Overcoming Treatment Challenges in Sarcomas: Promising Novel Targeted Agents George D. Demetri, MD Center for Sarcoma and Bone Oncology Dana-Farber Cancer Institute Ludwig Center at Dana-Farber / Harvard Boston, Massachusetts

Development of Molecularly Targeted Agents for Sarcomas A Model for Personalized Anticancer Drug Development

OFF Tumor Cell Growth Arrest and Cancer Regression ON Tumor Cell Survival and Growth Searching for Critical Switches in Sarcomas

Gain-of-Function Mutations of c-kit in Human Gastrointestinal Stromal Tumors Seiichi Hirota, Koji Isozaki, Yasuhiro Moriyama, Koji Hashimoto, Toshirou Nishida, Shingo Ishiguro, Kiyoshi Kawano, Masato Hanada, Akihiko Kurata, Masashi Takeda, Ghulam Muhammad Tunio, Yuji Matsuzawa, Yuzuru Kanakura, Yasuhisa Shinomura, Yukihiko Kitamura Finding the Critical Switch in the Gastrointestinal Sarcoma known as GIST Science 279: , 1998.

Imatinib is a Highly Effective Targeted Agent in GIST Baseline Pre- Imatinib ON 1 month on Imatinib OFF

Demetri GD, et al. Proc Am Soc Clin Oncol 2005; Abstract BaselineDay 7 PET Normal Heart and Kidneys PET after 7 days of Sunitinib Sunitinib is an Effective Targeted Agent for Imatinib-Resistant GIST

Targeting Pathogenic Pathways in Other Types of Sarcomas Besides GIST P P P P PDGFRA P P P P KIT PI3K AKT mTOR Raf Mek Ras Erk Nucleus Transcription factors Cell adhesion Cell survival Cell proliferation Apoptosis Cell differentiation Angiogenesis PKCtheta S6K

The Next Successful Application of Kinase Inhibition to Sarcoma Therapy Dermatofibrosarcoma Protuberans (DFSP) –Balanced translocation - t(17;22) - leads to uncontrolled production of PDGF ligand –This induces autocrine activation of the wild-type PDGF-receptor system –Imatinib and Sunitinib also block PDGF-receptors

After 5 months of Imatinib Complete Clinical Response sustained and ongoing > 5 years Inhibiting PDGF-R with Imatinib in Advanced Dermatofibrosarcoma Protuberans (DFSP)

DFSP: Response to Imatinib McArthur et al. J Clin Oncol 2005; 23:866. Decreased Cellularity Hyaline Change

Testing Kinase Inhibitors as Therapy for Other Sarcoma Subtypes Imatinib –Occasional activity in desmoid tumors (SARC) Sorafenib –Some activity in vascular sarcomas (MSKCC) Sunitinib –Some activity in vascular sarcomas and desmoplastic small round cell tumor (MSKCC and DFCI) Dasatinib – SARC trial ongoing

Testing Kinase Inhibitors as Therapy for Other Sarcoma Subtypes Pazopanib –Oral Tyrosine Kinase Inhibitor with activity against VEGF-R, PDGFR, and KIT, tested by EORTC –Activity demonstrated in several subtypes including leiomyosarcomas and synovial sarcoma –Phase III clinical trial to begin soon with EORTC and other international collaborations

Targeting Pathogenic Pathways in Other Sarcomas P P P P KIT P P P P PDGFRA PI3K AKT mTOR Raf Mek Ras Erk Nucleus Transcription factors Cell adhesion Cell survival Cell proliferation Apoptosis Cell differentiation Angiogenesis PKCtheta S6K mTOR

mTOR-driven Sarcomas LAM and PEComa family of tumors –Lymphangioleiomyomatosis (LAM) –Angiomyolipoma (AML) –Perivascular Epitheliod Cell-oma (PEComa) LAM/AML can be associated with Tuberous Sclerosis Complex or sporadic

Patient with Metastatic PEComa Responding to mTOR Inhibitor (Sirolimus) Wagner, Morgan, Antonescu et al

Deforolimus: a Novel mTOR Inhibitor l Non-prodrug rapamycin analog l Forms a tripartite complex with FKBP12 and mTOR l Inhibits mTOR activity at nM levels l Compatible with either i.v. or oral delivery Metcalf CA et al. Proc Am Assoc Cancer Res 2004; 45:2476. FKBP mTOR (FRB Domain )

18 May 2004 (Baseline) 08 Dec Sep 2004 Mita M, et al. Proc Eur J Cancer 2004; 40A, Abstract 409. Phase I Deforolimus Trial: Objective Response in Chemotherapy-resistant Ewing’s Sarcoma 20-year old patient with metastatic Ewing’s sarcoma progressing despite nine prior anti-cancer regimens Daily dosing with Deforolimus, 15 mg (IV)

Response to the mTOR Inhibitor Deforolimus in Chemotherapy-resistant Osteosarcoma PET Day 1 (Baseline) PET Day 53PET Day 5 Fused CT/PET Images Sankhala KK, et al. Proc Am Soc Clin Oncol 2005; 23: 823.

