Bench to Bedside Translation Patient Derived Xenograft (PDX) Models and Case Study S. S. Gail Eckhardt, M.D. University of Colorado Cancer Center September 2014

Schema: Patient Derived Xenograft Model (PDX) These are the logistical steps that need to be worked out: consenting patients and getting tumor from pathology in OR Note: Tumors are never grown on plastic

Response of Colorectal PDX to a Range of Targeted Agents

Drug A Drug A/2500 mm 3 scale Drug A/600 mm 3 scale Drug B/2500 mm 3 scale Individual Tumor Growth Curves Reveal Heterogeneity

Colorectal (CRC) PDX Preservation of histopathologic diversity Stromal evolution to mouse Julien S et al. Clin Cancer Res 2012;18: ALU probe in situ hybridization stromal cells negative at 8 th passage PDX (Similar to primary)

Circos plots for the 1° tumor, metastasis and xenograft genomes Ding L, et al Nature Vol 464 April 2010 PDX and metastasis look similar Met PDX

Sorafenib in RCC PDX: Efficacy Recapitulated in PDX Models Yuen JSP et al BJC :

Cetuximab (EGFR Ab) Treatment in Unselected Metastatic CRC Xenopatients: Prediction of KRAS Status Effect Bertotti A et al. Cancer Discovery 2011;1: ©2011 by American Association for Cancer Research WT KRAS PDX responded (regression) If this had been known prior to phase III development, literally thousands of patients could have avoided ineffective and toxic therapy

Using PDX to Develop Rational Combinations Case Study: MEK Combination in CRC

Synthetic Lethality: Functional Screen for Actionable Resistance Pathways Identifying genes which when suppressed potentiate cell death with Drug X

3/5 R CRC PDX had >50% increase in FZD2 (Wnt receptor) post-treatment with a MEK inhibitor PDX Models Enable Validation of Cell-Line Derived Hypotheses

Rational Combination: MEK inhibitor + Wnt inhibitor Tested in PDX model We were also able to test the robustness of the response and durability

Clinical Translation: NCI/CTEP Approved Trial Note: PDX will be utilized to determine which are the most effective biomarkers to assess in patient’s tumors on the study

Three Dose Levels

Treatment Plan (dose escalation) In Cycle 1 (dose-escalation) – AZD6244 alone on Day -7 plasma sampling at baseline, 0.5, 1, 2, 4, 8, and 24 hours – Cyclosporin A alone on Day -3, plasma sampling at baseline, 0.5, 1, 2, 4, 8, and 24 hours On Day 1 all patients will receive both AZD6244 and cyclosporin A with plasma sampling at baseline, 0.5, 1, 2, 4, 8, and 24 hours Cyclosporin A levels will be checked 6-8 days later and at least every other week while patients are taking cyclosporin A The dose of cyclosporin A will be adjusted accordingly for a goal of steady- state trough levels of 125 to 250 ng/mL

Treatment Plan (dose expansion) Total of 20 patients with CRC – all required to have a baseline tumor biopsy A cohort of seven patients will have a 7-day AZD6244 alone run-in – Biopsy before AZD6244 and after the 7-day run-in – Assessing up-regulation of resistance (Wnt) pathway(s) – Biopsy at the time of progression AZD6244 and Cyclosporin A will be given together on day 1 No PKs in the expansion cohort

This was the First activated Experimental Therapeutics – Clinical Trials Network (ET-CTN) (UM1) clinical trial!

PETT Lab Program for the Evaluation of Targeted Therapy (PETT) Lab S. Gail Eckhardt, M.D. Aik-Choon Tan, Ph.D. John Tentler, Ph.D. Todd Pitts, M.S. Steve Leong, M.D. Jiyhe Kim, Ph.D. Jennifer Diamond, M.D. Anastasia Ionkina Stacey Bagby, BA, AAS, CVT Peter Klauck Lindsey Davis, M.D. Chris Lieu, M.D. Kit Wong, M.D.