Validated and promising predictive factors in mcrc: Recent updates on RAS testing Fotios Loupakis, MD PhD U.O. Oncologia 2 Universitaria Azienda Ospedaliero-Universitaria Pisana Pisa, Italy
Learning Objectives Why and how did molecular testing in mcrc change? Implications for RAS testing in clinical practice? New perspectives for RAS testing? 15/06/2015 2
The beginning of KRAS story Phase III CA225025 trial: Cet vs. BSC in advanced lines Phase III 20020408 trial: Pan vs. BSC in advanced lines Jonker et al. N Engl J Med 2007 Van Cutsem et al. J Clin Oncol 2007 Phase III trials comparing anti-egfr monotherapy vs. BSC suggested a «subgroup effect» with regard to the benefit from Cet and Pan 15/06/2015 3 Jonker DJ et al. N Engl J Med 2007;357(20):2040-2048. Reproduced with permission of Massachusetts Medical Society in the format Use in an e- coursepack via Copyright Clearance Center; Van Cutsem E et al. J Clin Oncol 2007;25(13):1658-1664. Reprinted with permission. (2007) American Society of Clinical Oncology. All rights reserved
The first clinical report In a small retrospective cohort, KRAS exon 2 mutations seemed to predict resistance to anti-egfrs 15/06/2015 4 Reprinted from Lièvre A et al. Cancer Res 2006;66(8):3992-3995, with permission from AACR
Post-hoc analyses of phase III trials KRAS exon 2 wt Jonker DJ et al. N Engl J Med 2007 KRAS exon 2 mut Karapetis CS et al. N Engl J Med 2008 Benefit from cetuximab was restricted to KRAS exon 2 wt population 15/06/2015 5 Jonker DJ et al. N Engl J Med 2007;357(20):2040-2048. Reproduced with permission of Massachusetts Medical Society in the format Use in an ecoursepack via Copyright Clearance Center; Karapetis CS et al. N Engl J Med 2008;359(17):1757-1765. Reproduced with permission of Massachusetts Medical Society in the format Use in an ecoursepack via Copyright Clearance Center
Post-hoc analyses of phase III trials KRAS exon 2 wt Van Cutsem E et al. J Clin Oncol 2007 Amado RG et al. J Clin Oncol 2008 KRAS exon 2 mut Benefit from panitumumab was restricted to KRAS exon 2 wt population 15/06/2015 6 Van Cutsem E et al. J Clin Oncol 2007;25(13):1658-1664. Reprinted with permission. (2007) American Society of Clinical Oncology. All rights reserved; Amado RG et al. J Clin Oncol 2008;26(10):1626-1634. Reprinted with permission. (2008) American Society of Clinical Oncology. All rights reserved
Benefit from anti-egfrs in the «KRAS exon 2-selected» population mpfs (mos) N Cet BSC HR p Unselected 572 1.9 1.8 0.68 <0.001 KRAS exon 2 wt 215 3.7 1.9 0.40 <0.001 KRAS exon 2 mut 151 1.8 1.8 0.99 NS Jonker DJ et al. N Engl J Med 2007;357(20):2040-2048; Karapetis CS et al. N Engl J Med 2008;359(17):1757-1765 mpfs (mos) N Pan BSC HR p Unselected 463 1.8 1.7 0.54 0.66 KRAS exon 2 wt 243 2.8 1.7 0.45 <0.001 KRAS exon 2 mut 184 1.7 1.7 0.99 NS Van Cutsem E et al. J Clin Oncol 2007;25(13):1658-1664; Amado RG et al. J Clin Oncol 2008;26(10):1626-1634 The magnitude of benefit from anti-egfr moabs is amplified 15/06/2015 7 in KRAS exon 2 wt population
