Edesa Biotech Celebrates Success in Phase 3 ARDS Treatment Trial

Edesa Biotech, Inc. announced promising results from a Phase 3 clinical trial evaluating its drug candidate, paridiprubart (EB05), aimed at treating Acute Respiratory Distress Syndrome (ARDS), a severe form of respiratory failure. The data, released on October 28, 2025, indicate that paridiprubart significantly improved patient outcomes, achieving both primary and secondary endpoints with statistical significance.

The Phase 3 study demonstrated a substantial reduction in mortality rates among patients treated with paridiprubart. Specifically, the drug showed a 39% risk of death at 28 days in patients receiving paridiprubart alongside standard of care, compared to 52% for those on placebo. This represents a 13% absolute improvement in survival, translating to a 25% relative reduction in mortality risk (n=104; p<0.001). The positive outcomes continued to be evident at 60 days, with a similar pattern observed.

In addition to mortality reduction, patients receiving paridiprubart exhibited a 41% higher relative rate of clinical improvement, indicating that they no longer required invasive mechanical ventilation (IMV) or organ support by Day 28. The study’s safety assessments, which evaluated over 275 subjects, confirmed that the drug was well-tolerated and consistent with previously observed safety profiles.

Edesa Biotech’s Chief Executive Officer, Par Nijhawan, MD, expressed optimism regarding the trial’s results. He highlighted that the data underscore the potential of paridiprubart to transform treatment outcomes for patients suffering from ARDS. “The findings provide important validation of our therapeutic approach and support the use of paridiprubart as a standard treatment for ARDS, and potentially for chronic respiratory conditions,” he stated.

Study Details and Methodology

The clinical trial involved participants from 38 hospitals across the USA, Canada, and Colombia. Eligible patients were aged 18 years or older and required IMV upon hospitalization. They were randomly assigned to receive either paridiprubart (15 mg/kg, maximum dose of 1400 mg, n=56) or a placebo (n=48) in conjunction with standard of care.

Efficacy outcomes included mortality at both 28 days and 60 days, as well as a decrease of ≥2 points on the WHO COVID-19 Severity Scale at Day 28. Notably, enrollment was discontinued early for business reasons, although the demographics and baseline characteristics of the two treatment groups were comparable.

Understanding ARDS and Future Implications

Acute Respiratory Distress Syndrome is characterized by an exaggerated immune response that leads to inflammation and lung injury, severely impairing oxygenation. The condition accounts for approximately 10% of intensive care unit admissions globally, affecting over 3 million patients each year. Currently, treatment options are limited, primarily involving supplemental oxygen and mechanical ventilation.

Paridiprubart represents a novel class of host-directed therapeutics (HDTs) designed to modulate the immune response to various health threats, including infectious diseases and other emergencies. By inhibiting toll-like receptor 4 (TLR4), paridiprubart can potentially address these challenges regardless of the specific cause.

Edesa Biotech’s development program for paridiprubart, including this Phase 3 study, is supported by funding from the Government of Canada’s Strategic Innovation Fund. Additionally, the drug is being evaluated in the U.S. government’s “Just Breathe” study, which focuses on innovative therapeutics for hospitalized patients with ARDS.

As the landscape of ARDS treatment continues to evolve, Edesa Biotech’s promising results position paridiprubart as a potential game-changer in improving survival rates and overall patient outcomes in critical care settings.