Tonix Pharmaceuticals Announces Presentation of Phase 1 Data and Outlines Planned Adaptive Phase 2 Field Study of TNX-4800 for the Prevention of Lyme Disease, at the World Vaccine Congress Washington 2026

Rhea-AI Summary

Tonix Pharmaceuticals (Nasdaq: TNXP) reported Phase 1 results for TNX-4800, a single-dose anti-Borrelia burgdorferi OspA monoclonal antibody showing safety, tolerability, and pharmacokinetics consistent with ~four months protection.

The company plans a randomized, double-blind, placebo-controlled adaptive Phase 2 field study (fixed 350 mg dose) expected to start in H1 2027, pending FDA clearance.

Positive

• Phase 1 safety: no significant clinical or lab safety signals in 44 subjects
• Durable exposure: mean half-life 62–69 days with quantifiable levels >200 days in most subjects
• Selected Phase 2 dose: 350 mg fixed dose expected to match Phase 1 5 mg/kg exposures

Negative

• Small Phase 1: only 44 subjects enrolled, limiting statistical confidence
• Endpoint reliance: four-month primary endpoint based on in vitro MEC and PK bridging, not clinical efficacy yet
• Regulatory dependency: Phase 2 start and potential CHIM study contingent on FDA clearance

Market Reaction – TNXP

+8.06% $13.00

15m delay 10 alerts

+8.06% Since News

$13.00 Last Price

$12.16 $13.17 Day Range

+$13M Valuation Impact

$174.27M Market Cap

0.5x Rel. Volume

Following this news, TNXP has gained 8.06%, reflecting a notable positive market reaction. Our momentum scanner has triggered 10 alerts so far, indicating notable trading interest and price volatility. The stock is currently trading at $13.00. This price movement has added approximately $13M to the company's valuation.

Data tracked by StockTitan Argus (15 min delayed). Upgrade to Silver for real-time data.

Key Figures

Phase 1 enrollment: 44 subjects Phase 1 completions: 41 subjects Dose range: 0.5, 1.5, 5, 10 mg/kg +5 more

8 metrics

Phase 1 enrollment 44 subjects Healthy adults 19–65 years in TNX-4800 Phase 1 trial

Phase 1 completions 41 subjects Subjects completing TNX-4800 Phase 1 study

Dose range 0.5, 1.5, 5, 10 mg/kg Single subcutaneous TNX-4800 doses vs placebo

Mean half-life 62–69 days Mean TNX-4800 half-life across Phase 1 cohorts

Duration at lowest dose >200 days in 80% of subjects TNX-4800 levels quantifiable at lowest dose

Max duration higher doses Up to 350 days TNX-4800 levels quantifiable at ≥1.5 mg/kg

Concentration at 4 months ≈10 μg/ml 5 mg/kg cohort, about 2× minimum effective concentration

Planned Phase 2 dose 350 mg SC single dose Adaptive Phase 2 field study for Lyme prevention

Market Reality Check

Price: $12.03 Vol: Volume 744,241 is 1.64x t...

high vol

$12.03 Last Close

Volume Volume 744,241 is 1.64x the 20-day average, indicating elevated trading interest ahead of/around this update. high

Technical Shares at $12.03 are trading below the 200-day MA of $24.47 and sit close to the 52-week low of $11.60.

Peers on Argus

TNXP fell 6.6% while key biotech peers were mixed: NMRA -10.23%, CADL -6.67%, VN...

1 Up

TNXP fell 6.6% while key biotech peers were mixed: NMRA -10.23%, CADL -6.67%, VNDA -2.64%, ANNX -1.1%, and OMER up 3.06%. Only OMER appeared on the momentum scanner, moving up, so TNXP’s decline looks more stock-specific than a unified sector move.

Previous Clinical trial Reports

5 past events · Latest: Mar 26 (Positive)

Same Type Pattern 5 events

Date	Event	Sentiment	Move	Catalyst
Mar 26	Phase 1 dosing start	Positive	-8.3%	First participant dosed in Phase 1 PD study of TNX-1900 for migraine model.
Mar 10	Post hoc Phase 3 data	Positive	+1.6%	Post hoc Phase 3 TONMYA analyses showing rapid pain relief and strong endpoints.
Jan 30	Phase 3 data presentation	Positive	-5.4%	Positive Phase 3 RESILIENT data for TONMYA presented at pain therapeutics summit.
Dec 29	TNX-4800 program update	Positive	+0.1%	Program updates on long-acting TNX-4800 Lyme prophylaxis and 2027 clinical timing.
Nov 24	IND clearance	Positive	-11.3%	FDA IND clearance for Phase 2 HORIZON study of TNX-102 SL in MDD.

