during erlotinib treatment. (ID 2168)
11:10 - 11:15 | Author(s): B. Sorensen, L. Wu, W. Wen, J. Tsai, B. Weber, E. Nexo, P. Meldgaard
- Abstract
- Presentation
Background
EGFR TKI sensitizing mutations in plasma DNA isolated prior to treatment were shown to be a potent predictor for survival outcome of advanced NSCLC (T. Mok, ASCO 2013). Levels of EGFR mutations (pEGFRmut) in plasma during treatment, including sensitizing and resistance mutations, may offer an opportunity to monitor patient’s response to therapy and disease progression. In this study, we measured the levels of pEGFRmut at every 4 weeks during erlotinib treatment and investigated the emergence of the T790M mutation in relationship to disease progression.Methods
Retrospective EGFR mutation testing of plasma samples from an unselected cohort of 227 patients with adenocarcinoma with an allele-specific PCR assay, cobas® EGFR_blood test (in development at Roche Molecular Systems, Inc.). The test is designed to detect 42 mutations in exon 18-21 of the EGFR gene including TKI sensitizing mutations (Exon 19 deletions, L858R, G719X and L861Q), resistance mutation (T790M) and atypical mutations (S768I and Exon 20 Insertions). 2 ml plasma of each patient was used for EGFR_blood PCR test. The genomic equivalent copy number of plasma DNA was determined by comparing to a standard curve of genomic DNA.Results
25 (11%) of 227 unselected patients with adenocarcinoma had a sensitizing EGFR mutation in their plasma prior to the erlotinib treatment. Sequential plasma samples were retrieved for 23 of the 25 pEGFRmut+ patients. 22 (96%) of the 23 pEGFRmut+ patients had lower TKI sensitizing mutations after the first cycle (4 weeks) of erlotinib treatment. The mutated DNA was reduced below the limit of detection for 13 (57%) of the 23 pEGFRmut+ patients during the course of erlotinib treatment. At the time of progression, 6/23 had the same EGFR sensitizing mutations, 9/23 developed T790M mutation with the original mutation and 6/23 patients had no detectable mutation. T790M mutation was not detected in 227 plasma samples taken prior to erlotinib treatment. The figure shows the time course of two representative patients where a T790M resistance mutation emerges. In the 9 patients with T790M mutation, it can be detected in the blood between 15 and 344 days (mean of 98 days) before progression is clinically evident.Figure 1Conclusion
The amounts of EGFR TKI sensitizing mutant DNA in plasma change during the erlotinib treatment. T790M mutation was not detected prior to erlotinib treatment and is detected between 15 and 344 days before disease progression is evident.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.08 - Detection of EGFR mutations in plasma and diagnosis biopsies from non-small cell lung cancer patients using allele-specific PCR assays. (ID 2248)
11:15 - 11:20 | Author(s): B. Weber, P. Meldgaard, H. Hager, L. Wu, J. Tsai, W. Wen, A.A. Khalil, E. Nexo, B. Sorensen
- Abstract
- Presentation
Background
EGFR TKI sensitizing mutations from plasma prior to treatment were shown to be a potent predictor for survival outcome of advanced NSCLC (T. Mok, ASCO 2013). In this study, we tested EGFR mutations in the archived plasma from 199 advanced adenocarcinoma. The plasma samples were taken when they progressed on their chemotherapy and before their 2nd erlotinib treatment a mean of 10.5 months after the diagnostic biopsy was obtained. EGFR mutations detected in plasma after chemotherapy and in the tumor DNA from their original diagnostic biopsies were also compared.Methods
Plasma DNA and tumor DNA were tested with two allele-specific PCR assays, cobas® EGFR_ FFPET tissue test and cobas® EGFR_blood test (in development at Roche Molecular Systems, Inc.). Both allele-specific PCR assays detect 41 mutations in exon 18-21 of the EGFR gene including TKI sensitizing mutations (Exon 19 deletions, L858R and G719X), resistance mutation (T790M) and atypical mutations (S768I and Exon 20 Insertions). cobas® EGFR_blood test also detects L861Q. Plasma samples of all 199 adenocarcinoma were collected immediately (less than 2 days) prior to the patient’s erlotinib treatment and stored at -80°C. From 197 (99%) of 199 of the patients tumor DNA was extracted from the diagnostic biopsy.Results
