TG Therapeutics Announces Data Presentations for BRIUMVI in Multiple Sclerosis at the American Academy of Neurology 2025 Annual Meeting

Rhea-AI Summary

TG Therapeutics (NASDAQ: TGTX) presented three significant data sets for BRIUMVI® (ublituximab-xiiy) in treating relapsing forms of multiple sclerosis (RMS) at the American Academy of Neurology 2025 annual meeting.

Key findings include:

• The ENAMOR survey, covering ~400 patients across 21 MS centers, showed improved tolerability and lower infusion-related reactions compared to Phase 3 trials
• 90% of surveyed patients received acetaminophen pre-medication, potentially explaining the better tolerance rates
• The company announced ENABLE, a new Phase 4 96-week observational study, which will track approximately 500 patients across 100 US MS centers
• Five-year BRIUMVI treatment data showed consistent serious infection rates with Phase 3 trials and no Progressive Multifocal Leukoencephalopathy (PML) cases

Positive

• Real-world data shows improved tolerability profile compared to Phase 3 trials
• No PML cases observed in 5-year treatment data
• Consistent safety profile maintained over long-term use
• Expanding real-world evidence with new 500-patient observational study

Negative

• None.

Insights

Neurologist

The real-world tolerability data from the ENAMOR survey represents a meaningful clinical advancement for BRIUMVI in the MS treatment landscape. The lower rate of infusion-related reactions observed outside clinical trial settings has significant practical implications, as these reactions often present barriers to therapy adoption and adherence.

The observation that acetaminophen premedication (used in 90% of surveyed patients) potentially contributed to improved tolerability offers a simple clinical solution that wasn't captured in the more controlled ULTIMATE trials. This finding provides clinicians with actionable information to optimize the patient experience.

Perhaps most significant is the five-year safety data showing consistent serious infection rates with no observed cases of PML. Progressive multifocal leukoencephalopathy risk remains one of the most concerning safety issues with some MS therapies, particularly other B-cell depleting treatments. This longer-term safety evidence helps address an important clinical uncertainty.

The planned ENABLE Phase 4 study across 100 MS centers will provide additional validation of these findings while generating more comprehensive real-world effectiveness data. Collectively, these updates enhance our understanding of BRIUMVI's clinical profile, supporting more confident treatment decision-making for appropriate relapsing MS patients.

Pharmaceutical Market Analyst

These presentations strategically address key adoption barriers for BRIUMVI in the competitive MS market. The improved infusion tolerability profile demonstrated in the ENAMOR survey directly counters a potential commercial disadvantage compared to oral therapies and other infused options.

The acetaminophen premedication insight provides a simple protocol adjustment that could significantly enhance the patient experience - an important differentiation point when multiple anti-CD20 options exist. TG Therapeutics is effectively using real-world evidence to refine BRIUMVI's positioning post-approval.

The five-year safety data showing no PML cases is particularly valuable for comparative messaging against ocrelizumab and other MS therapies where this rare but serious adverse event has been reported. This safety record strengthens BRIUMVI's risk-benefit profile in long-term treatment discussions.

The planned ENABLE study across approximately 500 patients demonstrates continued investment in building the evidence base needed to drive broader adoption. By generating robust real-world data, TG Therapeutics is following the playbook successful MS therapies have used to gain market share over time.

These clinical updates collectively strengthen BRIUMVI's competitive profile, addressing key prescriber concerns around safety and tolerability that influence treatment selection decisions in this crowded therapeutic category.

NEW YORK, April 08, 2025 (GLOBE NEWSWIRE) -- TG Therapeutics, Inc. (NASDAQ: TGTX), today announced the presentation of data highlighting BRIUMVI® (ublituximab-xiiy) in patients with relapsing forms of multiple sclerosis (RMS), at the American Academy of Neurology 2025 annual meeting. Links to each presentation are included below.