Pattern Detected

Clinical and trial-related updates for Tonix have often been followed by negative price reactions, even when data or milestones were positive.

Recent Company History

Over the past months, Tonix has frequently reported clinical milestones across its pipeline. Positive Phase 3 data and post hoc analyses for TONMYA, IND clearance for TNX-102 SL in major depressive disorder, program updates on TNX-4800 for Lyme disease, and a recent Phase 1 start for TNX-1900 all framed a clinically active story. Yet several of these clinical trial announcements coincided with share price declines, indicating a pattern where new data have not consistently translated into positive near-term market reactions. Today’s TNX-4800 Phase 1 results and Phase 2 plans fit into this clinically busy backdrop.

Historical Comparison

-4.6% avg move · In the past year, Tonix’s clinical trial headlines produced an average move of -4.64%. Today’s -6.6%...

clinical trial

-4.6%

Average Historical Move clinical trial

In the past year, Tonix’s clinical trial headlines produced an average move of -4.64%. Today’s -6.6% reaction to TNX-4800 Phase 1 data is somewhat more negative but directionally consistent with that pattern.

TNX-4800 moved from 2025 program updates and 2027 planning to detailed Phase 1 safety/PK data and a defined adaptive Phase 2 field study design for seasonal Lyme prophylaxis.

Regulatory & Risk Context

Active S-3 Shelf

Shelf Active

Active S-3 Shelf Registration 2025-09-04

Tonix has an amended S-3/A shelf registration dated 2025-09-04, with at least one prior usage via a 424B5 prospectus supplement in November 2025. The amendment described re-filing of an auditor consent exhibit and did not change the base prospectus terms. Specific capacity amounts are not detailed here.

Market Pulse Summary

The stock is up +8.1% following this news. A strong positive reaction would have aligned with Tonix’...

Analysis

The stock is up +8.1% following this news. A strong positive reaction would have aligned with Tonix’s clinically active story but contrasted with its historical pattern of negative moves on trial news, where similar headlines averaged -4.64%. Sustaining substantial gains could be challenged by prior dilution capacity under its S-3/A shelf and the stock’s position well below its $24.47 200-day MA and $69.97 52-week high, factors that may encourage profit-taking.

Key Terms

monoclonal antibody, pharmacokinetics, cmax, half-life, +4 more

8 terms

monoclonal antibody medical

"TNX-4800 is a long-acting borreliacidal (or bactericidal), human monoclonal antibody (mAb)..."

A monoclonal antibody is a laboratory-made protein designed to recognize and attach to a specific target in the body, such as a disease-causing substance or cell. It functions like a highly precise lock-and-key tool, helping to treat or detect illnesses. For investors, companies developing monoclonal antibodies can represent promising opportunities in the healthcare sector, especially as these treatments often address unmet medical needs.

pharmacokinetics medical

"Phase 1 study of TNX-4800 demonstrated safety, tolerability, and pharmacokinetics supportive..."

Pharmacokinetics is the study of how a substance, such as a drug or chemical, moves through and is processed by the body over time. It tracks how it is absorbed, distributed, broken down, and eventually eliminated. For investors, understanding pharmacokinetics helps gauge the effectiveness, safety, and potential risks of new medications or treatments, which can influence a company’s success and valuation in the healthcare industry.

cmax medical

"Peak serum concentration (Cmax) increased by ~25-fold for a 20-times increase in dose."

Cmax is the highest concentration of a drug measured in the bloodstream after a dose, like the peak of a wave after a stone is dropped into water. It matters to investors because that peak helps regulators and doctors judge safety and likely effectiveness, informs dosing schedules, and is used to compare formulations or generics—data that can affect a drug’s approval, marketability, and commercial value.

half-life medical

"The mean half-life ranged from 62-69 days across TNX-4800 cohorts."

Half-life is the time it takes for a quantity (such as a drug in the body, a radioactive substance, or a decaying revenue stream) to decrease to half its original amount. Think of it like the time it takes for a hot cup of coffee to cool to half its initial warmth: it tells you how quickly the effect fades. For investors, half-life helps estimate how long a product’s impact, a payment stream, or a risk factor will meaningfully influence a company’s performance.

randomized, double-blind medical

"a randomized, double-blind, placebo-controlled, adaptive Phase 2 field study..."

