Increases in CD4 Counts and Effects on HIV in Aviremic HIV-infected Subjects Infused with Zinc Finger Nuclease (ZFN) CCR5 Modified Autologous

CD4 T-cells (SB-728-T) and the use of Cytoxan prior to the infusion

Raul H. Morales-Borges, MDMedical Director

Puerto Rico Region, Biomedical ServicesAmerican Red Cross

For the ARC Medical Directors Meeting Sept. 12, 2012

Increases in CD4 Counts and Effects on HIV in Aviremic HIV-infected Subjects Infused with Zinc Finger Nuclease (ZFN) CCR5 Modified

Autologous CD4 T-cells (SB-728-T)

W Tang1, J Lalezari2, C June3, P Tebas3, D Stein4, R Mitsuyasu5, G Lee1, M Giedlin1, S Wang1 and D Ando1.

1Sangamo BioSciences Inc, Richmond, CA; 2Quest Clinical Research, San Francisco, CA; 3PENN, Philadelphia, PA; 4Albert Einstein College of Medicine, Bronx, NY; and 5UCLA, Los Angeles, CA

Disclosure• No conflicts of interest to disclose

Jay Lalezari, MD – Quest Clinical Research, San Francisco, CA Carl June, MD – University of Pennsylvania, Philadelphia, PN Pablo Tebas, MD - University of Pennsylvania, Philadelphia, PN David Stein, MD – Albert Einstein College of Medicine, Bronx, NY Ronald Mitsuyasu, MD – UCLA David Geffen School of Medicine, LA, CA

• The following individuals are employees of Sangamo BioSciences Shelley Wang, MD Gary Lee, PhD Martin Giedlin, PhD Winson Tang, MD Dale Ando, MD

Why Target CCR5 ?

• HIV (R5 virus) targets CD4 T-cell by binding to CCR5, one of the major co-receptor for HIV entry

• CCR5 delta-32 mutation produces a nonfunctional protein― Homozygotes are resistant to HIV infection ― Heterozygotes have slower disease progression

• The “Berlin Patient” is HIV-free w/o HAART for 3.5 years following hematopoietic stem cell transplant (HSC) from an allogeneic, HLA matched, CCR5 delta-32 homozygous donor

• Zinc Finger Nuclease technology enables the precise disruption of the CCR5 gene

• The therapeutic potential of CCR5 modification as seen with natural mutations and the Berlin Patient can be extended with ZFN disruption of autologous CD4+ T cells (SB-728-T) in any HIV subject

CCR5 ZFN modification

Site 165

D32 mutation

Targeting CCR5 with a ZFN

04/12/2023 5

Phase 1 SB-728-T Study Design

• Study Design: Open label, single dose studies- University of Pennsylvania/Albert Einstein College of Medicine- Quest Clinical Research/University California at Los Angeles

• Study population: Aviremic HIV subjects on HAART- Immune Responders (CD4 >450 cells/uL): n=6- Immune Nonresponders (CD4 <500 cells/uL): n=15

• Single infusion of 0.5 - 3.0 x 1010 SB-728-T • Study duration: 9-12 months• Study Endpoints

- Safety and Tolerability- Change in CD4 count and CD4/CD8 ratio- Persistence and trafficking of SB-728-T to lymphoid tissue- Change in HIV-RNA during HAART (Highly Active Antiretroviral Therapy)

treatment interruption in Immune Responders (n=6)

04/12/2023 6

Subject CharacteristicsImmune

Responders(n=6)

Immune Nonresponders

(n=15)

Age (mean + SD) 46.5 + 9.8 48.0 + 6.9

Gender 6 male 13 Male/2 Female

Ethnicity 4 Cauc/1 Asian/1 Black 8 Cauc/3 Hisp/3 Black/1 American Indian

Years HIV Infection mean median

11.8 + 10.111.8 + 9.2

17.5 + 7.218.0 + 5.1

CD4 mean median

921 + 222974 + 159

335 + 89357 + 73

CD4/CD8 mean median

1.4 + 0.61.4 + 0.5

0.7 + 0.30.7 + 0.2

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G T C A T C C T C A T C C T G A T A A A C T G C A A A A GC A G T A G G A G T A G G A C T A T T T G A C G T T T T C

SBS8267

SBS8196z

G T C A T C C T C A T C C T G A T A A A C T G C A A A A GC A G T A G G A G T A G G A C T A T T T G A C G T T T T C

SBS8267

SBS8196z

G T C A T C C T C A T C C T G A T A A A C T G C A A A A GC A G T A G G A G T A G G A C T A T T T G A C G T T T T C

SBS8267

SBS8196z

SB-728 Plasmid transfected intoAd5/35 chimeric vector

pVAX-SB-7285016 bp

KanR

BGH polyA

CMV promoterpUC ori

8267-FokEL (ZFN1)

8196z-FokKK (ZFN2)

2A peptide

Avr II (1805)

Bgl II (1739)

Eco RI (740)

Xho I (2804)

Bam HI (1145)