KRAS exon 2: evidences in the 1 st line setting Phase III CRYSTAL trial: FOLFIRI +/- Cetuximab in 1 st line mpfs (mos) N FOLFIRI+Cet FOLFIRI HR p Unselected 1198 8.9 8.0 0.85 0.05 KRAS exon 2 wt 666 9.9 8.4 0.70 0.001 KRAS exon 2 mut 397 7.4 7.7 1.17 0.26 The magnitude of benefit from the addition of cetuximab to 1 st line FOLFIRI is amplified in KRAS exon 2 wt population Van Cutsem E et al. J Clin Oncol 2007;25(13):1658-1664
EMA Indications for anti-egfrs June 2008 9 By permission of the European Medicines Agency
KRAS mutations: the size of the problem KRAS exon 2 mutations affect about 40-45% of mcrc 15/06/2015 10 Data from the COSMIC database
Beyond KRAS exon 2 15/06/2015 11 Edkins S et al. Cancer Biol Ther 2006;5(8):928-932; Buhrman G et al. Structure 2007;15(12):1618-1629
Beyond KRAS exon 2 10% KRAS exon 3 and 4 mutations: constitutively activate RAS/RAF/MAPKs pathway occur in about 10% of mcrcs 15/06/2015 12 Edkins S et al. Cancer Biol Ther 2006;5(8):928-932; Buhrman G et al. Structure 2007;15(12):1618-1629
Beyond KRAS exon 2 10% 10% Other RAS mut: 20% NRAS exon 2-3-4 mutations: constitutively activate RAS/RAF/MAPKs pathway occur in about 10% of mcrcs Irahara N et al. Diagn Mol Pathol 2010;19(3):157-163; Vaughn CP et al. Genes Chromosomes Cancer 2011;50(5):307-312
Metastatic tumuor N= 107 pairs Primary tumuor RAS status: concordance between primary and metastases Prevalence of mutations tested* in 107 paired primary and metastatic tumour samples KRAS 89% NRAS 83% HIGH prim-mets CONCORDANCE for RAS status 15/06/2015 14 * Ion Torrent AmpliSeq Cancer Panel Adapted from and by permission of Kopetz S et al. J Clin Oncol ASCO 2014;32(15_suppl):3509
KRAS «rare» mutations: data from retrospective series Retrospective cohort of KRAS exon 2 wt pts treated with cetuximab plus irinotecan 15/06/2015 15 Reprinted by permission from Macmillan Publishers Ltd on behalf of Cancer Research UK: Loupakis F et al. Br J Cancer 2009;101(4):715-721
KRAS «rare» mutations: data from retrospective series Retrospective Consortium analysis in chemorefractory mcrc pts receiving cetuximab 250 222 200 150 100 123 Responders Non Responders KRAS cod 61 ORR: 0% mut vs. 35.7% wt p=0.006 50 0 KRAS codon 61 wt 0 13 KRAS codon 61 mut KRAS cod 146 ORR: 18.2% mut vs. 36.9% wt p=0.34 200 150 100 50 0 15/06/2015 16 101 173 KRAS codon 146 wt 2 9 KRAS codon 146 mut Responders Non Responders Adapted from De Roock W et al. Lancet Oncol 2010;11(8):753-762 (2010), with permission from Elsevier
NRAS mutations: data from retrospective series Retrospective Consortium analysis in chemorefractory mcrc pts receiving cetuximab 200 180 179 160 140 120 100 80 110 Responders Non Responders 60 40 20 0 NRAS wt 1 12 NRAS mut NRAS ORR: 7.7% mut vs. 38.1% wt OR 0.14, 95% CI 0.007-0.70; p=0.013 15/06/2015 17 Adapted from De Roock W et al. Lancet Oncol 2010;11(8):753-762 (2010), with permission from Elsevier
NRAS mutations: evidences from phase III trials Panitumumab vs. BSC in advanced lines PICCOLO trial: Irinotecan +/- Panitumumab in 2 nd line 15/06/2015 NRAS mutations may be potentially predictive of resistance to panitumumab Reprinted from Peeters M et al. Clin Can Res 2013;19(7):1902-1912, with permission from AACR; Seymour MT et al. Lancet Oncol 2013;14(8):749-759, by permission of Elsevier
