2nd Generation Tyrosine Kinase Inhibitors Research Articles

Abstract 1598: EGFR mutational detection in vortex-enriched CTCs, ctDNA, and comparison to tumor tissue in non-small cell lung cancer (NSCLC) patients

Abstract Background Lung cancer is the leading cause of cancer-related mortality worldwide and 85% cases are NSCLC. Epidermal growth factor receptor (EGFR) mutations occur in 10-30% of NSCLC patients1. EGFR tyrosine kinase inhibitor (TKI) therapies, based on the evaluation of EGFR mutation, have shown dramatic clinical benefits. EGFR assays are mainly performed on tumor biopsies, which carry risks and expense and are not always successful1. In order to identify the development of secondary EGFR mutations, which cause resistance to 1st and 2nd generation TKI's and an indication for therapy with a 3rd generation drug, effective and non-invasive monitoring is needed. Liquid biopsies containing circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA), allow such monitoring over the course of the therapy2. The Vortex Biosciences' VTX-1 Liquid Biopsy System enables the label-free capture of CTCs from blood samples, with high CTC recovery, purity and compatibility with downstream genomic assays on CTCs and plasma3,4. Our combined CTC and ctDNA EGFR assay was applied to blood samples from NSCLC patients. Method ctEGFR kit (EntroGen) was selected and validated for the detection of EGFR major mutations in a single PCR reaction, for both ctDNA and CTCs. Several blood collection tubes (BCT: EDTA, CellSave, LBGard and Streck) were tested using spiked cells, considering CTC recovery, DNA yield, and EGFR profiling. 20 blood samples were studied from 15 NSCLC patients. Plasma was extracted for ctDNA assay. CTCs were isolated from the plasma-depleted-blood using the VTX-1, immunostained and enumerated5. EGFR mutations were then detected in CTC+ctDNA, and compared to the tissue results. Results The VTX-1 provided a similar CTC recovery from plasma-depleted-blood and whole blood, enabling CTC+ctDNA EGFR profiling from the same tube of blood. Among the BCTs tested, LBGard obtained the best CTC capture and EGFR mutation detection performance. 10/15 patients showed the same mutations between tissue and CTC+ctDNA. For one patient with two blood draws without mutation in tissue, no mutation was detected in the first draw, while a T790M mutation was identified 6 months later. For another patient, an Exon19 deletion was detected in the ctDNA+CTC but not in the tissue, and a repeat draw confirmed the result. 4/15 patients had mutations in tissue that were missed in CTC+ctDNA. Conclusion Performing EGFR mutation analysis on the combination of ctDNA and VTX-1-collected CTCs may offer an improved sensitivity of detection over analysis of only the ctDNA, and will be potentially a useful tool for monitoring treatment and medication guidance of NSCLC patients. [1] Calabuig-Fariñas et al. Transl Lung Cancer Res. 2016. [2] Sundaresan TK et al. Clin Cancer Res. 2016. [3] Kidess-Sigal E et al. Oncotarget 2016. [4] Haiyan E L et al. npj Genomic Medicine (2017) 2:34. [5] Che J. et al., Oncotarget (2016) Citation Format: Elodie Sollier-Christen, Haiyan E. Liu, Meghah Vuppalapaty, Michael Chiu, James Che, Charles Wilkerson, Nasim Barzanian, Steve Crouse, James Carroll, Melissa Matsumoto, Edward B. Garon, Jonathan W. Goldman. EGFR mutational detection in vortex-enriched CTCs, ctDNA, and comparison to tumor tissue in non-small cell lung cancer (NSCLC) patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1598.

Abstract 1835: PPARγ agonist in combination with bcr/abl tyrosine kinase inhibitors in patients of chronic myeloid leukemia in chronic phase with suboptimal molecular response

Abstract Introduction & background: Ten to 20 % of patients of Chronic Myeloid Leukemia in chronic phase (CML CP) have suboptimal molecular response (MR) to first line Imatinib maleate (IM). Treatment options include IM dose increase or switch to a 2nd generation tyrosine kinase inhibitor (TKI), Nilotinib or Dasatinib. Recently, synergy has been demonstrated when PPAR γ agonists are added to TKIs. We describe our initial results on 15 patients of CML CP treated with the combination of IM and pioglitazone, a PPAR γ agonist. Patients and methods: Fifteen patients of CML CP with suboptimal MR (bcr/abl:abl RQ-PCR between 1 to 10) after more than two years of IM were recruited in this pilot study. Because of economic considerations, these patients were not candidates for 2nd gen. TKIs. Patients given IM 600 mg/day and pioglitazone 30 mg/day. Blood counts and biochemistry monitored monthly, bcr/abl tested every 3 months using a cartridge based IS assay using the Cepheid GenXpert. Results & conclusions: Twelve of the 15 patients achieved significant MR, with 6/16 achieving a major MR at 9 months. Only 3/15 did not show a response (Table). Treatment with pioglitazone was well tolerated. One patient was not analysed due to intolerance to pioglitazone are first dose. Two patients had grade 1 elevation of hepatic enzymes which returned to normal after one week treatment cessation. We conclude that the combination of imatinib with pioglitazone is effective and well tolerated in patients with a sub-optimal MR to TKI in patients with CML-CP. The combination could be a cost-effective strategy in treating imatinib non/sub-optimal responders in the developing world. The combination needs further and larger studies for confirmation and evaluation of the mechanisms of the synergy. S. No.Patient ID/SexDiagnosis dateBCR-ABL (Before Pio)BCR-ABL (After Pio)At 3 monthAt 6 monthAt 9 month1SCM/MOct 20125.352.741.830.0052MD/FAug 20061.130.880.480.13GPJ/MJan 20142.860.43ND0.54RRC/MOct 20082.861.070.25ND5RK/MMar20081.390.770.350.416RDS/FOct 200010.15.994.870.677RDR/FApril 20039.045.780.360.058MM/MMay 20114.48NDND0.149RD/FJuly 20108.331.290.440.7310RB/FJuly 20153.253.022.891.3911BRR/MJan 20107.135.613.821.7712BK/FNov 20042.060.040.030.0713DPS/MJan 20116.155.471.020.8414JKM/MApril 20074.2215.49.117.6215CS/MOct 20121.721.170.840.08 Citation Format: Hemant Malhotra, Ajay Yadav, Ashwin Mathur, Debashish Biswas, Bharti Malhotra. PPARγ agonist in combination with bcr/abl tyrosine kinase inhibitors in patients of chronic myeloid leukemia in chronic phase with suboptimal molecular response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1835.

New possibilities in the treatment of EGFR mutation-positive non-small-cell lung cancer patients after the progression on a 1st and 2nd generation EGFR tyrosine kinase inhibitors

Targeted therapy has opened a new era in treatment of patients with non-small-cell lung cancer associated with mutations of the epidermal growth factor receptor (EGFR) gene. However, most patients after starting targeted therapy develop progression within 10-12 months. The basic mechanisms of acquired resistance are known, the secondary mutation in exon 20 of EGFR gene is the leading cause in more than a half of the cases. To detect this mutation is important to repeat molecular testing, that, consequently, requiring re-biopsy. Liquid biopsy is considered as an alternative to re-biopsy. Osimertinib is a third generation EGFR-tyrosine kinase inhibitor, possessing antitumor activity, both, in respect of T790M-positive tumors and of tumors with mutations in exons 18, 19 and 21. In the randomized AURA3 trial, the use of osimertinib was effective in 71% of patients, the median progression free survival was 11 months after the progression on1st-line targeted therapy and was statistically significant than in case of chemotherapy application. Patients with brain metastases also show response to osimertinib treatment. In our study, 29 patients received osimertinib after the progression on targeted therapy of the 1st and 2nd generation tyrosine kinase inhibitors. Objective response was reported in 44.8% (complete response - 3.4%), stabilization - 51.7% and progression - 3.5%. We will show the results concerning the time without progression in the near future. The tolerance of treatment is good. Osimertinib has been approved for 1st-line targeted therapy treatment of patients with the T790M mutation upon progression in Russian Federation, thus we have new opportunities to improve the results of the treatment in this group of patients.

