Istituto Superiore di SanitIstituto Superiore di Sanitàà III ConvegnoIII Convegno

PPREVENIRE LE COMPLICANZE DEL DIABETEREVENIRE LE COMPLICANZE DEL DIABETE DALLA RICERCA DALLA RICERCA DIDI

BASE ALLBASE ALL’’ASSISTENZAASSISTENZA

Roma, 16 febbraio 2009Roma, 16 febbraio 2009

Applicazioni cliniche della ricerca in retinopatia diabetica

Massimo PortaDipartimento di Medicina Interna

Università di Torino

FROM BENCH TO BEDSIDEFROM BENCH TO BEDSIDE

Ovvero …

la storia di quattro storie finite in modo inatteso e di una che non si sa ancora come finirà …

Storia Storia nn°°

1 1 --

SomatostatinaSomatostatina

GH/IGFGH/IGF--I Axis and DRI Axis and DR

1952: Sheehan syndrome (post-partum pituitary apoplexy) observed to revert PDR

1950-70: Pituitary ablation effective in arresting progression of PDR

1960-70: Growth hormone levels increased in diabetes

1980-90: Insulin-like growth factor-I (IGF-1) increased in vitreous of eyes with PDR

1980-90: Somatostatin may slow florid PDR1990- : Role of GH and IGF-1 in angiogenesis

IGFsIGFs in DRin DR

•

Elevated vitreous levels of IGF-I and -II found in patients with diabetic retinopathy1,2

•

IGF-I actions in the retina– Induce leakage across blood retinal barrier3

– Stimulate neovascularization4

– Stimulate contraction of Müller cells5

– Upregulate VEGF expression in retinal pigment epithelial cells

•

Inhibition of IGF-I receptor function inhibits neovascularization6

1. Grant et al. Diabetes. 1986;35:416.; 2. Burgos et al. Diabetes Care. 2000;23:80.3. Hussain et al. Diabetes. 1995;44:1209. ; 4. Castellon et al. Exp Eye Res. 2002;74;523.5. Guidry et al. Diabetes. 2004;53:2428.; 6. Smith et al. Nat Med. 1999;5:1390.

IGF-I concentrations in Vitreous (Grant et al., 1986)IGFIGF--I concentrations in Vitreous (Grant et al., 1986)I concentrations in Vitreous (Grant et al., 1986)

GH and IGF-I involvement in PDR: in vitro dataGH and IGFGH and IGF--I involvement in PDR: I involvement in PDR: in vitroin vitro datadata

•

Receptors for IGF-I on mammalian retinal microvascular cells

•

IGF-I induces release of plasminogen activator and increases DNA synthesis in retinal endothelium

•

GH can stimulate proliferation of human retinal endothelial cells (HREC)

•

Somatostatin receptors present on HREC•

Octreotide inhibits endothelial cell proliferation stimulated by IGF-I or b-FGF

••

Receptors for IGFReceptors for IGF--I on mammalian retinal I on mammalian retinal microvascularmicrovascular cellscells

••

IGFIGF--I induces release of I induces release of plasminogenplasminogen activator and activator and increases DNA synthesis in retinal endotheliumincreases DNA synthesis in retinal endothelium

••

GH can stimulate proliferation of human retinal GH can stimulate proliferation of human retinal endothelial cells (HREC)endothelial cells (HREC)

••

SomatostatinSomatostatin receptors present on HRECreceptors present on HREC••

OctreotideOctreotide inhibits endothelial cell proliferation inhibits endothelial cell proliferation stimulated by IGFstimulated by IGF--I or bI or b--FGFFGF

Stimulation of Endothelial Stimulation of Endothelial Proliferation by IGF and VEGFProliferation by IGF and VEGF

Retinal pigment epithelial cell (RPE)

Retinal endothelial cell

•

IGF-I stimulates VEGF production by RPE cells•

IGF-I and VEGF promote neovascularization by endothelial cell proliferation

VEGFIGF-I

PI3 kinase

P P

VEGF expression

HIF-1a

MAP kinase

Proliferation

IGF-I

P PP P

Treins et al. Mol Endocrinol. Epub before print. Smith et al. Nat Med. 1999;5:1390-1395.

