Virtual Library

Start Your Search

P. Mack



Author of

  • +

    MA16 - Novel Strategies in Targeted Therapy (ID 407)

    • Event: WCLC 2016
    • Type: Mini Oral Session
    • Track: Chemotherapy/Targeted Therapy/Immunotherapy
    • Presentations: 1
    • +

      MA16.10 - Lung-MAP (S1400) Lung Master Protocol: Accrual and Genomic Screening Updates (ID 3995)

      14:20 - 15:50  |  Author(s): P. Mack

      • Abstract
      • Presentation
      • Slides

      Background:
      Lung-MAP (S1400), is a master protocol that incorporates genomic testing of tumors through a next generation sequencing (NGS) platform (Foundation Medicine) and biomarker-driven (matched) therapies for patients with squamous cell lung cancer (SCCA) after progression on first-line chemotherapy.

      Methods:
      The Lung-MAP trial, activated June 16, 2014, includes 3 matched- and 1 non-match study. Matched studies include: S1400B evaluating taselisib, a PI3K inhibitor, S1400C evaluating palbociclib, a CDK 4/6 inhibitor and, S1400D evaluating AZD4547, an FGFR inhibitor. The non-match study S1400I tests nivolumab + ipilimumab vs. nivolumab. Two studies have closed: S1400E evaluating rilotumumab an HGF monoclonal antibody + erlotinib closed 11/26/2014 and S1400A evaluating MEDI4736 in non-match pts, closed 12/18/2015.

      Results:
      From June 16, 2014 to June 15, 2016, 812 pts were screened and 292 pts registered to a study: 116 to S1400A, 27 to S1400B, 53 to S1400C, 32 to S1400D, 9 to S1400E and 55 to S1400I. Demographics: Screening was successful for 705 (87%) of screened eligible pts. Median age 67 (range 35-92); male 68%; ECOG PS 0-1 88%, PS 2 10%; Caucasian 85%, Black 9%, other 5%; never/former/current smokers 4%/58%/36%. Table 1 displays biomarker prevalence; 39% of pts matched; 33.9%, 4.8%, and 0.3% with 1, 2, and all 3 biomarkers, respectively. Tumor mutation burden (TMB) was available for 636 (90.4%) of eligible pts. The distribution of TMB is: 126 (19.8%) low (≤5 mutations Mb), 415 (65.1%) intermediate (6-19 mutations/Mb), and 96 (15.1%) high (≥20 mutations/Mb). The median TMB was 10.1.

      Conclusion:
      Genomic screening is feasible as part of this master protocol designed to expedite drug registration, confirm anticipated prevalence of targeted alterations in SCCA and reveal intermediate or high TMB in most (80.2%) pts. Treatment results are not yet available as patients continue to accrue. Clinical trial information: NCT02154490

      Total FGFR CDK PIK3CA
      FGFR (15.9%) 12.9% 2.4% 0.6%
      CDK (18.8%) 14.6% 1.8%
      PIK3CA (8.8%) 6.4%
      Biomarker prevalence and overlap.


      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    OA06 - Prognostic & Predictive Biomarkers (ID 452)

    • Event: WCLC 2016
    • Type: Oral Session
    • Track: Biology/Pathology
    • Presentations: 1
    • +

      OA06.01 - Clinical Utility of Circulating Tumor DNA (ctDNA) Analysis by Digital next Generation Sequencing of over 5,000 Advanced NSCLC Patients (ID 6096)

      14:20 - 15:50  |  Author(s): P. Mack

      • Abstract
      • Presentation
      • Slides

      Background:
      Detection of actionable genomic alterations is now required for NCCN guideline-compliant work-up of NSCLC adenocarcinoma. Next-generation sequencing (NGS) of ctDNA, if sufficiently sensitive and specific, could provide a non-invasive, comprehensive genotyping platform relevant to clinical decision-making when tissue is insufficient or at time of progression on targeted therapies.

      Methods:
      A highly accurate, deep-coverage (15,000x) ctDNA plasma NGS test targeting 54-70 genes (Guardant360) was used to genotype 5,206 advanced-stage NSCLC patients accrued between 6/2014 – 4/2016. The frequency and distribution of somatic alterations in key genes were compared to those described in TCGA (Pearson and Spearman correlations). The clinical impact of ctDNA testing was evaluated by identification of resistance mechanisms emergent at progression on targeted therapies, and through analysis of additional driver mutations detected by ctDNA at baseline in 362 consecutive NSCLC patients with tissue mutation data available. The positive predictive value (PPV) of ctDNA sequencing was assessed in 229 patients with known tumor driver alterations.

