Factor IXa InhibitionAptamer Technology Overview and

First Results with RB006/RB007Mauricio G. Cohen, MD

Associate Professor of MedicineDirector, Cardiac Cath Lab

Disclosure Statement of Financial InterestDisclosure Statement of Financial Interest

Within the past 12 months, I or my spouse/partner have had a Within the past 12 months, I or my spouse/partner have had a financial interest/arrangement or affiliation with the organization(s) financial interest/arrangement or affiliation with the organization(s) listed below.listed below.

Affiliation/Financial RelationshipAffiliation/Financial Relationship CompanyCompany

Grant/Research SupportGrant/Research Support REGADO BIOSCIENCESREGADO BIOSCIENCES

Search for the Ideal Anticoagulant

• Efficacy Ability to prevent thrombosis

• Safety Low risk of bleeding

• Titratability Ability to adjust the level of anticoagulation to individual clinical needs

• Reversibility Ability to safely, rapidly and predictably neutralize the anticoagulant effect when clinically indicated

• Convenience Daily single-bolus injections without need for continuous infusions or routine monitoring

MonoclonalAntibody

Aptamer

Aptamers: Nucleic Acids and Monoclonal Antibodies

Rusconi CP et al., Nature 2002;419:90-94

Aptamer ReversalAgent

Aptamers Encode Their Own Control Agents

Rusconi CP et al., Nature 2002;419:90-94

Aptamer

ReversalAgent

Aptamers Encode Their Own Control Agents

Rusconi CP et al., Nature 2002;419:90-94

REG1 Anticoagulant System

RB006 Anticoagulant aptamer

RB007Active control agent

• Synthetic single strand oligonucleotides

• Metabolized by nucleases in the blood with no ‘active’ metabolites

• No protein binding

• Specific affinityfor RB006

• Very short half life(<5min)

• 5 Kda (15 nucleotides)

7

• Specific affinityfor Factor IXa

• Long half life (>24hr)

• 50 Kda (31 nucleotides+ 40 kDa PEG)

Rationale for Targeting FIXa

TF-bearing cellTF-bearing cell

Activated plateletlatelet

PlateletPlatelet

VIIaVIIa

X

XaXa

VIIaVIIa

IXIX

IXaIXa

IXaIXa

XIaXIa

IXIX

II

X

IIaIIa

II

Propagation

Amplification

Initiation

XaXa IIaIIa

FIXa inhibitorFIXa inhibitor

TF Va

TF

VIIIaVa

Monroe DM. Arterioscler Thromb Vasc Biol 2002;22:1381-1389.

Rationale for Targeting Factor IXa

• FVIIIa/FIXa activation of FX is the rate limiting step in thrombin generation FIX knockout mice lack occlusive clot formation following vascular

injury due to insufficient generation of thrombin to form platelet aggregates.

• FIXa concentration is lower than Xa and thrombin, making high levels of target inhibition more readily achievable

• High Factor IX levels are associated with increase in ACS and venous thromboembolism Transgenic mice overexpressing FIXa have a shorter lifespan and

develop arterial thrombosis and myocardial fibrosis with vascular distribution patterns similar to those of ischemic cardiomyopathy in humans

• Hemophilia B Carriers-Reduced CHD Mortality

• Foreign materials (eg. catheters and guidewires) lead directly to FIX activation

REG1 Phase 1 Studies- Overview

10

Study Design Treatment Groups nSingle dose, dose escalation in healthy volunteers

IV injection of RB006 (15, 30, 60, 90 mg) and RB007 (30, 60, 120, 180 mg) alone and in combination

84

Single dose, dose escalation in patients with stable coronary artery disease (CAD)

IV injection of RB006 (15, 30, 50, 75 mg) alone and in combination with RB007 (30, 60, 120, 150 mg)

49

Multiple dose in healthy volunteers

IV injection of RB006 (0.75 mg/kg) followed by RB007 (dose ranging from 0.094 to 2 mg/kg) every other day for 6 days