Assessment of BCR-ABL1 Fusion Transcripts and Their Association with Response to Imatinib Treatment in Chronic Myeloid Leukemia Patients

Abstract Objectives: BCR-ABL1 fusion transcripts with contrasting data on response to imatinib therapy have been reported from different parts of the world. Hence, the present study aimed to determine the frequencies of transcripts and their association with response to imatinib therapy in chronic myeloid leukemia (CML) patients. Methods: A total of 170 (76 follow-up and 94 imatinib-resistant) CML samples were included in the study. BCR-ABL1 fusion transcripts and expression status were analyzed in all cases using multiplex reverse transcriptase PCyR and real-time PCyR. Sanger sequencing was used for tyrosine kinase domain (TKD) mutation screening in imatinib mesylate-resistant patients. Results: Of 170 CML patients, 36.36% showed b2a2, 63.53% had b3a2, and 2.94% had b2a2 + b3a2 isoforms. Mean platelet counts and blasts were significantly lower in b2a2 carriers (P = 0.0092; P ≤ 0.0001). Patients with b2a2 transcript were found to be more in responders group (both hematological and cytogenetic), whereas b3a2 patients were more in partial responders group and death (P = 0.763; P = 0.309). In follow-up patients, mean baseline BCR-ABL1 expression levels are significantly higher in b2a2 versus b3a2 carriers (P = 0.0351). Of 94 imatinib-resistant patients, 36 (38.29%) had acquired TKD mutations. Among 36 patients, mean BCR-ABL1 levels are significantly higher in b2a2 and b2a2 + b3a2 group (P = 0.0002; P ≤ 0.0001). TKD mutation frequency was more in b3a2 (61.11%) compared to other types. With respect to follow-up status in 36 patients, 17 patients died while 19 were on imatinib higher doses or 2nd-generation tyrosine kinase inhibitors. Of 17 patients, 41.66% had b2a2 transcript and 54.54% had b3a2 transcript. Conclusion: Patients with b3a2 transcripts might be associated with poor response and worse prognosis in CML with imatinib treatment.

Baseline Cytogenetic Response Is a Predictor of Outcome of Third Line 2nd Generation TKI Treatment in Chronic Phase Chronic Myeloid Leukemia Patients

Abstract Introduction. 20-25% of patients (pts) with chronic myeloid leukemia (CML) in chronic phase (CP) failure second line therapy with 2nd generation tyrosine kinase inhibitors (TKI). Many of them are non eligible for allogeneic stem cell transplantation(alloSCT) and are candidates for 3rd line TKIs (TKI3). Thus,it is important to evaluate predictors of 3rd line TKI efficacy. Methods: Prognostic factors for TKI3 were evaluated in 43 pts (male -17; 39,5%) with CML in CP. Median age was 51 (range 23-88)years. All pts obtained Imatinib as first line treatment for a median 17 (range 1-85)months. Second line TKI were Nilotinib in 25 (58%), Dasatinib in 14 (33%) and Bosutinib in 4 (9%) of pts. Median duration of second TKI therapy was 13 (range 1-96) months. The main reason for treatment discontinuation was resistance for both first (35;81%) and second (38; 88%) TKIs.Mutations were revealed before second or third line TKI in 6/21(29%) and 12/28 (43%) pts, respectively, including 3pts with T315I mutation. Additional chromosomal abnormalities (ACAs) were observed in 9/36 pts. At baseline before TKI3 the best cytogenetic response was complete (CCyR), partial (PCyR), minimal or minor (mCyR), no CyR in 7(16%) 6(14%), 8(19%) pts and 22(51%), respectively. Complete hematologic response (CHR) without any CyR was observed in 13/22 (30%) pts. Results: Nilotinib, Dasatinib or Bosutinib were used as TKI3 in 16(37%), 22(51%) and 5(12%) cases, respectively. Median time from diagnosis to TKI3 was 56 (range 13-314) months. Median observation time from TKI3 to data of analysis is 22 (range 8-119) months. Overall CCyR was obtained 8/36 pts (22%) pts without CCyR at baseline. CCyR was reached in 7/14(50%) and only 1/22 (4,5%) pts with any level CyR and no CyR, respectively (p=0,003). CHR obtained 7/9 (78%), but 3/7 (43%) subsequently lost the response within a median of 6 months follow-up. The cumulative rate of CCyR and major molecular response (MMR) on TKI3 according to baseline data are presented in table1. Nearly all patients (5/6; 83%) with PCyR before TKI3 responded. Progression to accelerated (AP) or blastic (BP) phase was observed in 10/22(45%) and 0/21 pts with no CyR or any level CyR at baseline(p=0,0003). Other unfavorable factorsfor disease progression were mutations. AP/BP were observed in 7/12 (58%) and 2/16 (12,5%)(p=0,015)with and without mutations, respectively. Any ACAs 4/9(44%) and 6/27(22%)(p=0,19) More than half of patients 25/43(58%) discontinued TKI3 - median treatment time was 16 (range 2-55)months. Reasons for treatment withdrawal were resistance (16; 64%), toxicity (4;16%), alloSCT (5;20%). Conclusions: According to our study pts with any cytogenetic response, especially with PCyR, and without mutations at baseline benefit 2nd generation TKIs as third line treatment. Thus, in case of alloSCT noneligibility, this cohort of pts are good candidates for 2nd generation TKI as 3rd line treatment. Download : Download high-res image (124KB) Download : Download full-size image Disclosures Shuvaev: Fusion Pharma LLC: Consultancy. Zaritskey: Novartis: Consultancy, Speakers Bureau; Janssen: Consultancy.

Response to Front-Line Imatinib Treatment in Children and Adolescents with CML - Data from a Large Pediatric Cohort

PurposeResults of the prospective trial “CML-PAED-II” assessing treatment efficacy and side effects in children and adolescents with newly diagnosed chronic myeloid leukemia (CML) are reported.Patients and Methods156 patients (age range 1.3-18.0 years, 91 male) with newly diagnosed CML (N= 146 chronic phase (CML-CP), N= 3 accelerated phase (CML-AP), N= 7 blastic phase (CML-BP)) received imatinib upfront (300 mg/m², 400 mg/m², 500 mg/m², respectively). Therapy response, progression-free survival, causes of treatment failure and proportion of patients undergoing stem cell transplantation were analyzed in 148 patients with complete data.ResultsEvent-free survival rate at 18 months for pediatric patients diagnosed in CML-CP (median follow-up time 25 months, range: 0.1-120) was 97% (95% CI, 94.2%-99.9%). According to the 2006 ELN-criteria complete hematologic response at month 3, complete cytogenetic response (CCyR) at month 12, and molecular response (MR3.0) at month 18 were achieved in 98%, in 63%, and 59% of the patients, respectively. At month 36 on continuous first line imatinib or 2nd generation tyrosine kinase inhibitor treatment, 86% of the patients achieved CCyR and 74% achieved MR3.0.66% of the patients experienced at least one side effect. Imatinib-related anemia was the most frequent toxicity observed if all grades were considered (N=98; 66%) while neutropenia was the most frequently reported grade 3/4 hematologic adverse effect (N=22; 15%). Among non-hematologic toxicities, all grades of gastrointestinal toxicity were observed most frequently (N=57, 38%), however, it occurred at lower grades 1/2 in all but one patient. Higher grade 3/4 musculoskeletal pain was also frequent (N=53, 36%). Twenty-seven patients (18%) had to discontinue treatment temporarily while nine patients permanently terminated imatinib due to non-tolerable side effects (neutropenia N= 4, muscle cramps N= 3, skin N= 1, liver N= 1).Thirty-eight patients (27%) experienced imatinib failure because of unsatisfactory response (N= 27) or intolerance (N= 9). 28/148 patients (19%) underwent stem cell transplantation (SCT). In the SCT sub-cohort 2/23 patients diagnosed in CML-CP, 0/1 in CML-AP, and 2/4 in CML-BP, respectively, died of relapse (N=3) or SCT-related complications (N=2).ConclusionThis large pediatric trial provides evidence confirming that first line imatinib in children is highly effective. Observed adverse effects are acceptable and mainly comprise hematological side effects. Long term outcome and effects of a potentially life-long TKI treatment have to be registered in cooperation with adult hematologists in extended surveillance follow-up studies. DisclosuresSuttorp:Novartis: Research Funding. Schrappe:JAZZ Pharma: Consultancy, Research Funding; Baxalta: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; SigmaTau: Consultancy, Research Funding; Medac: Consultancy, Research Funding. Thiede:Novartis: Consultancy, Speakers Bureau; Bayer: Consultancy, Speakers Bureau; Roche: Consultancy; Agendix: Employment.

Upfront treatment with the first and second-generation tyrosine kinase inhibitors in Ph-positive acute lymphoblastic leukemia.

