Ethris GmbH, a clinical-stage biotechnology company pioneering next-generation RNA therapeutics and vaccines, today announced that the first patient has been treated in a Phase 2a clinical trial investigating ETH47, Ethris’ lead mRNA-based antiviral candidate. The study will assess the ability of intranasal ETH47 to reduce asthma-related symptoms following a rhinovirus challenge in adults with asthma. ETH47 encodes interferon lambda (IFNλ), a protein crucial for viral immunity in the airways. It is designed to target viral triggers of asthma exacerbations, one of the most common causes of acute symptoms in patients with asthma.

The start of the Phase 2a clinical trial (ISRCTN21576805) builds on positive data from the Phase 1 trial (ISRCTN15391202) where ETH47 demonstrated favorable safety and tolerability at all tested doses in healthy volunteers. The trial confirmed targeted activity in the respiratory tract, with robust local induction of IFNλ and activation of antiviral genes, with no systemic exposure to mRNA, IFNλ, or the lipidoid nanoparticle, thereby minimizing the risk of off-target effects.

“Dosing the first patient in our Phase 2a trial for ETH47 marks a defining moment for Ethris, as we advance our lead candidate further into clinical development and continue to validate the potential of Ethris’ innovative platform,” said Dr. Thomas Langenickel, Chief Medical Officer of Ethris. “ETH47 stands out as a highly promising candidate with a novel mechanism of action designed to directly strengthen the body’s antiviral defenses in the airways. By targeting viral infections upstream, ETH47 has the potential to fundamentally change the way asthma is managed and reduce the burden of acute attacks. The trial gives us the opportunity to validate a new paradigm of care and, if successful, set a new standard for asthma treatment and open doors for broader advances in respiratory disease.”

Sebastian Johnston, Professor of Respiratory Medicine at the Imperial College London and Director & Chief Medical Officer of VirTus Respiratory Research Ltd, an internationally recognized expert in the field of asthma and viral respiratory infections and one of Ethris’ scientific advisors, added, “After more than three decades investigating the role of respiratory viruses in asthma, it is clear that we need new approaches to address the underlying triggers of asthma exacerbations. Most therapies today focus on managing symptoms or reducing inflammation. There remains a significant unmet need for interventions that directly target viral triggers and boost antiviral defenses in the airways. This is precisely where innovative new approaches like ETH47 could make a real difference for patients and healthcare systems.”

The Phase 2a clinical trial is a randomized, double-blind, placebo-controlled study being conducted by VirTus Respiratory Research Ltd at St. Mary’s Hospital, London, UK. It will enroll 50 adult patients with asthma who will undergo a rhinovirus challenge and will then be equally randomized to receive either ETH47 or placebo. The primary endpoint will evaluate the impact of ETH47 on respiratory symptoms, as measured by the Lower Respiratory Symptoms Score (LRSS) – a commonly used, standardized survey completed by participants twice daily. The primary objective is to assess whether ETH47 can help restore respiratory health in asthmatic patients, bringing them closer to the level observed in healthy individuals.

After the successful completion of this trial, Ethris plans to progress ETH47 into a broader Phase 2b study, further evaluating its potential to reduce asthma exacerbations and improve patient outcomes.

About ETH47

ETH47 is Ethris’ first-in-class mRNA-based product candidate encoding interferon lambda (IFNλ) that was developed using the company’s Stabilized Non-Immunogenic mRNA (SNIM®RNA) platform, and uniquely designed to be administered locally to the respiratory tract through inhalation or nasal spray using Ethris’ proprietary Stabilized NanoParticle (SNaP®) LNP platform. ETH47 is meant to induce a mucosal innate immune defense response at virus entry sites as well as inhibit viral replication. ETH47’s versatile, virus- and mutation-independent mode of action has the potential to broadly address seasonal and emerging respiratory virus infections, including virus-driven exacerbation of chronic respiratory diseases such as asthma.

About Ethris

Ethris, a clinical-stage biotechnology company, has paved a new path from genes to therapeutic proteins, using its proprietary RNA and lipidoid nanoparticle technology platform to discover, design and develop innovative therapies. With more than a decade as an mRNA pioneer, Ethris is a global leader in delivering stabilized mRNAs directly to the respiratory system via optimised formulation and nebulisation technologies. The company is rapidly advancing its mRNA pipeline of immuno-modulation, protein replacement therapies, and differentiated vaccines, with the ultimate goal of improving patients’ lives.

For more information, visit www.ethris.com

View source version on businesswire.com: https://www.businesswire.com/news/home/20250805027802/en/