Personalized Therapy in Colorectal Cancers

1. Personalized Therapy in Colorectal Cancers J. Randolph Hecht, MD Professor of Clinical Medicine Director, UCLA GI Oncology Program David Geffen School of Medicine at UCLA

2. What Does Personalized Therapy Mean? • Right Treatment • Right Patients

3. Biomarker • NIH Definition: a characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. • Predictive: (Ex: HER-2, BRAF, cytogentic abnormalities) • Prognostic: (Ex: HER-2, KRAS)

4. Biomarkers

5. Evaluating Predictive Biomarkers: Trial Design Receive treatment Biomarker positive Do not receive treatment R Patient Population Receive treatment Biomarker negative Do not receive treatment

6. Biology of Colorectal Cancers Subgroup Analysis Breast cancer does it, is it time for CRC? CIN vs MSI vs CIMP+ CIN: Majority of tumors MSS, APC mutation MSI: Abnormal DNA mismatch repair ~15% Most Sporadic (BRAF mut); others HNPCC Molecular Subgroup Analysis

7. Tabernero, ASCO GI 2013

8. Uronis, ASCO GI 2013

9. Cancer Genome Atlas Network, Nature 2012

10. Biomarkers • Histology: TNM Dukes, J Path Bacteriol, 1932

11. Survival Rates of by Stage of Adenocarcinoma of the Colon 100 90 80 70 60 Survival Rate 50 40 30 20 10 0 0 2 3 4 5 1 IIIAIIBIICIIIAIIIBIIICIV 100100100100100100100100 91.489.985.466.098.383.471.939.9 87.083.477.852.588.070.850.319.7 82.677.869.145.383.659.339.011.3 78.272.062.941.579.151.732.97.6 74.066.558.637.373.146.328.05.7 Yrs From Diagnosis Edge SB, et al. AJCC cancer staging manual. 2010. Data from the SEER 1973-2005 Public Use File diagnosed in years 1998-2000.

12. Other Putative Biomarkers: Molecular pathology CTCs Molecular abnormalities Mutations microRNAs Gene expression profiles

13. Where Would Biomarkers Be Most Useful? Adjuvant Treat those who would benefit Don’t treat those that won’t Metastatic Disease We have multiple agents. How can we choose for safety and efficacy?

14. Stage II Colon Cancer • Which stage II colon cancer patients should be treated with adjuvant chemotherapy? • 75% to 80% cured with surgery alone • Benefit of chemotherapy is small and no consensus on whom to treat or on how to identify whom to treat • Decision to give chemotherapy based on • Clinical/pathologic markers of risk • Molecular biomarkers • Not informative for majority of patients

15. Adjuvant Therapy Increases OS:ACCENT Database of 20,898 Patients Stage II Stage III ∆ = 5.4%P = .026 1.0 0.8 0.6 0.4 0.2 0 1.0 0.8 0.6 0.4 0.2 0 ∆ = 10.3%P < .0001 Probability of Survival Probability of Survival Surgery alone: 66.8% Surgery alone: 42.7% Surgery + FU-based chemotherapy: 72.2% Surgery + FU-based chemotherapy: 53.0% 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 Follow-up (Yrs) Sargent D, et al. J Clin Oncol. 2009;27:872-877.

16. Determining Who Benefits From Adjuvant Therapy in CRC 1.André T, et al. J Clin Oncol. 2009;27:3109-3116. 2. Hutchins G, et al. J Clin Oncol. 2011;29:1261-1270. 3. Sargent DJ, et al. J Clin Oncol. 2010;28:3219-3226. 4. Sinicrope FA, et al. J Natl Cancer Inst. 2011;103:863-875. 5. Ribic CM, et al. N Engl J Med. 2003;349:247-257. • Risk assessment in stage II (III) CRC: prognostic factor(s) of recurrence of disease and predictive factor(s) to the treatment. • High-risk prognostic factors[1] • Stage II: T4, tumor perforation, bowel obstruction, poorly differentiated tumor, venous invasion, or < 10 examined nodes • Stage III: age, lymph node involvement, T stage, tumor obstruction, differentiation • Defective mismatch repair and microsatellite instability[2-5]

17. MOSAIC: Exploratory Analysis of DFS and OS in “High-Risk” Stage II CRC Favors FOLFOX4 Favors LV5FU2 DFS at 5 Yrs Stage II High-risk stage II Stage III OS at 6 Yrs Stage II High-risk stage II Stage III 0.4 0.6 0.8 1.0 1.2 1.4 1.6 HR André T, et al. J Clin Oncol. 2009;27:3109-3116.

