MELBOURNE, Australia, May 11, 2026 (GLOBE NEWSWIRE) — ENA Respiratory, a clinical-stage pharmaceutical company developing antiviral host defence enhancers to minimize the impact of symptomatic viral respiratory infections, today announces the successful completion of Part A of its Phase IIa community study of INNA-051, and progression to Part B.
INNA-051 is a 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. INNA-051 therapy aims to reduce the incidence of complications in patients at higher risk of severe illness.
The ‘POSITS’ study (https://clinicaltrials.gov/study/NCT07222670) is evaluating the safety, tolerability and efficacy of up to three months’ treatment with INNA-051 and assessing 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.
In Part A, the study recruited 200 participants across five sites in the USA, including the Center for Vaccine Development and Global Health (CVD) at the University of Maryland, Baltimore, the Naval Medical Research Command (NMRC) Clinical Trials Center, Bethesda, Maryland and three Accellacare clinical sites in North Carolina. Four weeks of dosing have now been completed with no safety concerns identified.
The Safety Review Committee has endorsed progression to Part B following a safety review of Part A. Part B will recruit 900 participants during the next North American respiratory virus season, with participants dosed for three months. Recruitment will continue to target those in severely crowded households, residents of university housing, military personnel living in barracks, childcare center workers and/or those living with or caring for a child aged 10 or less attending school or day care (https://enarespiratory.com/inna-051/clinical-trials/).
ENA Respiratory’s Medicine Development Leader, Ruth Tal-Singer, PhD said: “The successful completion of the first part of this Phase IIa study and the Safety Review Committee’s endorsement to progress to larger scale and longer dosing represent important milestones in the development of INNA-051. We look forward to continuing this productive collaboration with our excellent clinical partners as we advance this program to bring this important new therapy option closer to reaching those in need.”
About ENA Respiratory
ENA Respiratory is a clinical-stage pharmaceutical company tackling respiratory viral infections through the development of host defence enhancers which locally prime and boost the body’s natural first line of defence 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 defences, 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
Follow us on LinkedIn: https://www.linkedin.com/company/enarespiratory-pty-ltd/
For further information, please contact:
Media – Australia
Ruth Heenan, E: rheenan@bcpvc.com M: +61 (0)416 565 332
Media – International
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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
