Oncolytic Virotherapy Summit Novel stroma targeted and microenvironment-inducible oncolytic adenoviruses (OAVs)

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1 Oncolytic Virotherapy Summit 2016 Novel stroma targeted and microenvironment-inducible oncolytic adenoviruses (OAVs) Osvaldo L. Podhajcer, Ph.D. Superior Researcher CONICET (Consejo Nacional de Investigaciones Cientificas y Tecnologicas) Head Laboratory of Molecular and Cellular Therapy Instituto Leloir

2 Cancer Facts Worldwide more than 1 million women are diagnosed with a gynecologic cancer Melanoma is the third most common cancer among women ages and the second most common cancer in men ages Worldwide, more than 200,000 people die annually of pancreatic cancer, making it the fourth leading cause of cancer-related death in the United States

3 Current Immunotherapy approaches Dendritic Cells loaded with TAA (CAR)-T cells: mainly for ALL, CLL and non-hodgkin Lymphoma using CD19 as a target. Targeted Antibodies Cetuximab/Rituximab/Trastuzumab/others. Immunological check points inhibitors anti-cla4 /PD1. Oncolytic immunotherapy is based on the initial attack of the tumor mass by an armed oncolytic virus, followed by a secondary immune response exacerbated by a gene expressed by the virus

4 Why Adenovirus Lytic capacity, No biosafety concern Structure can be engineered for targeted therapy Knob Shaft Viral replication to occur specifically in malignant cells, avoiding replication in normal non-targeted cells

5 CROSS TALK BETWEEN MALIGNANT AND STROMAL CELLS ENABLES METASTATIC DISSEMINATION Stromal soluble factors Fibroblasts Malignant cells Endothelial vessels Each individual primary tumor has the potential to be classified into a poor prognostic mesenchymal subtype if the tissue employed in the analysis contains CAFs

6 Aspects to consider when engineering a virus for targeted therapy Targeting Malignant and Stromal Cells Attenuating lytic effect in normal cells Use of Hybrid TSP Promoters Use of Fiber Chimerism

7 The Road Map of UIO-512 Tumor Promoter Selection to drive E1A expression Insulator Incorporation Arming the virus Incorporation of hipoxia and inflammation DNA-responsive motifs Fibre exchange E1A mutation to restrict prb binding GMCSF cloning Hexón Exchange

8 Selection of a Tumor Specific Promoter active in malignant and stromal cells SPARC is overexpressed in malignant and cancer associated stromal cells in human melanomas

9 SPARC is overexpressed in malignant and cancer associated stromal cells in ovary cancer SPARC is expressed by CAF and endothelial cells in ovary cancer Sparc promoter is methylated in 68% of primary ovarian tumors

10 TSP F512, the Insulator and the TK gene AdF512 virus (a former version of UIO512) was able to inhibit human melanomas established in nude mice Tumor volume mm 3 A Ad-F512 0 SB2 Ad-β-gal (n=4) Ad-F512 (n=5) Days after adenovirus injection Percent survival Ad-b- gal Ad-F512 (P=0.0483) Days after adenovirus injection B MiaPaCa pancreatic tumors Ad-b-gal Ad-F512

11 A UIO512 former version was able to infect and express reporter genes not only in malignant cells but also in endothelial and fibroblastic cells inside the tumor mass

12 The Road Map of UIO-512 Tumor Promoter Selection to drive E1A expression Insulator Incorporation Arming the virus Incorporation of hipoxia and inflammation DNA-responsive motifs Fibre exchange E1A mutation to restrict prb binding GMCSF cloning Hexón Exchange

13 Lytic Activity of UIO512 whose replication is driven by a triple Chimeric Promoter Fetal Fibroblasts WI38

14 The Road Map of UIO-512 Tumor Promoter Selection to drive E1A expression Insulator Incorporation Arming the virus Incorporation of hipoxia and inflammation DNA-responsive motifs Fibre exchange E1A mutation to restrict prb binding GMCSF cloning Hexón Exchange

15 In vivo lytic activity: Combining a triple chimeric Promoter and a chimeric fiber

16 The Road Map of UIO-512 Tumor Promoter Selection to drive E1A expression Insulator Incorporation Arming the virus Incorporation of hipoxia and inflammation DNA-responsive motifs Fibre exchange E1A mutation to restrict prb binding GMCSF cloning Hexón Exchange