18. Missed Micrometastases LN “N0” H&E IHC+ RT-PCR+

19. MMR-D (MSI) Is a Favorable Prognostic Marker in Stage II (and III) Colon Cancer 1. Ribic CM, et al. N Engl J Med. 2003;349:247-257. 2. Roth AD, et al. J Clin Oncol. 2010;28:466-474. 3. Sargent DJ, et al. J Clin Oncol. 2010;28:3219-3226. 4. Gray R, et al. J Clin Oncol. 2011;29:4611-4619.

20. 5-FU Not Beneficial and Survival Longer in Stage II Patients With MMR Deficiency 100 80 No Adjuvant 5-FU Chemotherapy HR for OS: 0.47 (95% CI: 0.26-0.83;P = .004) 60 Percent Alive andProgression Free 40 HR: 0.51 (95% CI:0.29-0.89; P = .009) 20 MMR-d (n = 79)MMR-p (n = 436) 0 0 1 2 3 4 5 Yrs 100 80 HR for OS: 0.78 (95% CI: 0.49-1.24;P = .28) Adjuvant 5-FU Chemotherapy 60 Percent Alive andProgression Free 40 HR: 0.79 (95% CI:0.49-1.25; P = .30) 20 MMR-d (n = 86)MMR-p (n = 426) 0 0 1 2 3 4 5 Yrs Sargent DJ, et al. J Clin Oncol. 2010;28:3219-3226.

21. Genomic Tests for CRC Risk Stratification 35 35 Risk 30 30 95% CI 25 25 20 20 Risk of Recurrence at 5 Yrs (%) Risk of Recurrence at 3 Yrs (%) 15 15 10 10 5 5 P = .004 0 0 0 10 20 30 40 50 60 70 0 10 20 30 40 50 60 70 Colon Cancer Recurrence Score Recurrence Score • CALGB 9581: 13% (low risk) vs 21% (high risk) 5-yr recurrence in T3, MMR proficient disease[2] • QUASAR: 12% (low risk) vs 22% (high risk) 3-yr recurrence risk[1] Gene signatures provide prognostic, not predictive, information 12-gene recurrence score assay validated for recurrence risk in stage II patients 1. Gray RG, et al. J Clin Oncol. 2011;29:4611-4619. 2. Venook AP, et al. ASCO 2011. Abstract 3518.

22. Personalized Therapy For Metastatic Disease Cytotoxics Anti-EGFR Antibodies Anti-VEGF Pathway Agents

23. Cytotoxic Agents Fluoropyrimidines TS: A target. No clear evidence for choosing therapy DPD: Dihydropyrimidine dehydrogenase deficiency associated with severe FP toxicity Testing only in patients with toxicity Irinotecan UGT1A1*28 (10% of North Americans) Originally associated with diarrhea but later studies with neutropenia instead In package insert, but not used Topo 1: Conflicting data Oxaliplatin ERCC1: Unproven for efficacy

24. Anti-EGFR Agents

26. EGFR Signaling Pathway Ligand Extracellular EGFR Ras PI3K PTEN Raf Intracellular Akt MEK MAPK Cell survival Cell motility DNA Proliferation Metastasis Angiogenesis

28. KRAS as a Biomarker for Panitumumab Response in Metastatic CRC PFS log HR significantly different depending on KRAS status (p < .0001) Percentage decrease in target lesion greater in patients with wild-type KRAS receiving panitumumab Approved in EU in KRAS WT Patients With Wild-Type KRAS Patients With Mutant KRAS Pmab + BSC 1.0 Meanin Wks 1.0 Medianin Wks BSC alone Pmab + BSC Events/N (%) 0.9 Meanin Wks Medianin Wks 0.9 BSC alone Events/N (%) 0.8 19.0 12.3 0.8 115/124 (93) 9.3 7.3 0.7 114/119 (96) 9.9 7.4 76/84 (90) 0.7 Proportion With PFS 10.2 0.6 7.3 95/100 (95) 0.6 HR: 0.45 (95% CI: 0.34–0.59) 0.5 Proportion With PFS Stratified log rank test: P < .0001 0.5 HR: 0.99 (95% CI: 0.73–1.36) 0.4 0.4 0.3 0.3 0.2 0.2 0.1 0.1 0 0 40 44 40 44 6 8 10 12 14 16 18 22 24 26 28 30 34 36 38 42 46 48 50 52 6 8 10 12 14 16 18 22 24 26 28 30 34 36 38 42 46 48 50 0 2 4 20 32 2 4 20 32 52 0 Weeks Weeks Amado et al., JCO 2008.

