Stephen J. Blakemore

Pevonedistat (MLN4924), a First-in-Class NEDD8-activating enzyme inhibitor, in patients with acute myeloid leukaemia and myelodysplastic syndromes: a phase 1 study

This trial was conducted to determine the dose‐limiting toxicities (DLTs) and maximum tolerated dose (MTD) of the first in class NEDD8‐activating enzyme (NAE) inhibitor, pevonedistat, and to investigate pevonedistat pharmacokinetics and pharmacodynamics in patients with acute myeloid leukaemia (AML) and myelodysplastic syndromes (MDS). Pevonedistat was administered via a 60‐min intravenous infusion on days 1, 3 and 5 (schedule A, n = 27), or days 1, 4, 8 and 11 (schedule B, n = 26) every 21‐days. Dose escalation proceeded using a standard ‘3 + 3’ design. Responses were assessed according to published guidelines. The MTD for schedules A and B were 59 and 83 mg/m2, respectively. On schedule A, hepatotoxicity was dose limiting. Multi‐organ failure (MOF) was dose limiting on schedule B. The overall complete (CR) and partial (PR) response rate in patients treated at or below the MTD was 17% (4/23, 2 CRs, 2 PRs) for schedule A and 10% (2/19, 2 PRs) for schedule B. Pevonedistat plasma concentrations peaked after infusion followed by elimination in a biphasic pattern. Pharmacodynamic studies of biological correlates of NAE inhibition demonstrated target‐specific activity of pevonedistat. In conclusion, administration of the first‐in‐class agent, pevonedistat, was feasible in patients with MDS and AML and modest clinical activity was observed.

Disrupting Protein NEDDylation with MLN4924 Is a Novel Strategy to Target Cisplatin Resistance in Ovarian Cancer

Purpose: Ovarian cancer has the highest mortality rate of all female reproductive malignancies. Drug resistance is a major cause of treatment failure and novel therapeutic strategies are urgently needed. MLN4924 is a NEDDylation inhibitor currently under investigation in multiple phase I studies. We investigated its anticancer activity in cisplatin-sensitive and -resistant ovarian cancer models. Experimental Design: Cellular sensitivity to MLN4924/cisplatin was determined by measuring viability, clonogenic survival, and apoptosis. The effects of drug treatment on global protein expression, DNA damage, and reactive oxygen species generation were determined. RNA interference established natural born killer/bcl-2–interacting killer (NBK/BIK) as a regulator of therapeutic sensitivity. The in vivo effects of MLN4924/cisplatin on tumor burden and key pharmacodynamics were assessed in cisplatin-sensitive and -resistant xenograft models. Results: MLN4924 possessed significant activity against both cisplatin-sensitive and -resistant ovarian cancer cells and provoked the stabilization of key NEDD8 substrates and regulators of cellular redox status. Notably, MLN4924 significantly augmented the activity of cisplatin against cisplatin-resistant cells, suggesting that aberrant NEDDylation may contribute to drug resistance. MLN4924 and cisplatin cooperated to induce DNA damage, oxidative stress, and increased expression of the BH3-only protein NBK/BIK. Targeted NBK/BIK knockdown diminished the proapoptotic effects of the MLN4924/cisplatin combination. Administration of MLN4924 to mice bearing ovarian tumor xenografts significantly increased the efficacy of cisplatin against both cisplatin-sensitive and -resistant tumors. Conclusions: Our collective data provide a rationale for the clinical investigation of NEDD8-activating enzyme (NAE) inhibition as a novel strategy to augment cisplatin efficacy in patients with ovarian cancer and other malignancies. Clin Cancer Res; 19(13); 3577–90. ©2013 AACR.