Bam HI (2204)

Kpn I (791)

Kpn I (1853)

ApheresisEnrich CD4+

SB-728

ExpandCryopreserve

Test cell product(SB-728-T)

Infuse

13-36% R5 disruption

SB-728-T Treatment Concept Autologous CCR5 Modified CD4+ T-cells

04/12/2023 8

SB-728-T Infusion is Safe and Well Tolerated

• Serious Adverse Events: One SAE (transfusion reaction) reported to date with a mean follow up duration of 325 days (range: 90-738 days)

• Adverse Events: 176 AEs – 120 mild severity, 55 moderate severity, 1 severe – 96 were related to study drug– 80 occurred within 24 hrs of study drug infusion and

included chills, fever, headache, hyperhidrosis, dizziness, fatigue, and abnormal garlic body odor

– No apparent relationship to dose of SB-728-T– All AEs were reversible and resolved without sequelae

04/12/2023 9

0 30 60 90 120 150 180 210 240 270 300 330 360-500

0

500

1000

1500

2000

Immune Non-Responders (N=15)

Immune Responders (N=6)

Days

Chan

ge in

CD

4 Co

unt f

rom

Bas

elin

e

Median ± SE

SB-728-T Increases CD4+ T-cell Counts

04/12/2023 10

0 30 60 90 120 150 180 210 240 270 300 330 3600.5

1.0

1.5

2.0

2.5

3.0

3.5

Immune Non-Responders (N=15)

Immune Responders (N=6)

Days

CD4:

CD8

Median ± SE

SB-728-T Normalizes CD4:CD8 T-cell Ratio in Majority of Study Subjects

04/12/2023 11

0 30 60 90 120 150 180 210 240 270 300 330 3600

10000

20000

30000

40000

50000

Immune Non-Responders (N=15)

Immune Responders (N=6)

Days

Pent

amer

Dup

licati

on p

er m

ill. C

D4

Cells

Median ± SE

SB-728-T is Detected in the Peripheral Blood for One Year and Beyond

04/12/2023 12

SB-728-T Traffics to the Rectal Mucosa

Time

Pe

rce

nt

CC

R5

Dis

rup

tio

n i

n M

uc

os

al

CD

4

0

10

20

30

40

50

60

70

N=19 N=11 N=12 N=9 N=3

Outliers

Median

Mean

75 %

25 %

Std. Error

04/12/2023 13

Asymptomatic Rectal Inflammation

0

50

100

150

200

250

Base

line

Day

14

Mon

th 3

Mon

th 6

Mon

th 1

2

Cell

Cou

nt p

er 1

0 Cr

ypts

Lymphocytes Plasma cells IEL

Time Grade* (Inflammation)

Baseline 0Day 14 0

Month 3 1.27Month 6 0.7

Month 12 0.67

6 MonthsBaseline

12 Months

SB-728-T Traffics to Rectal MucosaDuring Inflammation

04/12/2023 15

Baseline Day 14 Month 3 Month 6 Month 120

10

20

30

40

50

60

CD38/HLA-DR + CD4

CD38/HLA-DR + CD8

CCR5 Disruption in Mucosal CD4

% o

f Cel

ls

HIV-RNA Decreases during HAART Interruption in Immune Responders

04/12/2023 16

Days

0 28 56 84 112 140 168 196 224 252

Vir

al

loa

d (

Co

pie

s/m

L)

101

102

103

104

105

106

LOD

His

tori

cal

Vir

al

Se

tpo

int

(Co

pie

s/m

L)

102

103

104

105

106

PENN

201203204205 *251253

Treatment Interruption

*CCR5 - 32 Heterozygote

Dotted line denotes reinstitution of HAART

Subject 251 was excluded from the analysis due to a dual tropic HIV Infection

Estimated Biallelic CCR5 Modified T-Cells at the end of Treatment Interruption

0 5 10 15 20

Log

Vira

l Loa

d at

End

of

Tre

atm

ent I

nter

rupt

ion

(Cop

ies/

mL)

1

2

3

4

5

6

7

32 Heterozygote

rs = -0.71, P Value = <0.0001

Estimated Biallelic CCR5 Modified T-CellsDuring Treatment Interruption (% of CD4 Cells)

0 5 10 15 20

Log

Vira

l Loa

d-Ar

ea U

nder

Cur

ve

Dur

ing

Trea

tmen

t Int

erru

ptio

n (C

opie

s/m

L/Ti

me)

1

2

3

4

5

6

7

201203204205 *253

PENN

rs = -0.39, P Value = 0.036

32 Heterozygote

Control of HIV-RNA Correlates Significantly with Estimated Biallelic CCR5 Modification

04/12/2023 17

SB-728-T Summary

• Infusion of SB-728-T:– Safe and well-tolerated– Durable increases in total CD4 T-cells; normalization of CD4:CD8 ratio– Engrafts, expands, persists (>1 yr) in blood and lymphoid tissues– Traffic to lymphoid tissues during inflammation– May reduce HIV-RNA during HAART interruption in subjects with CD4 >450

cells/mm3

HIV-RNA in a Δ32 heterozygous subject became undetectable Biallelic CCR5 modification correlates with HIV-RNA suppression