29. What About G13D (~20% mutations) Tejpar et al., ASCO 2011

30. No Effect Of G13D in Larger Sample Peeters ASCO GI 2012

31. EGFR Signaling Pathway Ligand Extracellular EGFR Ras PI3K PTEN Raf Intracellular Akt MEK MAPK Cell survival Cell motility DNA Proliferation Metastasis Angiogenesis

32. BRAF • V600E mutation relatively common in CRC (5-15%) • Poor prognostic factor (Van Cutsem ASCO GI, 2010) • FOLFIRI+cetuximab PFS: 25.1 vs 14.1 months • Inhibitors: sorafenib, PLX4032 (vemurafenib) • PLX4032: 70% RR in V600E melanoma, but 5% in CRC

33. Pooled analysis of OS in patients withKRAS wt/BRAF mt tumors KRAS wt/BRAF mt HR [95% CI]: 0.633 [0.378–1.060] p=0.079 FOLFIRI / FOLFOX4 + cetuximab: (n=32) median 14.1 months FOLFIRI / FOLFOX4: (n=38) median 9.9 months KRAS wt/BRAF wt HR [95% CI]: 0.840 [0.710–0.993] p=0.041 FOLFIRI / FOLFOX4 + cetuximab: (n=349) median 24.8 months FOLFIRI / FOLFOX4: (n=381) median 21.1 months 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 0 6 12 18 24 30 36 42 48 54 60 Probability of overall survival Time (months) Number of patients CT+cetuximab 349 317 268 225 163 120 80 63 19 4 0 CT 381 350 283 212 149 107 63 46 17 2 0 CT +cetuximab 32 25 16 12 8 5 2 2 2 0 0 CT 38 24 14 6 6 3 3 1 0 0 0 Bokemeyer CI, confidence interval; CT, chemotherapy;HR, hazard ratio;mt, mutant;OS, overall survival; wt, wild-type

34. Other Markers (Unknown Benefit) Rare KRAS mutations NRAS Ligands (amphiregulin, epiregulin) Copy Number

35. Anti-VEGF Pathway Drugs None!

36. Molecular Profiling Multiple Targets (Caris, Foundation Medicine) Sequencing Explants No Evidence of Clinical Benefit Hours of Physician Time

37. We are on the verge of truly personalized therapy for colorectal cancer We need to be able to identify subgroups by genetic alterations and activated pathways We need to validate molecular tests before selling them to the public We need to identify new targets for new drugs We may have to find ways to do trials in small subsets

38. BONUS New indications for anti-VEGF pathway agents!!

39. Anti-VEGF antibodies (bevacizumab) Soluble VEGF receptors (VEGF-TRAP/ aflibercept) Anti-VEGFR antibodies (IMC-1121b) P P P P P P P P Agents Targeting the Vascular Endothelial Growth Factor (VEGF) Pathway VEGF VEGFR-1 VEGFR-2 Endothelial cell Small-moleculeVEGFR inhibitors (PTK787, sunitinib, sorafenib, regorafenib, axitinib)

40. Golden Age of CRC Therapeutics: Bevacizumab IFL/bevacizumab IFL/placebo 1.0 100 15.6 20.3 6.2 10.6 0.8 80 Progression-free Survival (%) Percent Surviving 0.6 (n = 402) 60 0.4 40 0.2 20 (n = 411) 0.0 0 0 10 20 30 40 0 10 20 30 Duration of Survival (months) Progression-Free Survival (months) HR = 0.66, P <.001 HR = 0.54, P <.001 Hurwitz H et al. N Engl J Med. 2004;350:2335-2342.