Michael S. Weiss, Chief Executive Officer and Chairman of TG Therapeutics stated, "We were pleased to share three presentations yesterday which we believe demonstrate our continued commitment to improving the patient experience and understanding the long term and real-world profile of BRIUMVI.” Mr. Weiss continued, “The results of the retrospective ENAMOR survey, which includes data from approximately 400 individuals across 21 MS centers who have been treated with BRIUMVI in the real-world setting, showed a favorable tolerability profile, including a lower rate of infusion related reactions at the first BRIUMVI dose than was observed in the ULTIMATE Phase 3 trials. Interestingly, approximately 90% of surveyed patients were given acetaminophen as a pre-medication in this real-world setting, whereas it was excluded as a premed as per protocol in the ULTIMATE Phase 3 trials potentially offering a rationale for the lower rate of infusion related reactions observed. We plan to further evaluate the efficacy and tolerability of BRIUMVI in the real world setting through the ENABLE Phase 4 96-week observational study which will enroll approximately 500 patients across approximately 100 MS centers in the United States. Lastly, we were encouraged to see in the presentation by Dr. Steinman, that after five years of BRIUMVI treatment, the frequency of serious infections remained consistent with the ULTIMATE Phase 3 trials and there were no observed cases of PML.”

TG PRESENTATIONS:

Poster Title: Retrospective Evaluation of Infusion Tolerability: Ublituximab Real-World Observational Survey (ENAMOR)

• Lead Author: Dr. Ed Fox – TG Therapeutics - National Physician Liaison – VP, MS Global Operations
  

Poster Title: ENABLE: The First Phase 4 Observational Study for Patients with Relapsing MS Treated with Ublituximab in Real World Clinical Setting

• Lead Author: Dr. Ed Fox – TG Therapeutics - National Physician Liaison – VP, MS Global Operations
  

Poster Title: No Association Between Decreases in Serum Immunoglobulin (Ig) Levels Below Lower Limit of Normal (LLN) and Serious Infections (SI) with Long-term Ublituximab (UBL) Treatment in Patients with Relapsing Multiple Sclerosis (RMS)

• Lead Author: Lawrence Steinman, MD, Standford University, Standford, CA
  

The above presentations are also available on the Publications page, located within the Pipeline section, of the Company’s website at www.tgtherapeutics.com/publications.cfm.

ABOUT THE ULTIMATE I & II PHASE 3 TRIALS
ULTIMATE I & II are two randomized, double-blind, double-dummy, parallel group, active comparator-controlled clinical trials of identical design, in patients with RMS treated for 96 weeks. Patients were randomized to receive either BRIUMVI, given as an IV infusion of 150 mg administered in four hours, 450 mg two weeks after the first infusion administered in one hour, and 450 mg every 24 weeks administered in one hour, with oral placebo administered daily; or teriflunomide, the active comparator, given orally as a 14 mg daily dose with IV placebo administered on the same schedule as BRIUMVI. Both studies enrolled patients who had experienced at least one relapse in the previous year, two relapses in the previous two years, or had the presence of a T1 gadolinium (Gd)-enhancing lesion in the previous year. Patients were also required to have an Expanded Disability Status Scale (EDSS) score from 0 to 5.5 at baseline. The ULTIMATE I & II trials enrolled a total of 1,094 patients with RMS across 10 countries. These trials were led by Lawrence Steinman, MD, Zimmermann Professor of Neurology & Neurological Sciences, and Pediatrics at Stanford University. Additional information on these clinical trials can be found at www.clinicaltrials.gov (NCT03277261; NCT03277248).

ABOUT BRIUMVI® (ublituximab-xiiy) 150 mg/6 mL Injection for IV
BRIUMVI is a novel monoclonal antibody that targets a unique epitope on CD20-expressing B-cells. Targeting CD20 using monoclonal antibodies has proven to be an important therapeutic approach for the management of autoimmune disorders, such as RMS. BRIUMVI is uniquely designed to lack certain sugar molecules normally expressed on the antibody. Removal of these sugar molecules, a process called glycoengineering, allows for efficient B-cell depletion at low doses.

