The novel nasal spray, INNA-051, is being developed by Australian biotech Ena Respiratory. The company has published its animal study, led by Public Health England’s Deputy Director Professor Miles Carroll, on biomedical pre-publication research site medRxiv.
The researchers note that INNA-051 ‘significantly reduced’ COVID-19 virus levels in the nose and throat. A nasal administration delivered once or twice a week could be used to prevent infection in at-risk populations and healthcare workers, says the biotech. Consequently, the spray could act in a preventative manner and reduce COVID-19 transmission by pre-symptomatic or asymptomatic people.
Boosting natural immune response
INNA-051 was in development before the outbreak of the coronavirus pandemic, working towards broader respiratory viral epidemics such as colds and the flu. Unlike vaccines – which are targeted towards a specific strain – INNA-051 is designed to be effective for all respiratory infections.
Ena Respiratory has now used a ferret challenge model to show that five days after exposure to high levels of COVID-19, animals treated with INNA-051 had ‘statistically significant’ reduction of virus in throat swabs and nasal washes (96% and 93% reduction respectively) compared to untreated animals.
INNA-051 is a synthetic pegylated TLR2/6 agonist. It has been developed for topical delivery to the airways via regular application of the nasal spray to target the primary site of most respiratory virus infections, including COVID-19, influenza and rhinovirus. The therapy is based on discoveries made by Professorial Fellow David Jackson (Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, University of Melbourne) and his team.
The INNA-051 compound works by stimulating the innate immune system, the first line of defence against the invasion of pathogens into the body. By boosting an immune response with INNA-051 prior to infection, the ability of the COVID-19 virus to infect the animals and replicate can be ‘dramatically reduced’, according to the PHE study. By targeting nose and throat cells, this reduces the amount of virus produced and in turn the amount of virus entering the lungs.
INNA-051 could be used as a stand-alone method of antiviral preventative therapy, complementary to vaccine programs.
Dr Christophe Demaison, Ena Respiratory Managing Director, said. "By boosting the natural immune response of the ferrets with our treatment, we've seen a rapid eradication of the virus.
"If humans respond in a similar way, the benefits of treatment are two-fold. Individuals exposed to the virus would most likely rapidly eliminate it, with the treatment ensuring that the disease does not progress beyond mild symptoms. This is particularly relevant to vulnerable members of the community. In addition, the rapidity of this response means that the infected individuals are unlikely to pass it on, meaning a swift halt to community transmission."
Ena Respiratory has raised $11.7m AUS ($8.24m USD) from Australian investors and - subject to successful toxicity studies and regulatory approval – believes it can be ready to test INNA-051 in human trials in less than four months. It says the prophylactic immune modulation therapy could be rapidly scaled up for manufacture.
Investment and support in developing the novel therapy has been led from the Australian Medical Research Commercialisation Fund (MRCF), Australia's largest life science investment fund managed by Brandon Capital, with co-investment from university commercialisation fund Uniseed.
The company is now seeking additional funding to accelerate the nasal spray's clinical development and global distribution.