HIV study using genetic engineering and apheresis.

1. 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, MD
Medical Director
Puerto Rico Region, Biomedical Services
American Red Cross
For the ARC Medical Directors
Meeting Sept. 12, 2012

2. 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

3. 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

4. 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

5. Targeting CCR5 with a ZFN
D32 mutation
CCR5
ZFN modification
Site 165
9/10/2012 5

6. 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)
9/10/2012 6

7. Subject Characteristics
Immune Immune
Responders Nonresponders
(n=6) (n=15)
Age (mean + SD) 46.5 + 9.8 48.0 + 6.9
Gender 6 male 13 Male/2 Female
8 Cauc/3 Hisp/3 Black/
Ethnicity 4 Cauc/1 Asian/1 Black
1 American Indian
Years HIV Infection
mean 11.8 + 10.1 17.5 + 7.2
median 11.8 + 9.2 18.0 + 5.1
CD4
mean 921 + 222 335 + 89
median 974 + 159 357 + 73
CD4/CD8
mean 1.4 + 0.6 0.7 + 0.3
median 1.4 + 0.5 0.7 + 0.2
9/10/2012 7

8. SB-728-T Treatment Concept
Autologous CCR5 Modified CD4+ T-cells
SBS8196z pUCori CMV promoter
Eco RI (740)
KpnI (791)
Bam HI (1145)
pVAX-SB-728
8267-FokEL (ZFN1)
5016 bp
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 G KanR
C 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
Bgl II (1739)
2A peptide
BGH polyA Avr II (1805)
Xho I (2804) KpnI (1853)
Bam HI (2204)
SB-728
SBS8267 8196z-FokKK (ZFN2) Plasmid transfected into
Ad5/35 chimeric vector
SB-728
Enrich
Apheresis CD4+ Infuse
Expand
13-36% Cryopreserve
R5 disruption Test cell product
(SB-728-T)
9/10/2012 8

9. 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
9/10/2012 9

10. SB-728-T Increases CD4+ T-cell Counts
2000
Change in CD4 Count from Baseline
1500 Immune Non-Responders (N=15)
Immune Responders (N=6)
1000
Median ± SE
500
0
-500
0 30 60 90 120 150 180 210 240 270 300 330 360
Days
9/10/2012 10

11. SB-728-T Normalizes CD4:CD8 T-cell Ratio in
Majority of Study Subjects
3.5
Immune Non-Responders (N=15)
3.0
Immune Responders (N=6)
2.5
CD4:CD8
Median ± SE
2.0
1.5
1.0
0.5
0 30 60 90 120 150 180 210 240 270 300 330 360
Days
9/10/2012 11

12. SB-728-T is Detected in the Peripheral Blood
for One Year and Beyond
50000
Pentamer Duplication per mill. CD4 Cells
40000 Immune Non-Responders (N=15)
Immune Responders (N=6)
30000
Median ± SE
20000
10000
0
0 30 60 90 120 150 180 210 240 270 300 330 360
Days
9/10/2012 12

13. SB-728-T Traffics to the Rectal Mucosa
70
Percent CCR5 Disruption in Mucosal CD4
60 Outliers
50
75 %
Mean
40
Median
30 25 %
Std. Error
20
10
0
N=19 N=11 N=12 N=9 N=3
li ne ks ks ks ks
se ee ee ee ee
W W W W
Ba 2-
3 12 24 48
6- 16- 36-
Time
9/10/2012 13

14. Asymptomatic Rectal Inflammation
Baseline 6 Months
Lymphocytes Plasma cells IEL
250 Grade*
Time
(Inflammation)
Cell Count per 10 Crypts
200 Baseline 0
Day 14 0
Month 3 1.27
150
Month 6 0.7
Month 12 0.67
100
50
0
Month 12
Month 3
Month 6
Baseline
Day 14
12 Months

15. SB-728-T Traffics to Rectal Mucosa
During Inflammation
60
CD38/HLA-DR + CD4
50
CD38/HLA-DR + CD8
CCR5 Disruption in Mucosal CD4
40
% of Cells
30
20
10
0
Baseline Day 14 Month 3 Month 6 Month 12
9/10/2012 15

16. HIV-RNA Decreases during HAART
Interruption in Immune Responders
106 106
Treatment Interruption PENN
201
Historical Viral Setpoint (Copies/mL)
10 5 203 105
204
205 *
Viral load (Copies/mL)
251
253
104 104
103 103
102 102
LOD
*CCR5 - 32 Heterozygote
101
0 28 56 84 112 140 168 196 224 252
Days
Dotted line denotes reinstitution of HAART
9/10/2012 16

17. Control of HIV-RNA Correlates Significantly
with Estimated Biallelic CCR5 Modification
During Treatment Interruption (Copies/mL/Time)
7 7
Treatment Interruption (Copies/mL)
rs = -0.39, P Value = 0.036
Log Viral Load-Area Under Curve
6 6
Log Viral Load at End of
5 5 32 Heterozygote
PENN
4 4 201
rs = -0.71, P Value = <0.0001
203
204
3 3
205 *
253
2 2
32 Heterozygote
1 1
0 5 10 15 20 0 5 10 15 20
Estimated Biallelic CCR5 Modified T-Cells Estimated Biallelic CCR5 Modified T-Cells
at the end of Treatment Interruption During Treatment Interruption (% of CD4 Cells)
 Subject 251 was excluded from the analysis due to a dual tropic HIV
Infection
9/10/2012 17

18. 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
9/10/2012 18

19. SB-728-T
Conclusion 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
9/10/2012 19

20. 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

21. 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.

22. 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
– Complera 12/21/10 – 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.

23. 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

24. Acknowledgements by Sangamo
University of Pennsylvania Sangamo BioSciences
Carl June, MD Dale Ando, MD
Pablo Tebas, MD Winson Tang, MD
Gabriela Plesa, PhD Shelley Wang, MD
Marty Giedlin, PhD
Albert Einstein College of Med Gary Lee, PhD
David Stein, MD Shirley Clift
Angelo Seda Travis Wood
University California, Los Angeles Baolu Chen, PhD
Kaye Spratt, PhD
Ronald Mitsuyasu, MD Richard Surosky, PhD
University California, San Francisco Michael Holmes, PhD
Steven Deeks, MD Philip Gregory, PhD
National Institute of Health Quest Clinical Research
Sarah Read, MD, MHS Jay Lalezari, MD
Sandra Bridges, PhD Priscila-Grace Gonzaga
Frosso Voulgaropoulou, PhD
9/10/2012 24