39

Dyke C, et al. Circulation 2006;114:2490-2497Chan MY, et al. Circulation 2008;117:2865-2874

Chan MY, et al. J Thromb Haemost 2008; 6:789–96

Total: 172 Total: 172

CLIN101 – Phase 1A Study

• Study Design 85 healthy volunteers Multi-center, randomized, subject blinded, placebo controlled Evaluate safety of dose escalation of REG1 system or components and

pharmacokinetic/pharmacodynamic relationships Single-dose, dose escalation through 4 dose levels RB006, RB007, and REG1 treatment arms at each dose level

• Results 1 SAE but no trend of safety signals RB006 produced dose dependent aPTT levels RB007 neutralized observed pharmacodynamic effects of RB006

CLIN101 – REG1 Activity in Healthy Volunteers

ULN

LLN

Inject RB007

Time Post RB006 Injection (hrs)

AP

TT (

secon

ds)

Placebo/Placebo

15 mg RB006/30 mg RB007

30 mg RB006/60 mg RB007

60 mg RB006/120 mg RB007

90 mg RB006/180 mg RB007

Time Post RB006 Injection (hrs)

AP

TT (

secon

ds)

Inject RB007

ULN

LLN

Placebo/Placebo

Dyke C, et al. Circulation 2006;114:2490-2497

Stable CAD – Phase 1B Study

Study Design 50 patients w/ stable CAD on aspirin/clopidogrel

• 56-68 years of age

Multi-center, randomized, double-blind, placebo-controlled Evaluate safety of dose escalation of the REG1 system and

pharmacokinetic/pharmacodynamic relationships Single-dose, dose escalation through 4 dose levels RB006 and REG1 treatment arms at each dose level

Results No SAE’s or safety signals RB006 produced dose-dependent aPTT levels RB007 neutralized observed pharmacodynamic effects of RB006

Stable CAD – Phase 1B StudyResults

Time Post RB006 Administration (hrs)

AP

TT (

secon

ds)

Placebo/Placebo

15 mg RB006/30 mg RB007

30 mg RB006/60 mg RB007

50 mg RB006/100 mg RB007

75 mg RB006/150 mg RB007

Inject RB007

ULN

LLN

Chan MY, et al. Circulation 2008;117:2865-2874

Repeat-dose – Phase IC Study

Study Design 38 healthy volunteers Single-center, randomized, double-blind, placebo controlled Primary endpoints:

• Evaluate safety and tolerability of repeated doses of REG1 system

• Determine the optimal dose ratio for RB007 and RB006

3 consecutive weight-adjusted, drug-antidote treatment cycles or double placebo

Fixed doses of RB006 followed by titrated dose of RB007 (2:1 – 0.125)

Results Achieved highly reproducible aPTT levels with repeat doses of RB006 Reversed aPTT levels with RB007 dose-dependently and reproducibly

Repeat-dose – Phase IC StudyAntidote Dose Response

0.2:1 AD:DR

1:1 AD:DR

0.3:1 AD:DR

2:1 AD:DR

Placebo

0.125:1 AD:DR

Time Post RB006 Administration (hrs)

AP

TT (

secon

ds)

Inject RB007

ULN

LLN

A:D Ratio 0.5:1 0.3:1 0.2:1 0.125:1

% Reversal 84±2.7% 74±5.9% 51±6.4% 41±8.0%

Chan MY, et al. J Thromb Haemost 2008; 6:789–96

0.5:1 AD:DR

Repeat-dose – Phase IC StudyActivity In Healthy Volunteers

Low inter/intra-subject variability

Day 1 Day 3 Day 50

20

40

60

80

100 Placebo

Group 1

Group 2

Group 3

AP

TT (

sec)

n=38 (healthy volunteers)n=38 (healthy volunteers)

