Phase I/II Study of Retroviral-Mediated Transfer of Iduronate-2-Sulfatase Gene Into Lymphocytes of Patients With Mucopolysaccharidosis II (Mild Hunter Syndrome)

OBJECTIVES: I. Evaluate the safety and feasibility of treating mucopolysaccharidosis II (mild Hunter syndrome) by lymphocyte gene therapy.

II. Determine the levels of iduronate-2-sulfatase enzyme in these patients attained by infusing increasing doses of lymphocytes transduced with a retroviral vector designed for insertion and expression of this iduronate-2-sulfatase gene (L2SN).

III. Determine the duration of survival of these transduced cells in these patients.

IV. Determine whether monthly infusion of L2SN-transduced lymphocytes accomplishes metabolic correction (as measured by glycosaminoglycan excretion), decrease in liver or spleen volume, any therapeutic effect upon cardiac and pulmonary dysfunction, or any other effects from treatment.

Study Overview

Status

Completed

Intervention / Treatment

Detailed Description

PROTOCOL OUTLINE: Peripheral blood lymphocytes are harvested from patient by apheresis, stimulated to initiate the growth of T-lymphocytes, transduced with retrovirus L2SN containing iduronate-2-sulfatase, and reinfused into the patient.

Patients receive 12 monthly infusions of these retroviral-mediated gene transduced lymphocytes with the first three infusions in a dose escalation format.

Patients are monitored for at least 2 hours after completion of each infusion. Patients are followed at 1 year after treatment, and then until death.

Study Type

Interventional

Enrollment

2

Phase

  • Phase 2
  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Minnesota
      • Minneapolis, Minnesota, United States, 55455
        • University of Minnesota Medical School

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

PROTOCOL ENTRY CRITERIA:

--Disease Characteristics--

Mucopolysaccharidosis II (mild Hunter syndrome) as defined by the following:

  • Characteristic coarse facial features, hepatosplenomegaly, and radiographic evidence of dysostosis multiplex
  • Elevated urinary excretion of glycosaminoglycans in 3 urine specimens
  • Deficient iduronate-2-sulfatase enzyme activity as measured in plasma and leukocytes
  • Mutation consistent with mild Hunter syndrome must have either: A single base substitution of the coding sequence not previously associated with severe Hunter syndrome phenotype OR An exon-skipping mutation that would allow for occasional production of (minimal amounts of) normal protein

--Patient Characteristics--

Cardiovascular: No severe cardiac disease

Pulmonary: No severe respiratory disease

Other:

  • Must have IQ score of 80 or higher
  • Effective contraception required of all fertile patients

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Collaborators

Investigators

  • Study Chair: Chester B. Whitley, University of Minnesota

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 1996

Study Registration Dates

First Submitted

October 18, 1999

First Submitted That Met QC Criteria

October 18, 1999

First Posted (Estimate)

October 19, 1999

Study Record Updates

Last Update Posted (Estimate)

June 24, 2005

Last Update Submitted That Met QC Criteria

June 23, 2005

Last Verified

October 1, 2003

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Mucopolysaccharidosis II

Clinical Trials on lymphocyte gene therapy

3
Subscribe