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Extension of Study TKT024 Evaluating Long-Term Safety and Clinical Outcomes in MPS II Patients Receiving Idursulfase

Phase 2
Completed
Conditions
Mucopolysaccharidosis II (MPS II)
Hunter Syndrome
Interventions
Biological: Idursulfase
Registration Number
NCT00630747
Lead Sponsor
Shire
Brief Summary

Study TKT024EXT was a long-term, single-arm, open-label extension of Study TKT024, a one year Phase 2/Phase 3 registration study. The primary objective of this extension study was to collect long-term safety and clinical outcome data in Mucopolysaccharidosis II (MPS II), also known as Hunter Syndrome, from the Phase 2/Phase 3 Study TKT024. All patients enrolling into this study received weekly active treatment with idursulfase, the primary dosing regimen investigated in Study TKT024.

Hunter Syndrome is an X-linked recessive lysosomal storage disease caused by a deficiency of iduronate-2-sulfatase, an enzyme required to catabolize glycosaminoglycans (GAGS) in cells. As a result, GAGs accumulate in the lysosomes leading to cellular engorgement, organomegaly, tissue destruction, and organ system dysfunction. Hunter Syndrome is a rare disease with an estimated incidence of 1 in 162,000 live births.

Detailed Description

Study TKT024EXT was conducted in 2 phases. The first phase ("Phase I") was 2 years (104 weeks) in duration and consisted of weekly infusions of IV idursulfase (0.5 mg/kg), and the collection of patients' safety and clinical outcomes. Week 105 defined the beginning of the second phase of the study. The second phase ("Phase II") consisted of weekly infusions of IV idursulfase (0.5 mg/kg) and the monitoring of patients for safety (via collection of adverse events, concomitant medications, and vital signs). Study completion was defined as the time a patient either transitioned to commercially available idursulfase or discontinued this study.

Idursulfase was administered to patients as a continuous IV infusion at a dose of 0.5 mg of protein per kg of body weight (0.5 mg/kg). Final evaluations from Study TKT024, the one-year predecessor Phase 2/Phase 3 registration study, served as the baseline assessments for the TKT024EXT study. Forced vital capacity (FVC) and the 6-minute walk test (6MWT) continued to be the primary clinical outcomes of TKT024EXT study. Efficacy outcomes were evaluated over the course of 2 years and were determined at 4-month intervals during the first year (ie, Weeks 18, 36, and 53) and at 6-month intervals in the second year (ie, Weeks 79 and 105). Safety outcomes were assessed throughout the duration of the study. The safety and clinical testing performed in the TKT024EXT study were identical to those performed in the double-blind phase of Study TKT024.

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
94
Inclusion Criteria
  • Patient must have completed the double-blind phase of Study TKT024, defined as completing the Week 53 final evaluations.
  • Patient, patient's parent(s), or legally authorized representative must have voluntarily signed an Institutional Review Board (IRB)/Independent Ethics Committee (IEC)-approved informed consent form after all relevant aspects of the study have been explained and discussed with the patient.
Exclusion Criteria
  • Patient has received treatment with an investigational therapy other than iduronate-2-sulfatase in Study TKT024 within the past 60 days.
  • Patient is unable to comply with the protocol (e.g., due to a medical condition such as cervical cord compression or uncooperative attitude) or is unlikely to complete the study, as determined by the investigator.
  • Patient has experienced an adverse reaction to study drug in Study TKT024, which contraindicates further treatment with idursulfase.
  • Patient with known hypersensitivity to any of the components of idursulfase.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
IdursulfaseIdursulfase-
Primary Outcome Measures
NameTimeMethod
Change From Baseline in Mean Percent Predicted Forced Vital Capacity (FVC) at Week 105Baseline and at Week 105

Determined by spirometry. The change is calculated as Week 105 minus baseline.

Change From Baseline in Mean Distance Walked in the 6-minute Walk Test (6MWT) at Week 105Baseline and at Week 105

Determined on a walking course. The change was calculated as Week 105 minus baseline.

Secondary Outcome Measures
NameTimeMethod
Change From Baseline in Mean Combined Liver and Spleen Volume at Week 105Baseline and at Week 105

Determined by Magnetic Resonance Imaging (MRI). The change was calculated as Week 105 minus baseline.

Change From Baseline in Mean Normalized Urine Glycosaminoglycans (GAG) Levels at Week 105Baseline and at Week 105

Determined by urine testing. The change was calculated as Week 105 minus baseline.

Change From Baseline in Mean Passive Joint Range of Motion (JROM) at Week 105Baseline and at Week 105

Change was calculated as Week 105 minus baseline. Global JROM (% normal range of motion) is the average of 11 ratios multiplied by 100. Ratios are Left/Right means of passive range of motion in Shoulder (Flexion/Extension, Abduction, Internal/External Rotation), Elbow (Flexion/Extension), Wrist (Flexion/Extension), Index Finger (Flexion/Extension \[Combined Metacarpophalangeal joint (MCP), Proximal interphalangeal joint (PIP), Distal interphalangeal joint (DIP) motion\]), Hip (Flexion/Extension, Abduction, Internal/External Rotation), Knee (Flexion/Extension), and Ankle (Dorsiflexion) divided by the normal range (American Academy of Orthopedic Surgeons and American Medical Association).

