New Preventative Nasal Spray Reduces Viral Replication by Up to 96% in COVID-19 Challenge Study

A new preventative nasal spray treatment that has been shown to reduce viral replication by up to 96% in a COVID-19 challenge study could protect people from the SARS-CoV-2 virus and prevent its transmission.

The novel product, INNA-051, has been developed by Ena Therapeutics (Melbourne, Australia) to boost the natural human immune system to fight common colds and flu. INNA-051 has proved remarkably successful in tests by reducing COVID-19 viral replication by up to 96% in a gold-standard animal study. The INNA-051 compound works by stimulating the innate immune system, the first line of defense against the invasion of pathogens into the body. By boosting the immune response in this way with INNA-051 prior to infection, the ability of the COVID-19 virus to infect the animals and replicate was dramatically reduced the study showed. The study provides evidence that INNA-051 can be used as a stand-alone method of antiviral preventative therapy, complementary to vaccine programs.


INNA-051, a synthetic small molecule, would be self-administered via an easy-to-use nasal spray, taken once or twice a week, with the treatment taking almost immediate effect. If human trials are successful and, given the unprecedented need for drugs to combat COVID-19, the prophylactic immune modulation therapy could be rapidly manufactured at scale and be available for use soon.

"We've been amazed with just how effective our treatment has been. By boosting the natural immune response of the ferrets with our treatment, we've seen a rapid eradication of the virus," said Ena Respiratory Managing Director, Dr Christophe Demaison. "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."

"This is a significant development as the world races to find a solution to halt COVID-19 transmission and infection of at risk-populations," said Professor Roberto Solari a respiratory specialist, advisor to Ena Respiratory and visiting Professor at Imperial College London. "Most exciting is the ability of INNA-051 to significantly reduce virus levels in the nose and throat, giving hope that this therapy could reduce COVID-19 transmission by infected people, especially those who may be pre-symptomatic or asymptomatic and thus unaware they are infectious."

Related Links:
Ena Therapeutics