Proposed Model for Local Inhibition of Proposed Model for Local Inhibition of NeovascularizationNeovascularization by by SomatostatinSomatostatin/ / SomatostatinSomatostatin AnaloguesAnalogues

Retinal pigment epithelial cell (RPE) Retinal endothelial cell

IGF-I VEGF

SHP-1PI3 kinase

VEGF expression

HIF-1a

MAP kinase

Proliferation

SHP-1

Somatostatin analogueSomatostatin

IGF-I

P P PP P

•

Somatostatin blocks IGF-I receptor activity and VEGF expression in RPE cells, possibly by activation of SHP-1 tyrosine phosphatase

•

Somatostatin blocks IGF-I and VEGF stimulation of endothelial proliferation, possibly by activation of SHP-1

Treins et al. Mol Endocrinol. Epub before print. Smith et al. Nat Med. 1999;5:1390-1395. Sall et al. Exp Eye Res. 2004;79:465-476. Baldysiak-Figiel et al. J Endocrinol 2004;180:417-24.

P

OctreotideOctreotide

Reduces Progression to HighReduces Progression to High--Risk PDRRisk PDR

Grant et al. Diabetes Care. 2000;23:504.

OctreotideOctreotide

Reduces Risk of Vitreous Hemorrhage Reduces Risk of Vitreous Hemorrhage in Patients with Prior Laser Photocoagulationin Patients with Prior Laser Photocoagulation

0 06 2

468

0

2

4

6

8

10

0 6 12 18 24 30 36

months

Treated Controls

num

ber o

f eye

s

Boehm et al. Horm Metab Res. 2001;33:300.

OctreotideOctreotide

--

Phase III StudiesPhase III Studies

•

Study 802 European; 3 arms Sandostatin LAR 20 and 30 mg, Placebo

•

Study 804 American; 2 arms Sandostatin LAR 30 mg, Placebo

Status: completed

Storia Storia nn°°

2 2 --

RuboxistaurinaRuboxistaurina

Hyperglycemia

OxidantsDiacylglycerol (DAG)

generationAdvanced

glycosylationend products

PKC activation

Vasculature Kidney HeartRetina

DAG

Nerves

DiabetesDiabetes--Induced Activation of PKCInduced Activation of PKC

PKC Activation in the VasculaturePKC Activation in the Vasculature

Increases:•

Basement matrix protein synthesis

•

Activation of leukocytes •

Endothelial cell activation and proliferation

•

Endothelial permeability•

Smooth muscle cell contraction

•

Cytokine activation, TGF-β

and VEGF, endothelin•

Angiogenesis

Hyperglycemia

Retinal vascular injury and dysfunction

Vascular leakage

Macular edema

Capillary nonperfusion

VEGF/VPF production

Proliferative retinopathy

Neovascularization

PKC-β

activation

PKC-β

activation

PKC-β

activation

PKC-β

activation

PKCPKC--ββ

iin Diabetic Retinopathyn Diabetic Retinopathy

PKCPKC--ββ

Inhibition and Retinal PermeabilityInhibition and Retinal Permeability

Retinal Vascular

Permeability*(arbitrary

units)

*Measured by vitreous fluorescein leakage. †P = .015. ‡P = .043.Reproduced with permission from Aiello LP et al. Diabetes. 1997;46:1473-1480.

Control 25 mg/kg/d oral LY333531

Vehicle

VEGF (2ng/eye)

024

68

101214

16182022 † ‡

PKC-β

InhibitorPKCPKC--ββ

InhibitorInhibitor

NNOOOO

NN

NN

OO

NN

CHCH33

CHCH33

HH Highly PKC selectiveHighly β

isoform selective

Orally bioavailable

Reduces retinal NVReduces DM-induced permNormalizes retinal blood flow

Ruboxistaurin

(RBX)

PKCPKC––ββ

Inhibition and DR trialsInhibition and DR trials

Phase IIIDM ME NPDR

32 mg v placebo

MBCM n=680

Phase II/IIIDiabetic ME Progression & Laser (CSMO)

DailyDME n=686

Phase II/IIINPDR Progression & Laser (CSMO)

8, 16, 32 mg Once

DRS n=252

Phase IbRBF & MCTOralPKC-β

inhibitionSTATUSSTATUSINDICATIONINDICATIONACTIONACTIONTRIALTRIAL

PKCPKC––ββ

Inhibition and DR trialsInhibition and DR trials

Phase IIIDM ME NPDR

32 mg v placebo

MBCM n=680

Phase II/III Completed

Sept 2002

Diabetic ME Progression & Laser (CSMO)

DailyDME n=686

Phase II/III Completed

April 2002

NPDR Progression & Laser (CSMO)

8, 16, 32 mg Once

DRS n=252

Phase Ib Completed

RBF & MCTOralPKC-β

inhibitionSTATUSSTATUSINDICATIONINDICATIONACTIONACTIONTRIALTRIAL

Progression of Diabetic Retinopathy or PhotocoagulationProgression of Diabetic Retinopathy or Photocoagulation

Aiello LP, et al. Diabetologia. 2003;46(suppl 2):A42.