Chan MY, et al. J Thromb Haemost 2008; 6:789–96

Phase 1 Program Summary

Phase 1 Program Highlights:• Demonstrated safety of RB006, controlling agent (RB007)

and the overall REG1 system • Demonstrated controlling agent efficacy• No known drug interactions with common anti-platelet

therapy• Demonstrated RB006 and RB007 PK and elimination• Understanding of relationship between RB006 PK and PD• Identified optimal dose of RB006 for maximal FIXa inhibition• Demonstrated ability to titrate the controlling agent • Ability to proceed to Phase II development of REG1 in PCI

and ACS

18

Dyke C, et al. Circulation 2006;114:2490-2497Chan MY, et al. Circulation 2008;117:2865-2874

Chan MY, et al. J Thromb Haemost 2008; 6:789–96

PCI Pilot – Reversal PCI

• Feasibility study comparing the REG1 system with UFH in stable CAD patients undergoing elective PCI

• Multi-center, open-label, randomized (10/07–10/08) Black Hills Cardiology (Rapid City, SD)

Henry Ford Hospital (Detroit, MI)

University of North Carolina at Chapel Hill (NC)

The Care Group (Indianapolis, IN)

Hospital Italiano (Buenos Aires, Argentina)

• Central Coordination: Duke Clinical Research Institute

• Primary Endpoint Major Bleeding using the ACUITY bleeding criteria until hospital

discharge or 48 hours whichever occurs first. Composite of death, nonfatal myocardial infarct (MI), and urgent

target vessel revascularization (TVR) through Day 14

PCI Pilot – Reversal PCIStable CAD pts undergoing PCI

All on ASA and Clopidogrel preload (>6hs)Stable CAD pts undergoing PCI

All on ASA and Clopidogrel preload (>6hs)

Roll-in Phase: 2 patientsReg 1 system + Eptifibatide

RB007:RB006 (0.2:1)

Roll-in Phase: 2 patientsReg 1 system + Eptifibatide

RB007:RB006 (0.2:1)

Arm 1: 12 patients5:1 randomization

Heparin vs. Reg1 w/partial reversalRB007:RB006 (0.2:1)

Arm 1: 12 patients5:1 randomization

Heparin vs. Reg1 w/complete reversal

Complete Reversal @ 4 hsSheath Pull

Immediate Complete Reversal Sheath Pull

Complete Reversal @ 4 hsSheath Pull

Safety Committee Review

RB006 dose:1mg/kg in all subjects

RB007:RB006 (1.8:1)RB007:RB006 (1.8:1)

RB007:RB006 (1.8:1)RB007:RB006 (1.8:1)

RB007:RB006 (2.0:1)RB007:RB006 (2.0:1)

Timeline of Procedures

Baseline DataBaseline Data

StudyDrug

StudyDrug

5 min5 min 15 min15 min

ACTPTT (lab)

Whole Blood PTT (POC)

ACTPTT (lab)

Whole Blood PTT (POC)

EndEnd

PCIPCI

Informed consent will be executed prior to administration of any sedativesClopidogrel 600 mg loading dose and ASA 250-500 mg at least 4 hours prior to PCIPatients who receive heparin during diagnostic cath will wait at least 4 hours for the PCI procedure

Informed consent will be executed prior to administration of any sedativesClopidogrel 600 mg loading dose and ASA 250-500 mg at least 4 hours prior to PCIPatients who receive heparin during diagnostic cath will wait at least 4 hours for the PCI procedure

Immediately Post PCI

Roll-In andGroup I:

Partial Reversalor

Group II:Complete Reversal

andSheath Pull

Immediately Post PCI

Roll-In andGroup I:

Partial Reversalor

Group II:Complete Reversal

andSheath Pull

4 hoursRoll-In and

Group IComplete Reversal

and Sheath Pullor

HeparinSheath Pull

4 hoursRoll-In and

Group IComplete Reversal

and Sheath Pullor

HeparinSheath Pull

TnT, CKMB, CK q8h x 3TnT, CKMB, CK q8h x 3

IndefiniteASA

Clopidogrel recommend12 months

IndefiniteASA

Clopidogrel recommend12 months

14 daysEnd of Follow-up

14 daysEnd of Follow-up

Baseline Characteristics

REG 1 System Control

Partial Reversal

N = 10

CompleteReversal

N = 10

UFHN = 4

Age 63 (58, 68) 64 (55, 65) 64 (61, 71)

