An Open-Label Phase 1/2 Study to Assess the Safety, Efficacy and Dose of Study Drug UX003 Recombinant Human Beta-glucuronidase (rhGUS) Enzyme Replacement Therapy in Patients With Mucopolysaccharidosis Type 7 (MPS 7)

Ultragenyx

Status and phase: Completed; Phase 2; Phase 1

Conditions: Mucopolysaccharidosis Type 7

Treatments: Drug: UX003

Study type: Interventional

Funder types: Industry

Identifiers

NCT01856218

UX003-CL201

Details and patient eligibility

About

UX003-CL201 is an open-label Phase 1/2 study to assess the safety, efficacy, and dose of UX003 in MPS 7 patients via intravenous (IV) administration every other week (QOW) for 36 weeks with up to an additional 36 weeks from the optional continuation period. Up to 5 participants, who are between 5 and 30 years of age inclusive, will be enrolled and treated with UX003.

The initial 12-week treatment period will be followed by a 24-week forced dose titration period to assess the optimal dose. Participants who complete both the initial treatment and forced dose titration periods will continue treatment in a 36- week continuation period.

Enrollment: 3 patients

Sex: All

Ages: 5 to 30 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Confirmed diagnosis of MPS 7 based on leukocyte or fibroblast glucuronidase enzyme assay or genetic testing confirming diagnosis.
• Elevated urinary glycosaminoglycan (uGAG) excretion at a minimum of 2-fold over normal.
• Between 5 and 30 years of age, inclusive (approximately 2 subjects between the ages of 20-30 years).
• Willing and able to provide written, signed informed consent, or in the case of subjects under the age of 18 (or 16 years, depending on the region), provide written assent (if required) and written informed consent by a legally authorized representative after the nature of the study has been explained, and prior to any research-related procedures.
• Sexually active subjects must be willing to use an acceptable method of contraception while participating in the study.
• Females of childbearing potential must have a negative pregnancy test at Screening and be willing to have additional pregnancy tests during the study. Females considered not of childbearing potential include those who have had tubal ligation at least one year prior to Screening, or who have had total hysterectomy.

Exclusion criteria

• Has undergone a successful bone marrow or stem cell transplant or has any degree of detectable chimaerism with donor cells.
• Any known hypersensitivity to rhGUS or its excipients that, in the judgment of the Investigator, places the subject at increased risk for adverse effects.
• Pregnant or breastfeeding at Screening or planning to become pregnant (self or partner) at any time during the study.
• Use of any investigational product (drug or device or combination) within 30 days prior to Screening, or requirement for any investigational agent prior to completion of all scheduled study assessments at any time during the study.
• Has a condition of such severity and acuity, in the opinion of the Investigator, that it warrants immediate surgical intervention or other treatment or may not allow safe study participation.
• Has a concurrent disease or condition that, in the view of the Investigator, places the subject at high risk of poor treatment compliance or of not completing the study, or would interfere with study participation or affect safety.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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3 participants in 1 patient group

UX003

Experimental group

Description:

During the initial 14-week treatment period of the study, participants receive 2 mg/kg UX003 every other week (QOW) for 12 weeks. At Week 14, participants continue on UX003 therapy and begin a forced dose titration period for an additional 24 weeks at the dose sequence of 1, 4, and 2 mg/kg UX003 QOW as follows: 1 mg/kg UX003 for 8 weeks beginning on Week 14; then 4 mg/kg UX003 for 8 weeks beginning on Week 22; then 2 mg/kg UX003 for 8 weeks beginning on Week 30. Following the 24 week forced dose titration period, participants who continue on treatment (continuation period) received 2 mg/kg UX003 QOW beginning at Week 38 for up to an additional 36 weeks. After the first phase of the study, participants who elect to continue drug treatment are transitioned to the long-term extension phase, where they are treated with UX003 at 4 mg/kg beginning at Week 74, for up to an additional 168 weeks.

Treatment:

Drug: UX003