Virax Biolabs Posts Positive Early Clinical Data for ViraxImmune™ in Long COVID and Post-Acute Infection Syndromes

Virax Biolabs Group Limited (NASDAQ: VRAX) (“Virax” or the “Company”) today announced encouraging early pilot results for ViraxImmune™, its blood-based test under development for Long COVID, myalgic encephalomyelitis/chronic fatigue syndrome (“ME/CFS”) and related post-acute infection syndromes (“PAIS”). In the pilot dataset, ViraxImmune™ clearly separated PAIS patients from healthy controls, hitting 88% specificity and 92% positive predictive value (“PPV”) — early performance metrics that, according to Virax, justify continued development and progression into larger clinical validation.

Drawing on estimates from the CDC, the RECOVER Initiative and other peer-reviewed and public-health sources, Virax projects that as many as 21 million U.S. adults may currently live with Long COVID and related PAIS conditions, while roughly 2.5 million new cases emerge each year. Consequently, the Company sees a substantial U.S. testing opportunity in a space where clinicians typically assess patients through symptoms and exclusion rather than objective immune biomarkers — precisely the gap ViraxImmune™ aims to fill.

Highlights:

• In the pilot dataset, ViraxImmune™ clearly distinguished PAIS patients from healthy controls, achieving 88% specificity and 92% positive predictive value (“PPV”).
• To date, ViraxImmune™ has been evaluated in more than 120 subjects across the Company’s ongoing UK clinical study in Long COVID, ME/CFS and related post-acute infection syndromes.
• Looking ahead, Virax is preparing its next major development milestone: a larger clinical validation analysis covering 300 additional previously collected samples, with analysis beginning in Q4 2026 and results expected in Q1 2027.
• Overall, the findings support Virax’s intended U.S. market-entry strategy — an initial PAIS-focused U.S. Laboratory Developed Test (“LDT”) route, followed over time by broader in vitro diagnostic (“IVD”) development.

Addressing a Major Unmet Diagnostic Need

If larger studies validate these early findings, ViraxImmune™ could emerge as one of the first objective immune-profiling tools built specifically for Long COVID, ME/CFS and related post-acute infection syndromes. As a result, Virax believes the test could anchor a differentiated diagnostic strategy in an area of significant unmet need, with potential applications spanning patient stratification, clinical decision-making, longitudinal monitoring and therapeutic development.

“These early pilot data mark an important step in the development of ViraxImmune™ as a potential objective immune-profiling test for Long COVID, ME/CFS and related post-acute infection syndromes,” said James Foster, Chairman and Chief Executive Officer of Virax Biolabs. “The observed separation between patients and healthy controls, together with encouraging early performance metrics, reinforces our confidence that ViraxImmune™ can address a major unmet diagnostic need as we move toward our planned U.S. LDT-first route to market.”

Dr. Sean Knight, MD, PhD, Principal Investigator at the Lydia Becker Institute of Immunology and Inflammation, University of Manchester, and Consultant Respiratory Physician at Northern Care Alliance NHS Foundation Trust, added: “Patients with Long COVID, ME/CFS and related post-acute infection syndromes often face lengthy diagnostic journeys and limited objective testing options. Objective immune profiling may improve how clinicians assess, stratify and monitor these patients over time. These early pilot findings are encouraging and support further clinical validation of ViraxImmune™.”

Investor Webcast

Virax will host an investor webcast today, May 26, 2026, at 4:15 p.m. ET to walk through the early ViraxImmune™ dataset, discuss the clinical and commercial implications of the results, and outline the Company’s planned path toward larger clinical validation, assay finalization and U.S. market entry. Interested parties may register for the webcast at the provided link, and a replay will follow the event.

ViraxImmune™ remains in development and is not approved for diagnostic use in any jurisdiction. The VRX003 observations are preliminary and are intended to guide ongoing assay development and future clinical validation planning.

About Virax Biolabs Group Limited

Virax Biolabs Group Limited is a biotechnology company focused on detecting immune responses to and diagnosing viral diseases. The Company is developing T cell-based test technologies designed to power an immunology profiling platform. T cell testing may ultimately support applications in post-acute infection syndromes, including Long COVID, as well as other chronic conditions linked to immune dysregulation.

For more investor relations information, visit www.ir.viraxbiolabs.com.