Among 199 advanced adenocarcinoma patients, 24/199 (12%) were EGFR mutation positive in plasma. 28/196 (14%) were EGFR mutation positive in tumor DNA. The comparison of EGFR mutation in plasma and tumor DNA is shown in the table 1. The overall concordance of EGFR mutation status in plasma and tumor biopsy was 91% (179/196). 17/196 (9%) patients had the same EGFR mutations in plasma as in their original diagnosis biopsy and 162/196 (82%) patients were mutation negative in both samples. In this study, different EGFR mutation status in plasma and original biopsy was observed in 17 of 196 (9%) patients. 6 of 17 were EGFR mutation positive in plasma only and 11 of 17 were EGFR positive in tumor DNA only. These differences could reflect alterations in the tumor cells between sampling of biopsy and blood (average of 10.5 months) where the patients are treated with chemotherapy. Another possibility is limitations of assay technology with circulating cell-free DNA in plasma or heterogeneity of tumor.Conclusion
Tumor mutations in the patient’s original diagnostic biopsy can be detected in their plasma when they progress on chemotherapy which may provide another opportunity for mutation testing. Table 1. Comparison of EGFR mutations detected in plasma and diagnostic biopsy. MND=Mutation-Not-Detected.Figure 1Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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- Abstract
- Presentation
Background
Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in advanced non-small cell lung cancer patients (NSCLC) is attributed to the T790M mutation of EGFR. Here, we evaluated T790M mutation using dynamic, quantitative and non-invasive method and explored its role predicting outcomes of EGFR-TKI treatment.Methods
We enrolled 135 EGFR-TKI-resistant NSCLC patients in the study. Pre- and post-EGFR-TKI treatment (pre-TKI and post-TKI, respectively) plasma samples were obtained for analysis. T790M mutation was measured qualitatively and quantitatively by the amplification refractory mutation system (ARMS) and digital polymerase chain reaction (D-PCR).Results
D-PCR was more sensitive than ARMS in detecting the T790M mutation (pre-TKI: 29.4% (32/109) vs 5.5% (6/109), P<0.001; post-TKI: 43.0% (58/135) vs 25.2% (34/135), P=0.001). Patients with a pre-TKI T790M mutation (N=32) showed shorter progression free survival (PFS) and overall survival (OS) than patients without a T790M mutation (N=77) (9.2 vs 12.7 months, P=0.004; and 19.3 vs 31.9 months, P=0.001, respectively). No differences were observed in post-TKIPFS or OS (12.5 vs 12.2 months, P=0.744; and 27.0 vs 29.7 months, P=0.636, respectively). Post-treatment patients were divided into high-frequency (>4.375%) and low-frequency (≤4.375%) groups, according to the mutant T790M-to-wild-type gene ratio calculated from D-PCR results. Patients in the high-frequency group showed a significantly shorter OS than the low-frequency group (20.67 vs 29.13 months, P=0.009).Conclusion
D-PCR is more sensitive than ARMS in detecting the T790M mutation. The presence of a pre-TKI T790M mutation and a high frequency of post-TKI T790M mutation predicted poor outcomes of EGFR-TKI treatment.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.10 - Serial monitoring of plasma EGFR T790M levels and evaluation of EGFR mutational status in matched tissue and plasma from NSCLC patients treated with CO-1686 (ID 2498)
11:25 - 11:30 | Author(s): H.A. Wakelee, C.A. Karlovich, W. Wen, J. Sun, S. Chien, E. Mann, P. O'Donnell, P. Angenendt, R. Dziadziusko, L. Horn, D. Spigel, L.V. Sequist, B. Solomon, J. Soria, D..R. Camidge, J. Goldman, S. Gadgeel, M. Raponi, L. Wu, K. Park
- Abstract
- Presentation
Background
Background: We explored the minimally-invasive detection of EGFR mutations in circulating free DNA from plasma and studied the concordance of EGFR mutation status between matched plasma and tumor tissue in a cohort of newly diagnosed or relapsed patients with advanced NSCLC. CO-1686 is an oral, potent, small-molecule irreversible tyrosine kinase inhibitor that selectively targets mutant forms of EGFR, including T790M and the common initial activating mutations, while sparing wild-type EGFR. Promising clinical activity has recently been reported from an on-going Phase I/II trial.Methods