A randomized, double-blind study is a clinical trial design where participants are assigned by chance to different groups (for example, a new treatment or a control) and neither the participants nor the researchers know who is in which group. This setup reduces conscious or unconscious bias—think of it like a blind taste test—so results are more reliable and investors can have greater confidence that reported effects reflect the treatment itself rather than expectations or selective reporting.

placebo-controlled medical

"a randomized, double-blind, placebo-controlled, adaptive Phase 2 field study..."

"Placebo-controlled" describes a testing method where one group receives the actual treatment or intervention, while another group receives a harmless, inactive version called a placebo. This approach helps determine whether the real treatment has genuine effects beyond psychological expectations. For investors, understanding this ensures confidence that reported benefits are real and not influenced by bias or false perceptions.

subcutaneous medical

"as a prophylactic that is administered in a single subcutaneous (SC) dose..."

Subcutaneous means situated or applied just beneath the skin. In finance, the term can describe processes or investments that are hidden or not immediately visible, much like something placed under the skin that isn't easily seen from the outside. Recognizing subcutaneous activities helps investors understand underlying factors that may influence markets or asset values over time.

controlled human infection model medical

"the Company plans to initiate a controlled human infection model (CHIM) study in 2028."

A controlled human infection model is a clinical research approach where healthy, consenting volunteers are intentionally exposed to a known infectious agent under close medical supervision to test vaccines or treatments faster and with fewer participants. For investors, these studies can shorten development timelines, lower costs and de-risk early-stage products, but they also carry ethical, safety and regulatory considerations that can affect a program’s timeline, approval chances and company valuation.

AI-generated analysis. Not financial advice.

TNX-4800 is a long-acting anti-Borrelia burgdorferi OspA human monoclonal antibody in development as a single-dose Lyme prophylactic

Phase 1 study of TNX-4800 demonstrated safety, tolerability, and pharmacokinetics supportive of approximately four months protection

Company expects to initiate a randomized, double-blind, placebo-controlled, adaptive Phase 2 field study in the first half of 2027, pending FDA clearance

BERKELEY HEIGHTS, N.J., March 31, 2026 (GLOBE NEWSWIRE) -- Tonix Pharmaceuticals Holding Corp. (Nasdaq: TNXP) (“Tonix” or the “Company”), a fully integrated, commercial biotechnology company, announced Phase 1 data of TNX-4800 (formerly known as mAb 2217LS)^1,2 was presented by Mark S. Klempner, MD, professor of medicine at UMass Chan Medical School, an inventor of TNX-4800 and principal investigator of the study, on March 30, 2026, at the World Vaccine Congress Washington 2026. Tonix also announced its planned strategy for an adaptive Phase 2 field study expected to initiate in the first half of 2027, pending FDA clearance.

TNX-4800 is a long-acting borreliacidal (or bactericidal), human monoclonal antibody (mAb) with an engineered crystallizable fragment (Fc) domain for an extended half-life that targets the outer surface protein A (OspA) of Borrelia burgdorferi, which causes 99.9% of Lyme disease cases in the U.S.^3,4 Tonix is developing TNX-4800, which the Company in-licensed from UMass Chan Medical School in 2025, as a prophylactic that is administered in a single subcutaneous (SC) dose expected to provide approximately four months protection to people in endemic areas during the U.S. tick season. There are currently no marketed U.S. Food and Drug Administration (FDA)-approved vaccines or prophylactics to protect against Lyme disease.

“TNX-4800 is expected to provide a preventative option to the 87 million⁵ people in the United States who are at high risk of contracting the disease because they live, work, or vacation in a tick-endemic area,” said Seth Lederman, MD, Chief Executive Officer of Tonix Pharmaceuticals. “As a monoclonal antibody, we believe TNX-4800 offers significant advantages over vaccines in development. Lyme disease vaccines that elicit antibodies to OspA currently in development take more than six months to offer protection and require complex immunization schedules. A previously approved anti-OspA vaccine was withdrawn due to poor uptake,⁶ potentially relating to its complex immunization schedule.”

