Abstract Details

Ublituximab, a novel glycoengineered monoclonal antibody, targets a unique epitope of CD20. Ublituximab provided significantly improved efficacy vs teriflunomide in ULTIMATE I and II.  

To further characterize time course and severity of IRRs with ublituximab.

ULTIMATE I (N=549) and II (N=545) evaluated ublituximab 450 mg intravenous 1-hour infusion every 24 weeks (following Day 1 infusion of 150 mg and Day 15 infusion of 450 mg) or teriflunomide 14 mg oral once daily for 96 weeks in patients with RMS. The teriflunomide group received placebo infusions; the ublituximab group received oral placebo. Participants received antihistamine and corticosteroid premedication 30-60 minutes prior to ublituximab/placebo infusions. Pooled IRR data from both trials were analyzed.

Across ULTIMATE studies, the total number of infusions was 2644 (ublituximab) and 2637 (placebo). IRR rates were 47.7% (ublituximab) and 12.2% (placebo). 43.3% of ublituximab-treated patients had an IRR at the first infusion. 67.7% (n=176) had 1 IRR only; of these, 93.2% experienced the IRR at first dose. In patients experiencing >1 IRR (n=84), 85.7% experienced the first IRR during the first dose; thus, among patients with a first-dose IRR, 69.5% did not have an IRR recurrence. Pyrexia was the most common IRR (9.5% of ublituximab-treated patients). One patient experienced a Grade 4 IRR (anaphylaxis) with ublituximab at the Day 15 infusion (drug interrupted/withdrawn) following two Grade 1 IRRs at the first infusion (both reported as influenza-like syndrome); all IRRs resolved. Data on IRR incidence in ublituximab patients receiving oral, intravenous, intramuscular, and mixed oral/intravenous/intramuscular premedication will be presented. Overall, 96.6% of total ublituximab infusions were completed without interruption.

IRRs were the prevailing adverse event with ublituximab in ULTIMATE I and II; the majority occurred at the first dose and had minimal impact on infusion completion, and pyrexia was the most common.