Larry Kauvar, PhDFounder and VP Chief Scientific Officer

4th World Congress on VirologySan Antonio, TX8 October 2014

2

Native Human Antibody (mAb)

CellSpotTM Platform

Trellis Clones Native Human mAbs from BloodProcess is fast enough to address emerging disease threats

Advantages of Native Human mAbs

ImmuneResponse

NativeAntibody

AffinityMaturation

TherapeuticRelevance

High Affinity

Picomolar Kd mAbs

Screened againsthuman proteome

Excellent safety profile

Correlate mAb properties with clinical

outcomes

Risk reductionfor IND candidate

3

Natural immunogen andexposure route

Target relevant epitopes

Superb efficacy and safety compared to any other drug class

4

Miniaturization (without liquid handling)

footprint is ~150 µm diameter

Antibodies from 3 sibling B-cells bind Antigen e

Multiplexing

Millions of B-cells screened from 25-50 donors to provide

comprehensive survey of the human repertoire

B-cells as rare as 1 in 100,000 are readily identified, and the mAb is then cloned by single cellcDNA PCR

~100 fg mAb per spot

Antigen a

Antigen b

Antigen c

Fluorescent beads

(9 types via patented combinatorial coloring)

Antigen d

Antigen e

CellSpot: Merger of Biotech With High Tech Isolate antibodies from single B-cells, after screening millions

2 million PBMCs (per plate)

B-Cell Culture

Native Human mAb

Master Plates

CellSpot: Exploit the Mature Immune Response

CellSpot5 days

•Limiting dilution cell cloning

•cDNA cloning of mAb H+L mRNA

Single Cell FootprintSingle Cell Profile

gigabytes kilobytes

Replicate Plates

SURVEY

CLONING

40x mag40x mag

200 memory B-cells (per well)

5

• Interrogate circulating memory B-cells from donor blood • Bias search for mAbs with high affinity to targets (Kd <10 nM)

6

Infectious Disease Programs

Trellis mAbs Address Major Unmet Medical Needs

RSV (respiratory syncytial virus)• Superior efficacy vs Synagis (>$1B sales)

• Superior in post-infection treatment, for which Synagis has not been approved

CMV (cytomegalovirus)• Leading cause of transplant failures

• Only current drug is Valcyte™: $700M/yr• Too toxic for bone marrow transplant

• Also leading cause of maternal infection that contributes to stillbirth and birth defects

Influenza• Existing drug Tamiflu™: ~$1B/year

• Limited efficacy and drug resistance is emerging globally

• Trellis program licensed to ContraFect Q1 2014

Bacterial biofilms• Implicated in 60-85% of infections (CDC data)

• Major cause of antibiotic drug failure• Novel target enables disruption of biofilm

• Trellis mAb binds target homologs from both Gram-positive and Gram-negative bacteria

Bacterial surface target• Iron Transporters are essential for viability• Conserved domains found in Staph and Strep

• Efficacy in murine post-infection treatment model for Trellis mAb against Strep homolog

Human mAb against RSVDirect Antiviral

AND

Prevents Viral Disruption of Immune Response

F-proteinmembraneG-protein

RSV Viral Particle

SynagisTarget

Trellis mAbTargets Both

F-Protein

G-Protein

Target Function

• Virus entry into host epithelial cells (fusion protein)

• Virus attachment to respiratory epithelium

• Modifies host immune response to favor virus persistence

solubleG-protein

8

RSV: 11 genes, 2 Major Coat Proteins (F and G)Respiratory Syncytial Virus

Conserved Motif Within Variable G-ProteinHigh conservation and low immunogenicity suggests a vital function

Plotnicky et al. 2002 Virology 303:130

Hole in human repertoireeven in vaccinated people

Pepscan immunerepertoire data

RSV Gprotein

9

• Central conserved motif• CX3C homolog

• Motif is invariant across 75 strains

• Key epitope has low immunogenicity

• Pepscan array probed with sera from vaccinated subjects

Donors were largely healthy nurses on RSV wards; an average of 800,000 B-cells were screened from each donor

10

20 million B cells screened from 30 RSV exposed donors

CellSpot surveys patient mAb repertoires and identifies target Abs (red bars)

