ONDINE BIOMEDICAL INC.

("Ondine Biomedical", "Ondine", or the "Company")

Microbiome research supports use of Steriwave

Ondine Biomedical demonstrated that photodisinfection does not harm the nasal microbiome

Research presented by Canadian life sciences company, Ondine Biomedical Inc. (LON:OBI), at the prestigious SPIE Photonics West conference in San Francisco, California shows that treatment with its Steriwave® Nasal Photodisinfection System significantly reduces pathogens in the nose - a reservoir for bacteria - yet does not produce long-term adverse effects on the nasal microbiome.[*]

Upon analysis of nasal swab samples, the research demonstrated an immediate and highly significant (99.9+% ~3 log₁₀) reduction in viable bacterial cells and number of species, sustained for at least 24 hours. Importantly, within a week, the microbiome rebounded to its original diversity and quantity. These findings support Steriwave as an efficient, potent, short-acting, and non-selective method of nasal decolonization, with the advantage of rapid recovery of the native microbiome post-treatment.

In comparison to antibiotics, the study demonstrated that Steriwave is far less likely to significantly alter the native microbiota. The antibiotic mupirocin, commonly used for nasal decolonization, has been shown to affect microbiota diversity for over 6 months, allowing disease-causing pathogens like Staphylococcus aureus to colonize the nose before beneficial species, putting patients at increased risk of infection.[1] Steriwave, in contrast, offers a more favourable profile with the study results showing a reduced risk of long-term microbiome disruption, as the microbiome consistently returns to baseline.

Notably, minimizing microbiome disruption is also important in safeguarding immune function, reducing vulnerability to infectious diseases by maintenance of a microecological environment populated by beneficial commensal microbes instead of disease-causing species.[2] The oral research presentation, delivered by Ondine's Director of Research and Development, Dr. Caetano Sabino, reported results from an exploratory study involving 35 healthy volunteers, examining the responses of the nasal microbial population after Steriwave treatment.

Organized by SPIE, the international society for optics and photonics, SPIE Photonics West is the largest annual event for optic and photonic technologies and one of the world's largest scientific conferences. Ondine's oral presentation, titled "Microbiome Analysis of Photodynamic Nasal Decolonization," was delivered at 10:20am on Tuesday 30 January, as part of the "Photonic Diagnosis, Monitoring, Prevention, and Treatment of Infections and Inflammatory Diseases" session.

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About SPIE Photonics West

SPIE Photonics West is the optics and photonics industry's preeminent annual conference and exhibition and is one of the largest scientific conferences in the world. Its scope covers all areas regarding the use of light for scientific and technological applications. The conference brings together tens of thousands of researchers, innovators, engineers, and business leaders from across the globe for an engaging week of research sharing, collaboration forming, and innovation-inspiring exchanges. The week will include more than 4,500 technical presentations as well as showcasing over 1,200 companies in three focused exhibitions.

About Ondine Biomedical Inc.

Ondine Biomedical Inc. is a Canadian life science company innovating in the field of photodisinfection therapies. Ondine has a pipeline of investigational products, based on its proprietary photodisinfection platform, in various stages of development. Ondine's nasal photodisinfection system has a CE mark in Europe and the UK and is approved in Canada and several other countries under the name Steriwave®. In the US, it has been granted Qualified Infectious Disease Product designation and Fast Track status by the FDA and is currently undergoing clinical trials for regulatory approval. Products beyond nasal photodisinfection include therapies for a variety of medical indications such as chronic sinusitis, ventilator-associated pneumonia, burns, and other indications.

About Nasal Photodisinfection

Ondine's Steriwave® Nasal Photodisinfection System is a patented technology using a proprietary light-activated antimicrobial (photosensitizer) to destroy pathogens. The photodisinfection treatment is carried out by a trained healthcare professional and is an easy to use, painless, two-step process. The photosensitizer is applied to each nostril using a nasal swab, followed by illumination of the area with a specific wavelength of red laser light for less than five minutes. The light activates the photosensitizer, causing an oxidative burst that is lethal to all types of pathogens. A key benefit of this approach, unlike with antibiotics, is that pathogens do not develop resistance to the therapy.

Nasal decolonization with antibiotics is already standard practice in many hospitals prior to surgery, as pathogens in a patient's nasal cavities are a major cause of surgical site infections (SSIs). Nasal decolonization is recommended in the 2016 WHO Global guidelines for the prevention of surgical site infections,[3] and the Society for Healthcare Epidemiology of America (SHEA) guidelines, published in May 2023, recommend nasal decolonization for major surgical procedures.[4] However, there is a growing need to reduce antibiotic use and find non-antibiotic methods of nasal decolonization as resistance rates have been reported as high as 81%.[5]