Change From Baseline in Mean Cardiac Left Ventricular Mass Index (LVMI) at Week 105Baseline and at Week 105

Determined by echocardiogram. LVMI indexed to body surface area (g/m\^2). The change was calculated as Week 105 minus baseline.

Trial Locations

Locations (52)

Pediatric Clinical Research Center, Children's Hospital Oakland

🇺🇸

Oakland, California, United States

Harbin Clinic

🇺🇸

Rome, Georgia, United States

Children's Hospital Boston

🇺🇸

Boston, Massachusetts, United States

Mid-Illinois Hematology and Oncology Associates

🇺🇸

Normal, Illinois, United States

University of Iowa Hospitals and Clinics

🇺🇸

Iowa City, Iowa, United States

Saint Louis University Cardinal Glennon Children's Hospital

🇺🇸

Saint Louis, Missouri, United States

Upstate Medical University, State University of New York (SUNY)

🇺🇸

Syracuse, New York, United States

Children's Hospital of Philadelphia

🇺🇸

Philadelphia, Pennsylvania, United States

University of North Carolina at Chapel Hill

🇺🇸

Chapel Hill, North Carolina, United States

Franciscan Skemp Healthcare

🇺🇸

La Crosse, Wisconsin, United States

Fundacao Universidade de Ciencias da Saude de Alagoas Governador Lamenha Filho / UNCISAL

🇧🇷

Maceio, AL, Brazil

Clinica Casa de Saude Sao Joao

🇧🇷

Barreiras, BA, Brazil

c-HUPES/UFBA

🇧🇷

Salvador, BA, Brazil

Hospital Universitario da Faculdade de Medicina da Universidade Federal de Mato Grosso do Sul

🇧🇷

Campo Grande, MS, Brazil

Instituto de Puericultura e Pediatria Martagao Gesteira / Hospital Pediatrico

🇧🇷

Rio de Janeiro, RJ, Brazil

Hospital de Clinicas de Porto Alegre, Servico de Genetica Medica

🇧🇷

Porto Alegre, RS, Brazil

UNIFESP Instituto de Oncologia Pediatrica

🇧🇷

Sao Paulo, SP, Brazil

Instituto da Crianca / Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo

🇧🇷

Sao Paulo, SP, Brazil

Hopital Edouard Herriot

🇫🇷

Lyon, France

The Hospital for Sick Children Research Institute

🇨🇦

Toronto, Ontario, Canada

University of Montreal / Hopital Ste-Justine

🇨🇦

Montreal, Quebec, Canada

Hopital de Hautepierre

🇫🇷

Strasbourg Cedex, France

Hospital Ducuing

🇫🇷

Toulouse Cedex, France

Universitatsklinikum Aachen Kinderklinik

🇩🇪

Aachen, Germany

Universitatsklinik Dusseldorf Kinderklinik

🇩🇪

Dusseldorf, Germany

Justus-Liebig Universitat

🇩🇪

Giessen, Germany

Children's University Hospital Mainz AG

🇩🇪

Mainz, Germany

Universitatsklinikum Gottingen

🇩🇪

Gottingen, Germany

Universitatsklinikum Hamburg Eppendorf

🇩🇪

Hamburg, Germany

Universita degli Studi di Napoli Federico II

🇮🇹

Napoli, Italy

Universita di Padova

🇮🇹

Padova, Italy

Universita Milano Bicocca / Ospedale S. Gerardo

🇮🇹

Milan, Italy

Ospedale S. S. Annunziata

🇮🇹

Savigliano, Italy

Spitalul Clinic de Copii

🇷🇴

Cluj Napoca, Cluj, Romania

Servicio de Pediatria

🇪🇸

Linares, Jaen, Spain

University Hospital Germans Trias i Pujol

🇪🇸

Badalona, Spain

Drottning Silvias Barnsjukhus

🇸🇪

Gothenberg, Sweden

Karolinska University Hospital

🇸🇪

Stockholm, Sweden

Bath and NE Somerset Primary Care Trust

🇬🇧

Bath, United Kingdom

Addenbrooke's Hospital

🇬🇧

Cambridge, United Kingdom

Great Ormond Street Hospital for Sick Children

🇬🇧

London, United Kingdom

Royal Hospital for Sick Children

🇬🇧

Glasgow, United Kingdom

Derbyshire Children's Hospital

🇬🇧

Derby, United Kingdom

Royal Manchester Children's Hospital

🇬🇧

Manchester, United Kingdom

Royal Victoria Infirmary

🇬🇧

Newcastle, United Kingdom

Royal Surrey County Hospital

🇬🇧

Guildford, Surrey, United Kingdom

St. Joseph's Hospital

🇺🇸

Phoenix, Arizona, United States

The Children's Hospital

🇺🇸

Denver, Colorado, United States

Comprehensive Cancer Centers of Nevada

🇺🇸

Las Vegas, Nevada, United States

Baylor College of Medicine Texas Children's Hospital

🇺🇸

Houston, Texas, United States

University of Utah Hospital

🇺🇸

Salt Lake City, Utah, United States

University of Nebraska Medical Center

🇺🇸

Omaha, Nebraska, United States

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