TG Therapeutics’ Potential Neuromyelitis Optica Treatment Named Orphan Drug by FDA

The U.S. Food and Drug Administration (FDA) has designated TG-1101 (ublituximab), a glycoengineered anti-CD20 monoclonal antibody by TG Therapeutics, an orphan drug to advance its development. The drug is a potential treatment for neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorder (NMOSD), two relapsing-remitting autoimmune diseases with similarities to multiple sclerosis.

Currently, there are no FDA-approved treatments for these disorders.

“We are pleased to announce our first orphan drug designation for TG-1101 in a non-oncology indication, providing additional proprietary protection for TG-1101,” Michael S. Weiss, executive chairman and interim CEO of TG Therapeutics, said in a press release.

“NMO is closely related to Multiple Sclerosis, an area of significant interest to us. We look forward to presenting early data from our current Phase 1b study of TG-1101 in NMO at the ECTRIMS (European Committee for the Treatment and Research in Multiple Sclerosis) conference this September, which we believe will provide an early peek into the effects of TG-1101 in patients with autoimmune diseases,” Weiss added.

An orphan drug designation offers special status to a drug or biological product that is intended for the effective and safe prevention, diagnosis, or treatment of a rare disease or condition that affects less than 200,000 people in the United States. It qualifies the treatment’s sponsor for various development incentives, including tax credits for qualified clinical testing.

NMOSD is a recently proposed unifying term for neuromyelitis optica — also known as Devic’s disease — and its related syndromes. It is a relapsing inflammatory demyelinating disease that most commonly affects optic nerves and the spinal cord, leading to sudden vision loss or weakness in one or both eyes, and a loss of sensation and bladder function.

During a relapse, new damage to the optic nerves and/or spinal cord can lead to accumulating disability, as in MS. Unlike MS, however, there is no progressive phase in this disorder, so that preventing attacks is a critical treatment approach. NMO is estimated to affect about five in every 100,000 people.

TG Therapeutics is also assessing TG-1101 in patients with relapsing-remitting MS (RRMS) in a Phase 2 clinical trial (NCT02738775) in the U.S. that is currently recruiting patients.