The treatment of Ph-positive acute lymphoblastic leukemia (Ph+ ALL) has entranced tyrosine kinase inhibitors (TKIs) era. Currently both imatinib and dasatinib are registered as the front-line treatment for Ph+ ALL, and the other 2nd-generation TKIs are suggested as an alternative for those who failed the first-line treatment. However, it remains unclear who could benefit from the 2nd-generation TKIs as the first-line treatment for Ph+ ALL. In this study we compared the efficacy and safety of the 1st and 2nd-generation TKIs in the front-line treatment of Ph+ ALL and found a trend toward better disease-free survival (DFS) in the 2nd-generation TKIs group, though no significant difference in early response and long-term survival between the two groups. Furthermore, subgroup analysis showed that if allogeneic hematopoietic stem cell transplantation (allo-HSCT) was incorporated as consolidation, the 2nd-generation TKIs benefited patients with better DFS and overall survival (OS). The two generation TKIs were well tolerated. Higher incidence of acquiring T315I mutation was observed in the patients relapsed on the 2nd-generation TKIs. These findings suggested front-line treatment of Ph+ ALL with the 2nd-generation TKIs might benefit patients with better survival when allo-HSCT was incorporated as consolidation therapy; meanwhile, the higher incidence of T315I mutation in patients relapsed on the 2nd-generation TKIs deserved further attention.

Abstract 1715: EGFR mutational detection in ctDNA, Vortex-enriched CTCs and comparison to tumor tissue in non-small-cell-lung-cancer (NSCLC) patients

Abstract Background: Lung cancer is the leading cause of cancer-related mortality worldwide. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapies, based on the evaluation of EGFR mutation, have shown dramatic clinical benefits. EGFR mutation assays are mainly performed on tumor biopsies, which carry risks and expense and are not always successful. In order to identify the development of secondary EGFR mutations, which cause resistance to 1st and 2nd generation TKI’s and an indication for therapy with a 3rd generation drug, effective and non-invasive monitoring is needed. Liquid biopsy biomarkers, such as circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA), allow such monitoring over the course of the therapy. Interestingly, ctDNA or CTC analysis alone had less sensitivity vs. combining both, with a genotyping of 70% and 80% for CTCs and ctDNA respectively, but 100% when combined2. Vortex technology is a platform enabling label-free capture of CTCs from blood samples and genomic assays downstream3. The aim of this study is to demonstrate the sensitivity of a combined CTC and ctDNA assay through Vortex using blood samples spiked with molecularly-characterized lung cancer cell lines and then to apply this technique to matched blood and tumor samples from NSCLC patients. Method: Lung cancer cell lines with different EGFR mutations (A549: wild type, H1975: L858R+ and T790M+, HCC827: 19del+) were used to validate our CTC workflow. Blood samples and matched tumor tissues were collected from NSCLC patients. Plasma was extracted first for ctDNA assay. CTCs were isolated from the plasma-depleted-blood using Vortex technology, immunostained (CK, Vimentin, CD45) and enumerated. DNA from CTCs, plasma and matched tumor tissue was analyzed for EGFR mutations 19del, L858R and T790M using the ctEGFR kit from EntroGen. Results: Mutant DNA could be identified at a quantity as low as 0.5 ng (~83 cells), with a sensitivity ranging from 0.1% to 2% for a total DNA varying from 25ng (~4 CTCs among 4000 WBCs) to 1ng (~4 CTCs among 200 WBCs). We demonstrated the ability of Vortex technology to enrich CTCs from metastatic NSCLC patients. Processing of plasma-depleted-blood showed the same capture efficiency when compared to whole blood. This makes possible the detection of EGFR mutations on CTC samples collected by Vortex technology. > 10 NSCLC patients are being enrolled in this study and results will be presented at AACR. Conclusion: The ctEGFR mutation assay performed well on both Vortex-enriched CTCs and ctDNA, enabling a low cost approach to analyze EGFR mutation from a single blood tube. This non-invasive EGFR mutation analysis will be potentially a useful tool for monitoring treatment and medication guidance of NSCLC patients. 1. Calabuig-Fariñas et al. Transl Lung Cancer Res. 2016. 2. Sundaresan TK et al. Clin Cancer Res. 2016. 3. Kidess-Sigal E et al. Oncotarget 2016. Citation Format: Haiyan E. Liu, Meghah Vuppalapaty, Clementine A. Lemaire, Charles Wilkerson, Steve C. Crouse, Jonathan W. Goldman, Elodie Sollier-Christen. EGFR mutational detection in ctDNA, Vortex-enriched CTCs and comparison to tumor tissue in non-small-cell-lung-cancer (NSCLC) patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1715. doi:10.1158/1538-7445.AM2017-1715

Abstract 2061: Non-covalent EGFR T790M targeting TKIs inhibit AZD9291 resistant EGFR C797S mutants

Abstract Approximately 10-15% of non-small-cell lung cancers (NSCLC) have epidermal growth factor receptor (EGFR) mutations resulting in increased sensitivity to 1st generation tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib. For common mutations in EGFR, treatment with 1st generation TKIs results in approximately 70% overall response rate, increased progression free survival, and increased quality of life compared to chemotherapy alone. However, resistance to 1st generation TKIs typically develops within ~12 months, and approximately 55% of patients acquire a secondary mutation in EGFR Exon 20, T790M. To overcome resistance, 2nd and 3rd generation covalently binding TKIs targeting T790M mutations have been developed. Recent studies show that approximately 40% of acquired resistance to 2nd and 3rd generation TKIs can also occur via a third acquired EGFR mutation at the site of covalent binding, C797S. To date, there are no standard approved targeted therapies for treating EGFR C797S mutant NSCLC. Moreover, with proposed increased use of covalent inhibitors in the first line setting, C797S mutations are expected to become more prevalent and new strategies to overcome therapeutic resistance will be required. To this end, we have generated stable Ba/F3 and HCC827 NSCLC cell lines expressing C797S mutant EGF receptors with common mutations in EGFR including, L858R/T790M/C797S, and Ex19del/T790M/C797S. EGFR mutant cell lines expressing C797S were screened against 1st, 2nd, and 3rd generation EGFR TKIs and cell viability was determined using Cell Titer Glo. Triple mutant cell lines containing T790M and C797S mutations were not sensitive to any 1st, 2nd, or 3rd generation inhibitors with IC50 values of >10µM, 7.0µM, and 7.6µM, respectively. However Ba/F3 and HCC827 cell lines transfected with EGFR triple mutants were inhibited by non-covalent inhibitors: CUDC-101, an EGFR, HER2 and HDAC inhibitor, and PKC412, a FLT3 inhibitor. In triple mutant Ba/F3 cells, CUDC-101 and PKC412 had IC50 values of 470nM and 250nM in Ex19del/T790M/C797S EGFR mutants, respectively, and IC50 values of 690nM and 270nM in L858R/T790M/C797S EGFR mutants. In HCC827 cells, PKC412 had IC50 values of 610nM and 520nM in L858R/T790M/C797S and Ex19del/T790M/C797S triple mutants, respectively. In addition, western blot analysis of triple mutant Ba/F3 cells showed decreased phosphorylation of EGFR in presence of 50nM PKC412 and 500nM of CUDC-101. Moreover, PKC412 partially decreased p-EGFR expression at 50nM in HCC827 triple mutant cell lines. In conclusion, unlike other EGFR TKIs, the non-covalent EGFR inhibitors CUDC-101 and PKC412 inhibit both T790M and C797S EGFR mutants at low concentrations. Currently, we are establishing additional osimertinib resistant HCC827, H1975, PC9 and H4006 cell lines for further in vitro and in vivo studies. Citation Format: Jacqulyne P. Robichaux, Monique Nilsson, John V. Heymach. Non-covalent EGFR T790M targeting TKIs inhibit AZD9291 resistant EGFR C797S mutants [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2061. doi:10.1158/1538-7445.AM2017-2061

Patient-reported outcomes in patients with NSCLC who progress on 1st-/2nd-generation EGFR TKIs.