Desired Strain-Independent Antibodies are Rare

desiredantibodies

Sample from which lead candidate was isolated

CellSpot multiplexed screen identified mAbs x conserved motif on G-protein

Anti-G is an Excellent Direct Antiviral100x more potent than Synagis

11

In vitro plaque reduction – RSV virus A2complement dependent

Day +3 treatment with anti-G rapidly reduced BAL cell inflammationEffect was pronounced at Day +5, and sustained at Days +7, +10, +14

*p<0.05

12

Anti-G Reduced Inflammatory BAL Cell Influx➔

Dr. Lia Haynes, CDC

•Trellis 3D3 and backup 2B11 performed similarly•Synagis showed no effect vs. controls

Trellis

Bre

ath

Dis

ten

sio

n (

um

)• Mice infected with RSV Line 19F (known for increased airway reactivity)• Breath distension of peripheral arteries (pulse oximetry) reflects pulmonary obstruction

143-6C 131-2G

13

Anti-G Improved Lung Function➔

non-immune IgGas a control

no RSV control

Dr. Larry Anderson, Emory University

• Day +3 treatment with murine anti-G mAb restored pulmonary function at Day +6

• No effect with murine anti-F mAb

14

Day 5 viral load

Dissect Anti-viral from Anti-inflammatory Activity

•Line 19F known to induce high mucus production and airway inflammation

•Prophylaxis with full length mAb suppresses viral load

Full IgG vs truncated F(ab’)2 (full IgG minus the Fc domain)

mucus production

IgGF(ab’)2 RSV IgGRSV

Dr. Larry Anderson, Emory University

F(ab’)2 ø

F(ab’)2: no activity asanti-viral agent

F(ab’)2: full activity asanti-inflammatory agent

ø

Dr. Ralph Tripp, University of Georgia

Anti-G mAb counteracts suppressive effect of G protein enhanced IFN-➔ αAnti-F mAbs skew IFN-α response in a deleterious direction

15

MOA: Anti-G mAb Restores Acute IFN-α Antiviral Response

IFN-α in plasmacytoid dendritic cells • G-protein suppresses IFN-α• Mutating CX3C prevents the effect• Fab of 131-2G has comparable

efficacy

Dr. Larry Anderson, Emory University

IFN-α in NHBE cells• G protein suppresses IFN-α

• F protein stimulates IFN-α• Anti-G mAb restores IFN-α

• Anti-F mAb suppresses IFN-α

G G F F mock + + 3D3 Synagis

Day

Airw

ay R

esis

tanc

efo

ld in

crea

se o

ver n

orm

al a

t 50

mg/

mL

MCh

Trellis 3D3 (anti-G mAb) vs Synagis (anti-F mAb)

16

Synagis exacerbates airway inflammation, Trellis mAb ameliorates it

Dr. Erwin Gelfand, MD, Chairman Pediatrics, National Jewish

tracheostomized mouse model

Human mAb against CMVHigh Affinity

AND

Blocks the Virus’ Broad Cell Tropism

Trellis TRL345: human mAb x Conserved gB(AD-2)

18

5 million B-cells screened, 30 mAbs cloned TRL345 (Kd ~50 pM)➔

TRL 345 EPITOPE

Trellis mAb TRL345: High Potency anti-gB(AD-2)

19

In vitro plaque reduction – VR1814 in ARPE-19 cells

TRL345: Neutralizes CMV’s Broad Cell Tropism

20

Sharp contrast to published mAb (1F11) against CMV pentameric complex (red)

1F11

TRL345

Efficacy in ex vivo Placental Infection Model

21

Placental Infection Model• Placental fragments grown ex vivo on Matrigel

extend villi and mimic normal invasive growth into uterine wall

• Virus strain VR1814 suppresses placental growth mimicking intra-uterine growth restriction

Most realistic model for predicting efficacy in man (HCMV does not infect animals)

Summary: Better Screening Better mAbs➔

RSV CMV

Lenore Pereira, Takako Tabata,Matthew Petttt, Mitsuru TsugeJune-Fang Hoover

Stuart P. Adler, Xiaohong Cui, Michael A. McVoy

SBIR grant 1R44AI102396-01

Ralph Tripp

Larry Anderson

Lia Haynes

Erwin Gelfand

F. Eun-Hyung Lee,Ed Walsh