TG Therapeutics’ B-cell Therapy Could Allow for Rapid Dosing, Early Data Suggest

Early data from TG Therapeutics’ Phase 2 trial of its B-cell-targeting experimental multiple sclerosis (MS) treatment ublituximab (TG-1101), showed that the drug is well-tolerated and effectively reduces B-cells in the blood.

MS therapies that deplete B-cells have been effective in relapsing and progressive forms of MS. Like other B-cell-targeting drugs in development, TG’s treatment is an antibody that binds to the CD20 molecule on B-cell surfaces.

TG said it is done recruiting for the first part of the trial (NCT02738775), which focuses on patients with relapsing MS. The treatment has been tested in three patient groups with different infusion times.

The groups, consisting of eight patients each, received an initial 600 mg dose of ublituximab in two infusions: 150 mg on day 1 and 450 mg on day 15. The treatment was followed by either 450 mg or 600 mg at week 24. The latter doses were administered at accelerated times, down to an hour in the third group.

The goal was to reach the one-hour infusion time, which the company plans to use in its Phase 3 trial.

Results showed that all three groups had a median reduction of B-cells of 99%, and there were no grade 3 or 4 side effects during the study.

“We were extremely pleased to see rapid and robust B-cell depletion and excited to see that a one-hour infusion was well tolerated, possibly providing an important convenience advantage over first-generation anti-CD20 monoclonal antibodies,” Michael S. Weiss, the company’s executive chairman and CEO said in a press release.

“Recent data shows that B-cell depletion therapy may be amongst the most efficacious new weapons to fight MS. The speed at which we were able to rapidly enroll into this study demonstrates the on-going need for new treatment options for patients.” Weiss added. “We look forward to continuing enrollment into one or more expansion cohorts and to launching a Phase 3 program in the first half of this year.”

“Given the favorable safety profile, and unique ability for TG-1101 to be dosed in a rapid 1-hour infusion, we are excited to continue to enroll into this study and participate in the Phase 3 program,” said Edward Fox, MD, PhD, director of the Multiple Sclerosis Clinic of Central Texas and clinical assistant professor at the University of Texas Medical Branch in Round Rock, Texas.

Currently, Roche’s Ocrevus (ocrelizumab) is leading the race for market approval among B-cell therapies for MS. Ocrevus is expected to be approved for relapsing and progressive forms of MS this spring.