e20590 Background: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are recommended for patients with EGFR mutation-positive advanced non-small cell lung cancer (NSCLC). Limited data are available regarding patient-reported outcomes (PROs) in patients who experience progression on 1st-/2nd-generation TKI treatment, which was the focus of this study. Methods: A retrospective chart review of patients with advanced NSCLC (stage IIIb/IV) from 10 US community oncology practices was conducted. Patients were included if they were diagnosed between 1/1/2008 and 1/1/2015, were treated with erlotinib or afatinib (TKIs) either first line (1L) or second line (2L), and had disease progression (per clinician’s assessment) prior to 10/31/2015. Eligible patients with ≥1 Patient Care Monitor record were included in this subset analysis. Linear mixed models were used to evaluate select PROs. Results: The study included 364 patients: 77.7% white, 17.3% African American; and mean (SD) age 66.3 (11.3) years. Of the 241 patients who received systemic anticancer therapies after progression, 33.2% continued on TKIs ± chemotherapy (66.8% chemotherapy alone). PROs were available for 71 of 364 patients. We found that progression was associated with worsening in acute distress, despair, and difficulty breathing ( P< .001, P< .001, P= .048, respectively). Disease progression was also associated with worsening of vomiting and nausea ( P< .001, P= .023, respectively). Patient-reported rash symptoms improved from the TKI treatment period to the post-progression period ( P= .044), which aligned with the incidence of rash in the patient records (61.0% during TKI, 32.9% after progression). Conclusions: As expected, disease progression was associated with worsening of patient psychological symptoms and difficulty in breathing. Interestingly, as disease progressed and patients transitioned from TKI therapies to chemotherapies, there was worsening of vomiting and nausea and a decrease in patient-reported rash symptoms. These findings underscore the need for therapeutic options that improve patient symptomatology after progression on 1st-/2nd-generation EGFR TKIs.

An Open-Label, Phase I Study of Dasatinib in Combination with Decitabine in Patients (Pts) with Accelerated or Blastic Phase Chronic Myeloid Leukemia (CML)

Background: Current treatment for advanced phase CML remains unsatisfactory. Dasatinib induces major cytogenetic response (MCyR) in 31% and 37% of pts with imatinib-resistant or -intolerant accelerated (AP) and blast phase (BP), respectively (Cortes 2007). Hypermethylation is associated with disease progression in CML. In pts with imatinib-refractory CML-AP and CML-BP, low dose decitabine induced MCyR in 12% and 17% of pts, respectively, with similar rates achieved combining decitabine with imatinib (Issa 2005, Oki 2007). The reported synergy between imatinib and decitabine depends upon residual sensitivity to imatinib (La Rosee 2004). We investigated whether improved responses might be achieved through synergy between dasatinib, a 2nd generation tyrosine kinase inhibitors (TKI) and decitabine.Methods: Pts age 18 years or older with CML-AP, CML-BP, or Philadelphia chromosome (+) acute myeloid leukemia (Ph+AML) were enrolled regardless of previous TKI therapy. Pts were assigned to 2 schedules on a 3+3 dose-escalation design to determine the maximum tolerated dose (MTD; primary objective). The starting schedule was decitabine 10mg/m2 daily for 10 days and dasatinib 100 mg daily (schedule A), and decitabine 20mg/m2 daily for 10 days with dasatinib 100 mg (schedule B). The next dose level (target dose) was decitabine 10mg/m2 daily for 10 days (schedule A) or 20 mg/m2 daily for 10 days (schedule B) with dasatinib 140 mg daily. Secondary objectives are to determine the rate of overall hematologic response (OHR) (2 cycles required to be evaluable for response), response duration (RD), overall survival (OS), and toxicity profile. OHR includes complete hematologic response (CHR), no evidence of leukemia (NEL), and minor hematologic response (MiHR). CHR is defined as normal WBC, no blasts or promyelocytes in peripheral blood (PB), ANC ≥1x109/L, platelets >100 x109/L, PB basophils < 5%, ≤ 5% blasts in bone marrow (BM), and no extra-medullary disease. NEL is the same criteria as CHR except for platelets between ≥ 20 x109/L and <100x109/L or ANC between ≥ 0.5x109/L and < 1x109/L. MiHR is defined as <15% blasts in PB and BM, <30% blasts + promyelocytes in BM and PB, <20% basophils in PB, and no extra-medullary disease. Once MTD or target dose (if MTD not exceeded) determined for both arms subsequent pts are to be randomized to the two schedules.Results: A total of 23 pts were enrolled (4 AP, 16 BP, 3 Ph+AML); 21 were evaluable for response. The remaining 2 pts were not evaluable for response since they did not complete 2 cycles of therapy as defined in the protocol, due to drug toxicity (n=1; cardiac arrest due to myocardial infarction) or insurance issues (n=1). Patient characteristics are shown in Table 1. Sixteen pts received prior TKI therapy with a median of 2 TKI per pt (range, 1-4). Three pts had a kinase domain mutation (V299L, E255K, and 1 pt with both L298V and T315I); one other patient had a 162 bp deletion. No dose-limiting toxicity (DLT) was observed at the starting dose level for either schedule. One DLT (among 6 pts) was observed at the target dose level of each schedule (1A: grade 3 heart failure; 1B: grade 4 cardiac arrest), therefore the target dose was considered the dose to be further explored in phase 2 for each arm. Pts received a median of 2 treatment cycles (range 1-11) and 3 pts are still receiving study therapy. Fourteen (67%) pts achieved OHR (7 CHR, 3NEL, 4 MiHR). A MCyR was achieved by 38% (8/21). Median duration of OHR was 3.5 months (95% CI: 2- 4.9). Median OS was 12 months (95% CI: 2.9- 21.3). A total of 11 pts (48%) died: 10 due to disease progression and 1 pt died in complete molecular response from SCT complications. Three pts have ongoing responses, 2 pts with major molecular response (MMR) and one with NEL, with the combination therapy for 5+, 7+, and 3+ cycles, respectively. Six pts received SCT of which 4 pts remain alive 39, 27, 4, and 0.2 months post-SCT; they had achieved CHR, MCyR, MMR, and CHR, respectively with DAC + dasatinib prior to SCT. Grade 3-4 nonhematological toxicity was reported in 17 (74%) pts, most frequent toxicities being infections (26%), bleeding (17%), and acute renal failure (13%).Conclusion: The combination of decitabine plus dasatinib is well tolerated and active in pts with advanced phase CML. Phase 2 portion of this study is in progress to determine the efficacy of this combination and difference in outcome by treatment schedule. [Display omitted] DisclosuresDaver:Karyopharm: Honoraria, Research Funding; Sunesis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Otsuka: Consultancy, Honoraria; Kiromic: Research Funding; Ariad: Research Funding; BMS: Research Funding. Burger:Pharmacyclics: Research Funding. Jabbour:ARIAD: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Novartis: Research Funding; BMS: Consultancy. Cortes:ARIAD: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Teva: Research Funding.

Similar Efficacy of Dasatinib and Nilotinib As Second-Line Therapy in Patients with Chronic Phase Chronic Myeloid Leukemia Failing Imatinib: A Retrospective, Real-Life Study