Tazemetostat, an EZH2 inhibitor, in relapsed or refractory B-cell non-Hodgkin lymphoma and advanced solid tumours: a first-in-human, open-label, phase 1 study

BACKGROUND Activating enhancer of zeste homolog 2 (EZH2) mutations or aberrations of the switch/sucrose non-fermentable (SWI/SNF) complex (eg, mutations or deletions of the subunits INI1 or SMARCA4) can lead to aberrant histone methylation, oncogenic transformation, and a proliferative dependency on EZH2 activity. In this first-in-human study, we aimed to investigate the safety, clinical activity, pharmacokinetics, and pharmacodynamics of tazemetostat, a first-in-class selective inhibitor of EZH2. METHODS We did an open-label, multicentre, dose-escalation, phase 1 study using a 3 + 3 design with planned cohort expansion at the two highest doses below the maximally tolerated dose. The study was done at two centres in France: Institut Gustave Roussy (Villejuif, Val de Marne) and Institut Bergonié (Bordeaux, Gironde). Eligible patients had relapsed or refractory B-cell non-Hodgkin lymphoma or an advanced solid tumour and were older than 18 years, with Eastern Cooperative Oncology Group performance status of 0 or 1, and adequate end-organ function. Tazemetostat was administered orally from 100 mg twice daily to 1600 mg twice daily in 28-day cycles. The primary endpoint was to establish the maximum tolerated dose or recommended phase 2 dose of tazemetostat, as determined by dose-limiting toxicities, laboratory values, and other safety or pharmacokinetic measures in cycle one according to local investigator assessment. Safety was assessed in patients who received at least one dose of tazemetostat; antitumour activity was assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT01897571. The phase 1 part of the study is complete, and phase 2 is ongoing. FINDINGS Between June 13, 2013, and Sept 21, 2016, 64 patients (21 with B-cell non-Hodgkin lymphoma, and 43 with advanced solid tumours) received doses of tazemetostat. The most common treatment-related adverse events, regardless of attribution, were asthenia (21 [33%] of 64 treatment-related events), anaemia (nine [14%]), anorexia (four [6%]), muscle spasms (nine [14%]), nausea (13 [20%]), and vomiting (six [9%]), usually grade 1 or 2 in severity. A single dose-limiting toxicity of grade 4 thrombocytopenia was identified at the highest dose of 1600 mg twice daily. No treatment-related deaths occurred; seven (11%) patients had non-treatment-related deaths (one at 200 mg twice daily, four at 400 mg twice daily, and two at 1600 mg twice daily). The recommended phase 2 dose was determined to be 800 mg twice daily. Durable objective responses, including complete responses, were observed in eight (38%) of 21 patients with B-cell non-Hodgkin lymphoma and two (5%) of 43 patients with solid tumours. INTERPRETATION Tazemetostat showed a favourable safety profile and antitumour activity in patients with refractory B-cell non-Hodgkin lymphoma and advanced solid tumours, including epithelioid sarcoma. Further clinical investigation of tazemetostat monotherapy is ongoing in phase 2 studies in adults and a phase 1 study for children, which are currently enrolling patients who have B-cell non-Hodgkin lymphoma and INI1-negative or SMARCA4-negative tumours. FUNDING Epizyme and Eisai.

The DOT1L inhibitor pinometostat reduces H3K79 methylation and has modest clinical activity in adult acute leukemia

Pinometostat (EPZ-5676) is a first-in-class small-molecule inhibitor of the histone methyltransferase disrupter of telomeric silencing 1-like (DOT1L). In this phase 1 study, pinometostat was evaluated for safety and efficacy in adult patients with advanced acute leukemias, particularly those involving mixed lineage leukemia (MLL) gene rearrangements (MLL-r) resulting from 11q23 translocations. Fifty-one patients were enrolled into 6 dose-escalation cohorts (n = 26) and 2 expansion cohorts (n = 25) at pinometostat doses of 54 and 90 mg/m2 per day by continuous intravenous infusion in 28-day cycles. Because a maximum tolerated dose was not established in the dose-escalation phase, the expansion doses were selected based on safety and clinical response data combined with pharmacodynamic evidence of reduction in H3K79 methylation during dose escalation. Across all dose levels, plasma pinometostat concentrations increased in an approximately dose-proportional fashion, reaching an apparent steady-state by 4-8 hours after infusion, and rapidly decreased following treatment cessation. The most common adverse events, of any cause, were fatigue (39%), nausea (39%), constipation (35%), and febrile neutropenia (35%). Overall, 2 patients, both with t(11;19), experienced complete remission at 54 mg/m2 per day by continuous intravenous infusion, demonstrating proof of concept for delivering clinically meaningful responses through targeting DOT1L using the single agent pinometostat in MLL-r leukemia patients. Administration of pinometostat was generally safe, with the maximum tolerated dose not being reached, although efficacy as a single agent was modest. This study demonstrates the therapeutic potential for targeting DOT1L in MLL-r leukemia and lays the groundwork for future combination approaches in this patient population. This clinical trial is registered at www.clinicaltrials.gov as NCT01684150.

