Full Press Release Details
TONIX PHARMACEUTICALS HOLDING CORP. 8-K
Tonix Pharmaceuticals Announces In-licensing Phase
Monoclonal Antibody Designed for Seasonal Prevention of Lyme Disease (TNX-4800)
Positive Phase 1 study showed
safety, tolerability and a linear pharmacokinetic: pharmacodynamic: efficacy relationship (1: 1: 1)
Planning adaptive Phase 2/3
Approximately 70 million people
that are eligible for treatment live in areas of the U.S. in which Lyme Disease is endemic
CHATHAM, N.J., September 17, 2025 (GLOBE
NEWSWIRE) - Tonix Pharmaceuticals Holding Corp. (Nasdaq: TNXP) ("Tonix" or the "Company"), a fully-integrated
biopharmaceutical company with marketed products and a pipeline of development candidates, today announced the in-licensing of worldwide
rights to TNX-4800 (formerly known as mAb 2217LS)1, which is a long-acting human monoclonal antibody that targets the outer
surface protein A (OspA) of Borrelia burgdorferi, the causative agent of Lyme disease in humans. TNX-4800 is being developed for
annual seasonal use, as one subcutaneous dose administered in the Spring to protect against Lyme disease through Fall, or the entire
tick season in the U.S. TNX-4800 was developed by researchers at UMass Chan Medical School, which is licensing the technology to Tonix.
There are currently no FDA-approved vaccines or prophylactics to protect against Lyme Disease.
"Lyme disease remains the most common vector-borne
infection in the United States and its incidence is climbing each year,"2 said Seth Lederman, M.D., Chief Executive Officer
of Tonix Pharmaceuticals. "Licensing TNX-4800 expands our infectious disease pipeline with a potentially differentiated, single-dose
approach that can be given each Spring to provide protection within two days and protect through Fall, which is the entire tick season
in the U.S. We believe TNX-4800's long-acting monoclonal antibody prophylaxis could play an important role for preventing Lyme for
millions of people who live, work, and vacation in regions endemic for Lyme disease. TNX-4800's novel mechanism of blocking the
maturation of Borrelia in the midgut of infected ticks is consistent with Tonix's focus on innovation. We look forward to
advancing the TNX-4800 program."
"Preventing Lyme disease is an urgent public
health priority, and more than thirty years of clinical experience confirm that monoclonal antibodies can be delivered safely and can
be effective in preventing infections," said Mark Klempner, M.D., Professor of Medicine at UMass Chan Medical School and leader
of the research team that discovered and developed mAb 2217LS. "We are delighted to be collaborating with Tonix on the development
of this program. TNX-4800 is a single dose and provides immediate immunity to the bacteria that causes Lyme disease, which is very different
from Lyme disease vaccine programs currently in development."
Terence R. Flotte, MD, Provost, Dean and Executive
Deputy Vice Chancellor of UMass Chan Medical School, said, "We are proud to partner with Tonix Pharmaceuticals to advance the development
of our novel monoclonal antibody as a prophylactic for Lyme disease, which is an urgent and growing public health challenge in the United
States and around the world. This collaboration reflects UMass Chan's enduring commitment to translational research that addresses
unmet medical needs, and we are excited to work with Tonix to bring forward science-driven solutions that have the potential to prevent
infection and protect vulnerable populations."
TNX-4800 is a fully human monoclonal antibody with
an engineered extended half-life that targets the outer-surface protein A (OspA) on Lyme-causing Borrelia bacteria. By binding
OspA, TNX-4800 blocks the maturation of Borrelia burgdorferi in the mid-gut of infected deer ticks. The mAb 2217LS1
was derived from mAb 2217 by amino acid substitutions that crystallizable fragment (Fc) domain to prolong the serum half-life. A single
administration in the Spring is designed to maintain protective antibody titers for the entire tick season, providing pre-exposure prophylaxis
against Lyme disease without relying on the recipient's immune system to generate antibodies. By delivering a well-characterized
antibody directly, TNX-4800 has been shown to block transmission of the major Borrelia genospecies from ticks to animals. TNX-4800
sidesteps the multidose schedules required for OspA vaccines in development3 and FDA-approved vaccines that have been withdrawn
from the market due to concerns about increased risk of autoimmunity. 4 Tonix intends to advance TNX-4800 through additional
clinical trials with the goal of submitting a Biologics Licensing Application (BLA).