Background. Use of 2nd generation tyrosine kinase inhibitors (2G-TKIs) dasatinib (DAS) and nilotinib (NIL) in chronic phase (CP) chronic myeloid leukemia (CML) patients failing imatinib (IM) results in around 50% of sustained cytogenetic response, and around 40% major molecular response (MMR). However, these are historical data and it's unclear if there's a significant difference in efficacy of the two 2G-TKIs, especially in the long-term.Aims and methods. We retrospectively analysed 163 CP-CML patients resistant or intolerant to IM that received either DAS (n=95) or NIL (n=68) as second-line therapy. We compared the characteristics of the two groups at the time of CML diagnosis and at the time of IM failure, including the cause of switch to 2G-TKI, duration of IM therapy, IM dose escalation and Hammersmith score to predict the probability of response to 2G-TKIs. Cytogenetic and molecular responses were evaluated according to the ELN recommendations. Sustained deep molecular response (DMR) was defined as MR4 or better lasting ≥ 2 years, ongoing at the last contact, and with at least a Q-PCR test every 6 months. Time to treatment failure (TTF) was calculated from the start of 2G-TKI to any of the followings: progression to accelerated or blast phase (ABP), death for any cause at any time, treatment discontinuation for primary or secondary resistance or intolerance. Progression free survival (PFS) was calculated from the start of 2G-TKI to ABP or death. Overall survival (OS) was calculated from the start of 2G-TKI to death.Results. DAS and NIL cohorts were comparable for age, sex and risk score (Sokal and EUTOS) at diagnosis. Median duration of IM therapy was similar (DAS 19 months, NIL 14 months), but 27/95 patients (28%) had IM dose escalation before DAS compared to only 9/68 (13%) before NIL (p=0.03). There was a higher rate of switch to DAS than to NIL for secondary resistance (26/95, 27% vs 7/68, 10%; p=0.01) while more patients changed from IM to NIL due to intolerance (31/68, 46%, vs 21/95, 22% for DAS; p=0.002). Rates of primary resistance did not differ (47/95, 49% for DAS vs 28/68, 41% for NIL; p=0.37), as well as other causes of switch (1/95, 1% for DAS vs 2/68, 3% for NIL; p=0.77). Hammersmith score was almost identical in the two groups.Complete cytogenetic response (CCyR) was attained in 53/73 (73%) patients not in CCyR at the time of DAS start, and in 31/48 (65%) patients not in CCyR at the time of NIL start (p=0.46). Mean time to CCyR was similar (7.1 months for DAS and 5.3 months for NIL; p=0.30).MMR was achieved in 55/89 (65%) patients not in MMR at the time of DAS start and in 39/61 (65%) patients not in MMR at the time of NIL start (p=0.82). Again, mean time to MMR was not different in the DAS e NIL cohorts (12.4 vs. 8.5 months; p=0.14).DMR was obtained in 39/88 (44%) patients not in DMR at the time of DAS start and in 30/65 (46%) patients not in DMR at the time of NIL start (p=0.95). Sustained DMR was evaluable in 127 patients: 37 patients (29%) achieved sustained DMR, without difference between DAS (24/82, 29%) and NIL (13/45, 29%; p=1.00).With a median follow-up of 44 months (range 1-124), 5-year TTF was similar for DAS (65%, 95%CI 52-75%) and NIL (61%, 95%CI 43-74%; p=0.40) [Figure 1a]. Thirty-two of 95 patients (34%) stopped DAS due to toxicity (19/32, 59%), resistance (11/32, 31%) or other causes (3/32, 10%); 22/68 patients (32%) interrupted NIL for toxicity (11/22, 50%), resistance (8/22, 36%) or other causes (3/22, 14%). Probability of survival and progression were almost identical, with a 5-year PFS of 84% (95%CI 68-89%) for DAS and 92% (95%CI 79-97%) for NIL (p=0.27) [Figure 1b] and a 5-year OS of 89% (95%CI 78-95%) and 96% (95%CI 85-99%) (p=0.31), respectively.Conclusions. With the limits of a retrospective analysis, our data suggest similar efficacy of DAS and NIL after IM failure in CP-CML, with rates of cytogenetic and molecular responses higher than those previously reported and excellent long-term survival. Around 30% achieved sustained DMR with second-line therapy, thus being potentially candidate for TKI discontinuation. DisclosuresTiribelli:Bristol-Myers Squibb: Consultancy, Speakers Bureau; Novartis: Consultancy, Speakers Bureau; Ariad Pharmaceuticals: Consultancy, Speakers Bureau. Bonifacio:Ariad Pharmaceuticals: Consultancy; Pfizer: Consultancy; Bristol Myers Squibb: Consultancy; Novartis: Research Funding; Amgen: Consultancy. Fanin:Novartis: Speakers Bureau.

Cardiovascular Events Among Patients with Chronic Myeloid Leukemia (CML) Treated with Tyrosine Kinase Inhibitors (TKIs)

▪BackgroundTKIs are the mainstay of treatment for CML. Cardiovascular events may occur during the course of therapy with TKI. We present a single institution experience of cardiovascular events among CML patients receiving initial therapy with various TKIs.MethodsWe retrospectively assessed 584 CML patients enrolled on consecutive or parallel prospective frontline TKI clinical trials (imatinib, n=281; dasatinib, n=120; nilotinib, n=132, ponatinib n=51). Treatment-emergent adverse events (TEAE) under the MedRA heading "Cardiovascular" were analyzed. Over 1,080 unique terms are included under this MedRA heading. Poisson regression models assessed factors associated with occurrence of cardiovascular and arterio-thrombotic events.ResultsThe median age (range) at start of treatment was 49 yrs (15 - 87); 41% were female and 79% were white. The overall median time of follow-up was 66 mos, with the longest follow-up for the imatinib (117 mos) cohort and the shortest for the ponatinib (13 mos) cohort. Co-morbid predisposing conditions were present at baseline in the majority of patients, with significant imbalance among treatment arms. Cardiovascular events occurred in 53% of all patients. Hypertension (new or worsening, 42%) was the most prevalent cardiovascular TEAE, followed by rhythm/rate disorders (11%). Arterio-thrombotic event occurred in 7% of all patients (coronary artery disease in 4%, cerebrovascular in 2%, peripheral arterial in 2%). Overall, the incidence rate (IR) of cardiovascular and arterio-thrombotic TEAEs were 13.9 and 1.1 per 100-person years respectively. Ponatinib showed the highest IR of TEAEs (85.5 and 5.1 per 100-person years respectively).In a multivariate analysis, the incidence risk ratio (IRR) of cardiovascular and arterio-thrombotic events were higher for all 2nd-3rd generation TKIs compared to imatinib. The IRR with ponatinib for cardiovascular events was 7.1 (95% CI: 4.7-10.7; p≤0.001) and for arterio-thrombotic events 6.6 (95% CI: 1.8-23.8 p=0.004); dasatinib and nilotinib showed similar IRR among them, both higher than imatinib. In addition, older age was associated with higher IRR of cardiovascular (IRR=1.01, 95% CI: 1.0-1.02; p=0.003) and arterio-thrombotic (IRR=1.04, 95% CI: 1.00-1.07; p=0.023) events adjusted for other variables.ConclusionCardiovascular TEAE are common during the course of therapy with TKI for patients with CML, predominantly for older patients and those on 2nd and 3rd generation TKI (particularly ponatinib). These patients require close monitoring during treatment. Investigation on the mechanism for cardiovascular TEAE with TKIs is required. [Display omitted] [Display omitted] DisclosuresJabbour:BMS: Consultancy; Pfizer: Research Funding; ARIAD: Research Funding; ARIAD: Consultancy; Pfizer: Consultancy; Novartis: Research Funding. Wierda:Novartis: Research Funding; Abbvie: Research Funding; Acerta: Research Funding; Gilead: Research Funding; Genentech: Research Funding. Daver:Otsuka: Consultancy, Honoraria; Sunesis: Consultancy, Research Funding; Ariad: Research Funding; Kiromic: Research Funding; Pfizer: Consultancy, Research Funding; Karyopharm: Honoraria, Research Funding; BMS: Research Funding. Kadia:BMS: Research Funding; Novartis: Honoraria. Burger:Portola: Consultancy; Gilead: Research Funding; Roche: Other: Travel, Accommodations, Expenses; Janssen: Consultancy, Other: Travel, Accommodations, Expenses; Pharmacyclics, LLC, an AbbVie Company: Research Funding. DiNardo:Daiichi Sankyo: Other: advisory board, Research Funding; Novartis: Other: advisory board, Research Funding; Agios: Other: advisory board, Research Funding; Abbvie: Research Funding; Celgene: Research Funding. Ravandi:Seattle Genetics: Consultancy, Honoraria, Research Funding; BMS: Research Funding. Cortes:ARIAD: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Teva: Research Funding.

Correlation of Expression of CD25 in Hematopoietic Stem/Progenitor Cell Fraction of Bone Marrow Cells with Response to Tyrosine Kinase Inhibitors in Chronic Myelogenous Leukemia Patients