Mechanisms of Pinometostat (EPZ-5676) Treatment–Emergent Resistance in MLL-Rearranged Leukemia

DOT1L is a protein methyltransferase involved in the development and maintenance of MLL-rearranged (MLL-r) leukemia through its ectopic methylation of histones associated with well-characterized leukemic genes. Pinometostat (EPZ-5676), a selective inhibitor of DOT1L, is in clinical development in relapsed/refractory acute leukemia patients harboring rearrangements of the MLL gene. The observation of responses and subsequent relapses in the adult trial treating MLL-r patients motivated preclinical investigations into potential mechanisms of pinometostat treatment-emergent resistance (TER) in cell lines confirmed to have MLL-r. TER was achieved in five MLL-r cell lines, KOPN-8, MOLM-13, MV4-11, NOMO-1, and SEM. Two of the cell lines, KOPN-8 and NOMO-1, were thoroughly characterized to understand the mechanisms involved in pinometostat resistance. Unlike many other targeted therapies, resistance does not appear to be achieved through drug-induced selection of mutations of the target itself. Instead, we identified both drug efflux transporter dependent and independent mechanisms of resistance to pinometostat. In KOPN-8 TER cells, increased expression of the drug efflux transporter ABCB1 (P-glycoprotein, MDR1) was the primary mechanism of drug resistance. In contrast, resistance in NOMO-1 cells occurs through a mechanism other than upregulation of a specific efflux pump. RNA-seq analysis performed on both parental and resistant KOPN-8 and NOMO-1 cell lines supported two unique candidate pathway mechanisms that may explain the pinometostat resistance observed in these cell lines. These results are the first demonstration of TER models of the DOT1L inhibitor pinometostat and may provide useful tools for investigating clinical resistance. Mol Cancer Ther; 16(8); 1669–79. ©2017 AACR.

PRELIMINARY EVIDENCE OF A MOLECULAR PREDICTOR OF TAZEMETOSTAT RESPONSE, BEYOND EZH2 MUTATION, IN NHL PATIENTS VIA CHARACTERIZATION OF ARCHIVE TUMOR AND CIRCULATING TUMOR DNA

Introduction: EZH2, a histone methyl transferase subunit of Polycomb repressor complex 2, is frequently mutated in DLBL. Inhibitors of EZH2 have demonstrated promising responses in early clinical trials. We examined the frequency of EZH2 mutation in 2 large prospective series of DLBL and correlated this to clinical outcomes in relation to other biological features. Methods: Patients (pts) received standard immunochemotherapy regimens as first‐line treatment for DLBL. Sanger sequencing (SS) focusing on “hotspot” mutation sites in exons 16 and 18 was successful in 1052 of 1097 DLBL samples enrolled in the UK NCRI Molecular Profiling for Lymphoma (MaPLe) study. Next generation sequencing (NGS) using Fluidigm Access Array PCR and Illumina MiSeq was used to profile a separate cohort of 365 pts enrolled in the UK NCRI/ SAKK REMoDL‐B trial (NCT01324596) (CRUKE/10/024). In these cases, cell of origin (COO) was determined by gene expression profiling (GEP) using Illumina WG‐DASL. Results: EZH2 mutations were detected in 9% of DLBL pts (98/1052) by SS and 15% (54/365) by NGS. Ninety‐five percent of mutations were at Y646 position in exon 16. EZH2mutations were strongly associated with GCB subtype, occurring in 27% of cases (50/185) versus 0/ 106 in ABC subtype and (4/71) in unclassified subtype (P < .0001). Overall, EZH2 mutations were not significantly associated with age, sex, performance status, stage, or IPI, compared to unmutated GCB DLBL. PFS was similar between EZH2 mutated and unmutated GCB DLBL subtype: 78.5% vs 80.7% at 30 months, HR 1.06 (95% CI, 0.62‐1.81) (P = .844). A subset of GCB cases showed Burkitt‐like GEP, associated with inferior progression free survival (PFS) HR 2.21 (95% CI, 1.28‐7.73) (P = .012), among which 11/24, where mutation status was available, had EZH2 mutations. There was heterogeneity in progression free survival identified by presence or absence of EZH2 mutations and Burkitt‐like gene expression signature. Conclusions: EZH2 mutations are significantly associated with the DLBL GCB‐subtype and more common in cases identified as Burkitt‐ like by GEP. Overall outcomes are similar in mutant and wild‐type cases when adjusted for COO and IPI, but Burkitt‐like cases that carry EZH2 mutations may be a preferential subset in which to test targeted therapies.