Months6 12 18 24 30 36 42

Cum

ulat

ive

% o

f pat

ient

s

0

10

20

30

40

50

60

Placebo 8 mg RBX 16 mg RBX 32 mg RBX

Moderate Visual LossModerate Visual Loss (decrease of (decrease of ≥≥15 letters)15 letters)

*

* ***

* P < 0.05 32 mg RBX vs placebo

Aiello LP, et al. Diabetologia. 2003;46(suppl 2):A42.

Months6 12 18 24 30 36 42

Cum

ulat

ive

% o

f pat

ient

s

0

10

20

30

40

50

Placebo 8 mg RBX 16 mg RBX 32 mg RBX

PKCPKC––ββ

Inhibition and DR trialsInhibition and DR trials

Phase IIICompleted 2005

DM ME NPDR

32 mg v placebo

MBCM n=680

Phase II/III Completed Sept 2002

Diabetic ME Progression & Laser (CSMO)

DailyDME n=686

Phase II/III Completed April 2002

NPDR Progression & Laser (CSMO)

8, 16, 32 mg Once

DRS n=252

Phase Ib Completed

RBF & MCTOralPKC-β

inhibitionSTATUSSTATUSINDICATIONINDICATIONACTIONACTIONTRIALTRIAL

• Treatment with ruboxistaurin:– Demonstrated an effect (p = 0.038) on the

study outcome of moderate visual loss

Phase 3 DR StudyPhase 3 DR Study Trial ResultsTrial Results

Reduction…in sustained

moderate visual loss in eyes with diabetic macular

edema at baseline

(p=0.017)

Reduction…in sustained

moderate visual loss in eyes with

more severe diabetic

retinopathy (level 53) at

baseline (p=0.024)

Storia Storia nn°°

3 3 ––

Il sistema Il sistema reninarenina--angiotensinaangiotensina

Angiotensinogen

AT1

VasoconstrictionRenal sodium reabsorption

Cell growth and proliferation(remodelling)

Renin

Chymase

Trypsin

PeptidaseACE inhibitors

Angiotensin I

Angiotensin II

AT2

VasodilationApoptosis

DifferentiationAntiproliferation

Angiotensin type 1

receptor blockers

(ARBs)

Easthope SE, Jarvis B. Drugs 2002; 62:1253–1287.

ACE

The reninThe renin––angiotensinangiotensin

system (RAS)system (RAS)

The retinal RAS: renin levels in rat retinaThe retinal RAS: renin levels in rat retina

Sarlos S, et al. Invest Ophth Vis Sci 2005; 46: 1069–1077.

Ret

inal

reni

n co

nten

t (m

GU

/eye

)

Active renin

0123456789

10

Postnatalday 1

Postnatalday 7

Postnatalday 14

Postnatalday 21

Postnatalday 90

Sarlos S, et al. Invest Ophth Vis Sci 2005; 46: 1069–1077.

Representative computer- generated colour autoradiograph of specific ACE radioligand binding in retina of Sprague-Dawley ratShown is high (red), moderate (yellow and green) and low (blue) ACE binding

The retinal RAS: ACE levels in rat retinaThe retinal RAS: ACE levels in rat retina

Sarlos S, et al. Invest Ophth Vis Sci 2005; 46: 1069–1077.

Blood vessel

Ganglion cell layer

AT1 receptor immunolabelling in Sprague-Dawley rat retinas at postnatal day (P) 7Immunolabelling was observed in hyaloid vessels (double arrows), blood vessels in the inner limiting membrane and ganglion cell layer, and cells in the ganglion cell layer (single arrows)

The retinal RAS: The retinal RAS: ATAT11

--receptor distribution in rat retinareceptor distribution in rat retina

Funatsu H, et al. Br J Ophthalmol 2002; 86: 311–315.