Introduction: Tyrosine kinase inhibitors (TKIs) have dramatically improved the prognosis of chronic myelogenous leukemia (CML). The treatment with TKIs continues to improve the depth of response and overall survival of CML patients, but the life-long use of TKI is known to be associated with late complications such as cardiovascular events as well as heavy financial burden, and thus impairs the quality of life. To overcome these issues, many studies evaluating the possibility of TKI discontinuation have been ongoing worldwide. In order to achieve durable treatment-free remission, it is crucial to understand the dynamics of CML-leukemia initiating cells (LICs). We previously reported that CD25 was highly expressed in murine and human CML-LICs (Kobayashi CI et al., Blood, 2014). The aim of this study was to assess whether the proportion of CD25 positive cells in hematopoietic stem/progenitor cell fraction of bone marrow cells in CML patients treated with TKIs is associated with their molecular response and could serve as a novel surrogate marker to stop TKI therapy.Methods: Bone marrow samples were obtained from patients with CML in chronic phase who were diagnosed and have been treated solely with TKIs at Keio University Hospital (Tokyo, Japan). This study was approved by the institutional ethical committee and informed consent was obtained from each patient. Both quantitative and qualitative PCR of BCR-ABL was performed using bone marrow mononuclear cells (BMMNCs). The proportion of CD25 positive cells in bone marrow hematopoietic stem/progenitor cell (HSPC; CD34+CD38-) fraction was evaluated by flow cytometry using FITC-labeled anti-CD34, PE- labeled anti-CD38 and APC-labeled anti-CD25 antibodies. The response to TKIs at the time of evaluation was determined according to the previous report (Yoshida C et al., Int J Clin Oncol, 2012): complete cytogenetic remission (CCyR) defined as Philadelphia chromosome undetectable and quantitative PCR copy numbers >731 among BMMNCs; major molecular remission (MMR) as quantitative PCR copy numbers ≤731, and complete molecular remission (CMR) as undetectable BCR-ABL by quantitative and qualitative PCR.Results: Bone marrow samples obtained from 95 patients were evaluated (median age 53 years old; male/female, 67/28). Analysis was performed prior to TKI exposure in nine patients and under TKI therapy including 2nd generation TKI in 64 patients (imatinib, 22; dasatinib, 33; nilotinib, 9). Remaining 22 patients were treatment free because they enrolled in a clinical trial of TKI discontinuation. The proportion of CD25 positive cells in HSPC fraction significantly decreased in patients with prior TKI exposure relative to patients at diagnosis (n=86; Mean 4.2%, SD 7.0% vs n=9; Mean 22.4%, SD 11.3%, P<0.01). In addition, the proportion of CD25 positive cells in HSPC fraction significantly correlated the level of quantitative PCR (Figure, P<0.0001), and MMR was also dividable from CMR by the proportion of CD25 positive cells (MMR; n=29, Mean 4.6%, SD 4.8% vs CMR; n=49, Mean 2.6%, SD 2.5%, P<0.05). The expression of CD25 was still detected in the majority of patients who achieved CMR, including those who sustained CMR after the discontinuation of TKIs.Conclusion: We confirmed that the expression of CD25 in HSPC fraction of CML patients was significantly correlated with the response to TKI therapy, and may serve as an asset to select patients who are likely to achieve durable treatment-free survival. [Display omitted] DisclosuresKarigane:Celgene: Honoraria. Sakurai:Celgene: Honoraria. Matsuki:Bristol-Myers Squibb: Honoraria; Celgene: Honoraria; Nippon Shinyaku: Honoraria. Kikuchi:Celgene: Honoraria; Takeda Pharmaceutical Company: Honoraria; Kyowa Hakko Kirin: Honoraria. Mitsuhashi:LSI Medience: Consultancy. Okamoto:Sumitomo Dainippon Pharma Co., Ltd.: Research Funding; Asahi Kasei Pharma Corp.: Research Funding; Astellas Pharma Inc.: Research Funding; Shionogi & Co., Ltd.: Research Funding; Nippon Shinyaku Co., Ltd.: Research Funding; Alexion Pharmaceuticals, Inc.: Research Funding; Toyama Chemical Co., Ltd.: Research Funding; Otsuka Pharmaceutical Co., Ltd.: Honoraria, Research Funding; Teijin Pharma Limited: Research Funding; Bristol-Myers Squibb K.K.: Honoraria, Research Funding; Kyowa Hakko Kirin Co., Ltd.: Research Funding; Eisai Co., Ltd.: Research Funding; Chugai Pharmaceutical Co., Ltd.: Research Funding; Pfizer Inc.: Honoraria, Research Funding; JCR Pharmaceuticals Co., Ltd.: Research Funding.

A Population-Based Study of Chronic Myeloid Leukemia Treated with Imatinib in First Line

Background. Chronic myeloid leukemia (CML) treatment is based on company-sponsored and academic trials testing different tyrosine kinase inhibitors (TKIs) as first-line therapies. However these clinical trials included patients selected according to different inclusion and exclusion criteria, particularly age and comorbidities, and with specific treatment obligations. In daily clinical practice (real life), no inclusion and exclusion criteria do exist, and treatment outcomes depend not only on choice of the first-line TKI, but also on doctor- and patient-choice of second- and third-line TKIs. Aims. To investigate the response and the outcome on first-line imatinib, with switch to 2nd generation TKIs in case of failure or toxicity, in BCR-ABL1+ CML patients enrolled in a population-based registry (real-life setting). Methods. We report here the results from a prospective study, enrolling all newly diagnosed patients (N = 236, median age 60 years) living in two Italian regions, that were registered according to population-based criteria and treated front-line with imatinib. The decision to switch to second-line treatment was up to the Local Investigator (no predefined criteria) Definitions: major molecular response (MMR or MR3.0): BCR-ABL1IS ratio 10,000 ABL1 copies; failure and suboptimal response: according to 2009 European LeukemiaNet (ELN) criteria; progression: transformation to advanced phases according to ELN criteria; leukemia-related death (LRD): death after progression. Results. Median age was 60 years at diagnosis and 64 years at last contact, with a median follow up of 48 months (range 2-86 months). High risk patients according to Sokal score and new EUTOS long-term survival (ELTS) score were 23% and 18%, respectively. A switch from imatinib to a second generation TKI was reported in 14% of patients for side-effects, and in 24% for failure or suboptimal response, with an improvement of molecular response in 57% of them. The median time to switch was 8 months for toxicity and 20 months for failure. At 12 months, 55% of all evaluable patients were in MR3.0 or better. At last contact, 75% of all evaluable patients were in MR3.0 or better and 48% were in MR4.0 or better. The molecular response of patients switching for failure or suboptimal response was evaluable in 61/63 patients: improved in 57%, not modified in 38%, worsened by at least 1 log in 5% of patients. Overall, the treatment switch was associated with a remarkable increase of MR3.0 rate: from 10% at the time of switching to 52% at last qPCR. Overall, 33% achieved a stable MR4.0, of whom 22% with imatinib alone, and 11% after switching to a second generation TKI (Table 1). The 5-year overall survival (OS) and leukemia-related survival (LRS) were 85% and 93%, respectively. Twenty-seven patients (11%) died, of whom 13 (6%) of leukemia, after disease progression and 14 (6%) of "other" causes, without any evidence of progression. Cardiovascular complications were reported in 4% of patients treated with imatinib alone and in 6% of patients who received nilotinib in second-line. OS was not affected by age in the interval between 18 and 69 years (5-year OS 92%, ranging from 89% to 95 % in the different decades), but 5-year OS probabilities of elderly (70-79 years) and very elderly patients (≥ 80 years) were significantly lower (78%, P = 0.003, and 34%, P Conclusions. The results of this prospective population-based study emphasize the importance of second-line treatment in the clinical practice: the CML management with the 3 available TKIs in the period 2008-2012, according to current treatment recommendations for switching and without any predefined obligation, resulted in response rates and outcomes, that are in the high range of prospective interventional studies investigating the efficacy and the safety of a single TKI in selected patients. This study provides a robust dataset on the results of CML treatment with TKI in clinical practice, that will be important for interpreting and evaluating the results of the next prospective studies, arguably limited to selected patients. Disclosures Castagnetti:Bristol-Myers Squibb: Consultancy, Honoraria; ARIAD Pharmaceuticals: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Gugliotta:Bristol Myers Squibb: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Marasca:Janssen: Consultancy, Honoraria, Membership on an entity9s Board of Directors or advisory committees, Research Funding; Gilead: Consultancy, Honoraria, Membership on an entity9s Board of Directors or advisory committees; Pfizer: Honoraria; Roche: Honoraria. Soverini:Novartis: Consultancy; Bristol-Myers Squibb: Consultancy; Ariad: Consultancy. Martinelli:Genentech: Consultancy; ARIAD: Consultancy; Roche: Consultancy; Bristol-Myers Squibb: Speakers Bureau; Novartis: Speakers Bureau; MSD: Consultancy; Pfizer: Consultancy, Speakers Bureau; Amgen: Consultancy. Cavo:Bristol-Myers Squibb: Honoraria; Amgen: Honoraria; Takeda: Honoraria; Celgene: Honoraria, Research Funding; Janssen: Honoraria, Research Funding. Rosti:Novartis: Honoraria, Research Funding, Speakers Bureau; Pfizer: Honoraria, Research Funding, Speakers Bureau; Roche: Honoraria, Research Funding, Speakers Bureau; Incyte: Honoraria, Research Funding, Speakers Bureau; BMS: Honoraria, Research Funding, Speakers Bureau. Baccarani:Ariad: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Pfizer: Consultancy, Honoraria, Speakers Bureau.