Dr. Lederman continued, “TNX-4800, targeting Borrelia burgdorferi, the serotype that causes 99.9% of Lyme disease in the U.S., is a single dose subcutaneous administration that potentially offers immunity within two days for a duration of approximately four months. We believe TNX-4800’s differentiating characteristics could offer meaningful improvements for people seeking protection from Lyme disease. We believe the Phase 1 pharmacokinetic (PK) data support our plan to conduct an adaptive field study in the first half of 2027, pending FDA clearance, in which protection at four months is the primary endpoint, and protection at six months is a key secondary endpoint.”

Phase 1 Results

“Our study demonstrated potentially protective blood levels of TNX-4800 at two days, with protective blood levels sustained for at least four months due to its extended half-life design,” said Dr. Klempner. “Additionally, with its differentiated mechanism of action, TNX-4800 has the potential to provide passive immunity by directly supplying neutralizing antibodies, bypassing the need for a vaccine to induce a patient’s immune system to generate its own antibodies, which can be associated with other issues. We look forward to further clinical investigation of TNX-4800 as we strive to overcome this major public health challenge.”

The primary objective of the Phase 1 study was to evaluate the safety and tolerability of a SC injection of TNX-4800 when administered to healthy male and female subjects ages 19-65 years old. The secondary objective was to evaluate the PK of a SC dose of TNX-4800 when administered to healthy subjects. 44 subjects were enrolled, with 41 subjects completing the study. Subjects received a single SC administration of placebo or TNX-4800 at 0.5, 1.5, 5, or 10 mg/kg.

Results showed no significant clinical or laboratory safety signals, with most adverse events mild or moderate. Peak serum concentration (Cmax) increased by ~25-fold for a 20-times increase in dose. Serum TNX-4800 was measurable at earliest sampling time of two days, indicating rapid systemic absorption. TNX-4800 levels remained quantifiable for >200 days in 80% of subjects at the lowest dose, and for up to 350 days in the majority of subjects at higher doses (i.e., ≥ 1.5 mg/kg). The mean half-life ranged from 62-69 days across TNX-4800 cohorts. Serum concentrations were quantifiable for up to 12 months in most subjects.

• Mean exposure for the 10 mg/kg cohort had <17% of the highest exposures in a nonclinical toxicology study.
• The maximum half-life ranged from 81-104 days, with the 10mg/kg cohort at 97 days and 5mg/kg cohort at 87 days.
• In the 5mg/kg dose cohort, mean serum TNX-4800 concentration was approximately 10 μg/ml at four months, which was approximately twice the minimum effective concentration, or MEC, calculated from in vitro bactericidal activity, and approximately the MEC from in vitro tick-feeding experiments. These data support Tonix’s planned evaluation of protection at four months as the proposed primary endpoint.
  

Adaptive Phase 2 Field Study Plans

Pending FDA clearance, the Company plans to initiate an adaptive field study in the first half of 2027. TNX-4800 will be studied in a randomized, double-blind, placebo-controlled, adaptive Phase 2 field study to evaluate the efficacy of a single SC dose of TNX-4800, 350 mg, in preventing the first occurrence of confirmed Lyme disease during the primary efficacy surveillance period (Day 3 through Month 4 following administration). Based on the Phase 1 PK data, a fixed dose of 350 mg was selected for the Phase 2 field study, which is expected to provide exposures comparable to the 5 mg/kg dose evaluated in Phase 1. Participants will include adolescents and adults 16 to 65 years of age in Lyme-endemic areas in the U.S. The primary endpoint will be the prevention of Lyme disease at four months (comparison of TNX-4800 group and placebo group). A key secondary endpoint will be the prevention of Lyme disease at six months (comparison of TNX-4800 and placebo).

The Company expects to have GMP investigational product available for clinical testing in early 2027. Additionally, if necessary and pending FDA clearance, the Company plans to initiate a controlled human infection model (CHIM) study in 2028.

A copy of Dr. Klempner’s World Vaccine Congress Washington 2026 presentation is available under the Scientific Presentations tab on the Tonix website at https://www.tonixpharma.com/scientific-presentations. The Company’s TNX-4800 specific presentation can be found under the Presentations tab on the Investors section of the Tonix website at https://ir.tonixpharma.com/presentations.

