TG Therapeutics Announces Data from a Phase 1 Study Evaluating TG-1701 as a Monotherapy and as a Triple Combination with Ublituximab and UKONIQ® at the 2021 American Society of Clinical Oncology Annual Meeting

Rhea-AI Summary

TG Therapeutics (TGTX) reported promising clinical data for its investigational oral BTK inhibitor, TG-1701, presented at the ASCO Annual Meeting. The monotherapy showed a 100% overall response rate (ORR) in patients with chronic lymphocytic leukemia (CLL) at 300 mg QD (n=19). The triple combination therapy with ublituximab and UKONIQ (U2) yielded a 79% ORR and a 21% complete response (CR) rate. The safety profile was generally tolerable, with early signs of complete responses in the combination therapy. TG Therapeutics aims to continue enrollment and present more data.

Positive

• 100% ORR in CLL patients treated with 300 mg QD of TG-1701 monotherapy (n=19).
• 79% ORR with a 21% CR rate in the triple combination of Ublituximab and UKONIQ (U2) + TG-1701 (n=19).
• Overall response rates of 95% in CLL and Waldenstrom macroglobulinemia (WM) for the 200 mg QD monotherapy cohort.

Negative

• Grade 3 adverse events occurred in 10% or more of patients treated with U2 + TG-1701, including diarrhea (11%) and ALT/AST increases (16%).
• Serious adverse reactions reported in 18% of patients receiving UKONIQ, impacting the treatment outlook.

100% ORR in CLL patients treated with 300 mg QD of TG-1701 monotherapy (n=19)

Triple combination of ublituximab and UKONIQ (U2) + TG-1701 cohort (n=19) resulted in 79% ORR, with 21% CR rate, including 100% ORR in patients WM, CLL, MZL, MCL, and DLBCL (n=11)

NEW YORK, June 04, 2021 (GLOBE NEWSWIRE) -- TG Therapeutics, Inc. (NASDAQ: TGTX), today announced data from TG-1701, the Company’s investigational once-daily, oral BTK inhibitor, as a monotherapy and as a triple therapy in combination with ublituximab, the Company’s novel glycoengineered anti-CD20 monoclonal antibody, and UKONIQ^® (umbralisib), the Company’s once-daily, inhibitor of PI3K-delta and CK1-epsilon in patients with front line or relapsed/refractory non-Hodgkin’s lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Data from this trial were made available on demand this morning during the American Society of Clinical Oncology (ASCO) Annual Meeting. Presentation highlights are included below.

Michael S. Weiss, the Company’s Executive Chairman and Chief Executive Officer, stated, “We are pleased to see that with additional patients and longer follow-up, TG-1701, our BTK inhibitor, continues to show encouraging clinical activity paired with what appears to be a tolerable safety profile, especially in the triple combination with U2. It is also exciting to see some early complete responses in patients treated with the triple therapy. We look forward to continuing to enroll on this trial and presenting additional data.”

PRESENTATION HIGHLIGHTS:

Poster Presentation Title:  TG-1701, A Selective Bruton Tyrosine Kinase (BTK) Inhibitor, as Monotherapy and in Combination with Ublituximab and Umbralisib (U2) in Chronic Lymphocytic Leukemia (CLL) and Lymphoma

• A total of 125 patients with R/R CLL or B-cell lymphoma have been treated with TG-1701, with patients receiving monotherapy in the dose-escalation cohort (n=25), 200 mg in a dose-expansion cohort (n=61), 300 mg in a CLL dose-expansion cohort (n=20), or TG-1701 in combination with U2 in the dose escalation cohort (n=19).
• TG-1701 monotherapy was well tolerated and the maximum tolerated dose was not reached up to 400 mg QD.
• Adverse Events (AEs) of special interest in patients treated with 200 mg and 300 mg QD of TG-1701 (n=81), included Grade 3 hypertension (4.9%), atrial fibrillation (1.2%), and no instances of major bleeding observed. Grade 3 AEs occurring in ≥10% of patients treated with U2+1701 included diarrhea (11%), neutropenia (11%), ALT increase (16%), and AST increase (16%), and Grade 4 AEs occurring in ≥10% of patients treated with U2+1701 included neutropenia (11%).
• At a median follow up of 12.2 months in the 200 mg QD monotherapy expansion cohorts, overall response rates (ORR) were: 95% (19/20) in CLL, 65% (13/20) in mantle cell lymphoma (MCL), and 95% (19/20) in Waldenstrom macroglobulinemia (WM).
• 100% ORR observed at a median follow up of 8.6 months in the 300 mg CLL monotherapy cohort (n=19).
• At a median follow up of 15.6 months, the 1701+U2 dose escalation (using doses of 100mg to 300 mg QD of TG-1701) resulted in 79% ORR, with 21% CR rate across patients with WM, CLL, marginal zone lymphoma (MZL), diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) (n=19).

Data presented at ASCO 2021 is available on the Publications page of the Company’s website at https://www.tgtherapeutics.com/publications/.


