A Phase 1/2 interventional study of rapcabtagene autoleucel (YTB323) in Relapsing Multiple Sclerosis, sponsored by Novartis Pharmaceuticals. Active, not recruiting at 18 sites in 6 countries. Open to participants aged 18 Years to 60 Years. Per ClinicalTrials.gov, last updated 2026-09-02.
Sponsored by Novartis Pharmaceuticals · Phase 1/2, Interventional, and Treatment
This is an open-label, multi-center, non-confirmatory study to assess the safety, efficacy, and cellular kinetics of YTB323 in approximately 28 participants with Relapsing Multiple Sclerosis (RMS) with breakthrough disease activity during previous treatment with a highly efficacious therapy (BD-HET). The study design utilizes an ascending single dose design consisting of 3 sentinel cohorts followed by an expansion cohort.
All participants in this study will receive YTB323. Both the participant and the study doctor will know the participant is getting YTB323. Participants will be given one dose of YTB323. Different groups of participants may receive a higher dose of YTB323, if proven to be safe for every participant at the lower dose. Participants are in this study for 2 years and will be followed for an additional 13 years in a long-term follow up study. The main question this trial is designed to answer: Is YTB323 treatment safe for participants with relapsing MS?
3,460 studies on the registry are indexed under Multiple Sclerosis; 661 are open to participants now.
This study's planned enrollment of 28 is below the median of 50 across 2,342 interventional studies indexed under Multiple Sclerosis.
Browse Multiple Sclerosis studies →Novartis Pharmaceuticals is the lead sponsor of 2,673 studies on the registry; 228 are open to participants now.
Of its 576 completed or terminated interventional studies of FDA-regulated products, 431 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Evidence of breakthrough disease activity is defined as one or more of the following:
Persistent radiological activity defined by one of the following:
≥2 new T2 lesions compared to a previous scan within a period ≤1 year
Exclusion Criteria:
Any contraindications to LP, including but not limited to:
Other protocol-defined inclusion/exclusion criteria may apply
Participants will receive one dose of YTB323
Biological: rapcabtagene autoleucel (YTB323)
Participants will receive one dose of YTB323
Biological: rapcabtagene autoleucel (YTB323)
Participants will receive one dose of YTB323
Biological: rapcabtagene autoleucel (YTB323)
Participants will receive one dose of YTB323
Biological: rapcabtagene autoleucel (YTB323)
CAR-T cell suspension for intravenous infusion
Number of participants with Adverse Events (AEs) and Serious Adverse Events (SAEs)
Incidence of dose limiting toxicities (DLTs), AEs and SAEs, including changes in vital signs, electrocardiograms (ECGs), laboratory parameters, neurological status and magnetic resonance (MRI) of the brain and spinal cord qualifying and reported as AEs.
Time frame: Day 1 through Year 2
Measure of Disability: Expanded Disability Status Scale (EDSS).
EDSS is used to measure the change in disability level in participants using a scale from 0 to 10. The higher the score, the greater the degree of disability.
Time frame: Day 1 through Year 2
Measure of Disability: Short Form Health Survey (SF-36 v2)
The Short Form Health Survey (SF-36 v2) is a widely used and extensively studied instrument to measure health-related quality of life among healthy participants and participants with acute and chronic conditions. It consists of eight subscales that can be scored individually: Physical Functioning, Role-Physical, Bodily Pain, General Health, Vitality, Social Functioning, Role-Emotional, and Mental Health. Two overall summary scores, the Physical Component Summary (PCS) and the Mental Component Summary (MCS) also can be computed. The SF 36 has proven useful in monitoring general and specific populations, comparing the relative burden of different diseases, differentiating the health benefits produced by different treatments, and in screening individual participants.
Time frame: Day 1 through Year 2
Measure of Disability: Timed 25 Foot Walk (T25FW)
The T25FW is a mobility test based on a timed walk of 25 feet that is administered by a trained administrator. The participant is directed to walk the clearly marked 25-foot distance as quickly as possible. Longer completion time corresponds with decreased mobility.
Time frame: Day 1 through Year 2
Measure of Disability: 9 Hole Peg Test (9HPT)
The 9HPT is a finger dexterity test that is administered by a trained administrator. The participant is directed to put 9 pegs, one by one, onto and then off the holder board as quickly as possible starting with using only the dominant hand, and then repeated with the non-dominant hand. Longer completion times are associated with decreased finger dexterity.
Time frame: Day 1 through Year 2
Measure of Disability: Symbol Digit Modalities Test (SDMT)
The SDMT is a timed cognition test administered by a trained administrator. The test assesses sustained attention, processing speed, visual scanning, and motor speed to determine cognitive impairment. Participants are given a coding key which contains abstract symbols that correspond to specific numbers. Participants are timed how quickly and accurately they are able to substitute the symbols for the numbers and is scored by the number of correctly coded items.
Time frame: Day 1 through Year 2
Measure of Disability: Fatigue Symptoms and Impacts Questionnaire - Relapsing Multiple Sclerosis (FSIQ-RMS)
The FSIQ-RMS is a questionnaire to assess fatigue-related symptoms in patients with RMS. Participants will indicate the severity of fatigue experienced for each question that examines different aspects of fatigue.
Time frame: Day 1 through Year 2
Number of new and enlarging T2 lesions and Gd-enhancing T1 Lesions
Measured in the brain by Magnetic Residence Imaging (MRI)
Time frame: Day 1 through Year 2
Plasma Pharmacokinetics (PK) of YTB323 - CMAX
Measured by Cmax - The maximum plasma concentration of YTB323
Time frame: Day 1 through Year 2
Plasma Pharmacokinetics (PK) of YTB323 - AUC
Measured by AUC - Area under the curve of YTB323
Time frame: Day 1 through Year 2
Plasma Pharmacokinetics (PK) of YTB323 - Tmax
Measured by Tmax - Time to Reach the Maximum Concentration After Drug Administration of YTB323
Time frame: Day 1 through Year 2
Plasma Pharmacokinetics (PK) of YTB323 - Clast
Clast is defined as the Last observed (quantifiable) plasma concentration (Clast)
Time frame: Day 1 through Year 2
Plasma Pharmacokinetics (PK) of YTB323 - Tlast
Tlast is defined as Time of Last Measurable Concentration
Time frame: Day 1 through Year 2
Safety data including dose limiting toxicities (DLTs), Adverse Events (AEs), and Serious Adverse Events (SAEs) from each dose level
Safety data from each dose level will be used to assess safe dose-level(s) to be continued in phase 2 and later clinical studies
Time frame: Day 1 through Year 2
Humoral Immunogenicity of YTB323
Incidence and prevalence of pre-existing and treatment induced humoral immunogenicity of YTB323
Time frame: Day 1 through Year 2
Cellular Immunogenicity of YTB323
Incidence and prevalence of pre-existing and treatment induced cellular immunogenicity of YTB323
Time frame: Day 1 through Year 2
Plan to share: Yes — Novartis is committed to sharing with qualified external researchers, access to patient-level data and supporting clinical documents from eligible studies. These requests are reviewed and approved by an independent expert panel on the basis of scientific merit. All data provided is anonymized to respect the privacy of patients who have participated in the trial in line with applicable laws and regulations. This trial data is currently available according to the process described on www.clinicalstudydatarequest.com
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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