Altesa BioSciences Presents New Phase 2 Vapendavir Challenge Study Results at 2026 American Society for Microbiology (ASM) Microbe Conference

New clinical findings further reinforce therapeutic potential of vapendavir as targeted approach to preventing rhinovirus-driven COPD exacerbations

WASHINGTON, June 5, 2026 /PRNewswire/ -- Altesa BioSciences, a clinical-stage pharmaceutical company dedicated to improving the lives of people with chronic lung diseases including COPD and asthma, today presented new clinical findings demonstrating vapendavir, an investigational oral rhinovirus capsid inhibitor, reduced the inflammatory response and viral load in COPD patients infected with rhinovirus in a Phase 2a challenge study. The results were shared during an oral and poster presentation at the 2026 American Society for Microbiology (ASM) Microbe Conference.

"Vapendavir treatment blunted the elevation in inflammatory mediators and viral load, providing support for reduced severity and duration of illness compared to placebo," said Dr. Katherine Laessig, Vice President, Regulatory Affairs and Quality Assurance for Altesa BioSciences. "These data further reinforce the therapeutic potential of vapendavir as a targeted approach to preventing rhinovirus-driven COPD exacerbations, a leading driver of morbidity and mortality in patients with the disease, contributing to accelerated lung function decline and diminished quality of life."

Rhinovirus is responsible for approximately 50% of acute exacerbations of COPD, yet no approved rhinovirus treatment or vaccine currently exists. The company recently enrolled its first patient in the Phase 2b CARDINAL clinical trial, which aims to demonstrate treatment of rhinovirus infections with vapendavir may improve upper and lower airway symptoms, reduce illness duration, and better maintain small airway lung function compared to placebo.

Key Findings

Rhinovirus challenge triggered increases in several immune mediators consistent with a desired innate antiviral response, including IFN-α2a, IL-29, IP-10, and GM-CSF. Compared to placebo, vapendavir treatment reduced key inflammatory mediators, including:

• Peak IFN-α2a levels by approximately 38%
• Peak IP-10 levels by approximately 50%
• Peak IL-29 levels by approximately 67%

About Vapendavir

Vapendavir, taken orally in pill form, is a broad-spectrum antiviral investigational oral drug – preventing the virus from both entering human cells as well as reproducing. It exhibits potent activity across 97% of rhinoviruses and other respiratory enteroviruses. The trial's objective is to assess improvement in respiratory symptoms using established patient-reported outcomes, with additional endpoints evaluating time to symptom resolution, quality of life, healthcare resource utilization, and lung function. While the immediate focus is on COPD, vapendavir has potential for broader application in other high-risk respiratory populations, including people with asthma.

About the CARDINAL Study

The CARDINAL clinical trial is a Phase 2b multinational randomized placebo-controlled study in COPD patients experiencing rhinovirus infections that will enroll 900 people with COPD in the US and UK. The trial was designed to reflect real-world care models, proactively identifying and supporting those at greatest risk. Participants will be closely monitored over time and, upon development of rhinovirus infection, will be randomized to receive one of two doses of vapendavir or placebo. The trial's primary objective is to assess improvement in respiratory symptoms using established patient-reported outcomes, with additional endpoints evaluating time to symptom resolution, quality of life, healthcare resource utilization, and lung function. To learn more, visit www.COPDCardinalStudy.com/join. NCT07610395

About Altesa BioSciences

Altesa BioSciences is a clinical-stage pharmaceutical company, led by global experts in respiratory medicine and infectious diseases. We are dedicated to improving the lives of people with chronic lung diseases, like COPD and asthma, by treating the principal cause of exacerbations and pathological inflammation – viral respiratory infections. In addition to advancing vapendavir, our lead medicine, we advocate for improved access to modern respiratory diagnostics and therapeutics in underserved communities. www.altesa.com

Media Contact: Peg Rusconi
Email: [email protected]

SOURCE Altesa Biosciences Inc.