Safety, Pharmacokinetics, and Pharmacodynamics/Efficacy of SBC-103 in Mucopolysaccharidosis III, Type B (MPS IIIB)

Alexion Pharmaceuticals

Status and phase: Completed; Phase 2; Phase 1

Conditions: Mucopolysaccharidosis IIIB

Treatments: Drug: SBC-103

Study type: Interventional

Funder types: Industry

Identifiers

NCT02324049

NGLU-CL02

Details and patient eligibility

About

Study to evaluate the safety and tolerability of intravenous (IV) administration of SBC-103 in participants with mucopolysaccharidosis III, type B (MPS IIIB, Sanfilippo B) with evaluable signs or symptoms of developmental delay.

Full description

This study was designed as a 3-part study to evaluate the safety and tolerability of IV administration of SBC-103. Participants enrolled in Part A (0.3, 1.0, or 3.0 milligrams [mg] per kilogram [kg] of SBC-103 administered every other week [QOW] for 24 consecutive weeks). Participants who completed Part A were eligible for Part B (an increase to 1.0 or 3.0 mg/kg QOW). Participants who completed Part B were eligible for Part C (5.0 and/or 10.0 mg/kg to continue through Week156; no participants received both 5.0 and 10.0 mg/kg). Due to the early termination of the SBC-103 development program, including this study, all participants withdrew from Part C at the sponsor's decision. As a result of the early termination of this program, this report provides only safety data.

Enrollment: 11 patients

Sex: All

Ages: 2 to 12 years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

Key Inclusion Criteria:

• A participant was greater than or equal to 2 years of age but less than 12 years of age at the time of informed consent.
• Definitive diagnosis of MPS IIIB.
• Documented developmental delay.

Key Exclusion Criteria:

• Received treatment with gene therapy at any time.
• Previous hematopoietic stem cell or bone marrow transplant.
• Had any internal or non-removable external metal items that presented a safety risk for study assessments that utilized magnetic fields, or any other medical condition or circumstance in which magnetic resonance imaging was contraindicated according to local institutional policy.
• Known hypersensitivity to eggs.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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11 participants in 1 patient group

SBC-103

Experimental group

Description:

Part A (Initial therapy): Participants received SBC-103, 0.3, 1.0, or 3.0 mg/kg QOW for 24 weeks, followed by a ≥ 4-week treatment break. Participants enrolled in the lowest dosage first. Part B: Participants were escalated to the next highest dose that was considered safe (1.0 or 3.0 mg/kg QOW) for ≥ 8 weeks. Participants who received doses of 0.3 mg/kg in Part A were considered for a second dose escalation to 3.0 mg/kg at any time during Part B provided that they tolerated at least 2 doses of 1.0 mg/kg in Part B. Participants who received and tolerated at least 4 doses of SBC-103 QOW at 3.0 mg/kg were considered for participation in Part C. Part C: Participants received SBC-103 5.0 or 10.0 mg/kg administered IV QOW. Dosing in Part C began at the 5.0 mg/kg dose level. The decision to begin dosing the first participant at 10.0 mg/kg was based on the review of safety data at 5.0 mg/kg.

Treatment:

Drug: SBC-103