Filippo de Braud & Francesco AgustoniS.C. Oncologia Medica

Fondazione IRCCS Istituto Nazionale Tumori

Modena, 18-19/11/2011

Terapia antiangiogenica oltre i Terapia antiangiogenica oltre i farmaci anti-VEGFfarmaci anti-VEGF

1927: tumour environment influences vasculature

• Warren Lewis described the vasculature of spontaneously occurring rat tumours

– each tumour type has different vascular architecture

– the growth and morphology of tumour blood vessels are therefore influenced by the tumour environment

Lewis. Johns Hopkins Hospital Bulletin 1927

1939: tumour angiogenesis observed in vivo

• Gordon Ide and colleagues used a transparent chamber to observe growth of a transplanted tumour in the ear of a rabbit

– tumour growth is accompanied by extensive formation of new vessels

– if blood vessel growth does not occur, the tumour fails to grow

Ide, et al. Am J Roentgenol 1939

1989: one molecule, multiple rolesNapoleaone Ferrara et al.

• A diffusible, endothelial-specific mitogen is identified and named vascular endothelial growth factor (VEGF)1

• VEGF and VPF are cloned independently by separate groups2,3

– they turn out to be the same molecule

1. Ferrara N, et al. Biochem Biophys Res Comm 19892. Leung DW, et al. Science 1989; 3. Keck PJ, et al. Science 1989

Angiogenesis is a balance between…

ANTI-ANGIOGENIC FACTORSAngiostatinEndostatinThrombospondin-1Angiopoietin-2IFN-αIL-2

PRO-ANGIOGENIC FACTORS VEGFFGFPDGFEGFTGF-αTGF-βIL-8LeptinAngiogenin

TARGET THERAPIESTARGET THERAPIES

Why targeting tumor vasculature?

• Tumors secrete angiogenic factors (1979, J. Folkman)

• Tumor neo-angiogenesis and vascular integrity is essential for tumor growth

• The cellular and stromal components of the tumor’s new and established vessels are a target for cancer therapy

Variety of approaches to targeting VEGF and the VEGFR system

Approach Effect

Anti-VEGF antibodies1 Bind and neutralise free VEGF

Anti-VEGFR antibodies1 Block VEGF from binding to its receptors

Small molecule TKIs1 Act directly on VEGFR tyrosine kinase to block VEGFR signalling

Soluble VEGFR1 Bind and neutralise free VEGF

Ribozymes2 Cleave VEGFR mRNA

Oligonucleotide aptamers3 Prevent synthesis of VEGF

1. Ellis, Hicklin. Nat Rev 20082. Schenone, et al. Curr Med Chem 20073. Taylor, et al. Biochem Biophys Res Commun 2008

Tumour characteristics and environment promote VEGF expression

EGF

IGF-1 PDGF

IL-8

bFGF

Hypoxia COX-2

NO Oncogenes

VEGF releaseBinding and activation

of VEGFR

H2O2

ProliferationSurvival Migration

Permeability

Increased expression(MMP, tPA, uPA, uPAr,

eNOS, etc.)

–P–P

P– P–

Adapted from Ferrara et al. Oncologist 2004 and Ferrara et al. Nature Med 2003

Regulation of VEGF in tumor cells

Oncogenes /Tumor Suppressor Genes

• Ras • Src• PTEN• p53• HER-2 • c-Jun

Activated Signaling Pathways/ Transcription Factors

• Src • COX-2• Bcl-2• AKT/PKB• AP-1• SP-1• NF-kB• HIF

Enviromental Factors, Growth Factors, Cytokines and their Receptors

• Hypoxia• Low pH• IL-1β• EGFR• IL-6• C-MET• PDGFR

Signaling Pathways Activated by VEGF

VEGF-targeted therapies

VEGF-antibodies

Bevacizumab

VEGF-Trap (Aflibercept)

VEGFR-TKI

SorafenibTelatenib Regorafenib

SunitinibSU14813

Pazopanib

Valatinib (ZD

ZD6474 (Vandetanib)

AG-013736 (Axitinib)

AMG 706

1997: humanisation of A4.6.1 produces bevacizumab

• Recombinant humanised monoclonal anti-VEGF antibody developed from murine anti-VEGF MAb A4.6.11

• 93% human, 7% murine

• recognises all major isoforms of human VEGF, Kd = 8 x 10–

10M

• terminal half-life 17–21 days

1. Presta, et al. Cancer Res 1997

Bevacizumab MoA: early and continued benefits

EARLY EFFECTS CONTINUED EFFECTS

1 Regression Normalisation2 Inhibition3

Decreases tumour size Improves delivery

of chemotherapy

Suppresses new vessel growth

Enables metastectomyIncreases PFSIncreases OS

Suppresses regrowth via vessel ‘scaffolds’

