Results in a population of 278 patients affirm statistically significant mortality reductions
Benefits observed across severity groups and in subjects with serious comorbidities
Company files provisional patent applications for sepsis, acute kidney injury and pneumonia
Strategic collaborations to support late-stage development and commercialization being evaluated
Study results selected for oral presentation at ATS 2026 conference

TORONTO, Feb. 24, 2026 (GLOBE NEWSWIRE) -- Edesa Biotech, Inc. (NASDAQ:EDSA), a clinical-stage biopharmaceutical company focused on developing host-directed therapeutics for immuno-inflammatory diseases, announced today positive additional data from a Phase 3 study of paridiprubart.

The results represent a broader, 278-patient population, which includes both previously reported 104 patients requiring invasive mechanical ventilation (IMV) as well as 174 non-IMV patients. Across this full population, the company's first-in-class anti-TLR4 antibody demonstrated a statistically significant reduction in 28-day mortality. Treatment benefits were consistent across severity groups and in patients with serious comorbidities.

Key Findings

The primary endpoint was achieved for the full treatment population of 278 randomized subjects. Paridiprubart reduced adjusted 28-day mortality to 24% from 33%, a 27% relative reduction in the risk of death (p<0.001). In addition, subjects receiving paridiprubart demonstrated a higher relative rate of clinical improvement by Day 28. Paridiprubart or placebo were provided in addition to standard of care treatments (SOC).

In an exploratory analysis of a milder population of 174 randomized patients who did not meet the study's IMV-based inclusion criteria, paridiprubart + SOC reduced adjusted 28-day mortality to 15% from 23% (placebo + SOC), a 35% relative reduction in the risk of death (p<0.05).

Edesa also reported that exploratory analyses across a patient population of up to 108 randomized subjects consistently demonstrated reduced adjusted mortality for paridiprubart + SOC vs. placebo + SOC at 28 days in subjects with clinically important comorbidities:

Acute Kidney Injury: 35% relative reduction (35% paridiprubart vs. 53% placebo; p<0.05, n=48)
Sepsis: 36% relative reduction (40% paridiprubart vs. 63% placebo; p<0.05, n=41)
Pneumonia: 30% relative reduction (35% paridiprubart vs. 49% placebo; p<0.05, n=108)

Overall rates of adverse events, serious adverse events, infections and treatment discontinuations were low and similar between the paridiprubart and placebo groups. The safety profile was consistent with prior clinical exposures, with more than 400 patients now having received paridiprubart.

Based in part on these positive results, Edesa has filed provisional patent applications with the United States Patent and Trademark Office covering the use of paridiprubart in the treatment of sepsis, acute kidney injury and pneumonia. The company's core composition-of-matter patents extend into the 2030s.

Par Nijhawan, MD, Chief Executive Officer of Edesa Biotech, said that the results announced today align with the central role of TLR4 in hyperinflammatory ARDS (Acute Respiratory Distress Syndrome) and demonstrate consistent benefit across high-mortality etiologies.

"The consistency of mortality reduction and clinical improvement across all 278 randomized patients, including less severe patients as well as those with ARDS complicated by acute kidney injury, sepsis and pneumonia, underscores the versatility and transformative potential of paridiprubart to address multiple critical unmet medical needs," said Dr. Nijhawan. "We are advancing regulatory discussions and evaluating strategic collaborations and partnership opportunities that could accelerate development and broaden global access." He noted that manufacturing scale-up planning is underway.

Paridiprubart is currently being evaluated in a separate U.S. government-funded study of ARDS patients. Enrollment is ongoing for up to approximately 200 randomized subjects for the Edesa cohort. The company's paridiprubart development program, including manufacturing scale-up, late-stage development and commercial readiness, also receives funding from the Government of Canada.

Edesa has been selected for an oral presentation at the American Thoracic Society (ATS) 2026 International Conference (May 15-20, 2026) and plans to present additional findings from its Phase 3 study at other upcoming medical and scientific conferences.