The retinal RAS is activated in diabetes: vitreous The retinal RAS is activated in diabetes: vitreous angiotensinangiotensin

II levelsII levels

0

10

20

30

40

50

60

70

80A

ngio

tens

inII

leve

l in

vitr

eous

flui

d (p

g/m

l)

Human vitreous fluid

* p<0.0001

Non-diabeticpatient(n=16)

Diabeticpatient without

retinopathy(n=6)

Diabeticpatient withretinopathy

(n=51)

****

Funatsu H, et al. Br J Ophthalmol 2002; 86: 311–315.

The retinal RAS is activated in diabetic The retinal RAS is activated in diabetic retinopathy: vitreous VEGF levelsretinopathy: vitreous VEGF levels

0

500

1000

1500

2000

2500

3000

3500VE

GF

leve

l in

vitr

eous

flui

d (p

g/m

l)

Human vitreous fluid

* p<0.0001

Non-diabeticpatient(n=16)

Diabeticpatient without

retinopathy(n=6)

Diabeticpatient withretinopathy

(n=51)

****

Rat iris

Non-diabetic

Diabetic

Moravski CJ, et al. Am J Pathol 2003; 162: 151–160.

Dilated vessels

Normal vessels

Num

ber o

f PEC

sN

umbe

r of P

ECs

Inner retina

Iris

0

2

4

6

0102030405060

Ren-2 non-diabetic

Ren-2 diabetic

The RAS influences ocular endothelial cell The RAS influences ocular endothelial cell proliferation in diabetesproliferation in diabetes

Retinal endothelial cells:

VEGF-R2

Retinal pericytes:

VEGFRAGE and ROS

Retina in vivo: VEGFVEGF-R2DAG

Effect of ARBs

Angiotensin

II

AT1

-R ARBs

Clermont A, et al. J Hypertens 2006; 24: S73–S80.

Molecular effects of Molecular effects of angiotensinangiotensin

receptor receptor blockers on retinal vascular cells and tissueblockers on retinal vascular cells and tissue

Impact of RAS blockadeImpact of RAS blockade

1. Nagisa Y, et al. Diabetologia 2001; 43: 883–888.2. Ebrahimian TG, et al. Arterioscler Thromb Vasc Biol 2005; 25: 65–70.

Effect of candersartan

on VEGF expression

** **

VEG

F m

RN

A

VEG

F pr

otei

n le

vel (

% o

f con

trol

)

Control SPTZ SPTZ +

ACEI

SPTZ +

candesartan

Streptozocin-treated (SPTZ) mice2Diabetic stroke-prone spontaneously hypertensive rats (SHRSP) with streptozocin-induced diabetes1

*

p≤0.01 vs

control†

p≤0.01 vs

SPTZ‡

p<0.05 vs

control**

p<0.001 vs

SPTZ

*

†

‡

0.0

0.5

1.0

1.5

2.0

Control SPTZ + 1 mg/kg

0

50

100

150

200

SPTZ SPTZ + 3 mg/kg

candesartancandesartan

* *

Impact of RAS blockadeImpact of RAS blockade

Effect

of candesartan

on hypoxia-induced

neovascularisation

in mice

Nakamura H, et al. Eur J Pharmacol 2005; 512: 239–246.

Candesartan (mg/kg/day)

*p<0.05

Neo

vasc

ular

isat

ion

scor

e

n=15n=15n=16n=14n=16

0

1

2

3

4

5

6

7

8

Control 1 3 10 30

Lisinopril

better Placebo better

EUCLIDIncidence, progression and regression of diabetic

retinopathy in patients with type 1 diabetes

Chaturvedi

et al.

Lancet 351:28–31, 1998

Treatment by Treatment by lisinoprillisinopril:: (EUCLID, (EUCLID, LancetLancet 351, 28351, 28--31, 1998)31, 1998)

•

Reduces by 50% the risk of 1-step progression of DR on the EURODIAB scale (O.R. = 0.50; 95% CI = 0.28- 0.89; p<0.02)

•

Reduces by 80% the risk of progression to proliferative RD (O.R. = 0.20; 95% CI = 0.04-0.91; p<0.04)

(for a decrease of 3 mmHg in systolic BP)

DIRECTDIabetic REtinopathy Candesartan Trials

Three randomised placebo-controlled studies on the effects of the ARB candesartan on incidence and progression of diabetic retinopathy

DIRECT DIRECT --

Programme of investigator initiated and Programme of investigator initiated and led studiesled studies