The beginning of RAS story Phase III PRIME trial: FOLFOX +/- Panitumumab in 1 st line * *KRAS exon 2,3,4 and NRAS exon 2,3,4 Not only RAS mutant patients do not benefit from the addition of panitumumab to 1 st line FOLFOX, but may even derive a detrimental effect 15/06/2015 19 Douillard JY et al. N Eng J Med 2013;369(11):1023-1034. Reproduced with permission of Massachusetts Medical Society in the format Use in an e-coursepack via Copyright Clearance Center
PRIME trial: OS in RAS* wt * KRAS exon 2,3,4 and NRAS exon 2,3,4 wt 20.2 26.0 The magnitude of benefit from panitumumab is amplified by the extended molecular selection 15/06/2015 20 Douillard JY et al. N Eng J Med 2013;369(11):1023-1034. Reproduced with permission of Massachusetts Medical Society in the format Use in an e-coursepack via Copyright Clearance Center
OPUS trial: PFS according to RAS status Phase II OPUS trial: FOLFOX +/- Cetuximab in 1 st line RAS* wt HR: 0.43 [0.21-0.88] p=0.018 RAS* mut HR: 1.59 [1.08-2.36] p=0.018 The addition of cetuximab to 1 st line FOLFOX might be detrimental in patients with RAS mutations * KRAS 15/06/2015 exon 2,3,4 and NRAS exon 2,3,4 By permission of Tejpar S et al. J Clin Oncol ASCO GI 2014;32(3_suppl):LBA444
Benefit from anti-egfrs in the «RAS-selected» population in 1 st line setting (PFS) Phase III PRIME trial N FOLFOX+Pan FOLFOX HR p KRAS exon 2 wt 656 9.6 8.0 0.80 0.02 RAS wt 512 10.1 7.9 0.72 0.004 Phase II OPUS trial N FOLFOX+Cet FOLFOX HR p KRAS exon 2 wt 179 8.3 7.2 0.57 0.006 RAS wt 82 12.0 5.8 0.43 0.018 Phase III CRYSTAL trial N FOLFIRI+Cet FOLFIRI HR p KRAS exon 2 wt 666 9.9 8.4 0.70 0.0012 RAS wt 367 11.4 8.4 0.56 0.0002 The magnitude of benefit from the addition of an anti-egfr moab to 1 st line chemotherapy is amplified in RAS wt population 15/06/2015 22 Douillard JY et al. N Eng J Med 2013;369(11):1023-1034; Tejpar S et al. J Clin Oncol ASCO GI 2014;32(3_suppl):LBA444; Ciardiello F et al. J Clin Oncol ASCO 2014;32(3_suppl):LBA443; Ciardiello F et al. J Clin Oncol ASCO 2014;32(15_suppl):3506
Benefit from anti-egfrs in the «RAS-selected» population in 1 st line setting (OS) Phase III PRIME trial N FOLFOX+Pan FOLFOX HR p KRAS exon 2 wt 656 23.8 19.4 0.83 0.03 RAS wt 512 26.0 20.2 0.78 0.04 Phase II OPUS trial N FOLFOX+Cet FOLFOX HR p KRAS exon 2 wt 179 22.8 18.5 0.86 0.39 RAS wt 82 20.7 17.8 0.83 0.50 Phase III CRYSTAL trial N FOLFIRI+Cet FOLFIRI HR p KRAS exon 2 wt 666 23.5 20.0 0.80 0.0093 RAS wt 367 28.4 20.2 0.69 0.0024 The magnitude of benefit from the addition of an anti-egfr moab to 1 st line chemotherapy is amplified in RAS wt population 15/06/2015 23 Douillard JY et al. N Eng J Med 2013;369(11):1023-1034; Tejpar S et al. J Clin Oncol ASCO GI 2014;32(3_suppl):LBA444; Ciardiello F et al. J Clin Oncol ASCO 2014;32(3_suppl):LBA443; Ciardiello F et al. J Clin Oncol ASCO 2014;32(15_suppl):3506
New EMA indication for Panitumumab and Cetuximab August 2013 January 2014 15/06/2015 24 By permission of the European Medicines Agency
RAS: evidences from head-to-head trials Phase II PEAK trial: FOLFOX+Pan vs. FOLFOX+Bev in 1 st line mpfs (mos) N FOLFOX+Pan FOLFOX+Bev HR p KRAS exon 2 wt 285 10.9 10.1 0.87 0.353 RAS wt 170 13.0 9.5 0.65 0.029 KRAS exon 2 wt RAS wt 15/06/2015 25 Schwartzberg LS et al. J Clin Oncol 2014;32(21):2240-2247. Reprinted with permission. (2014) American Society of Clinical Oncology. All rights reserved
