ENA Respiratory Attracts US$22.4m (AU$34m) to Fund Phase II Development of INNA-051 Nasal Spray Designed to Protect Against Symptomatic Viral Respiratory Infections

MELBOURNE, Australia, Oct. 22, 2025 (GLOBE NEWSWIRE) -- ENA Respiratory, a clinical-stage pharmaceutical company developing antiviral host defense enhancers to minimize the impact of symptomatic viral respiratory infections, announces today that it has raised US$22.4m (AUD$34m) in its Series B financing.

The Company welcomed new investment from the Gates Foundation and the previously announced contribution from Flu Lab. Existing investors, Brandon Capital, Uniseed and Stoic Venture Capital also participated in the round.

The new funding will support the Phase II clinical development of INNA-051, ENA’s virus-agnostic once-weekly dry powder nasal spray, which primes the natural antiviral host defences in the nose, where viruses like colds, flu, RSV and coronaviruses typically enter, enabling the body to respond more quickly when challenged. Preclinical and clinical studies conducted to date suggest that INNA-051 has the potential to shorten the duration of symptomatic infections, prevent progression to the lungs, and reduce complications.

The planned Phase II community study (‘POSITS’) will evaluate the safety, tolerability and efficacy of up to three months’ treatment with INNA-051 and assess its impact on the incidence, duration and severity of symptomatic infections caused by common respiratory viruses, including influenza, RSV, rhinovirus, and coronaviruses in young adult participants at risk of illness due to living or working in crowded environments.

The study, which is due to start shortly, will recruit up to 1,100 participants and be conducted during the 2025-2026 North American respiratory virus season. Justin Ortiz, MD, MS, Professor of Medicine at the University of Maryland’s renowned global health institution, CVDGH, and a global health physician scientist with expertise in respiratory virus protection and control, will lead as a Principal Investigator.

The INNA-051 therapy aims to reduce the incidence of complications in patients at higher risk of severe illness. Seasonal respiratory infections such as flu take a significant toll on health systems and the economy, driving costly hospitalisations and workplace absences. The impact is most significant for patients with underlying medical conditions like asthma, COPD, heart disease, kidney disease, diabetes, primary immunodeficiency and cancer, who face a much higher risk of complications, with over a million hospitalizations and up to 200,000 deaths in the U.S. in 2025 from respiratory-related viral infections.

ENA Respiratory’s CEO, Christophe Demaison, PhD said: “This funding marks a major milestone for ENA Respiratory as we advance INNA-051 into a community Phase II trial. With an international investor syndicate and ongoing support from our Australian investors, we are now in a strong position to evaluate the impact of our once-weekly powder nasal spray, which stimulates the body’s natural antiviral defences, in a community setting and moves us closer to bringing it to the patients who need it most. This is an exciting step forward in our mission to deliver a first-of-its-kind preventative option for safeguarding vulnerable populations and has the potential to ease the global burden of respiratory viruses.”

Research by the patient advocacy group Global Allergy & Airways Patient Platform, supported by ENA, found strong interest in a convenient preventative option like INNA-051 among more than 3,000 U.S. adult respondents with relevant comorbidities. A majority of those who identify themselves as high risk for hospitalisation or emergency visits due to viral respiratory infections indicated that they would use a product such as INNA-051 once a week during the winter months.

These findings highlight a clear unmet need and potential high uptake for convenient therapies that can reduce hospitalisations, keep people healthier and ease pressure on health services.

Chris Smith, PhD, Non-Executive Director, ENA Respiratory and Brandon Capital partner, said: “Brandon Capital has supported ENA Respiratory since its earliest days because we recognised the potential of INNA-051 to transform the prevention and management of respiratory infections. With this new round of funding and the upcoming Phase 2 trial in the United States, ENA Respiratory is well on its way to delivering a therapy that could protect millions of vulnerable people worldwide.”

About ENA Respiratory

ENA Respiratory is a clinical-stage pharmaceutical company tackling respiratory viral infections through the development of host defense enhancers which locally prime and boost the body’s natural first line of defense against invading pathogens. Being virus-agnostic, ENA’s approach offers a solution to protect against common and emerging respiratory viruses for which vaccines or direct-acting antivirals have limitations or do not exist.

The company’s lead product, INNA-051, is being developed as a convenient, once-a-week nasal dry powder product to reduce the impact of viral respiratory infections and prevent severe complications in at-risk populations, including the elderly, those with an underlying medical condition (including chronic lung conditions, diabetes, kidney disease, and cardiovascular disease) and individuals with occupational risk (e.g. first responders, military or essential services personnel).

INNA-051 is a potent agonist of toll-like receptor 2/6 (TLR2/6) which plays a key role in recognising pathogens and potentiating innate immune responses. With a safety profile supporting seasonal prophylaxis use, it has demonstrated accelerated virus clearance and stimulation of antiviral host defenses, including IFN Type I & III responses, in a Phase IIa proof-of-principle study using a human influenza-challenge model.

Headquartered in Melbourne, Australia, with operations in the USA, ENA’s Investors include Brandon Capital, Flu Lab, the Gates Foundation, the Minderoo Foundation, Stoic Venture Capital and Uniseed. The Company is partnered with the US COPD Foundation to support patient-focused clinical development of INNA-051 in COPD and has been awarded contracts from the U.S. Government. It is an alumni member of BLUE KNIGHT™, a joint initiative between Johnson & Johnson Innovation and BARDA designed to accelerate novel potential solutions for future pandemics.

For more information, please visit https://enarespiratory.com

About investors

Brandon Capital - https://brandoncapital.vc/

The Gates Foundation - https://www.gatesfoundation.org/

Flu Lab - https://theflulab.org/

Uniseed - https://uniseed.com/

Stoic Venture Capital - https://stoicvc.com.au/

For further information, please contact:

Media – Australia

Kirrily Davis, E: kdavis@bcpvc.com M: +61 (0)401 220228

Media – International

Charles Consultants

Sue Charles, E: sue.charles@charles-consultants.com M: +44 (0)7968 726585

Chris Gardner, E: Chris@CGComms.onmicrosoft.com M: +44 (0)7956 031077

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