TG wraps up orphan tags for both its clinical candidates


TG Therapeutics ($TGTX) got orphan drug designation from the FDA for both its clinical candidates this week. It’s aiming for approvals in these niche indications--as well as in bigger markets for hematological malignancies and autoimmune disorders.

It has secured the orphan tag for both its TG-1101 (ublituximab), a glycoengineered anti-CD20 monoclonal antibody, to treat neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorder (NMOSD) and its TGR-1202, an oral, next-gen PI3K Delta inhibitor, to treat with chronic lymphocytic leukemia (CLL).

"NMO is closely related to multiple sclerosis, an area of significant interest to us,” said the company’s CEO Michael Weiss in a statement. “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."

It’s looking for a larger market with TG-1101 in autoimmune disease multiple sclerosis (MS). The company plans to advance TG-1101 into pivotal testing in MS during the first half of next year.

The B cell malignancy and autoimmune disease small cap is ultimately aiming to combine TG-1101 with approved CLL agent Imbruvica (ibrutinib), as well as with its with its own TGR-1202 to treat CLL and diffuse large B-cell lymphoma (DLBCL).

Discussing the GENUINE Phase III trial of TG-1101 in combination with ibrutinib in high-risk CLL, Weiss said on the company’s most recent earnings call, “We've launched this study with the hope and intention that this will be a fast andstraightforward approach to getting TG-1101 approved. Recall, at the time we designed this study, we were very uncertain of what the FDA would require to get two novel drugs approved simultaneously.”

He continued, “We still believe that GENUINE's goal of improving on ibrutinib therapy represents an important treatment goal. There is no question that ibruitinib is a very good drug but few if any patients are cured with single agent ibruitinib. Our Phase II study demonstrated increases in overall response as well as a deepening of responses with 25% of the patients on the combination of ibrutinib plus TG-1101 obtaining either a complete response and/or MRD (minimal residual disease) negativity.”

Wall Street is bidding its time waiting for more data; TG Therapeutics’ market cap is only about $350 million. Despite its tiny valuation, the company has some pretty major biotech investors including Fidelity Management, RA Capital Management and Baker Brothers Advisors.