ENA Respiratory Initiates Phase II Trial of INNA-051 Nasal Spray for Viral Respiratory Infection Prevention
核心洞察
ENA Respiratory (搜索) has dosed the first participants in its Phase II POSITS study evaluating INNA-051, a virus-agnostic nasal spray designed to prime natural antiviral defenses against respiratory infections.
The study will recruit up to 1,100 participants at high risk for viral exposure, with an initial 200-participant safety phase followed by a 900-participant efficacy phase next season.
INNA-051 targets toll-like receptor 2/6 (搜索) and has demonstrated accelerated virus clearance in previous Phase IIa studies using human influenza (搜索)-challenge models.
ENA Respiratory (搜索) has announced the dosing of first participants in its Phase II community study of INNA-051, a virus-agnostic nasal spray designed to enhance natural antiviral host defenses. The Melbourne-based clinical-stage pharmaceutical company initiated the POSITS study at the Center for Vaccine Development and Global Health at the University of Maryland, Baltimore, with additional recruitment at the Naval Medical Research Command (搜索) Clinical Trials Center in Bethesda, Maryland.
Novel Approach to Viral Respiratory Protection
INNA-051 represents a unique therapeutic approach as a once-weekly, dry powder nasal spray that primes natural antiviral host defenses in the nose, where viruses like colds, flu, RSV (搜索) and coronaviruses (搜索) typically enter the body. The therapy enables the body to respond more quickly when challenged by viral pathogens and aims to reduce the incidence of complications in patients at higher risk of severe illness.
The drug functions as a potent agonist of toll-like receptor 2/6 (搜索) (TLR2/6 (搜索)), which plays a key role in recognizing pathogens and potentiating innate immune responses. Previous Phase IIa proof-of-principle studies using a human influenza (搜索)-challenge model demonstrated that INNA-051 accelerated virus clearance and stimulated antiviral host defenses, including IFN Type I & III responses.
Study Design and Participant Population
The POSITS study will evaluate the safety, tolerability and efficacy of up to three months' treatment with INNA-051, assessing its impact on the incidence, duration and severity of symptomatic infections caused by common respiratory viruses, including influenza (搜索), RSV (搜索), rhinovirus (搜索), and coronaviruses (搜索) in young adult participants at risk of illness due to living or working in crowded environments.
The study will recruit up to 1,100 generally healthy male and female participants who are at increased risk for exposure to viral respiratory infections (搜索). The trial is structured in two phases: an initial 200-participant safety Phase A being conducted during the current North American respiratory virus season, with weekly dosing for four weeks, followed next season by a 900-participant Phase B with participants being dosed for three months.
Recruitment targets include those in severely crowded households, residents of university housing, military personnel living in barracks, childcare center workers and those living with or caring for a child aged 10 or less attending school or day care.
Addressing Significant Medical Need
Viral respiratory infections (搜索) represent a major global health problem, with the impact being most significant for patients with underlying medical conditions such as asthma (搜索), COPD (搜索), heart disease (搜索), kidney disease (搜索), diabetes (搜索), primary immunodeficiency (搜索) and cancer (搜索), who face a much higher risk of complications.
"There were over a million hospitalizations and up to 200,000 deaths in the U.S. in 2025 from respiratory-related viral infections in such patients last year," said Christophe Demaison, PhD, CEO of ENA Respiratory (搜索). "By boosting the body's natural host defense pathways INNA-051 could offer a new option for millions of vulnerable patients worldwide and this study is an opportunity to add significantly to our evidence of its potential."
Clinical Development Strategy
Demaison emphasized the significance of the study initiation: "The start of the POSITS study is an important next step for ENA Respiratory (搜索) and for the development of INNA-051. Our previous pre-clinical and clinical work has shown INNA-051 to have the potential to shorten the duration of symptomatic infections, prevent progression to the lungs, and reduce complications."
INNA-051 is being developed as a convenient, once-a-week nasal dry powder product to reduce the impact of viral respiratory infections (搜索) and prevent severe complications in at-risk populations, including the elderly, those with underlying medical conditions, and individuals with occupational risk such as first responders, military or essential services personnel.
The company's virus-agnostic approach offers a potential solution to protect against common and emerging respiratory viruses for which vaccines or direct-acting antivirals have limitations or do not exist. With a safety profile supporting seasonal prophylaxis use, INNA-051 represents a novel therapeutic strategy in the respiratory infection prevention landscape.