CML Patients Outcome after TKI Discontinuation: A Single Institution Experience in the US

Chronic myeloid leukemia (CML) patients who achieve a complete cytogenetic response (CCyR) with tyrosine kinase inhibitor (TKI) have an expected survival rate comparable to that of the general population. It is practice to continue TKI therapy indefinitely. However, this chronic therapy may impact patient9s lives either by its associated adverse events, or its influence on real-life events (eg. pregnancy, financial burden). Therefore, treatment discontinuation has been increasingly sought. Discontinuation of therapy for patients with sustained MR4.5 has been associated with 30-50% sustained molecular response in previous studies. However, patients may sometimes choose to discontinue therapy for various reasons regardless of the response. We retrospectively analyzed the outcome of 95 patients with CML who discontinued TKI therapy at a single institution. Median age at diagnosis was 50 years (range 26 - 75), 56 (59%) were females. Median follow up from diagnosis to treatment discontinuation was 120 months. TKI was the initial therapy in 62 patients (41 imatinib, 7 nilotinib, 12 dasatinib, 1 bosutinib, 1 ponatinib) and interferon in 33 patients (34%). At time of discontinuation, 67 patients (71%) were receiving their first TKI (48 imatinib, 6 nilotinib, 12 dasatinib, 1 ponatinib) while 25 (26%) and 3 (3%) patients were receiving their second and third TKI respectively. All patients achieved complete cytogenetic response (CCyR) and major molecular response (MMR) in a median of 3 (range 2-93) and 9 months (range 2-132) respectively. MR4.5 was achieved in 92 (97%) patients at a median of 17 months. Three patients had MMR as their best response. Patients received TKI for a median of 104 months (range 8-203) before discontinuation. Fifty two patients (54%) discontinued therapy due to adverse events, 27 (28%) electively due to sustained MR4.5, 7 (7%) due to pregnancy, 6 (6%) for financial reasons and 3 (3%) due to the occurrence of a second cancer. At time of discontinuation all patients were in CCyR; 90 patients (95%) were in MR4.5 and 5 patients (5%) in MMR. The median MR4.5 duration before discontinuation was 75 months (range 1-178); 84 had a sustained MR4.5 for at least 2 years and 59 for at least 5 years. After a median follow-up from treatment discontinuation of 23 months (0 to 113 months), 38 (40%) patients have lost their response at a median of 4 months (range 1-34) after discontinuation; 10 patients lost response after 12 months from discontinuation. Among patients with MR4.5 at discontinuation, molecular relapse occurred in 33 patients (37%) at a median of 4 months (range 1-34; 8 after 12 months from discontinuation). All 5 patients with MMR at discontinuation loss their response at a median of 8 months (range 2-14). Patients receiving imatinib, dasatinib or nilotinib had a median TKI treatment duration of 117, 64 and 65 months before discontinuation, and lost their response at a rate of 33%, 56% and 46%, respectively. Relapse rate for patients with MR4.5 sustained >2 years was 32%, whereas those with This analysis shows that patients with less than MR4.5 at time of discontinuation have higher risk of relapse. The lower percentage of relapse seen in patients who had been on imatinib likely represents the longer period of treatment before discontinuation compared to the 2nd generation TKIs. Late relapses (e.g., beyond a year) occur in a subset of patients. Although the majority of patients who lose their response after discontinuation respond to retreatment, treatment discontinuation is still not recommended outside clinical trials. Disclosures Jain:Pfizer: Consultancy, Honoraria, Research Funding; Celgene: Research Funding; Genentech: Research Funding; Servier: Consultancy, Honoraria; Seattle Genetics: Research Funding; Abbvie: Research Funding; Infinity: Research Funding; ADC Therapeutics: Consultancy, Honoraria, Research Funding; Novimmune: Consultancy, Honoraria; Pharmacyclics: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria; Incyte: Research Funding; BMS: Research Funding. Daver:BMS: Research Funding; Karyopharm: Honoraria, Research Funding; Pfizer: Consultancy, Research Funding; Ariad: Research Funding; Kiromic: Research Funding; Sunesis: Consultancy, Research Funding; Otsuka: Consultancy, Honoraria. Konopleva:Calithera: Research Funding; Cellectis: Research Funding. DiNardo:Abbvie: Research Funding; Daiichi Sankyo: Other: advisory board, Research Funding; Novartis: Other: advisory board, Research Funding; Celgene: Research Funding; Agios: Other: advisory board, Research Funding. Jabbour:ARIAD: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Novartis: Research Funding; BMS: Consultancy. Cortes:ARIAD: Consultancy, Research Funding; Bristol-Myers Squib: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Teva: Research Funding.

A Meta-Analysis and Meta-Regression of the Efficacy of Front-Line Treatment Combinations with Ponatinib Versus 1st- and 2nd-Generation Tyrosine Kinase Inhibitors for Ph+ Acute Lymphoblastic Leukemia

▪Background: The current standard induction therapy for de novo Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) is a tyrosine kinase inhibitor (TKI) in combination with chemotherapy or corticosteroids. Three generations of TKIs are currently available for the treatment of Ph+ ALL. Ponatinib, a third generation multi-targeted TKI, is a more potent inhibitor of BCR/ABL than previous generations. It also is effective in cases where there is a threonine-to-isoleucine substitution at position 315 (T315I mutation), which confers resistance to all first- and second-generation TKIs (i.e., imatinib, dasatinib, and nilotinib). However, evidence on the comparative effectiveness of front-line combination therapy with ponatinib relative to other TKIs in de novo Ph+ ALL has not been well-established.Aims: The purpose of this study is to evaluate the effectiveness, as measured by complete molecular response (CMR) and 2- and 3-year overall survival (OS), of front-line treatment combinations with ponatinib versus first- and second-generation TKIs in de novo Ph+ ALL.Methods: Twenty-six studies of front-line Ph+ ALL treatment with TKI in combination with chemotherapy or corticosteroids (18 studies of imatinib, 5 of dasatinib, 2 of nilotinib, and 1 of ponatinib) were identified from published targeted literature reviews and recently published trials. These consisted of 25 phase 2 through 4 trials and 1 retrospective analysis. Study arms in which patients received chemotherapy or corticosteroids only, a single TKI agent, or in which they received autologous stem cell transplant exclusively were excluded. Data on aggregated patient characteristics were extracted and summarized using the median (range). The proportions of patients achieving CMR (following induction or consolidation therapy) and 2- and 3-year OS were also extracted from all study arms and summarized by TKI group (ponatinib versus all other first and second generation TKIs) using pooled estimates with 95% confidence intervals (CIs) from a random-effects meta-analysis. A binomial distribution was assumed to calculate the 95% CIs for the ponatinib trial. Multivariate logistic meta-regressions were conducted to examine the association between each TKI treatment group and CMR rates, 2-year OS, and 3-year OS, separately, adjusting for age and gender.Results: A total of 32 TKI treatment arms were included in the analysis. The median (range) of age across trial arms was 46 years (36-69 years) and proportion of male patients was 53% (42-67%). The pooled proportion of patients achieving CMR with ponatinib was higher than that with first and second generation TKIs (79% versus 34%). The pooled 2- and 3-year OS with ponatinib were also higher than those with other TKIs (2-year: 83% versus 58%; 3-year: 79% versus 50%). Relative to other TKIs, ponatinib was associated with a statistically significant 6.09-fold increase in the odds of achieving CMR (N=25) [odds ratio=6.09 (95% CI: 1.16-31.90), p=0.034]. While ponatinib was not significantly associated with an increase in the odds of 2-year OS (N=27) [odds ratio=3.70 (95% CI: 0.93-14.73), p=0.062], it was associated with a statistically significant 4.49-fold increase in the odds of 3-year OS (N=19) [odds ratio=4.49 (95% CI: 1.00-20.13), p=0.050] compared to earlier generation TKIs.Conclusion: Frontline treatment with ponatinib in combination with chemotherapy or corticosteroids was associated with significantly better odds of CMR and 3-year OS in patients newly diagnosed with Ph+ ALL than combination therapy with earlier generations of TKIs. In particular, ponatinib was associated with a 6-fold increase in CMR, the most important factor in predicting long-term survival outcomes. The improved efficacy of ponatinib in Ph+ ALL may be particularly important for patients who are ineligible to undergo stem cell transplantation due to lack of suitably matched donors, advanced age, or significant comorbidities. In such cases, combination therapy with TKI may be a suitable alternative. Though the number of studies included was small and few covariates could be used to adjust for heterogeneity across trials, the results suggest that ponatinib in combination with chemotherapy may represent an effective front-line treatment option for patients with Ph+ ALL. Prospective head-to-head clinical trials are needed to confirm these results.Sponsor: ARIAD Pharmaceuticals, Inc. [Display omitted] DisclosuresJabbour:ARIAD: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Novartis: Research Funding; BMS: Consultancy. DerSarkissian:ARIAD: Research Funding. Duh:Allergan: Consultancy; Abbvie: Consultancy; Novartis: Research Funding; GSK: Research Funding; Bayer: Research Funding; Janssen: Research Funding; Eisai: Research Funding; Pfizer: Research Funding; Medtronic: Research Funding; Takeda: Research Funding; Novo Nordisk: Research Funding; Sanofi: Research Funding; Ariad: Research Funding. McCormick:ARIAD: Research Funding. Cheng:ARIAD: Research Funding. McGarry:ARIAD: Employment, Equity Ownership. Souroutzidis:ARIAD: Research Funding. Huang:ARIAD: Employment, Equity Ownership. Kantarjian:Bristol-Myers Squibb: Research Funding; ARIAD: Research Funding; Amgen: Research Funding; Pfizer Inc: Research Funding; Delta-Fly Pharma: Research Funding; Novartis: Research Funding.

