VALION BIO BRIEFS SENIOR DEPARTMENT OF WAR AND BARDA OFFICIALS IN JOINT ENGAGEMENT ON ENTOLIMOD FOR ACUTE RADIATION SYNDROME

Cross-Agency Discussion Highlights Interest in Oral Formulation as Field-Deployable Medical Countermeasure

SAN ANTONIO, May 19, 2026 /PRNewswire/ -- Valion Bio, Inc. (Nasdaq: VBIO), a late-stage innate immunotherapeutics company, today announced that it presented Entolimod for acute radiation syndrome (ARS) to senior officials from the U.S. Department of War and the Biomedical Advanced Research and Development Authority (BARDA) in a joint briefing held on May 14, 2026. The session was Valion Bio's second engagement with senior Department of War officials, following the Company's April 28, 2026, Pentagon briefing on Entolimod.

We believe the cross-agency engagement reflects continued U.S. government interest in Entolimod as a differentiated medical countermeasure for radiological threats. Agency discussion included a specific interest in an oral formulation of the Company's lead candidate, which would offer operational advantages over injectable agents in mass-casualty scenarios and support broader field deployment for the warfighter. and national stockpile integration.

"This second engagement, requested by the DoW, at senior levels of the Department of War, conducted jointly with BARDA, reflects the increasing interest of Entolimod within the national radiological preparedness conversation," said Michael K. Handley, Chief Executive Officer of Valion Bio. "Cross-agency interest at this level signals that policymakers recognize the strategic importance of a differentiated, dual-tissue radiation countermeasure, and the specific focus on a potential oral formulation underscores the operational realities of field deployment and stockpile readiness that our platform is positioned to address."

Entolimod is a novel Toll-like receptor 5 (TLR5) agonist that activates NF-κB signaling to stimulate bone marrow and protect gastrointestinal tissues following ionizing radiation exposure — a dual-tissue mechanism not available in currently stockpiled countermeasures. Unlike Neupogen® (filgrastim), Neulasta® (pegfilgrastim), and Leukine® (sargramostim), which target hematopoietic recovery alone, Entolimod addresses the gastrointestinal damage that is often the limiting factor for survival at higher radiation doses. Valion Bio is working to advance both injectable and oral transmucosal formulations of Entolimod to support a broad range of deployment scenarios.

The May 14 briefing follows prior Valion Bio engagements with BARDA, the National Institute of Allergy and Infectious Diseases (NIAID), the Defense Threat Reduction Agency (DTRA), and the Company's selection for the Department of War's Tech Watch program. To date, over $140 million has been invested in the Entolimod program, including approximately $35.6 million in non-dilutive U.S. government funding. The compound has been evaluated in 42 non-human primate studies and administered to approximately 300 human subjects, demonstrating a well-characterized safety and efficacy profile.

"The current geopolitical environment continues to elevate radiological preparedness on the national security agenda, and we are seeing that reflected in the depth and frequency of our engagement with U.S. government stakeholders," Mr. Handley continued. "Our objective is straightforward: to ensure that Entolimod — and an oral formulation positioned for mass casualty and warfighter applications — is recognized and supported at the levels required to translate its differentiated profile into deployed national capability."

The Company has received FDA Fast Track and Orphan Drug designations for Entolimod in acute radiation syndrome and is advancing the program toward a Biologics License Application under the FDA's Animal Rule.

Strategic and Competitive Positioning

• Cross-agency convergence: Joint Department of War and BARDA engagement signals coordinated interest across biodefense and biomedical preparedness functions.
• Oral formulation focus: An oral medical countermeasure for ARS would expand operational deployment options for stockpiling, field use, and mass casualty response.
• Differentiated mechanism: TLR5 agonist provides dual-tissue cytoprotection versus single-target G-CSF therapies.
• Regulatory pathway: Animal Rule framework supports development for biodefense applications.
• Government validation: Approximately $35.6 million in prior federal funding and ongoing multi-agency engagement.

