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Pretreatment and serial plasma assessments of
Pretreatment and serial plasma assessments of EGFR mutations in NSCLC patients treated with rociletinib (CO-1686) Jonathan Goldman, Chris Karlovich, Elaina Mann, Lindsey Rolfe, Shannon Matheny, Darrin Despain, Philipp Angenendt, Claudia Stamm, Heather Wakelee, Jean-Charles Soria, Benjamin Solomon, D. Ross Camidge, Rafal Dziadziuszko, Leora Horn, Shirish Gadgeel, Mitch Raponi, Andrew Allen, Lecia Sequist 2 Disclosure Information: Jonathan Goldman, MD AACR Annual Meeting 2015 I have the following financial relationships to disclose: • Consultant for: Clovis • Grant/Research support from: Clovis, MedImmune, BMS, Lilly, Astra Zeneca 3 Lung adenocarcinoma is increasingly treated according to driver mutation • Activating mutations (eg, del 19, L858R) in EGFR found in ≈15% of all NSCLC – Lung adenocarcinoma oncogene drivers Twice as common in East Asian populations • A first-generation EGFR inhibitor (EGFRi) is often used as first- or later-line therapy after chemotherapy • T790M found in >60% of acquired resistance to first-generation EGFRi • Rociletinib (CO-1686) is a novel, oral, selective covalent inhibitor of EGFR mutations in NSCLC – Inhibits key activating and T790M mutations – Spares wild-type (wt) receptor signaling EGFR=epidermal growth factor receptor; NSCLC=non-small cell lung cancer. Blakely CM, Bivona TG. Cancer Discov. 2012;2:872-875; Yu HA, et al. Clin Cancer Res 2013;19:2240–2247 4 TIGER-X clinical dose group responses Change from Baseline (%) 100 Best Response for Evaluable T790M+ Patients 67% ORR (per RECIST v1.1) 89% DCR 80 60 40 20 0 -20 -40 -60 -80 -100 • US FDA breakthrough therapy designation granted May 2014 • Several global phase 2/3 trials are underway or about to start in both first-line and later-line Soria et al. Presented at EORTC-NCI-AACR; November 18–21, 2014; Barcelona, Spain. 5 Mutations missed by tissue test because of tumor heterogeneity may be captured by a blood test EGFR-mutant NSCLC Response T790M-mediated relapse: candidate for rociletinib First-generation EGFRi EGFR-activating mutation EGFR-activating mutation plus T790M resistance mutation blood • Adapted from N. Rosenfeld/D. Tsui Reservoir for cancer genome in circulating tumor (ct)DNA biopsy • May miss T790M 6 An EGFR blood test would be advantageous but needs high sensitivity/specificity for use in clinical practice • Why blood? – Tumor heterogeneity – Biopsies can be difficult/insufficient – Inadequate/insufficient material for molecular analysis in 10%–20% of clinical cases Comorbidities prevent biopsies in ≤20% of patients blood Minimally invasive • In January 2015, EMA approved blood testing for activating mutations (L858R and del 19) to guide treatment decisions with gefitinib EGFR-activating mutation EMA=European Medicines Agency. EGFR-activating mutation plus T790M resistance mutation 7 Quantitative and sensitive BEAMing test (Sysmex Inostics) is being used for EGFR mutation detection in plasma Pre-amplification Emulsion PCR & hybridization Flow cytometry Magnetic beads coated with primer DNA isolation Amplified DNA Water-in-oil emulsion Plasma Tumor DNA Wild-type DNA dNTPs Polymerase Primer Oil-emulsifier mixture • BEAMing is digital PCR followed by flow cytometry – EGFR test identifies L858R, del 19, and rare activating mutations plus T790M dNTPs=deoxynucleotide triphosphates; PCR=polymerase chain reaction. Dressman D et al. Proc Natl Acad Sci U S A. 2003;100:8817-8822; Diehl F et al. Proc Natl Acad Sci U S A. 2005;102:16368-16373. 8 Low mutant EGFR levels in substantial fraction of NSCLC patients support need for highly sensitive detection mutant molecules/mL plasma Pretreatment plasma 1000000 100000 • EGFR testing performed on matched pretreatment tissue and plasma (BEAMing) for 247 patients from TIGER-X trial 10000 1000 • 20 (8.1%) not evaluable in tissue due to low/no tumor content or poor sample quality 100 10 1 0.1 EGFR molecules/mL in plasma by BEAMing Activating mutations T790M Median = 93 Range = 0–324,399 N = 251 Median = 24 Range = 0–227,994 N = 235 • Plasma and tissue collections matched in time 9 Comparison of plasma and tissue: BEAMing shows very good sensitivity and identifies patients missed by tissue test Tissue Activating mutations T790M Positive Negative Inadequate tissue Positive 193 4 14 211 155 23 12 190 Negative 28 2 6 36 37 12 8 57 221 6 20 247 192 35 20 247 Plasma Total Tissue as reference: Positive percent agreement Total Positive Activating 87% (193/221) Negative Inadequate tissue Total T790M 81% (155/192) • T790M plasma+/tumor- patients very likely true positives and reflect tumor heterogeneity – 5 of 7 tested were confirmed plasma+ by Cobas or Boreal tests • BEAMing plasma test almost identified as many T790M+ patients (190) as did tissue test (190) when inadequate tissue specimens (n=20) were included in analysis (n=247) 10 Comparative data suggest ≈20%–30% of T790M tissue positives are not detected in plasma by any method Patient 1 2 3 4 5 6 7 8 9 10 11 12 13 Tissue T790M ND ND Detected Detected Detected Detected Detected Detected Detected Detected Detected Detected ND BEAMing Plasma Copies/ T790M mL % ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND Detected 1 0.05 Detected 1 0.07 Detected 6 0.35 Detected 9 1.1 Detected 14 0.4 Detected 29 0.9 Cobas Plasma T790M ND ND ND ND ND ND Detected ND Detected Detected Detected Detected Detected ddPCR Plasma Copies/ T790M mL ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND Detected 32 Detected 12 Detected 20.5 Detected 275 % ND ND ND ND ND ND ND ND ND 1.1 0.5 0.3 1.1 Boreal OnTarget Plasma Copies/ T790M mL % ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND Detected 3 0.15 Detected 2 0.08 Detected 15 0.38 Detected 18 1.4 Detected 11 0.2 Detected 10 0.4 • The various platforms performed similarly for most samples • NSCLC biology, rather than sensitivity of detection method, is likely limiting factor ddPCR=Droplet Digital PCR; ND=not detected. 11 Mutations are more readily detected in plasma of patients with distant metastatic (M1b) vs intrathoracic (M1a) disease Mutation Mutation detected Disease in tissue and/or classification plasma M0/M1a 63 Subset with mutation in plasma by BEAMing Percentage 40 63% T790M <0.001 M1b Mutation Activating Mutations P value 170 Mutation detected Disease in tissue and/or classification plasma M0/M1a 60 161 95% Subset with mutation in plasma by BEAMing Percentage 30 50% P value <0.001 M1b 164 151 91% 12 Change in EGFR-activating mutation plasma levels by day 21 may predict clinical benefit to rociletinib 1000 100 10 21 ay as e B D ay lin e 8 1 21 ay lin e B as e ay D Plasma Collection Day Activating Mutation 10000 D EGFR act mut (molecules/mL) 1 21 8 ay D lin e 1 10 D 10 100 8 100 1000 ay 1000 10000 D EGFR act mut (molecules/mL) 10000 as e PD SD B EGFR act mut (molecules/mL) PR Plasma Collection Day Activating Mutation Plasma Collection Day Activating Mutation • A drop to <10 copies/mL in EGFR-activating mutation levels was observed by day 21 in all but 1 patient who went on to have PRs • A similar drop was seen in T790M plasma levels in patients with PRs • EGFR-activating mutation levels remained high in most patients with PD PD=progressive disease; PR=partial response; SD=stable disease. 13 Changes in ctDNA mirror clinical response to rociletinib; progression may or may not be preceded by reemergence of plasma mutEGFR 50 100 40 30 10 20 10 1 N/D 0 -30 0 60 120 180 240 300 360 420 480 540 80 1000 60 100 40 10 20 1 N/D 0 -30 0 60 Study Day SLD T790M 120 180 240 300 50 10000 40 1000 30 100 20 10 10 360 1 N/D 0 -30 0 60 120 180 240 300 360 420 480 Study Day Del 19 Still on study SLD T790M Copies/mL Plasma 1000 60 10000 Sum of Target Lesions (mm) 70 100 Copies/mL Plasma 10000 Sum of Target Lesions (mm) 80 Best Overall Response: PR Best Overall Response: PR Copies/mL Plasma Sum of Target Lesions (mm) Best Overall Response: PR Study Day L858R Re-emergence of mutEGFR 17 ½ wks prior to clinical progression SLD T790M Del 19 M1a pt with no re-emergence of mutEGFR in plasma 14 Tissue negative/plasma positive patient with excellent outcome • 30 yr old male • Progressed on front line gefitinib (15 months) immediately before rociletinib • Tumor in thorax, brain, supraclavicular nodes (readily accessible for bx) • Negative T790M by local and central tissue testing • Plasma T790M positive by BEAMing • RECIST PR at cycle 2 (including biopsied node), maintained for 10 cycles BASELINE CYCLE 4 15 Summary • Low plasma T790M level in many NSCLC patients supports the use of sensitive technologies such as BEAMing for mutation detection • BEAMing plasma test identified almost as many T790M+ patients as the tissue test when inadequate tissue specimens were included in the analysis • Plasma testing and tissue testing appear to be complementary techniques for identifying patients for T790M inhibitors – Reflex testing of plasma before tumor could be considered • Mutations were more readily detectable in the plasma of patients with M1b rather than M1a disease • Change in EGFR-activating mutation plasma levels by day 21 may predict clinical benefit to rociletinib 16 Acknowledgments All of the Phase I and TIGER-X Investigators Qiagen Sysmex/Inostics Clovis Oncology Jonathan Perkins Philipp Angenendt Chris Karlovich Judith Finlayson Claudia Stamm Mitch Raponi Sheila Smart Sarah Clausdorf Andrew Allen Vishal Sikri Elaina Mann Roche Molecular Systems Rachel Fernald Onkar Dha Wen Wei Frank Diehl Lindsey Rolfe Lin Wu Jason Litten Patrick O’Donnell Shannon Matheny Sean Chien Darrin Despain Jeff Isaacson Andy Simmons Tom Harding Cynthia Voong Lisa Caunt 17
