Dose-Ranging Study of ST-920, an AAV2/6 Human Alpha Galactosidase A Gene Therapy in Subjects With Fabry Disease (STAAR)

NCT04046224 | Completed Phase 1 Results DMC FDA Drug

• 1 other identifier: ST-920-201
• Study Type: interventional
• Target: 36
• Locations: 7 countries
• Sites: 18

Brief Summary

This is the first in human treatment with ST-920, an adeno-associated virus (AAV2/6) vector encoding the complementary deoxyribonucleic acid (cDNA) for human a-Gal A. The purpose of this study is to evaluate the safety and tolerability of ascending doses of ST-920. ST-920 aims to provide stable, long-term production of α-Gal A at therapeutic levels in subjects with Fabry disease. The constant production of α-Gal A in humans should, importantly, enable reduction and potentially clearance of Fabry disease substrates Gb3 and lyso-Gb3. On Day 1, patients will be infused intravenously with a single dose of ST-920 and followed for a period of 52 weeks.

Conditions

Fabry Disease

Keywords

Sangamo; Rare; Lysosomal Storage Disease; Gene Therapy

Outcome Measures

Primary Outcomes (4)

• Incidence of Treatment-emergent Adverse Events (TEAEs) - All

  All incidences of Treatment-Emergent Adverse Events (TEAEs) in subjects who receive ST-920 as assessed by Common Terminology Criteria for Adverse Events (CTCAE)

  Up to 12 months after the ST-920 infusion

• Incidence of Treatment-emergent Adverse Events (TEAEs) - Related to ST-920

  Incidences of Treatment-Emergent Adverse Events (TEAEs) directly related to ST-920 in subjects who receive ST-920 as assessed by Common Terminology Criteria for Adverse Events (CTCAE)

  Up to 12 months post ST-920 infusion

• Incidence of Treatment-emergent Adverse Events (TEAEs) - Serious

  All incidences of serious Treatment-Emergent Adverse Events (TEAEs) in subjects who receive ST-920 as assessed by Common Terminology Criteria for Adverse Events (CTCAE)

  Up to 12 month post ST-920 infusion

• Incidence of Treatment-emergent Adverse Events (TEAEs) - Any TEAEs Leading to Study Discontinuation or Withdrawal

  All incidences of Treatment-Emergent Adverse Events (TEAEs) that lead to study discontinuation or withdrawal in subjects who receive ST-920 as assessed by Common Terminology Criteria for Adverse Events (CTCAE)

  Up to 12 month post ST-920 infusion

Secondary Outcomes (1)

• To Assess Alpha Gal-A Activity in Plasma Over Time

  up to 12 months post ST-920 infusion

Study Arms (2)

Sequential dose escalation

EXPERIMENTAL

ST-920 is administered as a single infusion: 1. Cohort 1: 0.5e13 vg/kg 2. Cohort 2: 1.0e13 vg/kg 3. Cohort 3: 3.0e13 vg/kg 4. Cohort 4: 5.0e13 vg/kg

Biological: ST-920

Expansion Cohorts

EXPERIMENTAL

1. Anti Alpha-Gal A Antibody Positive Cohort 2. Anti Alpha-Gal A Antibody Negative Cohort 3. Female Cohort 4. Renal Cohort 5. Cardiac Cohort

Biological: ST-920

Interventions

ST-920 BIOLOGICAL

Single dose of investigational product ST-920

Expansion Cohorts; Sequential dose escalation

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• ≥ 18 years of age
• Documented diagnosis of Fabry disease
• One or more of the following symptoms: i) cornea verticillata, ii) acroparesthesia, iii) anhidrosis, iv) angiokeratoma
• Subject must be fully vaccinated (as per the Centers for Disease Control and Prevention (CDC) definition in the US and as per local guidelines in other countries) for Coronavirus Disease (COVID-19) at least one month prior to dosing
• Renal Cohort:
• Screening estimated glomerular filtration rate (eGFR) value between 40-90 mL/min/1.73 m²
• Linear negative eGFR slope (estimated from at least 3 serum creatinine values within 18 months, including the value obtained during screening visit) of ≥ 2 mL/min/1.73m²/year
• Cardiac Cohort:
• Left ventricular hypertrophy (LVH) in 2D echocardiography or cardiac magnetic resonance imaging (CMR) defined as an end diastolic septum and posterior wall thickness ≥12 mm with no other explanation for LVH, OR presentation with cardiac changes indicative of disease progression such as decreased global longitudinal strain on 2D strain echocardiography or low native T1 mapping on CMR