Abstract C12: Identification of biomarkers and pathways associated with response to the DOT1L inhibitor Pinometostat (EPZ-5676) in MLL-r leukemia

Pinometostat is a highly selective first in class DOT1L inhibitor currently in Phase 1 clinical trials in adult and pediatric leukemia patients (pts) with MLL rearrangements (MLL-r or MLL-PTD). Preliminary results of the adult trial have demonstrated clinical activity including complete remissions in a subset of patients (Stein, 2014). Investigation and identification of candidate molecular correlates of pinometostat response in both pt samples and cell lines are reported. RNA and DNA were isolated from PBMCs and/or bone marrow collected prior to treatment from 18 pts enrolled in the adult pinometostat Phase 1 study (CT.gov: NCT01684150), at the following doses 24 (n = 2), 36 (n = 3), 54 (n = 6), 80 (n = 3) and 90 mg/m2/day doses (n = 4). mRNA transcript abundance was assessed using whole genome RNASeq and DNA variants were determined using a 194 gene panel, MyAML (Genection Inc.). Correlations of transcript abundance and DNA variants detected with categorical (responder = CR or PR [n = 3], or no response [n = 16]) and continuous response parameters (time on study [TOS], mean = 59 days: range = 8-196 days) were performed. For cell lines, whole genome RNASeq data was generated from 14 cell lines (MLL-r or MLL-PTD) with a range of in vitro sensitivity to pinometostat (cell proliferation IC50 2 nM to > 10 μM) and RNA transcripts identified as correlated with IC50 were submitted for pathway analysis. Univariate analyses revealed no DNA variants to be associated with either response category (FDR adjusted P MLL-r fusion partner (e.g. t(11:19)) may influence clinical response to pinometostat. In addition RNASeq based characterization of patient samples and cell lines revealed candidate pathways that may cooperate with or antagonize pinometostat activity that warrant further investigation. Citation Format: Scott Daigle, Alice McDonald, Ty M. Thomson, David A. Drubin, Michael Maria, A. Carson, Brad Patay, Jeff Keats, Christine Klaus, Alejandra Raimondi, G. Garcia-Manero, D. A. Rizzieri, Raoul Tibes, Jesus Berdeja, Eytan M. Stein, Blythe Thomson, Stephen J. Blakemore. Identification of biomarkers and pathways associated with response to the DOT1L inhibitor Pinometostat (EPZ-5676) in MLL-r leukemia. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr C12.

Abstract 2701: Characterization of acquired EPZ-5676 resistance in cell line models of MLL rearranged leukemia