•

DIRECT-Prevent 1 Type 1 diabetes without diabetic retinopathy

•

DIRECT-Protect 1 Type 1 diabetes with mild-to-moderate

diabetic retinopathy

•

DIRECT-Protect 2 Type 2 diabetes with mild-to-moderate

diabetic retinopathy

DIRECT Programme: DIRECT Programme: InclusionInclusion criteriacriteria

Number of patientsNumber of patients

14211421

19051905

19051905Age (years)Age (years)

1818--5050

1818--5555

3737--7575Diabetes duration (years)Diabetes duration (years)

11--1515

11--2020

11--2020MicroalbuminuriaMicroalbuminuria

NoNo

NoNo

NoNoBlood pressure (mmHg)Blood pressure (mmHg)

SBP SBP ≤≤130130

SBP SBP ≤≤130130

No HTN treatmentNo HTN treatment DBP DBP ≤≤85 85 DBP DBP ≤≤85 85 SBP SBP ≤≤130 130

DBP DBP ≤≤85 85 HTN treatment HTN treatment SBP SBP ≤≤160160

DBP DBP ≤≤90 90 Retinal grading levelRetinal grading level

10/1010/10

≥≥20/10 up to 20/10 up to ≥≥20/10 up to 20/10 up to (ETDRS scale)(ETDRS scale)

≤≤47/4747/47

≤≤47/47 47/47

DIRECTDIRECT--

DIRECTDIRECT--

DIRECTDIRECT--Prevent 1 Prevent 1 Protect 1Protect 1

Protect 2Protect 2

DIRECT DIRECT ProgrammeProgramme

309 centres

in 30 countries

Placebo od

Candesartan

32 mg odCandesartan

16 mg od

Placebo odPlacebo od

48 monthsfollow-up

Months -2 0 1 2 6 12 every6 months

DIRECT Programme: Individual study designsDIRECT Programme: Individual study designs

R

Retinal photographs annuallyUrinary albumin excretion rate

annually

Blood pressure

six monthlyAdverse events

six monthly

Investigations:

• The primary endpoint is - 2-step change in ETDRS level for incidence - 3-step change in ETDRS level for progression

• Secondary endpoints include - regression of retinopathy (3-step or 2-step sustained)

• Change in overall retinopathy severity

DIRECT Programme: Outcome measuresDIRECT Programme: Outcome measures

ETDRS ETDRS retinopathyretinopathy scalescale ((basedbased on 7on 7--field stereo field stereo photographsphotographs))

Levels

and

severity

on the Early Treatment of Diabetic Retinopathy Study scale used for the DIRECT Programme

10

DR absent

20

MA only

35

Mild NPDR

43

Moderate NPDR

47

Moderately severe NPDR

53

Severe NPDR

61, 65, 71, 75, 81

Proliferative DR

Level

Severity

DR

Diabetic retinopathyMA

MicroaneurysmsNPDR

Non-proliferative diabetic retinopathy

Diabetic retinopathyDiabetic retinopathy MMicroaneurysmsicroaneurysms onlyonly

Right

eye Left

eye

Level

20Level

20

Level

43Level

35

Right

eye Left

eye

Diabetic retinopathyDiabetic retinopathy 33--step step changechange

DIRECTDIRECT--Prevent 1Prevent 1

Effect of candesartan on incidence of retinopathy in type 1 diabetic patients

ÈÈ

vitale puntare sul numero giusto vitale puntare sul numero giusto …… ……

22--step o 3step o 3--step step progressionprogression??

• The primary endpoint is - 2-step change

in ETDRS level for

incidence - 3-step change in ETDRS level for progression

• Secondary endpoints include - regression of retinopathy (3-step or 2-step sustained)

• Change in overall retinopathy severity

DIRECT Programme: Outcome measuresDIRECT Programme: Outcome measures

No at riskPlacebo

710

644

585

518

347

87

0Candesartan

711

633

573

524

356

92

1

DIRECTDIRECT--Prevent 1: Retinopathy incidencePrevent 1: Retinopathy incidence 22--step changestep change

Time from randomisation

(years)

0.0

0.1

0.2

0.3

0.4

p=0.0508p=0.0508

PlaceboPlaceboCandesartanCandesartan

0 1 2 3 4 5 6

Cum

ulat

ive

prop

ortio

n

DIRECTDIRECT--Prevent 1: Retinopathy incidencePrevent 1: Retinopathy incidence 33--step changestep change