You may not qualify if:

• Neutralizing antibodies to AAV6
• eGFR \< 40 ml/min/1.73m2
• New York Heart Association Class III or higher
• Active infection with hepatitis A, B or C, human immunodeficiency virus (HIV) or tuberculosis (TB)
• History of liver disease such as clinically significant steatosis, fibrosis, non-alcoholic steatohepatitis (NASH) and cirrhosis, biliary disease within 6 months of informed consent; except for Gilbert's syndrome
• Elevated circulating serum alpha fetoprotein (AFP)
• Recent or recurrent hypersensitivity response to enzyme replacement therapy (ERT) within within 6 months prior to consent
• Current or history of systemic (IV or oral) immunomodulatory agents, or biologics or steroid use in the past 6 months prior to consent (topical treatment and inhaled allowed).
• Contraindication to use of corticosteroids
• History of malignancy except for non-melanoma skin cancer and localized prostate cancer treated with curative intent
• Recent history of alcohol or substance abuse
• Participation in investigational interventional drug or medical device study throughout the duration of this study and within previous 3 months prior to consent
• Prior treatment with a gene therapy product
• Known hypersensitivity to components of ST-920 formulation
• Any other reason that, in the opinion of the Site Investigator or Medical Monitor, would render the subject unsuitable for participation in the study including but not limited to risk of COVID-19 infection

Sponsors & Collaborators

• Sangamo Therapeutics: lead

Study Sites (18)

University of California, Irvine

Irvine, California, 92697, United States

Location

University of South Florida

Tampa, Florida, 33620, United States

Location

Emory University School of Medicine

Atlanta, Georgia, 30322, United States

Location

Ann & Robert H. Lurie Children's Hospital of Chicago

Chicago, Illinois, 60611, United States

Location

University of Iowa Hospital and Clinics

Iowa City, Iowa, 52242, United States

Location

University of Minnesota Medical Center

Minneapolis, Minnesota, 55455, United States

Location

Mt. Sinai School of Medicine

New York, New York, 10029, United States

Location

Cincinnati Children's Hospital Medical Center

Cincinnati, Ohio, 45229, United States

Location

Lysosomal and Rare Disorders Research and Treatment Center (LDRTC)

Fairfax, Virginia, 22030, United States

Location

The Royal Melbourne Hospital

Parkville, Victoria, 3050, Australia

Location

M.A.G.I.C. Clinic Ltd.

Calgary, Alberta, T2E 7Z4, Canada

Location

University Medical Center Hamburg-Eppendorf

Hamburg, Germany

Location

University Hospital of Würzburg

Würzburg, Germany

Location

Azienda Ospedaliero-Universitaria Careggi

Florence, Tuscany, 50134, Italy

Location

National Taiwan University Hospital

Taipei, Taiwan

Location

Queen Elizabeth Hospital

Birmingham, B15 2TH, United Kingdom

Location

Addenbrooke's Hospital

Cambridge, CB2 0QQ, United Kingdom

Location

Royal Free Hospital

London, United Kingdom

Location

MeSH Terms

Conditions

Fabry Disease; Lysosomal Storage Diseases

Condition Hierarchy (Ancestors)

Sphingolipidoses; Lysosomal Storage Diseases, Nervous System; Brain Diseases, Metabolic, Inborn; Brain Diseases, Metabolic; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Cerebral Small Vessel Diseases; Cerebrovascular Disorders; Vascular Diseases; Cardiovascular Diseases; Genetic Diseases, X-Linked; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Metabolism, Inborn Errors; Lipidoses; Lipid Metabolism, Inborn Errors; Metabolic Diseases; Nutritional and Metabolic Diseases; Lipid Metabolism Disorders

Results Point of Contact

• Title: Michael Chen
• Organization: Sangamo Therapeutics, Inc.

mchen@sangamo.com

(628) 252-4079

Study Officials

• Medical Monitor

  Sangamo Therapeutics, Inc.

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: LTE60
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SEQUENTIAL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 1, 2019
• First Posted: August 6, 2019
• Study Start: July 23, 2019
• Primary Completion: April 10, 2025
• Study Completion: April 10, 2025
• Last Updated: April 14, 2026
• Results First Posted: April 14, 2026

Record last verified: 2026-04

Locations

US (9); IT (1); AU (1); CA (1); DE (2); TW (1); GB (3)