ENA Respiratory Announces Peer-Reviewed Publication of First Time in Humans and Influenza Virus Challenge Studies with the Intranasal Innate Immunomodulator INNA-051

• When compared to placebo, prophylactic administration of INNA-051 was associated with significantly increased expression of multiple host defense genes and shorter duration of infection in influenza virus-infected individuals
• Data published in ERJ Open Research, a leading open access journal in respiratory medicine

Melbourne, Australia, 18 December 2024 – ENA Respiratory, a clinical-stage pharmaceutical company developing innate immune modulators for the prevention of complications associated with respiratory viral infections in at-risk populations, announces today the publication of results of its Phase IIa proof-of-principle study with its liquid formulation of INNA-051 in ERJ Open Research, a leading research journal of the European Respiratory Society¹.

The publication also includes data from ENA Respiratory’s dose-escalation study to assess tolerability and mechanistic biomarkers following single and repeated intranasal administrations of INNA-051 in individuals aged 18-55. 

Headline results of the challenge study, conducted in the UK in 123 healthy volunteers were first announced in February 2023 with further analyses announced in September 2023.

A virus-agnostic intranasal host defence immunomodulator, INNA-051 is a potent first-in-class agonist of toll-like receptor 2/6 (TLR2/6) which plays a key role in recognizing pathogens and triggering the innate immune response. 

The data presented in the publication demonstrate:

• INNA-051 was well tolerated in both studies, with no dose-limiting toxicities identified. 
• Mechanistic biomarkers assessed in both studies demonstrated the expected engagement of pharmacology, including innate immune pathways. 
• Post hoc analysis conducted in laboratory-confirmed infected participants with low or no antibody titre against the challenge virus showed INNA-051 treatment led to significantly shorter duration of infection and increased expression of genes and pathways associated with host defence responses against influenza.

ENA Respiratory’s CEO, Christophe Demaison, PhD said: “The publication of the results of these studies demonstrates the strength of the data supporting our continued development of INNA-051 as a potentially significant new approach to protecting people at risk of real harm from serious respiratory viral infections. INNA-051 is designed to boost the body’s innate immune response – the natural first line of defence – directly at the site of infection and prevent complications relating to infection by common respiratory viruses or emerging new viruses. The newly published data confirm pre-clinical data demonstrating that INNA-051 is well-tolerated and primes virus-agnostic local innate immune responses that boost host defence pathways.”

The results of the publication announced today supported continued development of INNA-051 and the planned Phase II study to assess the potential of INNA-051 to prevent symptomatic viral respiratory infections in a community setting. ENA is completing a Phase 1b study of a dry powder formulation of INNA-051 with an anticipated shelf life of over two years at room temperature. Headline data demonstrated an acceptable safety profile and evidence of local activation of innate immune pathways in older adults. Results will be announced early in 2025.

1. ERJ Open Res 2024 Dec 9;10(6):00199-2024. doi: 10.1183/23120541.00199-2024