RAS: evidences from head-to-head trials Phase III FIRE-3 trial: FOLFIRI+Cet vs. FOLFIRI+Bev in 1 st line mpfs (mos) N FOLFIRI+Cet FOLFIRI+Bev HR p KRAS exon 2 wt 592 10.0 10.3 1.06 0.55 RAS wt 342 10.4 10.2 0.93 0.54 15/06/2015 26 By permission of Stintzing S et al. J Clin Oncol ASCO GI 2014;32(3_suppl):445
RAS: evidences from head-to-head trials Phase III CALGB/SWOG 80405 trial: Chemo+Cet vs. Chemo+Bev in 1 st line mpfs (mos) N Chemo+Cet Chemo+Bev HR p KRAS exon 2 wt 1137 10.4 10.8 1.04 0.55 RAS wt 526 11.4 11.3 1.10 0.31 KRAS exon 2 wt RAS wt 15/06/2015 By permission of Venook AP et al. J Clin Oncol ASCO 2014;32(3_suppl):LBA3; By permission of Lenz HJ et al. ESMO 2014
RAS: evidences from head-to-head trials Phase III CALGB/SWOG 80405 trial: Chemo+Cet vs. Chemo+Bev in 1 st line mos (mos) N Chemo+Cet Chemo+Bev HR p KRAS exon 2 wt 1137 29.9 29.0 0.93 0.34 RAS wt 526 32.0 31.2 0.90 0.40 KRAS exon 2 wt RAS wt By permission of Venook AP et al. J Clin Oncol ASCO 2014;32(3_suppl):LBA3; By permission of Lenz HJ et al. ESMO 2014 28
RAS: evidences in the 2 nd line setting Phase III 20050181 trial: FOLFIRI +/- Panitumumab in 2 nd line mpfs (mos) N FOLFIRI+Pan FOLFIRI HR p KRAS exon 2 wt 597 5.9 3.9 0.73 0.004 RAS wt 415 6.4 4.4 0.70 0.006 15/06/2015 By permission of Peeters M et al. J Clin Oncol ASCO GI 2014;32(3_suppl):LBA387
RAS: evidences in advanced lines Phase III 20020408 trial: Panitumumab vs. BSC in advanced lines mpfs (mos) N Pan BSC HR p KRAS exon 2 wt 243 2.8 1.7 0.45 <0.001 RAS wt 136 3.2 1.6 0.36 <0.001 KRAS exon 2 wt RAS wt 15/06/2015 30 By permission of Patterson SD et al. J Clin Oncol ASCO 2013;31(15_suppl):3617
What s next? BRAF! BRAF mutations affect 8-10% of mcrcs and about 15-20% of RAS wt tumours RAS mut all RAS wt BRAF mut 15/06/2015 31
BRAF mutation: prognostic impact Richman SD et al. J Clin Oncol 2009;27(35):5931-5937. Reprinted with permission. (2009) American Society of Clinical Oncology. All rights reserved Reprinted by permission from Macmillan Publishers Ltd on behalf of Cancer Research UK: Souglakos J et al. Br J Cancer 2009;101(3):465-472 2009 By permission of Koopman M. ESMO 2009 Reprinted by permission from Macmillan Publishers Ltd on behalf of Cancer Research UK: Yokota T et al. Br J Cancer 2011;104(5):856-862 2011 15/06/2015 32 Strong negative prognostic marker in mts setting
BRAF and anti-egfrs: evidences from retrospective series Retrospective analysis of BRAF mutation in mcrc KRAS wt pts treated with cetuximab or panitumumab 15/06/2015 33 Di Nicolantonio F et al. J Clin Oncol 2008;26(35):5705-5712. Reprinted with permission. (2008) American Society of Clinical Oncology. All rights reserved
BRAF and anti-egfrs: evidences from retrospective series Retrospective Consortium analysis in chemorefractory mcrc pts receiving cetuximab 250 200 202 150 124 Responders 100 50 0 BRAF wt 2 22 BRAF mut Non Responders BRAF ORR: 8.3% mut vs. 38.0% wt OR 0.17, 95% CI 0.02 0.51 p=0.0012 Adapted from De Roock W et al. Lancet Oncol 2010;11(8):753-762 (2010), with permission from Elsevier