41. Bevacizumab Aflibercept Regorafenib What About Angiogenesis Inhibition After First Line Therapy?

42. E3200: Overall Survival 1.0 0.9 HR = 0.76 A vs B: p = 0.0018 B vs C: p = 0.95 0.8 0.7 0.6 P r o b a b i l i t y 0.5 No first line bev! 0.4 0.3 0.2 0.1 0.0 0 3 6 9 12 15 18 21 24 27 30 33 36 OS (months) TOTAL DEAD ALIVE MEDIAN A:FOLFOX4 + bevacizumab 289 246 43 12.9 B:FOLFOX4 290 257 33 10.8 C:bevacizumab 243 216 27 10.2 Giantonio BJ, et al. ASCO 2005

43. ML18147 (TML) study design Standard second-line CT (oxaliplatin or irinotecan-based) until PD BEV + standard first-line CT (either oxaliplatin oririnotecan-based)(n=820) PD Randomise 1:1 BEV (2.5 mg/kg/wk) + standard second-line CT (oxaliplatin or irinotecan-based) until PD CT switch: Oxaliplatin →Irinotecan Irinotecan→ Oxaliplatin Arnold 2012 Study conducted in 220 centres in Europe and Saudi Arabia

44. OS: ITT population 1.0 CT (n=410) BEV + CT (n=409) 0.8 Unstratifieda HR: 0.81 (95% CI: 0.69–0.94) p=0.0062 (log-rank test) 0.6 Stratifiedb HR: 0.83 (95% CI: 0.71–0.97) p=0.0211 (log-rank test) 0.4 OS estimate 0.2 0 9.8 mo 11.2 mo 0 6 12 18 24 30 36 42 48 Time (months) No. at risk CT 410 293 162 51 24 7 3 2 0 BEV + CT 409 328 188 64 29 13 4 1 0 aPrimary analysis method; bStratified by first-line CT (oxaliplatin-based, irinotecan-based), first-line PFS (≤9 months, >9 months), time from last dose of BEV (≤42 days, >42 days), ECOG performance status at baseline (0, ≥1)

45. PFS: ITT population 1.0 CT (n=410) BEV + CT (n=409) 0.8 Unstratifieda HR: 0.68 (95% CI: (0.59–0.78) p<0.0001 (log-rank test) 0.6 Stratifiedb HR: 0.67 (95% CI: 0.58–0.78) p<0.0001 (log-rank test) PFS estimate 0.4 0.2 0 4.1 mo 5.7 mo 0 6 12 18 24 30 36 42 Time (months) No. at risk CT 410 119 20 6 4 0 0 0 BEV + CT 409 189 45 12 5 2 2 0 aPrimary analysis method; bStratified by first-line CT (oxaliplatin-based, irinotecan-based), first-line PFS (≤9 months, >9 months), time from last dose of BEV (≤42 days, >42 days), ECOG performance status at baseline (0, ≥1)

46. What else does TML teach us? • Affirms the limited utility of Registry studies regarding interventions and outcomes: • BRITE: 9.5 v. 19.2 OS beyond PD • TML: 9.8 v. 11.2 BRiTE findings not replicated; the publication* could be cited as an example of the pitfalls of Registry data *Grothey et al, JCO, 2008 Venook 2012

47. Fully human fusion protein and soluble recombinant decoy VEGF receptor composed of Domain 2 of VEGFR1 and Domain 3 of VEGFR2 fused to the Fc of IgG1 Higher affinity for VEGF-A than bevacizumab and also blocks PlGF; T1/2 17 days EFC10262 (VELOUR ) Phase III Trial 2nd Line FOLFIRI +/- VEGF-TRAP (Aflibercept) Where has it been? Aflibercept (VEGF-TRAP)

48. VELOUR Study Design Aflibercept 4 mg/kg IV, day 1 + FOLFIRI q2 weeks R A N D O M I Z E 600 Metastatic Colorectal Cancer 1:1 Disease Progression Death • Stratification factors: • ECOG PS (0 vs 1 vs 2) • Prior bevacizumab (Y/N) Placebo IV, day 1 + FOLFIRI q2 weeks 600 Primary endpoint: overall survival Sample size: HR=0.8, 90% power, 2-sided type I error 0.05 Final analysis of OS: analyzed at 863rd death event using a 2-sided nominal significance level of 0.0466 (α spending function)

49. VELOUR: Results Van Cutsem, et al. WCGC 2011

50. VELOUR Study PFS OS • Overall results • Adding aflibercept to FOLFIRI in mCRC patients previously treated with an oxaliplatin-based regimen resulted in significant OS and PFS benefits Van Cutsem E et al. ESMO/WCGC 2011, Barcelona, Abstract O-0024.