BRIUMVI is indicated for the treatment of adults with relapsing forms of multiple sclerosis (RMS), to include clinically isolated syndrome, relapsing- remitting disease, and active secondary progressive disease.

A list of authorized specialty distributors can be found at www.briumvi.com.

IMPORTANT SAFETY INFORMATION
Contraindications: BRIUMVI is contraindicated in patients with:

• Active Hepatitis B Virus infection
• A history of life-threatening infusion reaction to BRIUMVI

WARNINGS AND PRECAUTIONS

Infusion Reactions: BRIUMVI can cause infusion reactions, which can include pyrexia, chills, headache, influenza-like illness, tachycardia, nausea, throat irritation, erythema, and an anaphylactic reaction. In MS clinical trials, the incidence of infusion reactions in BRIUMVI-treated patients who received infusion reaction-limiting premedication prior to each infusion was 48%, with the highest incidence within 24 hours of the first infusion. 0.6% of BRIUMVI-treated patients experienced infusion reactions that were serious, some requiring hospitalization.

Observe treated patients for infusion reactions during the infusion and for at least one hour after the completion of the first two infusions unless infusion reaction and/or hypersensitivity has been observed in association with the current or any prior infusion. Inform patients that infusion reactions can occur up to 24 hours after the infusion. Administer the recommended pre-medication to reduce the frequency and severity of infusion reactions. If life-threatening, stop the infusion immediately, permanently discontinue BRIUMVI, and administer appropriate supportive treatment. Less severe infusion reactions may involve temporarily stopping the infusion, reducing the infusion rate, and/or administering symptomatic treatment.

Infections: Serious, life-threatening or fatal, bacterial and viral infections have been reported in BRIUMVI-treated patients. In MS clinical trials, the overall rate of infections in BRIUMVI-treated patients was 56% compared to 54% in teriflunomide-treated patients. The rate of serious infections was 5% compared to 3% respectively. There were 3 infection-related deaths in BRIUMVI-treated patients. The most common infections in BRIUMVI- treated patients included upper respiratory tract infection (45%) and urinary tract infection (10%). Delay BRIUMVI administration in patients with an active infection until the infection is resolved.

Consider the potential for increased immunosuppressive effects when initiating BRIUMVI after immunosuppressive therapy or initiating an immunosuppressive therapy after BRIUMVI.

Hepatitis B Virus (HBV) Reactivation: HBV reactivation occurred in an MS patient treated with BRIUMVI in clinical trials. Fulminant hepatitis, hepatic failure, and death caused by HBV reactivation have occurred in patients treated with anti-CD20 antibodies. Perform HBV screening in all patients before initiation of treatment with BRIUMVI. Do not start treatment with BRIUMVI in patients with active HBV confirmed by positive results for HB surface antigen (HBsAg) and anti-HB tests. For patients who are negative for HBsAg and positive for HB core antibody [HBcAb+] or are carriers of HBV [HBsAg+], consult a liver disease expert before starting and during treatment.

Progressive Multifocal Leukoencephalopathy (PML): Although no cases of PML have occurred in BRIUMVI-treated MS patients, JCV infection resulting in PML has been observed in patients treated with other anti-CD20 antibodies and other MS therapies.

If PML is suspected, withhold BRIUMVI and perform an appropriate diagnostic evaluation. Typical symptoms associated with PML are diverse, progress over days to weeks, and include progressive weakness on one side of the body or clumsiness of limbs, disturbance of vision, and changes in thinking, memory, and orientation leading to confusion and personality changes.

MRI findings may be apparent before clinical signs or symptoms; monitoring for signs consistent with PML may be useful. Further investigate suspicious findings to allow for an early diagnosis of PML, if present. Following discontinuation of another MS medication associated with PML, lower PML-related mortality and morbidity have been reported in patients who were initially asymptomatic at diagnosis compared to patients who had characteristic clinical signs and symptoms at diagnosis.