DOT1L inhibitor EPZ-5676 is currently under Phase 1 clinical trial investigation in relapsed/refractory patients with acute leukemia, including those with an MLL-rearrangement (MLL-r). Early clinical results, including complete remissions, support ongoing clinical development and preclinical investigation into mechanisms precipitating EPZ-5676 treatment induced resistance. MLL-r cell lines KOPN-8 (MLL-ENL) and NOMO-1 (MLL-AF9) were exposed to an EPZ-5676 concentration above the pre-determined 14 day proliferation assay IC90. Initial treatment of the cell lines led to the expected inhibition of H3K79 dimethylation (H3K79me2) and MLL-r target genes HOXA9 and MEIS1 as outlined in previous work (Daigle et al, Cancer Cell 2011). Resistance to EPZ-5676 in both cell lines emerged following three weeks of continued treatment with EPZ-5676 and was defined by increased growth rates in the presence of inhibitor. Mechanisms of resistance for both cell lines were investigated using RNASeq and ChIPSeq on parental and resistant cell line pools. Our analysis identified common characteristics between the resistant cell lines, but mechanisms by which they became resistant differed. Global H3K79me2 inhibition was maintained in both refractory cell lines, yet ChIP-seq analysis of resistant pools identified specific loci with H3K79me2 recovery in KOPN-8 cells. In resistant KOPN-8 cells recovery of H3K79me2 was concentrated at the HOXA locus and other MLL-r target genes (e.g. MEIS1 and RUNX2), with the remainder of actively transcribed genes maintaining H3K79me2 inhibition at levels observed in parental cells. In contrast, resistant NOMO-1 cells did not recover H3K79me2 at any actively transcribed genes, including those of the MLL-r signature. Only resistant KOPN-8 cells regained expression of the MLL-r target genes HOXA9 and MEIS1. Of note both resistant NOMO-1 and KOPN-8 cell lines had 8 and 40 fold upregulation of the ABCB1 (MDR1, P-gp) tranporter respectively when compared to a matched control cell line. To explore the role of drug efflux transporter ABCB1 on resistance, we treated cells with Valspodar, a known inhibitor of ABCB1. Following treatment with 1 μM Valspodar, KOPN-8 cells showed decreased cell growth similar to the naive control cell line. Supporting the presence of an alternative resistance mechanism in NOMO-1 cells in addition to MDR1 upregulation, NOMO-1 cells remained resistant upon Valspodar treatment. Detailed gene expression and pathway analysis will be presented supporting mechanisms of treatment emergent resistance to EPZ-5676. In summary, we have identified two mechanisms of EPZ-5676 resistance in MLL-r cell lines, one mechanism dependent on and the other independent of ABCB1. Further refinement of these mechanisms will aid in providing hypotheses for testing mechanisms of EPZ-5676 treatment emergent resistance in patients and may support designing future rational clinical combinations. Citation Format: Scott R. Daigle, Carly T. Campbell, Nigel J. Waters, Edward J. Olhava, Robert A. Copeland, Stephen J. Blakemore, Roy M. Pollock, Jesse J. Smith. Characterization of acquired EPZ-5676 resistance in cell line models of MLL rearranged leukemia. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2701. doi:10.1158/1538-7445.AM2015-2701

Abstract 312: Evidence of EZH2 dependent and independent mechanisms of tazemetostat treatment emergent resistance in models of diffuse large B cell lymphoma

Tazemetostat is a small molecule inhibitor of the histone methyltransferase EZH2 and is currently in phase 2 clinical trials including relapsed refractory Non-Hodgkin Lymphomas (RR-NHL) Diffuse Large B Cell Lymphoma and Follicular Lymphoma. In the phase 1 clinical trial RR-NHL patients demonstrated positive clinical activity with a favorable safety profile. Acquired mutations in the D1 domain (I109K, Y111D, Y111L) and the SET domain (Y661D) of EZH2 have recently been reported as a mechanism of resistance to non-tazemetostat small molecule EZH2 inhibition. Given the clinical activity observed in the phase 1 tazemetostat clinical trial and these reports of pre-clinical EZH2 inhibitor induced resistance we embarked on investigations of the potential of tazemetostat to induce resistance in NHL cell lines. An EZH2 Y641F mutant DLBCL cell line WSU-DLCL2 was exposed to 1 μM tazemetostat, a dose which is 100 fold greater than the naive line9s 11 day growth IC50. After 8 weeks, growth of the tazemetostat treated cells matched that of the control cells. Subsequent increases in dose of tazemetostat up to 10 μM did not yield any changes in growth rate of the treated cells. EZH2 wild-type PMBCL cell line U2940 was exposed to a step wise increase in tazemetostat concentration for 7 weeks and finally maintained at the naive cell line 11 day proliferation IC50 of 10 μM, with minimal effects on cell growth. Tazemetostat resistant cell lines were screened for acquired EZH2 mutations using a full coding next generation sequencing assay, with a mean depth of 17,126 across all positions. Sequencing results showed the resistant U2940 had gained mutations in EZH2 similar to those previously identified, a heterozygous Y661N mutation and a low frequency mutation of Y111H, consistent with a subclonal mutation. These acquired mutations have been reported to interfere with the binding of EZH2 inhibitors, which supports the minimal reduction of H3K27me3 as measured by ELISA in the resistant U2940 after treatment with tazemetostat. In contrast, after induction of tazemetostat resistance WSU-DLCL2 retained equipotent sensitivity to reduction of H3K27me3 by ELISA. Correspondingly, sequencing of EZH2 in the resistant WSU-DLCL2 line did not identify any additional mutations. These findings suggest continued target engagement with tazemetostat in the resistant WSU-DLCL2, and that a novel bypass mechanism may be engaged to confer resistance. In an attempt to identify the mechanism of resistance in the WSU-DLCL2 line, whole exome sequencing and RNA sequencing has been performed. Detailed mutational, gene expression and pathway analysis will be performed on these data to investigate mechanisms of treatment emergent resistance to tazemetostat. Understanding these mechanisms may guide hypotheses for rational combinations and provide direction for future preclinical and potentially clinical studies. Citation Format: Carly T. Campbell, Jeff S. Jasper, Scott R. Daigle, Scott A. Ribich, Heike Keilhack, Jesse S. Smith, Peter T. Ho, Stephen J. Blakemore. Evidence of EZH2 dependent and independent mechanisms of tazemetostat treatment emergent resistance in models of diffuse large B cell lymphoma. [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 312.