Male gender 7 (70%) 8 (80%) 1 (25%)

Weight (kg) 86 (80, 89) 101 (93, 115) 96 (90, 101)

Diabetes 2 (20%) 4 (40%) 1 (25%)

Serum Cr (mg/dL) 1.0 (0.9, 1.2) 1.0 (0.9, 1.1) 0.9 (0.9, 1.0)

Current smoker 1 (10%) 2 (20%) 1 (25%)

Prior MI 3 (30%) 3 (30%) 0

Prior PCI 5 (50%) 5 (50%) 1 (25%)

Procedural CharacteristicsREG 1 System Control

Part ReversalN = 10

Comp ReversalN = 10

UFHN = 4

Lesions treated 14 9* 5

Two-vessel PCI 4 (40%) 1 (10%) 1 (25%)

Procedure duration (min) 20 (13,37) 16 (11,30) 39 (33,41)

Diameter Stenosis (%) 90 (70, 90) 90 (80, 90) 90 (80, 90)

Stent use per patient DES (% of stents) Stent diameter (mm) Stent length (mm)

10 (100%)4 (40%)

3.0 (3.0, 3.5)17 (12, 24)

9 (90%)5 (55%)

2.9 (2.5, 3.0)14 (12, 28)

4 (100%)3 (75%)

2.9 (2.8, 3.3)16 (14, 20)

Post-proc TIMI 3 flow 14 (100%) 10 (100%) 5 (100%)

Time RB006 to RB007 Partial reversal (min) Complete reversal (min)

62 (36, 89)278 (272, 284)

…54 (49, 58)

……

Time to sheath pull (min) 282 (266,308) 46 (42,52) 217 (130,300)

Primary Outcomes Measures

REG1 System Control

Partial Reversal

N = 10

TotalReversal

N = 10

UFHN = 4

Modified Acuity Bleeding Events*

0/10 0/10 1/4

Death, MI or Urgent TVR through 14 days

1/10 1/10** 1/4

* Through Hospital Discharge or 48 hrs, whichever occurs first** Urgent TVR on D6, Index lesion/stent patent, not related to REG1

PartialReversalMedian

Pharmacodynamics – WB PTT POC

Total ReversalMedian

Baseline 5 min PostStudy Drug

15 min PostStudy Drug

End of PCI

Wh

ole

blo

od

PTT (

secon

ds)

40

120

80

160

200

82 83

151 147 145.5 146.5 145 139

Mean

Stable and Predictable Anticoagulation

Interquartile range of max RB006 effect

Arm 1:Partial

Reversal

Arm 2: Total

Reversal

Acti

vate

d C

lott

ing

Tim

e (

secon

ds)

150

250

200

300

350

Control: UFH

Baseline 5 min PostStudy Drug

15 min PostStudy Drug

End of PCI 15 min post 1st RB007

Dose

15 min post2nd RB007 Dose

Pharmacodynamics – ACTStable and Predictable Anticoagulation

Conclusions: Reversal PCI

• All procedures were successfully completed.

• No signs of catheter or guidewire thrombosis.

• Monitoring by ACT, POC aPTT and plasma aPTT demonstrated measurable differences in both partial and total RB007 reversal doses.

• The REG1 System was well tolerated.

• RB007 facilitated early sheath removal.

• RB006 (1mg/kg) demonstrated rapid onset with consistent coagulation measures during PCI.

In Summary…

• The REG 1 System offers the possibility of balancing the bleeding-ischemia risk in PCI patients

• This concept can be expanded to other clinical scenarios in which anticoagulation can be tailored to individual patient needs

• The Phase 2b RADAR trial will evaluate the safety and efficacy of the REG1 System in 800 acute coronary syndrome patients undergoing cardiac catheterization.