Methods: Matched tumor tissue and blood from 80 Stage IIIB/IV NSCLC patients, 41 treated with CO-1686, were tested using two allele-specific PCR assays, the cobas® EGFR FFPET and cobas® EGFR blood tests. Each test detects 41 mutations in EGFR, including the T790M resistance mutation, exon 19 deletions and L858R. We also used BEAMing, a highly quantitative and sensitive technology based on digital PCR, to assess a subset of 18 patients treated with CO-1686. BEAMing was compared to cobas analysis at baseline, and also used to serially monitor plasma EGFR mutation levels in response to CO-1686.Results
Results: Using tissue as reference, the positive percent agreement between tissue and plasma was 76% (44/58) for activating mutations and 63% (17/27) for T790M. The cobas® EGFR blood test identified two patients with T790M mutations in plasma that were not detected in the corresponding tumor biopsy—likely because of tumor heterogeneity. The M1a/M1b status was known for 63 EGFR mutation-positive patients. Of the 44 with extrathoracic metastatic disease (M1b), 38 were found to have an activating mutation in plasma (86%). Conversely, only 53% (10/19) of EGFR mutation-positive patients with intrathoracic metastatic disease (M1a) had detectable activating mutations in plasma (p = 0.0081). For the 18 patients profiled by BEAMing, the overall percent agreement between BEAMing and the cobas® EGFR blood test was 94% (17/18) for T790M and 83% (15/18) for activating mutations. Nine of the 18 patients had detectable baseline plasma T790M levels, and several patients treated with CO-1686 had an initial decrease in plasma T790M by BEAMing.Conclusion
Conclusions: Using the cobas® EGFR blood test, a high proportion of EGFR mutations identified in tissue were also detected in plasma. Mutations were more readily detectable in the plasma of patients with M1b rather than M1a disease. These findings suggest that the cobas® EGFR blood test and BEAMing can be useful tools for the non-invasive assessment and monitoring of EGFR mutations in NSCLC patients.EGFR mutation Evaluable patients Patients with tissue mutations* Patients with plasma mutations** Patients with same mutation detected in tissue and plasma Positive Percent Agreement*** L858R, del19, S768I, G719X, or ex20ins 80 58 44 44 76% T790M 80 27 19 17 63% * identified by the cobas® EGFR tissue test ** identified by the cobas® EGFR blood test ***agreement of blood and tissue mutation-positive results with tissue as reference; although tissue is reference, some mutations may be missed due to tumor heterogeneity Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO21.11 - DISCUSSANT (ID 3918)
11:35 - 11:50 | Author(s): G.R. Oxnard
- Abstract
- Presentation
Abstract not provided
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MO21.12 - AZD9291: an irreversible, potent and selective tyrosine kinase inhibitor (TKI) of activating (EGFRm+) and resistance (T790M) mutations in advanced NSCLC (ID 2289)
11:30 - 11:35 | Author(s): M. Ranson, W. Pao, D. Kim, S. Kim, Y. Ohe, E. Felip, D. Planchard, S. Ghiorghiu, M. Cantarini, D. Cross, P.A. Jänne
- Abstract
- Presentation
Background
The first generation EGFR TKIs gefitinib and erlotinib provide significant clinical benefit in patients with advanced EGFR mutant NSCLC but many patients ultimately develop disease progression due to acquired resistance. The EGFR T790M mutation is the most common mechanism of acquired drug resistance, detected in more than 50% of gefitinib/erlotinib resistant patients. Current therapeutic strategies are limited for NSCLC patients with EGFR T790M.Methods
AZD9291 is an oral, irreversible, third generation inhibitor of both EGFR activating (EGFRm+) and resistance mutations (T790M). The mechanistic and functional activity of AZD9291 was characterised in vitro across a number of cell lines harbouring various EGFR-mutations or wild type EGFR. Efficacy of AZD9291 was further evaluated across a number of different EGFR-mutant xenograft and transgenic models in vivo. One open label, dose escalation phase I study of AZD9291 (NCT01802632) is ongoing to determine the safety and tolerability [primary measure], pharmacokinetics and preliminary efficacy profiles of AZD9291, in patients with advanced NSCLC who have progressed following EGFR TKI. Sequential cohorts of 3-6 patients with advanced NSCLC who have had at least one prior regimen containing an EGFR TKI agent (with confirmed EGFRm+ status or Jackman criteria), were treated with AZD9291 once daily. Other key inclusion criteria were PS 0-1, measurable disease, and no prior history of ILD. RECIST assessments were scheduled 6 weekly. Dose escalation can occur after ≥ 3 patients complete both single dose and the first 21-day cycle of AZD9291 multiple dosing with no DLT.Results