In the United States, Lyme disease is caused by the
bacterium Borrelia burgdorferi. It occurs most commonly in the Northeast, mid-Atlantic, and upper-Midwest regions. Lyme disease
bacteria are transmitted through the bite of infected Ixodes ticks. Typical symptoms include fever, headache, fatigue,
and a characteristic skin rash called erythema migrans. If left untreated, infection can spread to joints, the heart, and the nervous
system. Laboratory testing is helpful if used correctly and performed with FDA-cleared tests. Although many cases of Lyme disease can
be treated successfully with antibiotics, diagnosis and treatment are often delayed or missed, and even with treatment, up to 20%
of cases may progress to a Post-Treatment Lyme Disease Syndrome (PTLDS) called "Chronic Lyme" or "Long Lyme".
Chronic Lyme is considered an Infection Associated Chronic Illness (IACI), and is a chronic, debilitating disease state characterized
by joint and muscle pain, fatigue and other symptoms.5
About Borrelia Burgdorferi
In infected deer ticks, Borrelia's OspA
binds to tick-gut receptor TROSPA and helps it adhere to the midgut lining. During a tick bite Borrelia downregulates OspA, upregulates
OspC, and activates motility genes. Borrelia undergoes a metamorphic-like transformation becoming highly flagellated and mobile,
which facilitates migration to the salivary glands and invasion of human host tissues. The mAb 2217LS blocks the metamorphic-like transformation
of Borrelia in the tick's midgut preventing transmission of the bacteria. Lyme-causing Borrelia exposed or infected
individuals, rarely make antibodies against OspA which allows for people to be reinfected despite having immunity to OspC. Consequently
we expect that protection against Borrelia would require annual prophylaxis.
About Monoclonal Antibody Prophylaxis
Two long-acting monoclonal antibody products6,7
have won FDA approval for prophylaxis against respiratory syncytial virus (RSV). AstraZeneca (in partnership with Sanofi) markets Beyfortus
(nirsevimab) and Merck markets Enflonsia (clesrovimab).
Tonix Pharmaceuticals Holding Corp.*
Tonix Pharmaceuticals is a fully-integrated biotechnology
company with marketed products and a pipeline of development candidates. Tonix recently received FDA approval for TonmyaTM,
a first-in-class, non-opioid analgesic medicine for the treatment of fibromyalgia, a chronic pain condition that affects millions of adults.
This marks the first approval for a new prescription medicine for fibromyalgia in more than 15 years. Tonix also markets two treatments
for acute migraine in adults. Tonix's development portfolio is focused on central nervous system (CNS) disorders, immunology, immuno-oncology
and infectious diseases. TNX-102 SL is being developed to treat acute stress reaction and acute stress disorder under a Physician-Initiated
IND at the University of North Carolina in the OASIS study funded by the U.S. Department of Defense (DoD). Tonix's immunology development
portfolio consists of biologics to address organ transplant rejection, autoimmunity and cancer, including TNX-1500, which is an Fc-modified
humanized monoclonal antibody targeting CD40-ligand (CD40L or CD154) being developed for the prevention of allograft rejection and for
the treatment of autoimmune diseases. Tonix's infectious disease portfolio includes TNX-801, a vaccine in development for mpox and
smallpox, as well as TNX-4200 for which Tonix has a contract with the U.S. DoD's Defense Threat Reduction Agency (DTRA) for up to
$34 million over five years. TNX-4200 is a small molecule broad-spectrum antiviral agent targeting CD45 for the prevention or treatment
of infections to improve the medical readiness of military personnel in biological threat environments. Tonix owns and operates a state-of-the
art infectious disease research facility in Frederick, Md.
* Tonix's product development candidates are investigational
new drugs or biologics; their efficacy and safety have not been established and have not been approved for any indication.
This press release and further information about Tonix can be found
UMass Chan Medical School
UMass Chan Medical School, one of five campuses
of the University of Massachusetts system, comprises the T.H. Chan School of Medicine, the Morningside Graduate School of Biomedical
Sciences, the Tan Chingfen Graduate School of Nursing, ForHealth Consulting at UMass Chan Medical School, MassBiologics, and a thriving
Nobel-Prize-winning biomedical research enterprise. UMass Chan is advancing together to improve the
health and wellness of our diverse communities throughout Massachusetts and across the world by leading and innovating in education,
research, health care delivery and public service. It is ranked among the best medical schools in the nation for primary care education
and biomedical research by U.S. News & World Report. Learn more at www.umassmed.edu.
1 Schiller ZA, et al. J Clin Invest. 2021 131(11):e144843.
doi: 10.1172/JCI144843. PMID: 33914704; PMCID: PMC8159683.
2 Gomes-Solecki M, et. al.. Clin Infect Dis. 2020 70(8):1768-1773.
doi: 10.1093/cid/ciz872. PMID: 31620776; PMCID: PMC7155782.
3 Connaught's (ImuLyme ) and SmithKline Beecham's
(LYMErix ) Lyme disease vaccines were withdrawn over concerns about an increased risk of autoimmune arthritis triggered by molecular