About TNX-4800
TNX-4800 (formerly known as mAb 2217LS) is a long-acting borreliacidal (or bactericidal), human monoclonal antibody with an engineered extended half-life that targets the outer-surface protein A (OspA) on Lyme-causing Borrelia bacteria. When TNX-4800-containing blood is ingested by the tick, TNX-4800 kills and blocks the maturation of Borrelia burgdorferi in the mid-gut of infected deer ticks. The Company in-licensed TNX-4800 from UMass Chan Medical School in 2025. Published work in animals showed that TNX-4800 was 95% effective at preventing infection of non-human primates after six days of exposure to ticks infected with Borrelia burgdorferi.¹ TNX-4800 was derived from mAb 2217 by amino acid substitutions in its Fc domain, which serve to prolong the serum half-life. A single administration is designed to potentially provide immunity against Lyme disease within two days and maintain protective antibody levels for approximately four months, without relying on the recipient’s immune system to generate antibodies. TNX-4800 also avoids the multidose priming schedules required for OspA vaccines in development⁷ and the FDA-approved vaccine that was withdrawn from the market.⁸ 

About the TNX-4800 Phase 1 Study
TNX-4800 was studied in a randomized, double-blind, sequential dose-escalation study (NCT04863287) that evaluated safety, tolerability, PK, and immunogenicity of TNX-4800 in healthy adults. 44 subjects were randomized, and 41 completed the study. Subjects received a single SC administration of placebo or TNX-4800 at 0.5, 1.5, 5, or 10 mg/kg. Safety was assessed via clinical and lab evaluations. Drug exposure increased by approximately 25 times for a 20-times increase in dose. Serum TNX-4800 was measurable at the earliest sampling time of two days, indicating rapid systemic absorption. TNX-4800 concentrations remained quantifiable for >200 days in 80% of volunteers at the lowest dose and for up to 350 days in the majority of volunteers at higher doses (i.e., ≥ 1.5 mg/kg). Mean half-life ranged from 62-69 days across groups. Serum concentrations remained quantifiable for up to 12 months in most subjects. Mean exposure for the 10 mg/kg cohort was less than 17% of the highest exposures in a rat toxicology study. Anti-drug antibodies were detected in <10% of treated subjects, with no impact on PK. Most adverse events were mild or moderate. TNX-4800 was determined to be generally safe and well tolerated.

About Lyme Disease 
In the United States, Lyme disease is caused by the bacterium Borrelia burgdorferi. Lyme disease remains the most common vector-borne infection in the United States, and its incidence is climbing each year, due in part to global changes in climate expanding the habitat range for ticks.⁹ 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, heart, and 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. 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.¹⁰

Citations
¹Schiller ZA, et al. J Clin Invest. 2021 131(11):e144843.
²Wang Y, et al. J Infect Dis. 2016. 214(2):205-11.
³Marques AR, et al. Emerg Infect Dis. 2021. 27(8):2017-2024.
⁴Pritt BS, et al. Lancet Infect Dis. 2016. 6(5):556-564.
⁵Kugeler KJ, et al. Emerg Infect Dis. 2021. 27(2):616-619.
⁶ Nigrovic LE, et al. Epidemiol Infect. 2006. Aug 8;135(1):1-8.
⁷Comstedt P, et al. Vaccine. 2015 33(44):5982-8.
⁸Connaught’s (ImuLyme™) and SmithKline Beecham’s (LYMErix™) Lyme disease vaccines were withdrawn. Nigrovic LE, et al. Epidemiol Infect. 2007 135(1):1-8.
⁹Gomes-Solecki M, et. al. Clin Infect Dis. 2020 70(8):1768-1773.
¹⁰National Academies of Sciences, Engineering, and Medicine. 2025. Charting a Path Toward New Treatments for Lyme Infection-Associated Chronic Illnesses. Washington, DC: The National Academies Press. https://doi.org/10.17226/28578.

Tonix Pharmaceuticals Holding Corp.
Tonix Pharmaceuticals* is a fully-integrated, commercial-stage biotechnology company focused on central nervous system (CNS) and immunology treatments in areas of high unmet medical need. TONMYA^® (cyclobenzaprine HCl sublingual tablets 2.8 mg), is the first new treatment for fibromyalgia in adults in more than 15 years. Tonix’s CNS commercial infrastructure supports its marketed products, including its acute migraine products, Zembrace^® SymTouch^® (sumatriptan injection 3 mg) and Tosymra^® (sumatriptan nasal spray 10 mg). Tonix is investigating TONMYA^® in Phase 2 clinical trials to evaluate its potential in major depressive disorder and acute stress disorder/acute stress reaction. In addition, the Company’s CNS portfolio includes TNX-2900 (intranasal oxytocin), which is Phase 2 ready for the treatment of Prader-Willi syndrome, a rare disease. Tonix is also advancing a pipeline of immunology programs, including TNX-4800, a Phase 2 ready long-acting human anti-Borrelia OspA monoclonal antibody (mAb) for the prevention of Lyme disease in the U.S., and TNX-1500, a Phase 2 ready third-generation CD40 ligand inhibitor for the prevention of kidney transplant rejection. To learn more, visit www.tonixpharma.com and follow the Company on LinkedIn and X.

