Learning Objectives A t the conclusion of this presentation participants should understand the following:

2. Use of pharmacogenetics in understanding patient susceptibility to 5-FU toxicity Toxicity risks associated with variations in the genes DPYD and TYMS DPYD = DPD (Dihydropyrimidine Dehydrogenase) TYMS = TS (Thymidylate Synthase) Use of genetic test results in medical management Learning ObjectivesAt the conclusion of this presentation participants should understand the following:

3. Hereditary Cancer testing What is the likelihood that my patient will develop a future cancer? Example: Hereditary Breast and Ovarian Cancer Syndrome Tumor Characteristic testing Are there characteristics about this tumor that would dictate treatment options? Example: HER2/neu testing Pharmacogenetic testing Does my patient have something innate that will cause him/her to respond differently to treatment? Cancer Genetic Testing

4. The study of genetic variation that determines an individual’s response to drugs Pharmacogenetic testing can be beneficial in oncology because it can help determine How a patient will respond to chemotherapy Example: cytochrome P450 2D6 (CYP2D6) genotype and ability to metabolize tamoxifen The likelihood that a patient will experience severe side effects Example: TheraGuide® 5-FU Pharmacogenetics

5. 5-Fluorouracil metabolism 85% 15% Nature Reviews Cancer. 2003; 3:330-38.

6. DPD DeficiencyMechanism of Action • Variations in DPYD can lead to DPD insufficiency • This results in an inability to inactivate 5-FU leading to increased levels of active drug in the system that can result in greater toxicity

7. TS DeficiencyMechanism of Action • Variations in TYMS can lead to altered TS expression • Lower levels of the TS enzyme can lead to • Increased levels of active 5-FU • Toxicity

8. Is toxicity a significant clinical problem? Prevalence Rate: Grade 3-4 diarrhea JCO 1998 16: 3537-3541. Ann Oncol. 2002 Apr;13(4):566-75. JCO. 2006:24(25):4085-4091. JCO. 2007 25:102-109. JCO. 2008;26(13): 2130-2137.

9. Cassidy study: several patients discontinued treatment due to related side effects -6.7% of 5-FU patients Of patients who continued treatment following dose modification (reduced by 25-50%), several continued to have side effects 45/138 Hand Foot Syndrome 21/89 Diarrhea 6/30 Stomatitis Is toxicity a significant clinical problem? Ann Oncol. 2002 Apr;13(4):566-75.

10. FDA 2003 warning had been issued stating 5-FU is contraindicated in patients with a known DPD deficiency FDA WARNING FDA package warnings – http://www.fda.gov/medwatch/SAFETY/2003

11. 5-FU therapy candidates About 1 in 14 (7%) patients treated with 5-FU have Grade 3-4 toxicity associated with a DPYD or TYMS gene variation Who benefits from TheraGuide® 5-FU? Mol Cancer Ther 2006. 5(11): 289-291. J Clin Oncol. 2008;26(13):2130-2137.

12. What are the risks? • DPYD gene variations are associated with a 7-fold (or up to a 60%) risk of severe toxicity . Mol Cancer Ther 2006. 5(11): 289-291. PharmacogenomicsJ 2001.1(1): 65-70. JCO. 2008;26(13): 2130-2137.

13. What are the risks? • TYMS gene variations are associated with a 1.4 to 2.5-fold (or 22-52%) increased risk of severe toxicity PharmacogenomicsJ 2001.1(1): 65-70. Clin Cancer Res.. 2004 Sep 1;10(17):5880-8. Clin Cancer Res. 2006 Jul 1;12(13):3928-34. J Clin Oncol. 2008;26(13):2130-2137.

14. What is included in TheraGuide® 5-FU analysis? • The only clinical test that performs: • Full sequencing of the DPYD gene and • Analysis of the TYMS gene promoter region

15. DPYD (DPD deficiency) Three common variations account for the majority of known 5-FU toxicity to date IVS14+1 G>A, D949V, and I560S More than 40 different variations in DPYD have been identified as causing DPD deficiency Full sequencing is the “gold standard” for identifying mutations TheraGuide® 5-FUincludes full sequencing of DPYD Mol Cancer Ther 2006. 5(11): 289-291.

16. TYMS variations 2R/2R 2R/3R 3R/3R 4R variations have also been described The 2R/2R variation confers a 1.4-2.5-fold increased risk for adverse events TheraGuide® 5-FUincludes analysis of TYMS

17. As many as 1 in 4 individuals have a variation that increases the risk for5-FU related toxicity DPYD – 5% TYMS – 15-20% TheraGuide® 5-FU is used to determine a patient’s likelihood of 5-FU toxicity High Risk 7-fold (or up to 60%) risk for Grade 3 or Grade 4 toxicity Moderate Risk 1.4 to 2.5-fold (or 23-53%) risk for Grade 3 or Grade 4 toxicity Low Risk Common causes of 5FU toxicity is ruled out Indeterminate How are TheraGuide® 5-FU results reported? Mol Cancer Ther 2006. 5(11): 289-291. PharmacogenomicsJ 2001.1(1): 65-70.

18. Identifies patient risk for 5-FU toxicity Allows for personalized treatment options for cancer therapy More informed discussion regarding toxicity risk Enhanced patient monitoring Dose reduction considerations Alternate chemotherapies How are TheraGuide® 5-FU results used? Mol Cancer Ther 2006. 5(11): 289-291.PharmacogenomicsJ 2001.1(1): 65-70.Cancer Invest. 2006 Mar;24(2):215-7.Semin Oncol. 2007 Apr;34(2 Suppl 1):S37-40.Ann Oncol. 2005 Dec;16(12):1853-4.J. Clin. Onc. 1998 16: 3537-3541.Drugs. 2003.63(2):217-36.

19. TheraGuide® 5-FU can help predict a patient’s risk of toxicity to 5-FU Patient management can be personalized based on results Avoiding adverse events can help physicians save time, money, and improve patient quality of life In Summary

20. Supplemental Slides

21. National Cancer Institute Common Toxicity Criteria

22. National Cancer Institute Common Toxicity Criteria

23. 68 yo female Presented with recurrent breast cancer and lymphangitic lung disease after 3 years of being disease free TheraGuide® 5-FU was ordered due to the previous life threatening toxicity effectiveness of 5-FU in treating her cancer Patient was found to have a low risk result Proceeded with a 5-FU regimen Currently on treatment with marked improvement and has no 5-FU related toxicities Metastatic Breast Cancer PatientLow Risk Result