Altesa BioSciences Presents Findings Demonstrating Beneficial Effects of vapendavir for Treating Rhinovirus Infections in COPD Challenge Study

Treatment improved patient reported outcomes, reduced viral load, and maintained lung function compared to placebo; Multi-center, international trial slated for 2026

AMSTERDAM, Sept. 28, 2025 /PRNewswire/ -- Dr. Sebastian Johnson -- Professor of Respiratory Medicine and Allergy at the National Heart and Lung Institute, Imperial College London -- presented positive findings demonstrating the beneficial effects of Altesa BioSciences' oral drug, vapendavir, for preventing respiratory deteriorations caused by rhinovirus infections in COPD patients.  The findings were presented in a late breaker session at the European Respiratory Society (ERS) Congress 2025 meeting, vapendavir's positive findings were from a human challenge study conducted in 40 participants with Stage 2 COPD who were intranasally infected with rhinovirus and then treated with either vapendavir or placebo after the onset of respiratory symptoms for 7 days. Professor Johnston observed: "Patients fear these infections because they know it will worsen their symptoms and quite frequently, they end up in hospital. This is the first study to show a positive outcome with an antiviral drug that will treat over half of common colds, and COPD patients will be very enthusiastic to have this drug in their home if and when it gets to this stage -- which I sincerely hope it does."

Dr. Brett Giroir, Chief Executive Officer of Altesa BioSciences and former US Assistant Secretary for Health and former Acting FDA Commissioner said, "Due to these very encouraging results, Altesa plans to begin enrollment in a large, multicenter, multinational Phase 2/3 randomized placebo- controlled trial in Stage 2,3, and 4 COPD patients experiencing rhinovirus infections beginning in early 2026."

Commenting further on Prof. Johnston's findings, Dr. Katharine Knobil, Chief Medical Officer of Altesa and former Chief Medical Officer of GSK said, "his is the first study that has shown that an antiviral for rhinovirus infection, the most common cause of COPD exacerbations, can have a positive impact on upper and lower respiratory symptoms in these vulnerable patients. This effect has the potential to reduce the severity of COPD exacerbations or even prevent exacerbations of their disease, which can have devastating consequences."

Noting that the official theme for ERS Congress 2025 is 'Respiratory health around the globe', Dr. Knobil added: "Vapendavir demonstrated a consistent beneficial effect across numerous important parameters -- suggesting this medicine could become a transformative new therapy for the more than sixteen million Americans and hundreds of millions around the world who daily suffer with COPD."

Dr. Giroir pointed out that rhinovirus infection is the most common cause of exacerbations among COPD patients -- accounting for nearly half of these flare-ups -- and said Altesa's vision is to treat these viral infections with a safe and effective oral pill, "which will stop the virus in its tracks before it can cause devastating consequences for patients." he concluded. "If we are successful, not only will we save lives and improve the quality of life for patients, but also potentially save billions of dollars in health care expenditures each year."

Study details

Altesa's rhinovirus challenge study was conducted by VirTus Respiratory Research Ltd in London, United Kingdom, co-led by Professor Sebastian Johnston and Dr Michael Edwards. With its collaborators at Imperial College London and St. Mary's Hospital, VirTus is the only company in the world to conduct such studies in COPD -- and Johnston has done so safely since 2006.

Unlike many other challenge studies for other viral illnesses, our challenge model was designed to mimic as closely as possible the experience of COPD patients in the real world, starting treatment only when their symptoms start to worsen. Participants did not receive vapendavir or placebo until they self-reported the onset of symptoms; furthermore, they were not isolated or confined in the clinic during the study -- they went home after visits to live in their normal environment.

Participants in the study had a diagnosis of Stage 2 COPD and met specific criteria to ensure that the rhinovirus infection would only result in a temporary worsening of their illness. Participants generally developed an upper respiratory illness on the second day after the challenge, followed by worsening of lower respiratory symptoms. Vapendavir treatment began after the onset of clinical illness and continued for a total of seven days. Vapendavir was well tolerated with no serious adverse events and no withdrawals due to adverse events. More detailed results from Altesa's Challenge Study will be submitted for publication in a peer-reviewed journal.

About vapendavir

Vapendavir is an oral medicine in development by Altesa BioSciences. Recently, Altesa announced that vapendavir improved symptoms and viral load in COPD patients experimentally challenged with rhinovirus infection. Vapendavir is now in late-stage clinical development, and if approved, vapendavir has the potential to prevent up to 50% of COPD exacerbations, improving quality of life and longevity, saving billions, and reducing the need for costly monthly immune modifying injections that may have long term side effects.

About Altesa BioSciences, Inc.

Altesa BioSciences is a clinical-stage pharmaceutical company, led by global experts in respiratory medicine and infectious diseases, 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.

Media Contact: Mia Heck
Email: MHeck@altesa.com
Cellular: 210.284.0388

SOURCE Altesa Biosciences Inc.