Willett, et al. Nat Med 2004; Gerber, Ferrara. Cancer Res 2005

= VEGF-Trap

VEGF-Trap

• VEGF-Trap is a fusion protein, made from key domains from VEGFR1 and VEGFR2 and from the FC fragment of human IgG1

• It only includes human aminoacid sequences• High affinity block on all VEGF-A isoforms

as well as the placental growth factor (PIGF)• Smaller size than monoclonal antibody (MW

115.000)• Long elimination half-life in men (20 days)

TKI antiangiogenic drugs

Targeting Angiogenesis: Multiple Tyrosine Kinase Inhibition

• Multitargeted agents have demonstrated higher response rates than single target agents

• Targeting a single receptor or enzyme may not sustain an antitumor response

• Targeting multiple receptors or enzymes can be achieved with:

– A combination of agents

– A single agent with specificity for multiple receptors or steps in tumor signaling pathways

• A single, multitargeted agent has several potential advantages:

– Reduced toxicity

– Simplified dosing

– Flexibility to administer with other treatment regimens

– Increased convenience and patient compliance

Activity spectrum of TKI

VEGFRVEGFR PDGFRPDGFR C-KitC-Kit CSF-CSF-1R1R

Ftl 3Ftl 3 FGFRFGFR

SU-11248SU-11248

SU-14813SU-14813

SORAFENIBSORAFENIB

PAZOPANIBPAZOPANIB

Effect of TKI on cellular kinases

Pazopanib

Sunitinib Simultaneously Inhibits RTKs on Tumor Cells, Pericytes and Endothelial Cells

Antiangiogenic effects Antitumor effects

PDGFR

PDGF

PERICYTE VASCULARENDOTHELIAL CELL

TUMOR CELL

VEGF

VEGFVEGF

VEGFR-1VEGFR-2 VEGFR-3 KIT PDGFRs

Cross-talk

RTKs expressed by tumor cells

Sunitinib Sunitinib Sunitinib Sunitinib

Sorafenib targets both tumor cells proliferation and tumor angiogenesis

Sorafenib inhibits proliferation and survival in tumor cells

Sorafenib inhibits proliferationand/or survival in endothelial cells

Tumor cellEndothelial cell

25

Sorafenib targets tumors at several molecular levels

Sorafenib: potent inhibitor of Raf kinase

• ~70% of melanomas contain B-Raf mutations

• Overall 30% of cancers display Ras mutations

• Preclinical activity in tumors exhibiting Ras mutations

Sorafenib: potent inhibitor of VEGFR-2• VEGFs probably important in pathogenesis

and prognosis of MBC• Potential use in multiple cancer types

through inhibition of angiogenesis

Additional activities against other proto-oncogenic proteins (VEGFR3, PDGFRb,-p38)

Potential use in large spectrum of cancers

Cell Cell proliferation

Growth factor

Tyrosine kinase

receptor

PSH3

SH3Tyr SH2 SOS

Ras-GDP Ras-GTP

Raf

Raf

MEK MEK

ERK ERK

P

P

P

Transcription elk-l

RKI

Successfull com

pleted phase III trials with

anti-VE

GF

pathways agents

Unsuccessfull or term

inated phase III trials w

ith anti-VE

GF

pathways agents

VEGF pathway-targeted drugs currently in neoadjuvant clinical trials

BMDCs

CAFsSDF1

Bone marrow derived cells (i.e myeloid suppressive cells) Cancer associated fibroblastsAdapted from Casanovas O Cancer Cell 2005

Osteopontin

Potential mechanisms of resistance to VEGF inhibitors

MMP9

1Oromi A et al Cell 2005 3Du R Cancer Cell 20082Ebos JM et al PNAS 2007

PDGF

SDF1

FGF/FGFR network

Characteristics:

• 18 ligands

• 4 TKI receptors: FGFR1, FGFR2, FGFR3, FGFR4

• One non-TKI receptor: FGFRL1

• Regulatory activity of cell proliferation, survival, migration and angiogenesis

Mechanisms of pathogenic cancer cell FGF signalling

Anti FGFR/FGFs Monoclonal Antibodies

Agent Company Target Clinical Development

FP-1039 Five Prime Therapeutics FGF ligand trap Phase I

Masitinib AB Science FGFR3, c-kit, PDGFR, FAK

Phase III (pancreas, GIST, multiple myeloma)