ABOUT TG THERAPEUTICS, INC.
TG Therapeutics is a fully-integrated, commercial stage biopharmaceutical company focused on the acquisition, development and commercialization of novel treatments for B-cell malignancies and autoimmune diseases. In addition to an active research pipeline including five investigational medicines across these therapeutic areas, TG has received accelerated approval from the U.S. FDA for UKONIQ^® (umbralisib), for the treatment of adult patients with relapsed/refractory marginal zone lymphoma who have received at least one prior anti-CD20-based regimen and relapsed/refractory follicular lymphoma who have received at least three prior lines of systemic therapies. Currently, the Company has three programs in Phase 3 development for the treatment of patients with relapsing forms of multiple sclerosis (RMS) and patients with chronic lymphocytic leukemia (CLL) and several investigational medicines in Phase 1 clinical development. For more information, visit www.tgtherapeutics.com, and follow us on Twitter @TGTherapeutics and Linkedin.

UKONIQ^® is a registered trademark of TG Therapeutics, Inc.

ABOUT UKONIQ^® (umbralisib)
UKONIQ is the first and only oral inhibitor of phosphoinositide 3 kinase (PI3K) delta and casein kinase 1 (CK1) epsilon. PI3K-delta is known to play an important role in supporting cell proliferation and survival, cell differentiation, intercellular trafficking and immunity and is expressed in both normal and malignant B-cells. CK1-epsilon is a regulator of oncoprotein translation and has been implicated in the pathogenesis of cancer cells, including lymphoid malignancies. 

UKONIQ is indicated for the treatment of adult patients with relapsed or refractory marginal zone lymphoma (MZL) who have received at least one prior anti-CD20-based regimen and for the treatment of adult patients with relapsed or refractory follicular lymphoma (FL) who have received at least three prior lines of systemic therapy.

These indications are approved under accelerated approval based on overall response rate. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

IMPORTANT SAFETY INFORMATION
Infections: Serious, including fatal, infections occurred in patients treated with UKONIQ. Grade 3 or higher infections occurred in 10% of 335 patients, with fatal infections occurring in <1% . The most frequent Grade ≥3 infections included pneumonia, sepsis, and urinary tract infection. Provide prophylaxis for Pneumocystis jirovecii pneumonia (PJP) and consider prophylactic antivirals during treatment with UKONIQ to prevent CMV infection, including CMV reactivation. Monitor for any new or worsening signs and symptoms of infection, including suspected PJP or CMV, during treatment with UKONIQ. For Grade 3 or 4 infection, withhold UKONIQ until infection has resolved. Resume UKONIQ at the same or a reduced dose. Withhold UKONIQ in patients with suspected PJP of any grade and permanently discontinue in patients with confirmed PJP. For clinical CMV infection or viremia, withhold UKONIQ until infection or viremia resolves. If UKONIQ is resumed, administer the same or reduced dose and monitor patients for CMV reactivation by PCR or antigen test at least monthly.

Neutropenia: Serious neutropenia occurred in patients treated with UKONIQ. Grade 3 neutropenia developed in 9% of 335 patients and Grade 4 neutropenia developed in 9%. Monitor neutrophil counts at least every 2 weeks for the first 2 months of UKONIQ and at least weekly in patients with neutrophil count <1 x 10⁹/L (Grade 3-4) neutropenia during treatment with UKONIQ. Consider supportive care as appropriate. Withhold, reduce dose, or discontinue UKONIQ depending on the severity and persistence of neutropenia.

Diarrhea or Non-Infectious Colitis: Serious diarrhea or non-infectious colitis occurred in patients treated with UKONIQ. Any grade diarrhea or colitis occurred in 53% of 335 patients and Grade 3 occurred in 9%. For patients with severe diarrhea (Grade 3, i.e., > 6 stools per day over baseline) or abdominal pain, stool with mucus or blood, change in bowel habits, or peritoneal signs, withhold UKONIQ until resolved and provide supportive care with antidiarrheals or enteric acting steroids as appropriate. Upon resolution, resume UKONIQ at a reduced dose. For recurrent Grade 3 diarrhea or recurrent colitis of any grade, discontinue UKONIQ. Discontinue UKONIQ for life-threatening diarrhea or colitis.

Hepatotoxicity: Serious hepatotoxicity occurred in patients treated with UKONIQ. Grade 3 and 4 transaminase elevations (ALT and/or AST) occurred in 8% and <1%, respectively, in 335 patients. Monitor hepatic function at baseline and during treatment with UKONIQ. For ALT/AST greater than 5 to less than 20 times ULN, withhold UKONIQ until return to less than 3 times ULN, then resume at a reduced dose. For ALT/AST elevation greater than 20 times ULN, discontinue UKONIQ.

Severe Cutaneous Reactions: Severe cutaneous reactions, including a fatal case of exfoliative dermatitis, occurred in patients treated with UKONIQ. Grade 3 cutaneous reactions occurred in 2% of 335 patients and included exfoliative dermatitis, erythema, and rash (primarily maculo-papular). Monitor patients for new or worsening cutaneous reactions. Review all concomitant medications and discontinue any potentially contributing medications. Withhold UKONIQ for severe (Grade 3) cutaneous reactions until resolution. Monitor at least weekly until resolved. Upon resolution, resume UKONIQ at a reduced dose. Discontinue UKONIQ if severe cutaneous reaction does not improve, worsens, or recurs. Discontinue UKONIQ for life-threatening cutaneous reactions or SJS, TEN, or DRESS of any grade. Provide supportive care as appropriate.

