Ascending Dose Study of Genome Editing by Zinc Finger Nuclease Therapeutic SB-FIX in Subjects With Severe Hemophilia B

Sangamo Therapeutics

Status and phase: Terminated; Phase 1

Conditions: Hemophilia B

Treatments: Biological: SB-FIX

Study type: Interventional

Funder types: Industry

Identifiers

NCT02695160

SB-FIX-1501

Details and patient eligibility

About

The purpose of the study is to evaluate the safety, tolerability and effect on FIX antigen and activity levels of ascending doses of SB-FIX. SB-FIX is an intravenously delivered Zinc Finger Nuclease (ZFN) Therapeutic for genome editing. It inserts a correct copy of the Factor 9 gene into the albumin locus in hepatocytes with the goal of lifelong therapeutic production of the Factor IX clotting factor.

Full description

The objective of the study is to provide long term expression of Factor IX in subjects with severe hemophilia B. SB-FIX is a therapeutic for ZFN-mediated genome editing which will be delivered by adeno-associated virus (AAV)-derived vectors. SB-FIX is intended to function by placement of a corrective copy of the Factor IX transgene into the genome of the subject's own hepatocytes, under the control of the highly expressed endogenous albumin locus, and is expected to provide permanent, liver-specific expression of Factor IX for the lifetime of a hemophilia B subject.

Enrollment: 1 patient

Sex: Male

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Male >18 years of age
• Severe hemophilia B (native circulating FIX activity <1%, with or without cross reactive material)

Exclusion criteria

• Presence of neutralizing antibodies
• History of hypersensitivity response or an allergic reaction to FIX or FIX products
• Currently receiving long acting FIX replacement therapy
• FIX mutations known to be associated with FIX inhibitors
• Polymorphisms in the ZFN target region
• Presence of any liver mass on MRI, or elevated alpha-fetoprotein (AFP)
• Any contraindication to the use of corticosteroids for immunosuppression
• Currently receiving antiviral therapy for hepatitis B or C or with history or active hepatitis B or hepatitis C or HIV-1 or HIV1/2 antibody positive.
• Chronic anemia, leukopenia, or thrombocytopenia
• Past medical history of active tuberculosis or significant fungal disease
• Symptomatic cardiovascular disease as a co-morbid condition
• Markers of hepatic inflammation or overt or occult cirrhosis
• History of chronic renal disease or creatinine ≥ 1.5 mg/dL
• Systemic (iv or oral) immunomodulatory agent or steroid use (topical treatment is allowed)
• History of chronic infection or other chronic disorder considered an unacceptable risk
• History of malignancy except for treated basal cell or squamous cell carcinoma
• History of alcohol or substance abuse
• Previously received gene therapy product
• Participation in prior investigational drug or medical device study within the previous 3 months
• History of therapeutic non-adherence
• Any other reason that, in the opinion of the Investigator or Medical Monitor, would render the subject unsuitable for participation in the study

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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1 participants in 3 patient groups

Cohort 1

Experimental group

Description:

SB-FIX: Low Dose

Treatment:

Biological: SB-FIX

Cohort 2

Experimental group

Description:

SB-FIX: Medium Dose

Treatment:

Biological: SB-FIX

Cohort 3

Experimental group

Description:

SB-FIX: High Dose

Treatment:

Biological: SB-FIX