04/12/2023 18

SB-728-TConclusion and Next Steps• Data from these two Phase 1 studies are promising and warrants

further evaluation

• Further clinical development of SB-728-T will aim to maximize patient exposure to CCR5 modified CD4 T-cells in two ongoing clinical trials:

– Treatment of CCR5 Δ32 heterozygous patients – Use of lymphopenic conditioning regimens to increase in vivo expansion of CCR5

modified CD4 T-cells

04/12/2023 19

SB-728-1101 Study Design• Phase 1, open-label, dose-escalation, multi-center study

• Nine subjects will be enrolled into 3 cyclophosphamide dose escalating cohorts (3 subjects/cohort) Cohort 1: Intravenous cyclophosphamide 200 mg Cohort 2: Intravenous cyclophosphamide .5 g/m2

Cohort 3: Intravenous cyclophosphamide 1.0 g/m2

A Safety Monitoring Committee will evaluate safety data and determine if it is safe to dose escalate.

• SB-728-T (0.5 to 3.0 x 1010 SB-728-T cells) will be infused one day after cyclophosphamide

• 16 week Treatment Interruption (TI) will begin 6 weeks after infusion of SB-728-T – Subjects who are aviremic and have CD4 ≥500 cells/µL

• Subjects will be followed for 12 months after the infusion

Cytoxan prior to SB-728 infusion study now open SB-728-1101 (7 sites)

• Within each cohort, treatment will be staggered so that each subsequent subject cannot be infused with Cytoxan until at least 2 weeks after the preceding subject. One day after receiving Cytoxan, subjects will be infused with SB-728-T (5 to 30 billion cells). Six weeks after SB-728-T infusion, subjects with CD4 cell counts >500 cells/mm3 will undergo a 16 week TI during which time their anti-retroviral therapy will be discontinued.

• Now we can see from cinicaltrials. gov that 18 subjects will be treated:• Estimated Enrollment: 18• Study Start Date: December 2011• Estimated Study Completion Date: December 2013• Estimated Primary Completion Date: January 2013 (Final data collection

date for primary outcome measure)• 18 people are scheduled to be treated. That should at least mean that they are

not having any safety concerns so far, one would assume. For me this is more confirming that everything is going well and they have "expanded" the trial.

Experience in Puerto Rico

• We got involved in planning to bring this study to ARC since last year in communication with Dr. Javier Morales-Ramirez (Infectious disease and AIDS Specialist from PR) and Clinical Research Puerto Rico, Inc. (CRPR).

• One patient enrolled successfully. He is a 34-years-old-male with Ht of 5’10” and Wt of 160 #. Normal labs including CBC. His prior anti-retroviral therapy includes:– Reyataz 05/27/09 – 12/20/10– Norvir 05/27/09 – 12/20/10– Truvada 05/27/09 – 12/20/10– Complera12/21/10 – to the present

• Leukapheresis done successfully by ARC Staff from Clinical Services using the Cobe Spectra machine; Collected on 07/09/12; and the procedure last 2 ½ hours. They used peripheral veins: right arm for collection and left arm for return. They processed 10,006 ml, with ACDA 16 ml, and the total volume collected and sent to Sangamo was 113 ml. Patient was hemodynamically stable all time. CRPR are waiting for the product to be infused to the patient. They have 2 possible candidates for the study under screening evaluation.

Acknowledgement by Puerto Rico Site

• Sangamo BioSciences, Inc – Donna Bednarski, Sr., CRA

• American Red Cross, Puerto Rico Region– Gladys Colon, Manager of Apheresis & Clinical Services– Maria Rodriguez, Clinical Service Supervisor and Compliance Coordinator – Rosa Vargas, Clinical Service Nurse Supervisor

• Clinical Research Puerto Rico, Inc. – Dr. Javier Morales Ramirez, Infectious Disease (PI of the Study in PR)– Helvetia Negron Gelabert, CEO– Monica Rodriguez-Melendez, Regulatory Officer

University of Pennsylvania

Albert Einstein College of MedDavid Stein, MDAngelo Seda

Carl June, MDPablo Tebas, MDGabriela Plesa, PhD

Sangamo BioSciences Dale Ando, MDWinson Tang, MDShelley Wang, MDMarty Giedlin, PhDGary Lee, PhDShirley CliftTravis WoodBaolu Chen, PhDKaye Spratt, PhDRichard Surosky, PhDMichael Holmes, PhDPhilip Gregory, PhD

Quest Clinical ResearchJay Lalezari, MDPriscila-Grace Gonzaga

University California, Los AngelesRonald Mitsuyasu, MD

University California, San FranciscoSteven Deeks, MD

National Institute of Health Sarah Read, MD, MHS Sandra Bridges, PhD Frosso Voulgaropoulou, PhD

Acknowledgements by Sangamo

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