      Results:
      ctDNA alterations were detected in 86% of cases; EGFR mutations in 25%, KRAS mutations in 17%, MET amplification in 4%, BRAF mutations in 3% and other rare but potentially actionable alterations in 9%. Mutation patterns among driver oncogenes were highly consistent with those from TCGA (Pearson r=0.92, 0.99, 0.99 for EGFR, KRAS, and fusion breakpoint location). PPV of ctDNA-detected variants was 100% for EGFR[L858R], 98% for EGFR[E19del], 96% for ALK, RET, or ROS1 fusions, and 100% for KRAS[G12/G13/Q61] mutations. In 362 cases with tissue information available, 63% (229/362) were tissue quantity-insufficient or undergenotyped (QNS/UG). ctDNA analysis identified driver mutations in 51 of the 229 QNS/UG cases, a 38% increase in detection rate over tissue alone. Among 1,111 EGFR-mutant cases, resistance mutations were identified at progression at frequencies consistent with published literature: EGFR[T790M] 47%, MET amp 5%, ERBB2 amp 5%, FGFR3 fusions 0.4%, ALK/other fusions 1%, BRAF mutations 1.8%, PTEN inactivation 2.5%, NF1 inactivation 3%, RB1 inactivation 3%, KRAS mutations 1.9%. In 143 consecutive NSCLC patients with detailed follow-up and serial analysis seen at the UC Davis Cancer Center, informative driver mutations were observed in 48 (34%).

      Conclusion:
      This series represents the largest NSCLC ctDNA study to date. Genotypic patterns of truncal mutations were highly consistent with TCGA in terms of frequency and distribution. At baseline, ctDNA augmented tissue analysis by identifying additional, actionable mutations when tissue was QNS/UG. ctDNA NGS conducted at progression identified emergent resistance mutations that could inform subsequent courses of therapy.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    OA10 - EGFR Mutations (ID 382)

    • Event: WCLC 2016
    • Type: Oral Session
    • Track: Biology/Pathology
    • Presentations: 1
    • +

      OA10.01 - Comprehensive Genomic Profiling and PDX Modeling of EGFR Exon 20 Insertions: Evidence for Osimertinib Based Dual EGFR Blockade (ID 4375)

      11:00 - 12:30  |  Author(s): P. Mack

      • Abstract
      • Slides

      Background:
      EGFR exon 20 insertion mutations (EGFRex20ins) comprise a subset of EGFR activating alterations relatively insensitive to 1[st] and 2[nd] generation EGFR-TKIs. Comprehensive genomic profiling (CGP) integrated with PDX modeling may identify new EGFR-inhibition strategies for EGFRex20ins.

      Methods:
      EGFRex20ins and co-occurring genomic alterations were identified by hybrid-capture based CGP performed on 14,483 consecutive FFPE lung cancer specimens to a mean coverage depth of >650X for 236 or 315 cancer-related genes plus 47 introns from 19 genes frequently rearranged in cancer. An EGFRex20ins(N771_P772>SVDNP)/EGFR-amplified tumor (24 copies) from this cohort was implanted subcutaneously into the flank of NOD.Cg-Prkdc[scid]Il2rg[tm1Wjl]/SzJ (NSG) mice for tumor growth inhibition studies (TGI) with vehicle, erlotinib (50 mg/kg PO daily), osimertinib (25 mg/kg PO daily), and osimertinib (25 mg/kg PO daily) plus cetuximab (10 mg/kg IV, 2x/week) administered for 21 days.

      Results:
      CGP identified 263/14,483 cases (1.8%) with EGFRex20ins, which represent 12% (263/2,251) of EGFR activating mutations in this series. 90% (237/263) were NSCLC-adenocarcinoma, 9% (23/263) were NSCLC-NOS, and 1% (2/263) were sarcomatoid carcinoma. Over 60 unique EGFRex20ins were identified, most commonly D770_N771>ASVDN (21%) and N771_P772>SVDNP (20%); 6% (15/263) harbored EGFR A763_Y764insFQEA, an EGFRex20ins typically sensitive to erlotinib. Among EGFRex20ins cases, EGFR-amplification occurred in 22% (57/263). Putative co-occurring driver alterations including EGFR (ex19del and L858R), Her2, MET and KRAS tended to be mutually exclusive, occurring only in 5% (12/263) of cases. The most common co-occurring alterations affected TP53 (56%), CDKN2A (22%), CDKN2B (16%), NKX2-1 (14%) and RB1 (11%). Average tumor mutation burden was low (mean 4.3 mutations/Mb, range 0-40.3 mutations/Mb). Clinical outcomes to 1st and 2nd generation EGFR-TKIs were obtained for a subset of cases with various EGFRex20ins, and 0/6 patients had responses. However, robust TGI was observed with combination osimertinib and cetuximab in a highly EGFR-amplified PDX model with a conserved EGFRex20ins (N771_P772>SVDNP) not associated with response to earlier generation EGFR-TKI, and was superior to vehicle, erlotinib or osimertinib alone (D21 mean tumor size 70 mm[3] vs. 1000, 800, 225 mm[3] respectively; p-values all <0.001).