No at riskPlacebo

710

663

630

587

419

109

1Candesartan

711

651

615

587

422

108

1

0.0

0.1

0.2

0.3

0.4

0.5

p=0.003p=0.003

Cum

ulat

ive

prop

ortio

n

Time from randomisation

(years)0 1 2 3 4 5 6

PlaceboPlaceboCandesartanCandesartan

2-step change

*

Pre-specified adjustment for baseline diabetes duration, HbA1c

and SBP

DIRECTDIRECT--Prevent 1: Hazard ratios for Prevent 1: Hazard ratios for retinopathy incidence (retinopathy incidence (candesartancandesartan vsvs placebo)placebo)

HR HR 95% CI95% CI LowerLower

UpperUpper

UnadjustedUnadjusted

0.820.82

0.670.67 1.001.00

Adjusted*Adjusted*

0.880.88

0.720.72 1.071.07

3-step changeHR HR 95% CI95% CI

LowerLower

UpperUpper

UnadjustedUnadjusted

0.650.65

0.480.48 0.870.87

Adjusted* Adjusted* 0.710.71

0.530.53 0.950.95

DIRECTDIRECT--PreventPrevent 11:: Systolic and diastolicSystolic and diastolic blood pressureblood pressure

PlaceboCandesartan

Δ

SBP

--2.62.6

mmHg

Time from randomisation

(years)0 1 2 3 4 LVCF

60

70

80

90

100

110

120

130

mm

Hg

Δ

DBP

--2.72.7

mmHg

LVCF = Last Value Carried Forward

DIRECTDIRECT--Prevent 1: Change in ETDRS levelPrevent 1: Change in ETDRS level

CandesartanCandesartanPlaceboPlacebo

p=0.005p=0.005

0

10

20

30

50

60

70

2 4 ≥5

80

40

310Number of steps change in ETDRS from baseline to last visit

Patie

nts

(%)

DIRECTDIRECT--Protect 1Protect 1

Effect of candesartan on progression of retinopathy in type 1 diabetic patients

0.0

0.3

No at riskPlacebo

954

875

820

770

612

188

4Candesartan

951

863

814

767

626

195

5

0.2

0.1

p=0.8p=0.8Cum

ulat

ive

prop

ortio

n

Time from randomisation

(years)0 1 2 3 4 5 6

PlaceboPlaceboCandesartanCandesartan

DIRECTDIRECT--Protect 1: Retinopathy progression Protect 1: Retinopathy progression 33--step changestep change

DIRECTDIRECT--Protect 1: Retinopathy regressionProtect 1: Retinopathy regression

No at riskPlacebo

954

840

772

713

559

167

5Candesartan

951

820

773

728

591

187

5

0.0

0.1

0.2

0.3

0.4

Time from randomisation

(years)0 1 2 3 4 5 6

Cum

ulat

ive

prop

ortio

n

p=0.9p=0.9

PlaceboPlaceboCandesartanCandesartan

DIRECTDIRECT--Protect 1: Change in ETDRS levelProtect 1: Change in ETDRS level

p=0.03p=0.03

0

5

10

15

20

25

30

≤-5 -4 -3 -2 -1 0 1 2 3 4 ≥5

CandesartanCandesartanPlaceboPlacebo

Number of steps change in ETDRS from baseline to last visit

Patie

nts

(%)

DIRECTDIRECT--Protect 2Protect 2

Effect of candesartan on progression of retinopathy in type 2 diabetic patients

DIRECTDIRECT--ProtectProtect 2: 2: RetinopathyRetinopathy levelslevels at at baselinebaseline ((worstworst eyeeye))

Retinopathy level

20 35 43 -

470

25

50

75

100

MAonly

MildNPDR

ModerateNPDR

29%

54%

17%Patie

nts

(%)

ÈÈ

vitale puntare sul numero giusto vitale puntare sul numero giusto …… ……

DR DR progressionprogression

o o regressionregression??

• The primary endpoint is - 2-step change in ETDRS level for incidence - 3-step change in ETDRS level for progression

• Secondary endpoints include - regression

of retinopathy

(3-step or 2-step sustained)

• Change in overall retinopathy severity

DIRECT Programme: Outcome measuresDIRECT Programme: Outcome measures

DIRECTDIRECT--Protect 2: Retinopathy progressionProtect 2: Retinopathy progression 33--step changestep change

