Final MRI Results At 6 Months From A Phase 2 Multicenter Study Of Ublituximab, A Novel Glycoengineered Anti-CD20 Monoclonal Antibody (mAb), In Patients With Relapsing Forms Of Multiple Sclerosis (RMS), Demonstrates Complete Elimination Of Gd-Enhancing Lesions (P3.409)

Objective: To examine the effect of ublituximab on the development of new gadolinium (Gd) enhancing lesions, T2 lesions and T1 hypointense volume at Week 24 in RMS subjects. Background: Focal inflammatory lesions underlie the occurrence of relapses in MS, and demyelinating axons are more susceptible to neurodegeneration. Treatment with antiCD20 mAbs have shown significant reduction in MRI and clinical disease activity in RMS patients. Ublituximab is a novel, chimeric mAb which targets a unique epitope on the CD20 antigen and is glycoengineered to enhance affinity for all variants of FcγRIIIa receptors, demonstrating greater antibody dependent cellular cytotoxicity activity than rituximab. Design/Methods: TG1101-RMS201 is a 52-week, Phase 2, placebo-controlled, multicenter study that is designed to assess the safety and optimal infusion of ublituximab in RMS subjects. All subjects, including placebo (post-placebo phase), receive 3 ublituximab infusions on Days 1, 15, and Week 24. Number of new Gd-enhancing lesions, T2 lesion volume, and T1 hypointense lesion volume are evaluated on brain MRI scans performed at baseline, Week 24 (pre-dose) and Week 48. Results: To date, MRI data has been analyzed up to Week 24 in 31 patients, encompassing two ublituximab infusions, data expected on 48 subjects at time of presentation. At baseline, there was a total number of 73 T1 Gd-enhancing lesions (mean 2.4±4.0). At Week 24, total number of T1 Gd-enhancing lesions were reduced to 0 (p= 0.003). Further, T2 lesion volume decreased 8.1% (p=0.01) from baseline to Week 24. The mean T1 hypointense lesions volume decreased 6.6% (p=0.04) from baseline to Week 24. Conclusions: Ublituximab is well tolerated and 6-month data shows potent B-cell depletion and robust efficacy on MRI endpoints. Additionally, infusion times as low as one hour and lower dose infusions, relative to other anti-CD20’s, provide a convenience benefit for patients. Study Supported by: TG Therapeutics, Inc. Disclosure: Dr. Inglese has nothing to disclose. Dr. Petracca has nothing to disclose. Dr. Cocozza has nothing to disclose. Dr. Wray has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Acorda, Bayer, Biogen, EMD Serono, Genzyme, Novartis, Questcor, Receptos, Genentech/Roche, Teva. Dr. Racke has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Coherus Bioscience;Teva Neuroscience;. Dr. Shubin has received research support from TG Therapeutics, Inc. Dr. Twyman has received research support from TG Therapeutics, Inc. Dr. Su has nothing to disclose. Dr. Eubanks has nothing to disclose. Dr. Mok has nothing to disclose. Dr. Weiss has nothing to disclose. Dr. Fox has nothing to disclose.