Patient reported outcome of tyrosine kinase inhibitor related side effects and their impact on daily life in Chinese patients with chronic myeloid leukemia in the chronic phase

目的评估中国慢性髓性白血病（CML）慢性期（CP）患者报告的酪氨酸激酶抑制剂（TKI）相关不良反应及其对日常生活的影响。方法2014年5月至11月在全国范围内向正在接受TKI治疗的成年CML患者发放无记名调查问卷。TKI不良反应对患者日常生活的影响程度采用自我报告的形式，以1分（没有影响）至5分（严重影响）进行评估。结果731例CML-CP受访者报告了TKI相关不良反应影响其日常生活评分，中位年龄41 (18~88）岁，男性407例（56%），560例（77%）确诊至TKI治疗时间< 1年。中位TKI治疗时间为3（<1~13）年，549例（75%）获得完全细胞遗传学反应，301例（41%）获得完全分子学反应。TKI最多见的不良反应依次为水肿（44%）、乏力（38%）、胃肠道不适（32%）、面部颜色改变（19%）、肌肉痉挛（19%）、皮疹（14%）、肝功能异常（12%）、体重增加（12%）和血细胞计数降低（8%）。多因素分析显示，TKI服药时间<4年是乏力的独立影响因素；女性、年龄≥40岁、服用一代TKI者容易发生水肿；服用一代TKI容易发生胃肠道不适；服用二代TKI容易出现皮疹及肝功能异常；女性容易出现体重增加；确诊至TKI治疗时间≥1年、服用一代TKI者较易出现肌肉痉挛；服用仿制品是血细胞计数降低的独立影响因素。患者自我报告TKI相关不良反应影响日常生活的评分显示218例（30%）没有影响（1分），375例（51%）受轻中度影响（2~3分），138例（19%）受严重影响（4~5分）。多因素分析显示，仅将人口学特征纳入分析时，女性、年龄≥40岁、服用仿制品、TKI服药时间<4年与受访者较高的日常生活受影响程度显著相关；将不良反应也纳入多因素分析后，未接受高等教育、TKI服药时间<4年、服用仿制品以及以下不良反应：水肿、乏力、胃肠道不适、面部颜色改变、皮疹和肝功能异常与较高的日常生活受影响程度相关。结论服用TKI的中国CML-CP患者中，水肿、乏力、胃肠道不适、皮疹、面部颜色改变和肝功能异常是最常见的、影响其日常生活的药物不良反应。女性、年龄≥40岁、未接受高等教育、服用仿制品和TKI治疗时间较短与患者日常生活受影响显著相关。

Abstract 4663: Combination of c-Met inhibitor tepotinib (MSC2156119J) and a third-generation EGFR inhibitor can overcome double resistance mediated by EGFR T790M mutation and c-Met amplification in non-small cell lung cancer models

Abstract In clinical practice, acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) in EGFR-mutant non-small cell lung cancer (NSCLC) causes EGFR TKI treatment failure. Several resistance mechanisms have been identified; EGFR T790M mutation and aberrant activation of c-Met through c-Met gene amplification and/or HGF upregulation are the two most common mechanisms. We have previously shown that combining the highly selective c-Met inhibitor tepotinib with 1st or 2nd-generation EGFR TKIs overcomes gefitinib resistance caused only by c-MET amplification. Third-generation EGFR TKIs such as rociletinib have been developed specifically to overcome T790M-mediated resistance to EGFR TKIs. We hypothesized that combining a 3rd-generation EGFR TKI with tepotinib could overcome resistance to a 1st or 2nd-generation EGFR TKI (e.g. gefitinib) regardless of the mechanism of resistance. We assessed the efficacy of tepotinib and a Merck-synthesized version of rociletinib (MSR) as monotherapy or in combination in a NSCLC cell line xenograft model (HCC827-GR-T790M) with an EGFR del 19 mutation, c-Met amplification, and exogenous T790M expression, and in a patient-derived xenograft model (DFCI081) with an EGFR del 19 mutation and c-Met amplification, but not a T790M mutation. Single-agent tepotinib, erlotinib, and afatinib did not show antitumor activity in HCC827-GR-T790M xenografts and tumors progressed on treatment (median tumor volume [TV] changes &amp;gt;73%). The combinations of tepotinib + erlotinib and tepotinib + afatinib delayed tumor regrowth more than single-agent therapy, but were no more effective than single-agent MSR. In contrast, the combination of tepotinib + MSR had strong antitumor activity in this model with double resistance due to c-Met amplification and exogenous T790M expression, resulting in complete tumor regression (median TV change -97%). In the patient-derived xenograft model DFCI081, tumors progressed under single-agent therapy with the EGFR TKIs erlotinib, afatinib, and MSR, as expected given that this cell line expresses c-Met. In contrast, tepotinib induced complete tumor regression as monotherapy and when combined with each of the EGFR TKIs (median TV change -100%). Complete regression was maintained until the end of the 60-day observation period after treatment termination. These findings are compatible with the hypothesis that combining tepotinib with a 3rd-generation EGFR TKI to overcome double resistance to 1st and 2nd-generation TKIs mediated by T790M and c-Met in NSCLC is more effective than using either agent alone. Furthermore, whereas EGFR TKIs were not effective in tumor models showing c-Met amplification and EGFR del 19 mutation but not T790M mutation, ie resistance is c-Met mediated, tepotinib monotherapy induced complete tumor regression. Citation Format: Manja Friese-Hamim, Giuseppe Locatelli, Friedhelm Bladt. Combination of c-Met inhibitor tepotinib (MSC2156119J) and a third-generation EGFR inhibitor can overcome double resistance mediated by EGFR T790M mutation and c-Met amplification in non-small cell lung cancer models. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4663.

Recommandations 2015 du France Intergroupe des Leucémies Myéloïdes Chroniques pour la gestion du risque d’événements cardiovasculaires sous nilotinib au cours de la leucémie myéloïde chronique

Tyrosine kinase inhibitors targeting the BCR-ABL oncoprotein represent an outstanding progress in chronic myeloid leukemia and long-term progression-free survival has become a reality for a majority of patients. However, tyrosine kinase inhibitors may at best chronicize rather than cure the disease thus current recommendation is to pursue treatment indefinitely. As a consequence, high quality treatment and care must integrate optimal disease control and treatment tolerability. Tyrosine kinase inhibitors have an overall favorable safety profile in clinical practice since most adverse events are mild to moderate in intensity. However, recent evidence has emerged that new generation tyrosine kinase inhibitors may sometimes damage vital organs and if not adequately managed, morbidity and mortality may increase. The 2nd generation tyrosine kinase inhibitor nilotinib is licensed for the treatment of chronic myeloid leukemia with resistance or intolerance to imatinib and newly diagnosed chronic phase-chronic myeloid leukemia. Nilotinib represents an important therapeutic option but it is associated with an increased risk of cardiovascular events. The purpose of this article by the France Intergroupe des Leucémies Myéloïdes Chroniques is to provide an overview of nilotinib efficacy and cardiovascular safety profile and to propose practical recommendations with the goal to minimize the risk and severity of cardiovascular events in nilotinib-treated patients.