Time from randomisation

(years)No at riskPlacebo

954

845

794

737

513

112

3Candesartan

951

848

807

737

540

123

0

0.0

0.1

0.2

0.3

0.4

Cum

ulat

ive

prop

ortio

n

p=0.2p=0.2

0 1 2 3 4 5 6

PlaceboPlaceboCandesartanCandesartan

DIRECTDIRECT--Protect 2: Retinopathy regressionProtect 2: Retinopathy regressionC

umul

ativ

e pr

opor

tion

No at riskPlacebo

954

812

760

713

510

93

1Candesartan

951

811

755

692

492

100

0

0.0

0.1

0.2

0.3

0.4

p=0.009p=0.009

Time from randomisation

(years)0 1 2 3 4 5 6

PlaceboPlaceboCandesartanCandesartan

*

Pre-specified adjustment for baseline level of retinopathy, diabetes duration, HbA1c

, UAER, SBP and antihypertensive treatment**

Pre-specified adjustment

for baseline level of retinopathy, diabetes

duration, HbA1c

, UAER, antihypertensive treatment and SBP during study

HR HR 95% CI95% CI LowerLower

UpperUpper

UnadjustedUnadjusted

1.341.34

1.081.08 1.681.68

Adjusted*Adjusted*

1.381.38

1.111.11 1.731.73

Adjusted**Adjusted**

1.331.33

1.061.06 1.671.67

DIRECTDIRECT--Protect 2: Hazard ratios for Protect 2: Hazard ratios for retinopathy regression (retinopathy regression (candesartancandesartan vsvs

placebo)placebo)

DIRECTDIRECT--Protect 2: Protect 2: Regression of DR by Regression of DR by baseline levelbaseline level

CandesartanPlacebo

Cum

ulat

ion

prop

ortio

n

0 1 2 3 4 5 6Time from randomisation

(years)

0.0

0.1

0.2

0.3

0.4 Ret.levelRet.level

>35>35p=0.25p=0.25

0.0

0.1

0.2

0.3

0.4 Ret.levelRet.level

= 35= 35p=0.009p=0.009

0.0

0.1

0.2

0.3

0.4 Ret.levelRet.level

= 20/20= 20/20p=0.08p=0.08

Cum

ulat

ion

prop

ortio

nC

umul

atio

npr

opor

tion

DIRECTDIRECT--Protect 2: Change in ETDRS levelProtect 2: Change in ETDRS level

≤-5 -4 -3 -2 -1 0 1 2 3 4 ≥5Number of steps change in ETDRS from baseline to last visit

0

5

10

15

20

25

30

Patie

nts

(%) p=0.003p=0.003

CandesartanCandesartanPlaceboPlacebo

ÈÈ

vitale puntare sul numero giusto vitale puntare sul numero giusto …… ……

changechange

in in overalloverall

DR DR severityseverity??

• The primary endpoint is - 2-step change in ETDRS level for incidence - 3-step change in ETDRS level for progression

• Secondary endpoints include - regression of retinopathy (3-step or 2-step sustained)

• Change in overall retinopathy severity

DIRECT Programme: Outcome measuresDIRECT Programme: Outcome measures

0

10

20

30

DIRECT: Change in ETDRS levelDIRECT: Change in ETDRS levelCandesartanPlacebo

p=0.005

0

20

60

40

Number of steps change in ETDRS from baseline to last visit

p=0.03

≤-5 -4 -3 -2 -1 1 2 3 4 ≥500

10

20

30

p=0.003

DIRECT-Prevent 1

DIRECT-Protect 1

DIRECT-Protect 2

80

Patie

nts

(%)

Patie

nts

(%)

Patie

nts

(%)

Storia Storia nn°°

4 4 ––

Il Il fenofibratofenofibrato

Retinopathy in the FIELD TrialRetinopathy in the FIELD Trial

3

5

0

1

2

3

4

5

6

Fenofibrate Placebo

Patie

nts

(%)

Overall Study: Laser Treatment for Retinopathy

Keech

et al. Lancet 2007; DOI:10.1016/S0140-6736(07)61607-9 Ref

P=0.0003

F P

Retinopathy in the FIELD TrialRetinopathy in the FIELD Trial

2,4

1,5

3,4

2,2

0

0,5

1

1,5

2

2,5

3

3,5

4

Any Maculopathy Proliferative Retinopathy

Patie

nts

(%)

Overall Study: First Laser Treatment Events

Keech

et al. Lancet 2007; DOI:10.1016/S0140-6736(07)61607-9 Ref

P=0.002

P=0.02

F FP P

Retinopathy in the FIELD TrialRetinopathy in the FIELD Trial

9,6

11,4

3,1

12,311,7

14,6

0

2

4

6

8

10

12

14

16

All Patients No Pre-ExistingRetinopathy

Pre-Existing Retinopathy

Patie

nts

(%)