IMC-A1 InClone FGFR1-IIIc Preclinic

PRO-001 ProChon Biotech FGFR3 Preclinic

R3Mab Genentech FGFR3 Preclinic

1A6 Genentech FGF19 Preclinic

FGFR TKIAgent Company Target Clinical Development

Brivanib alaninate BMS VEGFR 1-2-3 FGFR 1-2-3

Phase III

Masitinib AB Science FGFR3, c-kit, PDGFR, FAK

Phase III (pancreas, GIST, multiple myeloma)

BIBIF1120 Boehringer Ingelheim

VEGFR 1-2-3FGFR 1-2-3PDGFR a & B

Phase III

TKI258 (Dovitinib) Novartis VEGFR 1-2-3, FLT, FGFR 3cKit , PDGFR B

Phase II

TSU-68 Taiho Pharm. VEGFR1, FGFR 1PDGFR B

Phase I/II

E-3810 EOS VEGFR ; FGFR1 Phase I

E7080 Eisai FGFR, PDGFR, VEGFR Phase I

ALK-1: Biology and Signaling In Angiogenesis• ALK-1 (activin receptor like kinase I) is a

TGFβ receptor mostly restricted to endothelial cells in adults

• 2 known ligands

• TGFb-1, 3 (low affinity)

• BMP-9 and BMP-10 (high affinity)

• ALK-1 is required for vascular development, and its loss of function is linked to hereditary hemorrhagic telangectasia (HHT-2) in humans, which is associated with increased ALK-1 expression, plasma VEGF and TGFb

• Hypothesis in cancer: ALK-1 is pro-angiogenic by contributing to vascular maturation/stabilization

• PF-03446962 is a fully human IgG2 mAb that inhibits ALK-1

Different Vessel Phenotype Between Anti-ALK-1 and Anti-VEGF• Human foreskin/SCID mice chimera model implanted with human melanoma• Human CD31 (EC) co-staining with desmin (perivascular and smooth muscle cells)

Control

Endothelial cells

SMCs and PCs

Anti-ALK1Bevacizumab

Combination

Combo

Control

(No D

ose)

Bevac

izum

ab

(5 m

g/kg,

Q5D

)Ant

i-huA

LK1

(10

mg/

kg, Q

W)

Combi

natio

n0.00.20.40.60.81.01.21.41.61.8

**

Tu

mo

r W

eig

ht

(g)

Key Preclinical Data• Proangiogenic factors (VEGF and/or bFGF) are required for

ALK-1 to sustain tumor vessel growth • In vitro, the proliferation of endothelial cells resistant to VEGFR

TKI (sunitinib) was significantly reduced after PF-03446962 administration

• In tumors resistant to VEGFR TKI – ALK-1 gene was upregulated; VEGFR-2 was downregulated – ALK-1 protein was localized within the mature vasculature of

the tumor– Resistant tumors responded to single agent anti–ALK-1 better

than VEGFR TKI-sensitive tumors

The vascular phenotype after ALK-1 blockade is different than anti-VEGF, confirming a different and potentially complementary

mechanism of action

Filippo de Braud & Francesco AgustoniS.C. Oncologia Medica

Fondazione IRCCS Istituto Nazionale Tumori

Modena, 18-19/11/2011

Thanks…

CLINICAL OUTCOMESCLINICAL OUTCOMES

Breast Cancer

– Bevacizumab in LR/mBC

Overview of three randomised phase III trials

– E2100 (bevacizumab combined with weekly paclitaxel)

Trial design, patient population, efficacy, safety, summary

– AVADO (bevacizumab combined with 3-weekly docetaxel)

Trial design, patient population, efficacy, safety, summary

– RIBBON-1 (bevacizumab combined with either taxane/anthracycline or capecitabine)

Trial design, patient population, efficacy (capecitabine cohort), efficacy (taxane/anthracycline cohort), safety, summary

Bevacizumab as first-line

44

RIBBON-13

E21001 AVADO2 XelodaTaxane/

anthracycline

Placebo controlled

No Yes Yes

ChemotherapyWeekly

paclitaxel3-weekly docetaxel

Xeloda

3-weekly docetaxel/nab-

paclitaxel or AC/FAC/EC/FEC

Bevacizumab dose

10 mg/kg q2w

7.5 or 15 mg/kg q3w

15 mg/kg q3w

Primary endpoint

PFS (inv) PFS (inv) PFS (inv)

IRF review Retrospective No Prospective

1Miller et al. NEJM 2007; 2Miles et al. ASCO 2008; 3Robert et al. ASCO 2009

45

Three Randomised Trials of First-Line Bevacizumab-Based Therapy in LR/mBC: Similar Trial Designs

