Five Years of Ublituximab in Multiple Sclerosis: ULTIMATE I and II Open-Label Extension Study.
Publication Title
JAMA Neurol
Document Type
Article
Publication Date
2-16-2026
Keywords
washington; seattle; swedish
Abstract
Importance: In the 2-year Study to Assess the Efficacy and Safety of Ublituximab in Participants With Relapsing Forms of Multiple Sclerosis (ULTIMATE) I and II randomized clinical studies, disease activity was significantly reduced with ublituximab vs teriflunomide in participants with relapsing multiple sclerosis (RMS).
Objective: To evaluate long-term ublituximab clinical efficacy and safety.
Design, setting, and participants: The 2-year, multicenter, randomized, active-controlled, double-blind period (DBP) of the ULTIMATE I and II phase 3 studies occurred September 2017 to November 2020. Enrollment in the ongoing ULTIMATE open-label extension (OLE) study began November 2019; data cutoff for this analysis was January 1, 2024.
Intervention: ULTIMATE OLE participants continued ublituximab (UBL-UBL) or switched from teriflunomide to ublituximab (TER-UBL).
Main outcomes and measures: Efficacy (annualized relapse rate [ARR], 24-week confirmed disability progression [CDP24], and 24-week confirmed disability improvement [CDI24]) and safety were key outcomes.
Results: Of 985 adults with RMS who completed ULTIMATE I and II, 851 enrolled in the ULTIMATE OLE and were included in the analysis. On DBP completion, more than 85% of participants (UBL-UBL, 422 of 494; TER-UBL, 429 of 491) entered the OLE, of whom more than 70% (UBL-UBL, 297 of 422; TER-UBL, 327 of 429) continued taking ublituximab at year 5 (OLE year 3) at data cutoff, making up the analysis population (mean [SD] age, 38.5 [9.7] years; 532 female [62.5%]). TER-UBL participants experienced a 58.4% ARR reduction at 1 year after the switch (0.182 vs 0.076; rate ratio, 0.42; 95% CI, 0.29-0.60; P < .001), and ARR continued to decrease to 0.048 (year 4) and 0.045 (year 5). UBL-UBL participants had further ARR reductions after the DBP (0.053, 0.032, and 0.020 for years 3, 4, and 5, respectively). At year 5, CDP24 was 8.0% in UBL-UBL participants vs 14.3% in TER-UBL participants (P = .01), and CDI24 was 17.0% in UBL-UBL participants vs 12.2% in TER-UBL participants (P = .02). Adverse events were consistent with the established safety profile from pivotal trials, with exposure-adjusted incidence rates per 100 participant-years of serious infections (excluding COVID events) of 2.10 (UBL-UBL) and 2.58 (TER-UBL). On average, immunoglobulin levels remained above the lower limit of normal, and no significant differences in serious infection rates were observed regardless of immunoglobulin level.
Conclusions and relevance: Results reveal that sustained clinical benefits were observed with 5 years of ublituximab treatment: ARR in year 5 showed 1 relapse per 50 participant-years of ublituximab treatment and 92% of UBL-UBL participants remained free from CDP24. Results confirm long-term ublituximab benefits and early initiation of high-efficacy treatment.
Trial registration: ClinicalTrials.gov Identifier: NCT04130997.
Area of Special Interest
Neurosciences (Brain & Spine)
Specialty/Research Institute
Neurosciences
DOI
10.1001/jamaneurol.2026.0007