Allergic Reactions Due to Inactive Ingredient FD&C Yellow No. 5: UKONIQ contains FD&C Yellow No. 5 (tartrazine), which may cause allergic-type reactions (including bronchial asthma) in certain susceptible persons, frequently in patients who also have aspirin hypersensitivity.

Embryo-fetal Toxicity: Based on findings in animals and its mechanism of action, UKONIQ can cause fetal harm when administered to a pregnant woman. Advise pregnant women of the potential risk to a fetus. Advise females and males with female partners of reproductive potential to use effective contraception during treatment and for at least one month after the last dose.

Serious adverse reactions occurred in 18% of 221 patients who received UKONIQ. Serious adverse reactions that occurred in ≥2% of patients were diarrhea-colitis (4%), pneumonia (3%), sepsis (2%), and urinary tract infection (2%). Permanent discontinuation of UKONIQ due to an adverse reaction occurred in 14% of patients. Dose reductions of UKONIQ due to an adverse reaction occurred in 11% of patients. Dosage interruptions of UKONIQ due to an adverse reaction occurred in 43% of patients.

The most common adverse reactions (>15%), including laboratory abnormalities, in 221 patients who received UKONIQ were increased creatinine (79%), diarrhea-colitis (58%, 2%), fatigue (41%), nausea (38%), neutropenia (33%), ALT increase (33%), AST increase (32%), musculoskeletal pain (27%), anemia (27%), thrombocytopenia (26%), upper respiratory tract infection (21%), vomiting (21%), abdominal pain (19%), decreased appetite (19%), and rash (18%).

Lactation: Because of the potential for serious adverse reactions from umbralisib in the breastfed child, advise women not to breastfeed during treatment with UKONIQ and for at least one month after the last dose.

Please visit www.tgtherapeutics.com/prescribing-information/uspi-ukon for full Prescribing Information and Medication Guide.

Cautionary Statement
This press release contains forward-looking statements that involve a number of risks and uncertainties. For those statements, we claim the protection of the safe harbor for forward-looking statements contained in the U.S. Private Securities Litigation Reform Act of 1995. Such forward-looking statements include but are not limited to statements regarding the expectations and plans for the clinical trials evaluating TG-1701 as monotherapy and in combination with UKONIQ^® (umbralisib) and ublituximab (U2), the availability of results from those trials, and the potential of TG-1701 as a treatment for CLL.

In addition to the risk factors identified from time to time in our reports filed with the U.S. Securities and Exchange Commission, factors that could cause our actual results to differ materially are the following: the risk that interim, top-line, or other early clinical trial results, including the clinical studies evaluating TG-1701 in combination with U2, will not be reproduced in final data sets or in future studies; the risk that the safety profile observed with TG-1701 as monotherapy and in combination with U2, may change as additional patients are exposed for longer durations; the risk that TG-1701 as monotherapy or in combination with U2 will not prove to be safe and efficacious; the uncertainties inherent in research and development; and the risk that the ongoing COVID-19 pandemic has an adverse impact on our research and development plans or commercialization efforts. Further discussion about these and other risks and uncertainties can be found in our Annual Report on Form 10-K for the fiscal year ended December 31, 2020, as updated by our subsequent Quarterly Reports on Form 10-Q, and in our other filings with the U.S. Securities and Exchange Commission.

Any forward-looking statements set forth in this press release speak only as of the date of this press release. We do not undertake to update any of these forward-looking statements to reflect events or circumstances that occur after the date hereof. This press release and prior releases are available at www.tgtherapeutics.com. The information found on our website is not incorporated by reference into this press release and is included for reference purposes only.

CONTACT:

Investor Relations
Email: ir@tgtxinc.com
Telephone: 1.877.575.TGTX (8489), Option 4

Media Relations:
Email: media@tgtxinc.com
Telephone: 1.877.575.TGTX (8489), Option 6

FAQ

What were the results of TG-1701 in the clinical trial for CLL?

TG-1701 showed a 100% overall response rate (ORR) in CLL patients at 300 mg QD, according to the data presented at the ASCO Annual Meeting.

What is the significance of the combination therapy involving TG-1701?

The triple combination of TG-1701 with ublituximab and UKONIQ (U2) resulted in a 79% overall response rate and a 21% complete response rate, indicating promising efficacy.

What safety concerns were reported with TG-1701 and UKONIQ?

Grade 3 adverse events included diarrhea (11%) and elevated liver enzymes (ALT/AST increases at 16%). Serious adverse reactions were noted in 18% of patients treated with UKONIQ.

When were the TG-1701 trial results presented?

The results of the TG-1701 trial were presented on June 4, 2021, at the American Society of Clinical Oncology (ASCO) Annual Meeting.