Abstract 137: Development and application of a 62-gene panel for assessment of somatic sequence and structural variants in tumor DNA derived from non-Hodgkin lymphoma patients treated in a phase 1 clinical trial with the EZH2 inhibitor tazemetostat

Tazemetostat is a small molecule inhibitor of the histone methyltransferase EZH2 and is currently in phase 2 clinical trials in relapsed refractory Non-Hodgkin9s Lymphomas (RR-NHL) including diffuse large B cell and follicular lymphoma. We report the development and application of a NHL targeted sequencing panel designed to identify molecular variants, including specific somatic sequence mutations (single base and insertion/deletion), amplifications and translocations in both tumor and cell free circulating tumor DNA (ctDNA). Analysis of somatic alterations in both tissue and ctDNA collected pre-dose enables determination of molecular variants that may correspond with clinical activity, while longitudinal analysis of ctDNA sampled on therapy could help monitor patients for minimal residual disease and emergence of acquired resistance. In collaboration with Personal Genome Diagnostics (PGDx) a panel of 62 NHL specific genes was designed to selectively analyze regions of the genome previously identified as somatically altered in NHL. DNA derived from matched tumor tissue and plasma were screened utilizing this panel using the Illumina HiSeq 2500 platform with 100 bp paired-end reads. Average target coverage for the tissue panel was 1,250-fold while coverage for the ctDNA was approximately 20,000-fold and 3,700-fold for sequence mutations and structural alterations, respectively. Data were analyzed using PGDx9s validated cancer genome analysis algorithms that allow for reliable identification of mutations with high sensitivity and specificity. Validation of both the tumor and ctDNA panels was performed using tumor and plasma specimens previously characterized for sequence mutations, amplifications, translocations, and microsatellite instability. For archive tumor, analyses of cell line specimens with an experimental tumor purity of 20-100% using 50-100ng of DNA yielded sensitivity and specificity of 100% for detection of 358 previously characterized sequence mutations and structural variants. Similar ctDNA analyses using fragmented cell line and plasma derived DNA with an experimental tumor purity of 0.10%-25.0% using 9-167ng of DNA yielded a sensitivity of 100% for detection of over 100 genetic variants. Following successful validation of the panel we proceeded to sequence tumor tissue from 11 patients and ctDNA from 16 NHL patients enrolled in the tazemetostat phase 1 clinical trial. Tumor tissue from these patient samples had been previously sequenced using a smaller 39 gene panel. We observed high concordance with 100% of variants detected within the shared gene set of 33 genes between the historic data and our new 62 gene panel. We will report the landscape and concordance of genetic alterations identified through next-generation sequencing analyses of tumor and cell-free DNA. Citation Format: Scott R. Daigle, Samuel Angiuoli, Sian Jones, Scott Ribich, Heike Keilhack, Mark Sausen, Peter T. Ho, Stephen J. Blakemore. Development and application of a 62-gene panel for assessment of somatic sequence and structural variants in tumor DNA derived from non-Hodgkin lymphoma patients treated in a phase 1 clinical trial with the EZH2 inhibitor tazemetostat. [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 137.