AZD9291 potently inhibits EGFR phosphorylation in EGFRm+ (PC9; 14nM) and EGFRm+/T790M (H1975; 13nM) cell lines in vitro, whilst demonstrating much less activity against wild-type EGFR lines (LoVo; 400nM). Consistently, AZD9291 showed significantly more potent inhibition of proliferation in mutant EGFR cell lines compared to wild-type in vitro. In addition, AZD9291 treatment caused profound growth regression across multiple EGFRm+ (PC9; 250% growth inhibition) and EGFRm+/T790M (H1975; 132% growth inhibition) tumour models in vivo, at doses as low as 5mg/kg after 14 days. Tumour growth inhibition was associated with profound inhibition of EGFR activity and key downstream signaling pathways. Chronic long-term treatment of in vivo PC9 and H1975 xenograft tumours with AZD9291 led to a complete and sustained macroscopic response. In the phase I study, clinical activity with RECIST responses have already been observed at the starting dose level of 20mg once daily, with good tolerability, no reported events of EGFR wild-type rash, and only grade 1 diarrhoea (based on preliminary data, unvalidated and subject to change).Conclusion
Preclinical data demonstrates that AZD9291 is a potent and effective inhibitor of both EGFR activating (EGFRm+) and resistance mutations (T790M) whilst sparing wild-type EGFR and, early clinical data have been promising. Taken together, these data support the further clinical investigation of AZD9291 in advanced EGFR mutant NSCLC.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
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MO07 - NSCLC - Targeted Therapies II (ID 114)
- Event: WCLC 2013
- Type: Mini Oral Abstract Session
- Track: Medical Oncology
- Presentations: 1
- Moderators:T. John, J.W. Riess
- Coordinates: 10/28/2013, 16:15 - 17:45, Bayside Auditorium B, Level 1
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MO07.11 - A randomised placebo-controlled multicentre phase II trial of erlotinib plus whole brain radiotherapy for patients with advanced non-small cell lung cancer with multiple brain metastases (TACTIC) (ID 2305)
17:15 - 17:20 | Author(s): S.M. Lee
- Abstract
- Presentation
Background
Median survival of non-small cell lung cancer (NSCLC) patients with brain metastases is poor. We examined concurrent erlotinib and whole brain radiotherapy (WBRT) followed by maintenance erlotinib in patients with untreated brain metastases, given the potential radiosensitising properties of erlotinib and its direct effect on brain metastases and systemic activity.Methods
Eighty NSCLC patients with KPS≥70 and multiple brain metastasis were randomised to placebo (n=40) or erlotinib (100mg, n=40) given concurrently with WBRT (20 Gy in 5 fractions). Following WBRT, patients continued with placebo or erlotinib (150mg) until disease progression. The primary end-point was neurological progression-free survival (nPFS).Results
Fifteen patients (37.5%) from each arm were alive and without neurological progression 2 months after WBRT. Median nPFS was 1.6 months in both arms; nPFS HR 0.95 (95% CI, 0.59-1.54; p=0.84). Median overall survival (OS) was 2.9 and 3.4 months in the placebo and erlotinib arms; HR 0.95 (95% CI, 0.58-1.55; p =0.83). The frequency of EGFR mutations was low with only 1 out of 35 (3%) patients with available samples had activating EGFR-mutations. Grade 3/4 adverse event rates were similar between the two groups (70% in each arm), except for rash 20% (erlotinib) vs. 5% (placebo), and fatigue 17% vs. 35%. No significant QoL differences were found.Conclusion
Our study showed no advantage in nPFS or OS for concurrent erlotinib and WBRT followed by maintenance erlotinib in patients with predominantly EGFR wild-type NSCLC and multiple brain metastases. Future studies should focus on the role of erlotinib with or without WBRT in patients with EGFR mutations.Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
