The U.S. Food and Drug Administration (FDA) has granted orphan drug designation to TG Therapeutics‘ investigational oral therapy umbralisib for the treatment of follicular lymphoma (FL).
The status, which follows another orphan drug designation granted by the FDA last year for all three types of marginal zone lymphoma (MZL) – nodal, extranodal, and splenic – provides the company with various incentives. These include assistance in developing trial protocols and a seven-year period of market exclusivity if the treatment earns final regulatory approved.
Earlier this year, the company initiated a rolling submission of a New Drug Application (NDA) to the FDA, asking for umbralisib’s accelerated approval for both MZL and FL. That came on the heels of a breakthrough therapy designation for MZL patients. The submission is expected to be completed in the first quarter of 2020.
“The receipt of orphan drug designation for umbralisib to treat patients with FL is another important milestone in the development and anticipated commercialization of umbralisib in MZL and FL,” Michael S. Weiss, executive chairman and CEO of TG Therapeutics, said in a press release.
Previously known as TGR-1202, umbralisib is a once-daily oral therapy that works on two fronts. It blocks the PI3K delta protein, which is involved in a number of processes in both healthy and cancer cells, but primarily in the signaling, development, and survival of immune B-cells. By binding it, umbralisib prevents the uncontrolled growth and survival of B-cell tumors, without affecting the normal functioning of other PI3K proteins.
The therapy also inhibits CK1-epsilon, a protein involved in key processes related to tumor development and progression. Blocking CK1-epsilon is also thought to tamper down the immune-related adverse events associated with previous PI3K inhibitors.
Umbralisib has demonstrated anti-cancer activity in preclinical models of blood cancers, as well as in clinical studies, TG Therapeutics says on its website.
The ongoing, open-label UNITY-NHL Phase 2b trial (NCT02793583) is evaluating umbralisib, alone or in combination with other drugs, for treating non-Hodgkin’s lymphomas like MZL and FL. The trial is still recruiting participants at locations worldwide.
The FL group in this trial is seeking to determine the therapy’s effectiveness and safety in people with follicular lymphoma who have undergone treatment with at least two lines of therapy, including an anti-CD20 regimen and an alkylating agent.
The main goal is to assess the proportion of patients who respond to treatment, and secondary measures include safety, duration of response, and time lived without disease worsening.
Findings from the first 118 FL patients included in the trial showed that more than 40% had a positive response — partial or complete — to the treatment, meeting the primary goal for that group of participants.
The preliminary data for the first 42 people with MZL receiving umbralisib as a single agent also showed that more than half (52%) responded to the treatment.
“We were pleased to announce last year that both the MZL and FL cohorts of the UNITY-NHL trial met their primary endpoints and have commenced our first rolling submission for these indications,” Weiss said. “We are excited by the progress so far and look forward to completion of this [NDA] submission targeted in the first half of this year.”
