AVROBIO : ASGCT Cystinosis Update May 2023

ASGCT 2023 cystinosis update

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ASGCT 2023 cystinosis update

Summary of key points

Continued positive trends across multiple biomarkers and neurocognitive measures seen in Phase 1/2 collaborator-sponsored trial

All patients remain off oral cysteamine, up to 36 months post-gene therapy

Safety and tolerability profile remains strong

Positive interactions with U.K. Medicines and Healthcare products Regulatory Agency (MHRA) and U.S. Food and Drug Administration (FDA) in Q1 2023

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Cystinosis Phase 1/2 dosing complete

Phase 1/2

Objectives

• Safety and tolerability
• Hypothesis generation
  of clinical efficacy endpoints

Collaborator-sponsored

University of California, San Diego

Patients

• 6 patients
• Adults and adolescents
• Cohorts 1-2 >18 years; Cohort 3 >14 years
• Male and female
• Oral and ophthalmic cysteamine

Clinical trial funded in part by grants to UCSD from the California Institute for Regenerative Medicine (CIRM), Cystinosis Research Foundation (CRF) and National Institutes of Health (NIH)	4

VCN trending as expected, indicating sustained engraftment

Drug Product VCN/dg

Patient 1	2.1
Patient 2	1.3
Patient 3	1.6
Patient 4	0.6
Patient 5	2.5
Patient 6	2.9*

CYSTINOSIS PHASE 1/2: PATIENTS 1-6

NEW DATA POINT

PBC	3.5
3.0
-
Genome	2.5
	2.0
Diploid	1.5
1.0
VCN/	0.5
0.0

o

o

o

o

o

o

o

o

o

o

o

o

o

1m

3m

6m

9m

2m

5m

8m

1m

4m

7m

0m

3m

6m

1

1

1

2

2

2

3

3

3

VCN: Vector Copy Number; PBCs: Peripheral Blood Cells; dg: Diploid Genome

*Average of 2 drug products5 Note: Patient 2 was lost to follow-up after 12 months