Monitoring Deforolimus Inhibition of mTOR Activity in Blood V. Rivera, et al. Deforolimus Study Group. Day 1-Pre Day 1-4 hr Day 2-Pre Target of mTOR Activity Total Target Hrs post-dose

Phase II Deforolimus Trial: Promising Progression-Free Survival (PFS) Sarcoma Subtype6-Month Rate Median (wks) Bone Sarcoma25%16 Soft-tissue Sarcomas 24%15 Leiomyosarcoma 22%16 Liposarcoma 30%16 Other soft-tissue sarcomas 23%15 Overall PFS 24%15 Benefits observed across all sarcoma subtypes

Historical Context for Promising Disease Control with Deforolimus in Sarcomas Progression-free Survival (PFS) Compared with Historical Data from EORTC Historical Data (EORTC) Deforolimus Inactive Agents Active Agents No. of Patients Median PFS15 wks7 wks8 wks 3-month PFS58%21%39% 6-month PFS24%8%14%

Phase II Activity of Deforolimus in Sarcomas Promising activity of Deforolimus in patients with a broad range of advanced soft-tissue and bone sarcomas –Achieved primary endpoint of ≥ 25% Clinical Benefit Response in each histologic subgroup of advanced sarcomas No significant differences among the 4 sub-groups –29% overall CBR rate despite low incidence of tumor shrinkage –PFS more than double that of historical control (EORTC) 24% 6-month PFS rate (vs. 8%) 15-week median PFS (vs. 7 weeks) Well-tolerated with manageable side-effects A solid foundation upon which a definitive phase III trial has been developed to test the activity of deforolimus

Phase III Trial (“SUCCEED”): Deforolimus vs. Placebo to Maintain Clinical Benefit from Prior Chemotherapy in Sarcomas Primary Endpoint Progression-Free Survival Secondary Endpoints Overall Survival Objective Response Rate Improvement in Symptoms Safety and Tolerability of Deforolimus Confirmed Favorable Outcome (PR, CR, SD) After Prior Chemotherapy (< 1 year on therapy) 1:1 Randomization Placebo (Oral)Deforolimus (Oral)

IGF1 and IGF1-R Signaling is a Promising Target for Sarcomas Nat Rev Cancer © 2004 Nature Publishing Group.

Anti-IGF1R Monoclonal Antibody R1507: Responses in Ewing Sarcomas- Phase I Clinical Study Patient 7002: 27-year-old male Ewing’s sarcoma with lung metastasis Partial Response (PR) after 25 weeks of R1507 Patient 8012: 28-year-old female Ewing’s sarcoma with lung metastasis PR after 6 weeks of R1507 Restaging Week 25 Dec 29, 2006 Baseline June 19, 2006 Restaging Week 6 Jan 25, 2007 Baseline Dec 8, 2006

Targeting Hsp 90 in Sarcomas Preferential targeting to cancer Cancer cell Hsp90 is different from Hsp90 in normal cells Specific chaperone function: stabilization of oncogenes in key cell signaling pathways

Wagner et al. ASCO Activity of Hsp90 Inhibitor IPI-504 in Metastatic Liposarcoma Baseline Cycle 9 Prior gemcitabine/vinorelbine (13% growth after 2 cycles)

Not all Molecular Targeted Agents are Rationally Designed – but the clinical evaluation can be rational and targeted Binds to DNA minor groove, bending the helix Interacts with transcription factors and other DNA binding proteins Major activity in myxoid/round cell liposarcoma with TLS/CHOP fusion oncoprotein (DNA binding protein) Sea Tunicate, Ecteinascidia Turbinata Ecteinascidin-743 (Trabectedin), a tetrahydroisoquinoline alkaloid (MW = 762)

p= HR: Trabectedin Improves Time to Progression in Advanced Histopathologically Confirmed Leiomyosarcomas and Liposarcomas (Independent Review)

Grosso, Jones, Demetri, et al, Lancet Oncology Efficacy of Trabectedin (ecteinascidin-743) in Advanced Pretreated Myxoid Liposarcomas: a Retrospective Study Trabectedin Induces Changes in Tumor Density Before Tumor Changes in Size 0 +1 c +5 c +8 c +11 c

Extrinsic and Intrinsic Apoptosis Pathways as Targets Adapted from Ashkenazi A. Nat Rev Can 2002;2:420–430. Intrinsic pathway Caspase 3, 6, 7 Apoptosis Pro-apoptotic ligand FADD FLIP DR5 DR4 Extrinsic pathway Procaspase 8, 10 p53 Caspase 9 Caspase 8, 10 p53 BAX, BAK Mitochondria SMAC/DIABL O Chemotherapy Radiotherapy DNA damage PUMA, NOXA APAF1 Cytochrome c DNA damage BID IAP BCL2, BCLX L, MCL1

Molecularly Targeted Agents for Sarcomas Summary Sarcomas represent a variety of clinicopathologic subtypes for discovery and development of rationally- designed drugs to target specific molecular pathways Inhibition of a single pathway (KIT signaling) has proven effective for GIST Inhibition of multiple pathways will likely provide the best results over time