      Conclusion:
      Diverse EGFRex20ins were detected in 12% of EGFR-mut NSCLC. Available clinical outcomes data demonstrated lack of response to 1[st] and 2[nd] generation EGFR-TKIs. Identification of co-occurring EGFR-amplification in 22% of cases led to testing of a dual EGFR blockade strategy with an EGFR monoclonal antibody and osimertinib, which demonstrated exceptional tumor growth inhibition in an EGFRex20ins PDX minimally responsive to erlotinib. These findings can rapidly be translated into an ongoing clinical trial of osimertinib and necitumumab.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P2.03b - Poster Session with Presenters Present (ID 465)

    • Event: WCLC 2016
    • Type: Poster Presenters Present
    • Track: Advanced NSCLC
    • Presentations: 1
    • +

      P2.03b-053 - Role of KRAS Mutation Status in NSCLC Patients Treated on SWOG S0819, a Phase III Trial of Chemotherapy with or without Cetuximab (ID 6113)

      14:30 - 15:45  |  Author(s): P. Mack

      • Abstract

      Background:
      The S0819 phase III study of chemotherapy and bevacizumab (by patient/physician choice) with or without cetuximab in NSCLC showed no benefit from the addition of cetuximab, either overall or within the EGFR FISH-positive subset. Secondary analysis suggested an overall survival benefit in EGFR FISH-positive squamous cell carcinoma (SCC) (Herbst WCLC 2015, Hirsch ASCO 2016). In colorectal cancer (CRC), benefit from EGFR monoclonal antibodies such as cetuximab is limited to patients with RAS wild type (WT) tumors; however, in NSCLC, previous studies have not been sufficiently powered to make this determination. We prospectively incorporated KRAS mutation testing in S0819 to determine whether it predicts cetuximab efficacy. Since KRAS mutations are rare in SCC, we focused this analysis on nonSCC.

      Methods:
      KRAS mutation status was determined using the Therascreen KRAS test (Qiagen), conducted in a CLIA-certified diagnostic laboratory at the UC Davis Comprehensive Cancer Center. This test is FDA-approved for KRAS diagnostics in metastatic CRC, and identifies 6 mutations at codon 12 (G12A,D,R,C,S,V) plus G13D.

      Results:
      KRAS mutation status was available for 448 nonSCC patients, and mutations were identified in 150 cases (33%). Amino acid substitutions matched the expected distribution for a NSCLC population, with 52% harboring G12C and 17% with G12V. No significant differences were observed between KRAS-mut and WT populations for PFS (HR=1.15 (0.94-1.42); p=0.18) or OS HR=1.10 (0.89-1.37); p=0.39). Furthermore, no differences in outcomes between arms were observed based on KRAS mutation status (Table). The KRAS WT, EGFR FISH+ molecular subset (hypothetically the most likely subgroup to benefit from cetuximab) showed no statistical differences in outcomes between arms. Figure 1



      Conclusion:
      Determination of KRAS mutation status did not identify a subgroup of nonSCC patients with differential outcome from addition of cetuximab to front-line chemotherapy. In contrast to CRC, cetuximab does not appear to confer benefit to patients with KRAS-WT nonSCC NSCLC.

  • +

    SC21 - Predictive Biomarkers for Outcome of Systemic Therapy in NSCLC (ID 345)

    • Event: WCLC 2016
    • Type: Science Session
    • Track: Biology/Pathology
    • Presentations: 1
    • +

      SC21.05 - Emerging Role of Liquid Biopsies in NSCLC (ID 6689)

      16:00 - 17:30  |  Author(s): P. Mack

      • Abstract
      • Presentation
      • Slides

      Abstract not provided

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.