This is a single treatment arm study that is open-label to be conducted in Chinese participants with MPS I.

Trial Objectives are to evaluate the safety and tolerability of Aldurazyme in Chinese MPS I participants, and to evaluate the efficacy of Aldurazyme on the percent change of urinary glycosaminoglycans (uGAGs) from baseline to Week 26. The study will also evaluate the effect on uGAG level and liver volume (hepatomegaly) after 26 weeks, with Aldurazyme treatment in Chinese MPS I participants.

Treatment duration will include: 2 weeks of screening, 26 weeks of treatment and 1 week of follow-up period. During the treatment period, weekly visits are designed to accommodate weekly administration of Aldurazyme (laronidase).

Study duration for each participant will be a total of 29 weeks which will include 2 weeks of screening, 26 weeks of treatment period and 1 week of follow-up period.

Inclusion Criteria:

• Chinese participants have a documented diagnosis of MPS I confirmed by measurable clinical signs and symptoms of MPS I and fibroblast or leukocyte IDUA (iduronidase) activity <10% of normal.

• Participants have to be able to stand independently and walk a minimum of 5 meters in 6 minutes.

• A female participant is eligible to participate if she is not pregnant or breastfeeding, and at least one of the following conditions applies:

  • Is not a woman of childbearing potential (WOCBP).
  • OR
  • Is a WOCBP and agrees to use an acceptable contraceptive method during the intervention period and at a minimum until 7 days after the last dose of study intervention.
  • A WOCBP must have a negative highly sensitive pregnancy test (urine or serum as required by local regulations) within the screening period before the first dose of study intervention.
  • If a urine test cannot be confirmed as negative (eg, an ambiguous result), a serum pregnancy test is required. In such cases, the participant must be excluded from participation if the serum pregnancy result is positive.
  • Contraceptive/barrier method is not applicable for male participants.

Exclusion Criteria:

• Prior tracheostomy or bone marrow transplantation or hematopoietic stem cell transplantation.
• Have a plan to undergo bone marrow transplantation or hematopoietic stem cell transplantation within half a year after enrollment.
• Received an investigational drug, or device, other than Aldurazyme, within 30 days prior to study enrollment.
• Received an investigational gene therapy.

The above information is not intended to contain all considerations relevant to a potential participation in a clinical trial.

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org