Detailed Results

Data were derived from the full study safety population of 278 patients; the previously reported 104-patient IMV ITT cohort represents a prespecified subset of this population. Patients in the full 278-patient safety population were randomly assigned (1:1) to SOC with paridiprubart (n=138), or SOC with placebo (n=140). Baseline characteristics and SOC were balanced between treatment groups.

The following tables summarize the key additional results:

Primary Endpoint: Mortality Rate at 28 Days

Multivariate Logistic Regression Derived Risk Differences, 95%CI

Population	Paridiprubart	Placebo	P-Value
All (n=278)	0.24 (0.21, 0.27)	0.33 (0.29, 0.37)	<0.001
IMV ITT (n=104)	0.39 (0.35, 0.44)	0.52 (0.47, 0.58)	<0.001

Adjusted model derived adjusted mortality estimates: variables included age, baseline WHO Covid-19 Severity Scale (WCSS), baseline antiviral use, baseline corticosteroid use, baseline immunomodulator use, concomitant antiviral use, concomitant corticosteroid use, concomitant immunomodulator use. All (safety population) n=278; Intent to treat (ITT) IMV population n=104

Secondary Endpoint: Achievement of ≥2-Point Improvement in WCSS at 28 Days

Multivariate Logistic Regression Derived Risk Differences, 95%CI

Population	Paridiprubart	Placebo	P-Value
All (n=278)	0.52 (0.48, 0.56)	0.45 (0.41-0.48)	<0.01
IMV ITT (n=104)	0.38 (0.31, 0.45)	0.27 (0.21, 0.33)	<0.05

Adjusted risk estimate: variables included age, baseline WCSS, baseline antiviral use, baseline corticosteroid use, baseline immunomodulator use, concomitant antiviral use, concomitant corticosteroid use, concomitant immunomodulator use. Safety population n=278; ITT IMV population n=104

Exploratory Analysis: Mortality Rate at 28 Days

Multivariate Logistic Regression Derived Risk Differences, 95%CI

Population	Paridiprubart	Placebo	P-Value*
Non-IMV (n=174)	0.15 (0.12, 0.18)	0.23 (0.19, 0.26)	<0.05
Pneumonia (n=108)	0.35 (0.29, 0.41)	0.49 (0.43, 0.55)	<0.05
Acute Kidney Injury (n=48)	0.35 (0.25, 0.44)	0.53 (0.44, 0.62)	<0.05
Sepsis (n=41)	0.40 (0.37, 0.43)	0.63 (0.59, 0.66)	<0.05

*Nominal p-value, not adjusted for multiplicity

Methodology and Background

Consistent with the original analysis, all prespecified efficacy evaluations were conducted under the same statistical analysis plan (SAP) using an identical multivariate logistic regression model and the same covariates. The SAP defined a hierarchical testing structure for adjusted 28‑day mortality for the full 278‑patient population as well as the 104‑patient IMV ITT population. Both analyses were prespecified and locked prior to unblinding. Exploratory analyses were subsequently conducted for the 174 non‑IMV randomized subjects, using the same model and covariates. Additional exploratory analyses were conducted for subjects with acute kidney injury, sepsis or pneumonia, using the same model but with subgroup‑appropriate covariates to account for clinical differences.

The study was managed and analyses were conducted by JSS Medical Research, an international contract research organization.

About Paridiprubart

Paridiprubart represents a new class of host directed therapeutics (HDTs) that are designed to modulate the body's own immune response when confronted with known or unknown public health threats such as novel infectious diseases as well as chemical, biological, radiological, and nuclear incidents. Importantly, HDTs are agnostic to the causal agent and can be stockpiled preemptively to respond to public health emergencies and biodefense. Mechanistically, paridiprubart inhibits toll-like receptor 4 (TLR4), a key immune signaling protein that has been shown to be activated by viruses, bacteria, injury/trauma and in the pathogenesis of chronic autoimmune diseases.