About Entolimod for Acute Radiation Syndrome

Entolimod (CBLB502) is a recombinant deletion variant of Salmonella FliC flagellin engineered to activate TLR5 selectively. Upon engagement, Entolimod likely triggers NF-κB-dependent signaling to stimulate G-CSF, PI3K, and IL-6 production, among others, to promote multi-tissue cytoprotection, and inhibit apoptosis in radiosensitive hematopoietic and gastrointestinal tissues. The compound has demonstrated survival benefit as both a radioprotectant and a radiomitigant in controlled non-human primate studies under the FDA's Animal Rule.

About Valion Bio, Inc.

Valion Bio, Inc. (Nasdaq: VBIO), the new corporate identity of Tivic Health Systems, Inc., is developing biologics that activate innate immune pathways for cytoprotection and modulate immune responses in conditions driven by radiation, disease, and immune dysregulation. The Company's lead candidate, Entolimod for acute radiation syndrome (ARS), has been extensively studied and has demonstrated survival benefits and improved tissue recovery in animal models under the FDA's Animal Rule. Entolimod is a novel Toll-like receptor 5 (TLR5) agonist that activates NF-κB signaling pathways to protect cells from damage and stimulate immune responses. Entolimod for ARS has received Fast Track and Orphan Drug designations from the U.S. Food and Drug Administration. Valion Bio is also advancing Entolasta, a next-generation TLR5 agonist designed for potential broader therapeutic applications, including oncology supportive care. Valion Bio's wholly owned subsidiary, Velocity Bioworks, is a full-service contract development and manufacturing organization (CDMO) that provides biomanufacturing services to third-party biotech companies. Valion Bio also leverages Velocity Bioworks' manufacturing capabilities to advance its own drug pipeline with the expected benefits of lower costs, accelerated manufacturing outcomes, and supply chain security. For more information, visit www.valionbio.com.

Forward-Looking Statements

This press release may contain "forward-looking statements" that are subject to substantial risks and uncertainties. All statements, other than statements of historical fact, contained in this press release are forward-looking statements. Forward-looking statements contained in this press release may be identified by the use of words such as "anticipate," "believe," "contemplate," "could," "estimate," "expect," "intend," "seek," "may," "might," "plan," "potential," "predict," "project," "target," "aim, "should," "will," "would," or the negative of these words or other similar expressions, although not all forward-looking statements contain these words. Forward-looking statements are based on Valion Bio, Inc.'s current expectations and are subject to inherent uncertainties, risks, and assumptions that are difficult to predict. Further, certain forward-looking statements are based on assumptions as to future events that may not prove to be accurate, including as a result of the company's interactions with and guidance from the FDA and other regulatory authorities; the continued interest of BARDA and other U.S. government agencies in Entolimod; the ability of the company to achieve the expected benefits from the acquisition of development and manufacturing assets within expected time frames or at all; changes to the company's relationship with its partners; failure to obtain FDA or similar clearances or approvals and noncompliance with FDA or similar regulations, including related to the Animal Rule; the company's future development of Entolimod or Entolasta; changes to the company's business strategy; timing and success of pre-clinical and clinical trials and study results; regulatory requirements and pathways for approval; the company's ability to successfully commercialize its product candidates in the future; changes in the markets and industries in which the company does business; consummation of any strategic transactions; the company's need for, and ability to secure when needed, additional working capital; the company's ability to maintain its Nasdaq listing; and changes in tariffs, inflation, legal, regulatory, political and economic risks. Accordingly, you are cautioned not to place undue reliance on such forward-looking statements. For a discussion of risks and uncertainties relevant to the company, and other important factors, see Valion Bio's filings with the SEC, including its Annual Report on Form 10-K for the year ended December 31, 2025, filed with the SEC on March 30, 2026, under the heading "Risk Factors", as well as the company's subsequent filings with the SEC. Forward-looking statements contained in this press release are made as of this date, and the company undertakes no duty to update such information except as required by applicable law.

Investor + Media Contact:

Rich Cockrell
CG Capital
[email protected]

SOURCE Valion Bio, Inc.