About the STARLIGHT Study

The STARLIGHT Study is a Phase 3 clinical research study to evaluate an investigational drug (a drug not yet approved for clinical use) to see if it is safe and whether it may improve behavioral and cognitive function in children with Hunter syndrome, also known as MPS II. The study will compare the effects of the investigational drug to the current standard-of-care treatment.

Study participants will be assigned to 1 of 2 groups—Group A or Group B—for a study duration of 12 or 24 months.

Approximately 80 participants will be enrolled, and they will be reimbursed for travel and certain study-related expenses.

Study participants who qualify and meet all eligibility criteria will receive either the investigational drug or the standard-of-care treatment, which is enzyme replacement therapy (known commercially as Elaprase®), through weekly IV infusions (through a vein). The probability of receiving the investigational drug or the standard-of-care treatment is 50/50. This is an open-label study, and both the researchers and participants will know which study treatment is being administered. Participants will also undergo a variety of tests and procedures during the study, such as blood and image tests, cognitive testing, and lumbar punctures.

Study participants assigned to the standard-of-care group may be eligible to switch to the investigational drug during the study if certain clinical criteria are met.

Participants may also be eligible to join a long-term extension study, which provides an opportunity for participants to receive the investigational drug for a longer period.