An Open-label, Multi-center, Phase I/II Study to Assess Safety, Disease Progression, and Cellular Kinetics Following YTB323 Administration in Participants With Non-active Progressive Multiple Sclerosis (PMS)
This is an open-label, multi-center, non-confirmatory study to assess the safety, disease progression, and cellular kinetics following YTB323 administration to 28 participants with non-active Progressive Multiple Sclerosis (PMS). The study design utilizes an ascending single dose design consisting of 3 sentinel cohorts followed by an expansion cohort.
• Male or female participants 18 to 60 years (inclusive) at screening.
• Signed informed consent must be obtained prior to participation in the study.
• Able to communicate well with the investigator, to understand and comply with the requirements of the study including:
‣ Able to undergo lumbar puncture (LP), blood draws, tolerate brain and spinal MRI, and able to participate and tolerate all study procedures at study visits.
• Diagnosis of SPMS or PPMS according to the 2017 McDonald diagnostic criteria (Thompson et al 2018) as confirmed at screening visit.
• Less than 15 years (inclusive) from onset of first MS symptoms as determined by the investigator during screening.
• Ambulatory Patients (EDSS 3 to 6.5 inclusive) at screening.
• Evidence of recent (within 24 months) disease progression of ≥1.00 on the EDSS scale.
• No relapse in the last 24 months at screening.
• No Gd-enhancing lesion on brain or spinal cord MRI at screening.
⁃ Participants must receive or be current on all recommended vaccinations according to institutional, local, or global guidelines for immunocompromised patients at least 6 weeks prior to lymphodepletion.