If PML is confirmed, treatment with BRIUMVI should be discontinued.

Vaccinations: Administer all immunizations according to immunization guidelines: for live or live-attenuated vaccines at least 4 weeks and, whenever possible at least 2 weeks prior to initiation of BRIUMVI for non-live vaccines. BRIUMVI may interfere with the effectiveness of non-live vaccines. The safety of immunization with live or live-attenuated vaccines during or following administration of BRIUMVI has not been studied. Vaccination with live virus vaccines is not recommended during treatment and until B-cell repletion.

Vaccination of Infants Born to Mothers Treated with BRIUMVI During Pregnancy: In infants of mothers exposed to BRIUMVI during pregnancy, assess B-cell counts prior to administration of live or live-attenuated vaccines as measured by CD19+ B-cells. Depletion of B-cells in these infants may increase the risks from live or live-attenuated vaccines. Inactivated or non-live vaccines may be administered prior to B-cell recovery. Assessment of vaccine immune responses, including consultation with a qualified specialist, should be considered to determine whether a protective immune response was mounted.

Fetal Risk: Based on data from animal studies, BRIUMVI may cause fetal harm when administered to a pregnant woman. Transient peripheral B-cell depletion and lymphocytopenia have been reported in infants born to mothers exposed to other anti-CD20 B-cell depleting antibodies during pregnancy. A pregnancy test is recommended in females of reproductive potential prior to each infusion. Advise females of reproductive potential to use effective contraception during BRIUMVI treatment and for 6 months after the last dose.

Reduction in Immunoglobulins: As expected with any B-cell depleting therapy, decreased immunoglobulin levels were observed. Decrease in immunoglobulin M (IgM) was reported in 0.6% of BRIUMVI-treated patients compared to none of the patients treated with teriflunomide in RMS clinical trials. Monitor the levels of quantitative serum immunoglobulins during treatment, especially in patients with opportunistic or recurrent infections, and after discontinuation of therapy until B-cell repletion. Consider discontinuing BRIUMVI therapy if a patient with low immunoglobulins develops a serious opportunistic infection or recurrent infections, or if prolonged hypogammaglobulinemia requires treatment with intravenous immunoglobulins.

Most Common Adverse Reactions: The most common adverse reactions in RMS trials (incidence of at least 10%) were infusion reactions and upper respiratory tract infections.

Physicians, pharmacists, or other healthcare professionals with questions about BRIUMVI should visit www.briumvi.com.

ABOUT BRIUMVI PATIENT SUPPORT
BRIUMVI Patient Support is a flexible program designed by TG Therapeutics to support U.S. patients through their treatment journey in a way that works best for them. More information about the BRIUMVI Patient Support program can be accessed at www.briumvipatientsupport.com.

ABOUT MULTIPLE SCLEROSIS
Relapsing multiple sclerosis (RMS) is a chronic demyelinating disease of the central nervous system (CNS) and includes people with relapsing- remitting multiple sclerosis (RRMS) and people with secondary progressive multiple sclerosis (SPMS) who continue to experience relapses. RRMS is the most common form of multiple sclerosis (MS) and is characterized by episodes of new or worsening signs or symptoms (relapses) followed by periods of recovery. It is estimated that nearly 1 million people are living with MS in the United States and approximately 85% are initially diagnosed with RRMS.1,2 The majority of people who are diagnosed with RRMS will eventually transition to SPMS, in which they experience steadily worsening disability over time. Worldwide, more than 2.3 million people have a diagnosis of MS.¹