17 E1A binds prb, Releases E2F and Cells can Cycle p300 prb E1A

18 Fresh explants obtained from ovary cancer and normal samples Viral Replication was assessed using E4 gene copies as a surrogate marker UIO-512 effectively and selectively replicates in fresh samples of primary ovary cancer and not in normal ovary

19 UIO-512(v1) replicates in fresh samples obtained from ovary cancer refractory to chemotherapy Patient 15 Patient 16 Relative E4 Copy number / ng of DNA Ovary tumor Spleen Met Intestine Met-1 * * * * Intestine Met Hours after virus infection Relative E4 Copy number / ng of DNA 10 4 Left Ovary Tumor Right Ovary Tumor Liver Met * ** * * Hours after virus infection Ad-wt 5/3 AdF512v1

20 Day -7 Day -1 Day 0 Day 2 Day 4 Day 6 Day 9 Day 23 Day 30 UIO-512 was able to inhibit almost completely peritoneal carcinomatosis from human ovary cancer in nude mice A Tumor I.P AdOv CRAd I.P Sacrifice B Photons/s AdOv PBS (p=0.0038) ** Days after adenovirus injection

21 Infection of stromal cells with a previous version of UIO512 led to significant reduction in the amount of SKOV3-luc cells. Stromal cells supported viral replication and spreading leading the elimination of co-plated ovary cancer cells A previous version of UIO512 replicates in tumor xenografts composed of malignant cells and even better in tumors made by a mix of malignant and stromal cells

22 The Road Map of UIO-512 Tumor Promoter Selection to drive E1A expression Insulator Incorporation Arming the virus Incorporation of hipoxia and inflammation DNA-responsive motifs Fibre exchange E1A mutation to restrict prb binding GMCSF cloning Hexón Exchange

23 UIO-512: A smart adenovirus UIO-512 is Designed to Specifically Attack the Malignant Cells AND the Tumor Stroma, sense the tumor microenvironment and unleash an immune attack UIO-512 NFkB element responsive to inflammation HRE element responsive to hypoxia Viral E1A gene deleted in prb binding site Immunostimulatory gene Hybrid fiber Viral backbone DO 490 nm SKOV3 N 21-2 SKOV3 N+TNFa 21-2 SKOV3 H 21-2 SKOV3 H+TNFa MOI

24 Adenovirus exhibit natural tropism for liver and spleen through a bridge provided by coagulation factos FX 9 and 10 that bind to HVR7 in HEXON Alba et al, Blood 2010

25 The Road Map of UIO-512 Tumor Promoter Selection to drive E1A expression Insulator Incorporation Arming the virus Incorporation of hipoxia and inflammation DNA-responsive motifs Fibre exchange E1A mutation to restrict prb binding GMCSF cloning Hexon Exchange

26 HVR7 corresponding to serotype 5 is being modified through alternative approaches AdHEX5-3 AdHEX5-43 AdHEX35

27 UIO also replicates in fresh Cervical Cancer Explants UIO512 also replicates in fresh Uterine Cancer Explants

28 UIO-512 replicates in A549 lung adenocarcinoma cells and tumors e4 gene copies /ng tdna e4 gene copies /ng tdna MOI hours post infection

29 UIO512 replicates in human and murine colorectal cancer cells Percent survival LoVo N LoVo N+TNFa LoVo H LoVo H+TNFa Percent survival HT29 N HT29 N+TNFa HT29 H HT29 H+TNFa MOI MOI Percent survival CT26 cells UOI512 N N +TNFα H H +TNFα MOI

30 Reaching a Clinical Trial

31 Oncolytic Immunotherapy Verónica Lopez: Melanoma and ovary cancer Ana Alfano Oncolytic Immunotherapy Eduardo Cafferata: Gastrointestinal cancer Agostina Russo, Elvia Rivas Supported by National Agency for Promotion of Science and Technology (Foncyt/Fonarsec), Argentina Instituto Nacional del Cancer (Argentina) Friends of Instituto Leloir for the War on Cancer (AFULIC, Argentina) CONICET, Argentina