About ARDS

Acute Respiratory Distress Syndrome involves an exaggerated immune response leading to inflammation and injury to the lungs that prevents the lungs from oxygenating blood and ultimately deprives the body of oxygen. For moderate to severe cases, there are currently few recommended treatments other than supplemental oxygen and mechanical ventilation, and mortality rates are high. In addition to virus-induced pneumonia, ARDS can be caused by smoke/chemical inhalation, sepsis, chest injury, and other causes. ARDS accounts for 10% of intensive care unit admissions, representing more than 3 million patients globally each year.

About Edesa Biotech

Edesa Biotech, Inc. (NASDAQ:EDSA) is a clinical-stage biopharmaceutical company developing innovative ways to treat inflammatory and immune-related diseases. Its clinical pipeline is focused on two therapeutic areas: Medical Dermatology and Respiratory. In Medical Dermatology, Edesa is developing EB06, an anti-CXCL10 monoclonal antibody candidate, as a therapy for vitiligo, a common autoimmune disorder that causes skin to lose its color in patches. Its medical dermatology assets also include EB01 (1.0% daniluromer cream), a Phase 3-ready asset developed for use as a potential therapy for moderate-to-severe chronic Allergic Contact Dermatitis (ACD), a common occupational skin condition. The company's most advanced Respiratory drug candidate is EB05 (paridiprubart), which is being evaluated in a U.S. government-funded platform study as a treatment for Acute Respiratory Distress Syndrome, a life-threatening form of respiratory failure. The EB05 program has been the recipient of two funding awards from the Government of Canada to support the further development of this asset. Edesa is also pursuing additional uses for paridiprubart. Sign up for news alerts. Connect with us on X and LinkedIn.

Edesa Forward-Looking Statements

This press release may contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements may be identified by the use of words such as "anticipate," "believe," "plan," "estimate," "expect," "intend," "may," "will," "would," "could," "should," "might," "potential," or "continue" and variations or similar expressions, including statements related to: the company's belief that its existing resources are sufficient to achieve its near-term clinical milestones; the company's belief that results announced today align with the central role of TLR4 in hyperinflammatory ARDS and demonstrate consistent benefit across high mortality etiologies; the company's belief that the consistency of mortality reduction across 278 randomized patients, including those with ARDS complicated by acute kidney injury, sepsis and pneumonia, underscores the versatility and transformative potential of paridiprubart to address multiple critical unmet medical needs; the company's plans to advance regulatory discussions and evaluate strategic collaborations and partnership opportunities that could accelerate development and broaden global access; the company's planning for manufacturing scale up; the company's expectation that the U.S. government funded study will randomize up to 200 subjects in the paridiprubart cohort; the company's expectation that the Canadian government will continue to support development; the company's plans to present more detailed findings at upcoming medical and scientific conferences; and the company's timing and plans regarding its clinical studies in general. Readers should not unduly rely on these forward-looking statements, which are not a guarantee of future performance. There can be no assurance that forward-looking statements will prove to be accurate, as all such forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause actual results or future events to differ materially from the forward-looking statements. Such risks include: the ability of Edesa to obtain regulatory approval for or successfully commercialize any of its product candidates, the risk that access to sufficient capital to fund Edesa's operations may not be available or may be available on terms that are not commercially favorable to Edesa, the risk that Edesa's product candidates may not be effective against the diseases tested in its clinical trials, the risk that Edesa fails to comply with the terms of license agreements with third parties and as a result loses the right to use key intellectual property in its business, Edesa's ability to protect its intellectual property, the timing and success of submission, acceptance and approval of regulatory filings, and the impacts of public health crises. Many of these factors that will determine actual results are beyond the company's ability to control or predict. For a discussion of further risks and uncertainties related to Edesa's business, please refer to Edesa's public company reports filed with the U.S. Securities and Exchange Commission and the British Columbia Securities Commission. All forward-looking statements are made as of the date hereof and are subject to change. Except as required by law, Edesa assumes no obligation to update such statements.

Contact:

Gary Koppenjan

Edesa Biotech, Inc.

investors@edesabiotech.com

Edesa Biotech Reports Additional Positive Results from Phase 3 Paridiprubart Study