Phase I/II, open label, multicenter, multinational (Japan, Brazil and the US) extension study of JR-171-101 (NCT04227600) for the treatment of MPS I

Patients who have completed the Part2 of JR-171-101 study (NCT04227600) and fulfill all eligibility criteria can be enrolled in this JR-171-102 study. In the JR-171-102 study, subjects will receive either 2.0 or 4.0 mg/kg/week of JR-171 intravenously at the same doses received at Week 12 of the JR-171-101 study.

Inclusion Criteria:

• Patients who have completed the Part 2 of JR-171-101 study
• A patient from whom written informed consent can be obtained. If the patient is aged under 18 years (20 years in case of Japan) at the time of assent or willingness to participate in the study cannot be confirmed due to MPS I-related intellectual disability, informed permission from the patient's legally acceptable representative (e.g., his/her parents or guardians) need to be obtained instead of his/her consent. Even in this case, written informed consent should be obtained from the patient, wherever possible
• Female patient or male patient whose co-partners is of child-bearing potential agree to use a medically accepted, highly effective method of contraception, such as spermatocidal gel plus condom, an intrauterine device or oral contraceptives until one month after the final administration.

Exclusion Criteria:

• A patient who is unable to perform the study procedures, except for 6-minute walk test, neurocognitive testing, BVMT-R, HVLT-R, and T.O.V.A.
• Judged by the principal investigator or subinvestigator as being unable to undergo lumbar puncture, including those who have difficulties in taking a position for lumbar puncture due to joint contracture or those who are likely to experience difficulty breathing during the lumbar puncture process
• Judged by the principal investigator or subinvestigator to be ineligible to participate in the study due to a history of a serious drug allergy or hypersensitivity to any drugs
• Otherwise judged by the principal investigator or subinvestigator to be ineligible to participate in the study in consideration of patient's safety