Ophthalmology Substudy: 2-Step Progression of Retinopathy

Keech

et al. Lancet 2007; DOI:10.1016/S0140-6736(07)61607-9 Ref

P=0.19 P=0.87

P=0.004

PPP FFF

Retinopathy in the FIELD TrialRetinopathy in the FIELD Trial

In diabetic patients, 5 years of treatment with fenofibrate:•Reduced the need for laser treatment for diabetic

retinopathy•Reduced 2-step progression of retinopathy grade in

patients with but not without pre-existing retinopathy•Did not reduce fasting glucose, A1c or blood

pressure2

Keech

et al. Lancet 2007; DOI:10.1016/S0140-6736(07)61607-9

Ref

ÈÈ

vitale puntare sul numero giusto!vitale puntare sul numero giusto!

Epilogo Epilogo ……

VEGF, GH, VEGF, GH, IGF, FGF, IGF, FGF,

HGF, PDGF, HGF, PDGF, TGF, TGF, AngAng, , ATII, and ATII, and

many many moremore……

Growth Factor Mediation in Diabetic Growth Factor Mediation in Diabetic RetinopathyRetinopathy

Ang = angiopoietin; ATII = angiotensin II; FGF = fibroblast growth factor; GH = growth hormone; HGF = hepatic growth factor; IGF = insulin-like growth factor; PDGF = platelet-derived growth factor; TGF = transforming growth factor; VEGF = vascular endothelial growth factor.

DAG = diacylglycerol; IP3 = inositol 1,4,5-trisphosphate; KDR = kinase insert domain receptor; Pl3 = phosphatidylinositol 3-kinase; PLCγ

= phospholipase C-γ; PIP2 = phosphatidylinositol 4, 5 biphosphate. Xia P et al. J Clin Invest. 1996;98:2018-2026.

KDRKDR

VEVE

PI3 PI3 KinaseKinasePLCPLCγγ--PP

PLCPLCγγ

PIPPIP22DAG andDAG and IPIP33

PermeabilityPermeability NeovascularizationNeovascularization

PKCPKC

GFGF

Mechanism of VEGF ActionMechanism of VEGF Action

Hosoya KI, et al. Biol Pharm Bull 2005; 28: 1–8.

BloodBlood––retinal barrierretinal barrier

Neurones Retinalcapillaryvessel

Glia

Pro-barrier factorse.g. Factor X

Permeability factorse.g. VEGF and histamine

Tight junctionsthat form the

blood–retinal barrier

BloodBlood––retinal barrierretinal barrier

Gardner TW, et al. Surv Ophthalmol 2002; 47: S253–S262.

Neurones

Glia

Reduction

in pro-barrier factors

e.g. Factor X

Increase

in permeability factors

e.g. VEGF and histamine

Retinalcapillaryvessel

Compromisedblood–retinal

barrier

BloodBlood––retinal barrier in diabetesretinal barrier in diabetes

Gardner TW, et al. Surv Ophthalmol 2002; 47: S253–S262.

•

VEGF also disrupts the expression of proteins maintaining the tight junctions of the blood– retinal barrier

•

As a result, vascular permeability increases

Retinalcapillaryvessel

Compromisedblood–retinal

barrier

VEGF: key player in diabetic retinopathyVEGF: key player in diabetic retinopathy

Gardner TW, et al. Surv Ophthalmol 2002; 47: S253–S262.

Inhibition of Inhibition of Angiogenesis/PermeabilityAngiogenesis/Permeability

Blood vessel

VEGF receptor Endothelial cell

Anti-VEGFtherapy

VEGFProliferation

MigrationPermeability

Multiple signal- transduction pathways

(including PKC-β)

Signal Signal Transduction Neovascularization/Edema

Triamcinolone

NVD, NVE, DME

DME = diabetic macular edema; NVD = neovascularization

of the disc; NVE = neovascularization

elsewhere.

Agent Action Indication

Pegaptanib sodiumIntravitreal aptamer VEGF

inhibitorDME

Ranibizumab Intravitreal humanized anti- VEGF antibody fragment

DME

Bevacizumab Anti-VEGF antibody DME

Triamcinolone acetonideIntravitreal steroid injection DME

AgentsAgents

forfor

intraintra--vitrealvitreal

useuse

Grazie per lGrazie per l’’attenzione e attenzione e …… buona fortuna a tutti!buona fortuna a tutti!