A Clinical Pharmacological Study of MT-3921 in Subjects With Human T-cell Leukemia Virus Type 1 (HTLV-1)-Associated Myelopathy (HAM)
The purposes of this study is to assess the safety, tolerability, and pharmacokinetics of MT-3921 in subjects with Human T-cell Leukemia Virus Type 1 (HTLV-1)-Associated Myelopathy(HAM). Subjects meeting eligibility criteria will enter the 6-month double-blind period. Subjects will be randomized in a 2:1 ratio to receive MT-3921 or placebo in a double blind manner.
⁃ Additional screening criteria check may apply for qualification:
• Subjects aged 20 years or older on the day of consent
• Subjects with a confirmed diagnosis of HAM according to the diagnostic algorithm of Practical Guideline for HAM 2019 on the day of consent
• Subjects with an Osame's motor disability score (OMDS) of ≥4 and ≤6 at Screening and on the first day of the Treatment period (predose)
• Subjects with no change in OMDS for at least 3 months before the day of consent
• Subjects with a CSF concentration neopterin of ≥6 pmol/mL at Screening
• Subjects on maintenance oral steroid therapy who have continued to receive the same dose equivalent to ≤10 mg/day of prednisolone for at least 3 months before the day of consent