ABOUT TG THERAPEUTICS
TG Therapeutics is a fully integrated, commercial stage, biopharmaceutical company focused on the acquisition, development and commercialization of novel treatments for B-cell diseases. In addition to a research pipeline including several investigational medicines, TG has received U.S. Food and Drug Administration (FDA) approval for BRIUMVI® (ublituximab-xiiy), for the treatment of adult patients with relapsing forms of multiple sclerosis (RMS), to include clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease, as well as approval by the European Commission (EC) and the Medicines and Healthcare Products Regulatory Agency (MHRA) for BRIUMVI to treat adult patients with RMS who have active disease defined by clinical or imaging features in Europe and the United Kingdom, respectively. For more information, visit www.tgtherapeutics.com, and follow us on X (formerly Twitter) @TGTherapeutics and on LinkedIn. BRIUMVI® is a registered trademark of TG Therapeutics, Inc.

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 Private Securities Litigation Reform Act of 1995.

Any forward-looking statements in this press release are based on management's current expectations and beliefs and are subject to a number of risks, uncertainties and important factors that may cause actual events or results to differ materially from those expressed or implied by any forward-looking statements contained in this press release. In addition to the risk factors identified from time to time in our reports filed with the U.S. Securities and Exchange Commission (SEC), factors that could cause our actual results to differ materially include the below.

Such forward looking statements include but are not limited to statements regarding the results of the ULTIMATE I & II Phase 3 studies, the ENHANCE Phase 3b study, and BRIUMVI as a treatment for relapsing forms of multiple sclerosis (RMS). Additional factors that could cause our actual results to differ materially include the following: the risk that the data from the ULTIMATE I & II or ENHANCE trials that we announce or publish may change, or the product profile of BRIUMVI may be impacted, as more data or additional endpoints are analyzed; the risk that data may emerge from future clinical studies or from adverse event reporting that may affect the safety and tolerability profile and commercial potential of BRIUMVI; the risk that any individual patient’s clinical experience in the post-marketing setting, or the aggregate patient experience in the post-marketing setting, may differ from that demonstrated in controlled clinical trials such as ULTIMATE I and II; the risk that BRIUMVI will not be commercially successful; our ability to expand our commercial infrastructure, and successfully market and sell BRIUMVI in RMS; the Company’s reliance on third parties for manufacturing, distribution and supply, and a range of other support functions for our commercial and clinical products, including BRIUMVI, and the ability of the Company and its manufacturers and suppliers to produce and deliver BRIUMVI to meet the market demand for BRIUMVI; the failure to obtain and maintain requisite regulatory approvals, including the risk that the Company fails to satisfy post-approval regulatory requirements; the uncertainties inherent in research and development; and general political, economic and business conditions, including the risk that the ongoing COVID-19 pandemic could have on the safety profile of BRIUMVI and any of our other drug candidates as well as any government control measures associated with COVID-19 that could have 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, 2024 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

1. MS Prevalence. National Multiple Sclerosis Society website: https://www.nationalmssociety.org/About-the-Society/MS-Prevalence. Accessed October 26, 2020. 2. Multiple Sclerosis International Federation, 2013 via Datamonitor p.236.

FAQ

What were the key findings from the ENAMOR survey for BRIUMVI (TGTX) in 2025?

The ENAMOR survey of 400 patients across 21 MS centers showed better tolerability and lower infusion-related reactions compared to Phase 3 trials, with 90% of patients receiving acetaminophen pre-medication.

How many patients will be enrolled in TGTX's ENABLE Phase 4 study for BRIUMVI?

The ENABLE Phase 4 observational study will enroll approximately 500 patients across 100 MS centers in the United States over 96 weeks.

What are the long-term safety results for BRIUMVI after 5 years of treatment?

After five years of treatment, BRIUMVI showed consistent serious infection rates with Phase 3 trials and no cases of PML were observed.

How does acetaminophen pre-medication affect BRIUMVI treatment outcomes?

90% of patients receiving acetaminophen pre-medication showed lower infusion-related reactions compared to Phase 3 trials where it was excluded, suggesting improved tolerability.