RIBBON-14

E21001,2a AVADO3b XelodaTaxane/

anthracycline

Pacl Avastin + pacl

Placebo + doce

Avastinc

+ docePlacebo + Xeloda

Avastin + Xeloda

Placebo + t/a

Avastin + t/a

ORR, % 22 50 46 64 24 35 38 51

p<0.0001 p=0.0003 p=0.0097 p=0.0054

Median PFS, months

5.8 11.3 8.1 10.0 5.7 8.6 8.0 9.2

HR 0.48

p<0.0001

0.67

p=0.0002d

0.69

p=0.0002

0.64

p<0.0001

aIRF assessment; bPFS censored for non-protocol therapy before disease progression; c15 mg/kg q3w; dExploratory p value

1Klencke et al. ASCO 2008; 2Gray et al. JCO 2009; 3Avastin SmPC 2009; 4Robert et al. ASCO 2009

Consistent Benefit with Bevacizumab-Based Therapy: Significant Improvement in PFS & ORR

RIBBON-14

E21001 AVADO2,3 XelodaTaxane/

anthracycline

Pacl Avastin pacl

Placebo + doce

Avastina

+ docePlacebo + Xeloda

Avastin + Xeloda

Placebo + t/a

Avastin + t/a

Median OS, months

24.8 26.5 31.9 30.2 21.2 29.0 23.8 25.2

HR 0.87

p=0.14

1.03

p=0.85

0.85

p=0.27

1.03

p=0.83

1-year OS rate, %b

74 81 76 84 74 81 83 81

p=0.017 p=0.02 p=0.076 p=0.44

a15 mg/kg q3w; bExploratory p value1Cameron EJC Suppl 2008; 2Avastin SmPC 2009; 3Roche data on file 2009; 4Robert et al. ASCO 2009

Secondary Endpoint: Overall Survival

RIBBON-2: Study Design

Primary endpoint: investigator-assessed PFS pooled across the chemotherapy cohorts

Treatment◦ taxane (paclitaxel 90mg/m2/wk for 3 of 4 wk; paclitaxel 175mg/m2, nab-paclitaxel 260mg/m2, or docetaxel 75–100mg/m2 q3w)

◦ gemcitabine (1,250mg/m2 on days 1 and 8 q3w)

◦ capecitabine (2,000mg/m2 days 1–14 q3w)

◦ vinorelbine (30mg/m2/wk)

◦ Bevacizumab or placebo (15mg/kg q3w or 10mg/kg q2w, depending on chemotherapy regimen)

CHOICE OF CHEMOTHERAPY

BY INVESTIGATOR

Previously treatedmBC (n=684)

Stratification factors:

• Investigator choice ofchemotherapy on study

• Interval from mBCdiagnosis to first PD

• ER and PR status

Taxaneor

Gemcitabineor

Capecitabineor

Vinorelbine

Chemotherapy+ Bevacizumab

Chemotherapy+ placebo

Treat untilPD

RA

ND

OM

ISE

2

:1

Brufsky, et al. SABCS 2009

RIBBON-2: Bevacizumab Significantly Improves PFS in Second-line mBC

Brufsky, et al. SABCS 2009

Median PFS, 7.2 vs. 5.1 monthsHR=0.78, p = 0.0072

1.0

0.8

0.6

0.4

0.2

00 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34

Duration of PFS

225 165 129 93 77 44 33 19 12 8 5 4 3 1 1 0 0 0459 381 334 254 190 130 87 47 27 18 9 5 2 1 1 0 0 0

Number at risk:Chemo/PlaceboChemo/Bev

Pro

port

ion

of p

rogr

essi

on-f

ree

Chemo/Placebo (n=225)Chemo/Bev (n=495)

Phase II Trial of Sunitinib in Patients with Previously-Treated

Metastatic Breast Cancer

Kathy D. Miller, MD

American Society of Clinical Oncology (ASCO)

42nd Annual Meeting 2005 May 13–17, Orlando, FL

Single-agent Sunitinib Showed Activity in this Heavily Pretreated, Diverse

Population

Best response, n (%)

Number of patients

(N=64*; %)

Partial response 7 (11)

Stable disease ≥22 weeks 5 (8)

Clinical benefit† 12 (19)

Progressive disease or stable disease ≤22 weeks

41 (64)

*Data for 11 patients (17%) were missing or not evaluable†Partial response or stable disease ≥22 weeksMiller et al. ASCO 2005 (Abstract 563, oral presentation)

Pfizer Inc., data on file

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