BRAF and anti-egfrs: evidences from phase III trials PICCOLO trial: Irinotecan +/- Panitumumab in 2 nd line 15/06/2015 35 Seymour MT et al. Lancet Oncol 2013;14(8):749-759 (2013), with permission from Elsevier
BRAF and anti-egfrs: evidences from phase III trials CRYSTAL trial: FOLFIRI +/- Cetuximab in 1 st line Van Cutsem E et al. J Clin Oncol 2011;29(15):2011-2019. Reprinted with permission. (2011) American Society of Clinical Oncology. All rights reserved 36
BRAF and anti-egfrs: evidences from phase III trials PRIME trial: FOLFOX +/- Panitumumab in 1 st line Douillard JY et al. N Eng J Med 2013;369(11):1023-1034. Reproduced with permission of Massachusetts Medical Society in the format Use in an e-coursepack via Copyright Clearance Center 37
PRIME trial: RAS and BRAF selection mpfs (mos) N FOLFOX+Pan FOLFOX HR p KRAS exon 2 wt 656 9.6 8.0 0.80 0.02 RAS wt 512 10.1 7.9 0.72 0.004 RAS/BRAF wt 446 10.8 9.2 0.68 0.002 mos (mos) N FOLFOX+Pan FOLFOX HR p KRAS exon 2 wt 656 23.8 19.4 0.83 0.03 RAS wt 512 26.0 20.2 0.78 0.04 RAS/BRAF wt 446 28.3 20.9 0.74 0.02 Douillard JY et al. N Eng J Med 2013;369(11):1023-1034 38
The open issue: BRAF testing in daily clinical practice 15/06/2015 39
Acquired resistance to anti-egfrs Acquired resistance Drug Response 15/06/2015 40
A new perspective: Liquid biopsy 15/06/2015 41 Crowley E et al. Nat Rev Clin Oncol 2013;10(8):472-484; From Bettegowda C et al. Sci Transl Med 2014;6(224):224ra24. Reprinted with permission from AAAS
Acquired resistance: a common experience 15/06/2015 42 Diaz LA Jr and Bardelli A. J Clin Oncol 2014;32(6):579-586. Reprinted with permission. (2014) American Society of Clinical Oncology. All rights reserved
Acquired resistance: what really happens The continuous monitoring of circulating cell-free DNA shows the emergence of mutations in RAS pathway as a potential mechanism of acquired resistance to anti-egfrs. 15/06/2015 43 Reprinted by permission from Macmillan Publishers Ltd: Misale S et al. Nature 2013;486(7404):532-536 2013; From Bettegowda C et al. Sci Transl Med 2014;6(224):224ra24. Reprinted with permission from AAAS
Conclusions - 1 RAS testing is mandatory in patients candidate to anti-egfr therapy. An extended molecular selection, including KRAS and NRAS (exon 2-3-4) mutational status, allows to identify: a population of patients (RAS mut) that do not benefit from the anti- EGFR and may even derive a detrimental effect; a population of patients (RAS wt) in which the benefit from anti-egfr is significantly amplified. 15/06/2015 44
Conclusions - 2 Also BRAF testing may be useful in clinical choices: The impact of anti-egfrs is minimal if not absent in BRAF mutant patients. An intensive treatment might be a promising strategy to contrast the aggressiveness of BRAF mutant disease (FOLFOXIRI plus Bev may be a valid option). BRAF is a compelling druggable target. Waiting for data from new therapeutic strategies (i.e. BRAFi±MEKi±anti-EGFR). Liquid biopsies may be a new reliable tool to track the dynamism of tumour progression and to clarify mechanisms of acquired resistance. 15/06/2015 45
Thank you! 15/06/2015 46