*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.

Zembrace SymTouch and Tosymra are registered trademarks of Tonix Medicines. TONMYA is a registered trademark of Tonix Pharma Limited. All other marks are property of their respective owners.

About 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.

Forward Looking Statements
Certain statements in this press release are forward-looking within the meaning of the Private Securities Litigation Reform Act of 1995 including those relating to the completion of the offering, the satisfaction of customary closing conditions, the intended use of proceeds from the offering and other statements that are predictive in nature. These statements may be identified by the use of forward-looking words such as “anticipate,” “believe,” “forecast,” “estimate,” “expect,” and “intend,” among others. There are a number of factors that could cause actual events to differ materially from those indicated by such forward-looking statements. These factors include, but are not limited to, risks related to the failure to successfully launch and commercialize TONMYA^® and any of our approved products; risks related to the failure to obtain FDA clearances or approvals and noncompliance with FDA regulations; risks related to the timing and progress of clinical development of our product candidates; our need for additional financing; uncertainties of patent protection and litigation; uncertainties of government or third party payor reimbursement; limited research and development efforts and dependence upon third parties; and substantial competition. As with any pharmaceutical under development, there are significant risks in the development, regulatory approval and commercialization of new products. Tonix does not undertake an obligation to update or revise any forward-looking statement. Investors should read the risk factors set in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025, as filed with the SEC on March 12, 2026, and periodic reports filed with the SEC on or after the date thereof. Tonix does not undertake an obligation to update or revise any forward-looking statement. All of Tonix’s forward-looking statements are expressly qualified by all such risk factors and other cautionary statements. The information set forth herein speaks only as of the date thereof.

Investor Contacts
Jessica Morris
Tonix Pharmaceuticals
investor.relations@tonixpharma.com
(862) 799-8599

Brian Korb
astr partners
(917) 653-5122
brian.korb@astrpartners.com

Media Contacts
Deborah Elson
Tonix Pharmaceuticals
deborah.elson@tonixpharmaceuticals.com

Ray Jordan
Putnam Insights
ray@putnaminsights.com

FAQ

What did Tonix (TNXP) report from the Phase 1 study of TNX-4800 on March 30, 2026?

Phase 1 showed safety, tolerability, and PK supporting about four months protection. According to the company, 44 subjects enrolled, most adverse events were mild or moderate, and serum levels were measurable two days after dosing.

When does Tonix plan to start the adaptive Phase 2 field study for TNX-4800 (TNXP)?

Tonix expects to initiate the adaptive Phase 2 field study in the first half of 2027, pending FDA clearance. According to the company, investigational product availability is planned for early 2027 to support that timeline.

What dose of TNX-4800 will Tonix (TNXP) study in the Phase 2 field trial and why?

A fixed 350 mg single subcutaneous dose was selected for Phase 2 to match exposures of the 5 mg/kg Phase 1 cohort. According to the company, PK data supported comparable exposure and predicted four-month protection.

How long did TNX-4800 remain detectable in Phase 1 participants reported by Tonix (TNXP)?

Serum TNX-4800 was measurable at two days and remained quantifiable >200 days in most subjects. According to the company, some subjects had quantifiable levels up to 350 days and up to 12 months in many subjects.

What is the primary endpoint for Tonix's (TNXP) planned Phase 2 TNX-4800 field study?

The primary endpoint is prevention of confirmed Lyme disease from Day 3 through Month 4 after dosing. According to the company, prevention at four months is primary and prevention at six months is a key secondary endpoint.

Are there safety concerns from the TNX-4800 Phase 1 data for Tonix (TNXP)?

No significant clinical or laboratory safety signals were reported in the Phase 1 study. According to the company, most adverse events were mild or moderate and mean exposure at 10 mg/kg was within nonclinical toxicology limits.