SoftOx Solutions AS: POSITIVE TOPLINE SAFETY DATA FROM SIS-03 DOSE-ESCALATION PHASE

Dose escalation completed with no serious adverse events observed, supporting continued execution of the SIS-03 proof-of-concept/Phase 2a patient phase

Oslo/Copenhagen – SoftOx Solutions AS (“SoftOx”), a clinical-stage pharmaceutical company developing a novel anti-infective therapy for airway infections, today announces positive topline safety data from the dose-escalation phase of the SIS-03 Phase 2a clinical program.

Reference is made to the stock notice on June 8, 2026, where the Company announced that the dose-escalation phase of the SIS-03 clinical program had been completed, that the program would advance into the proof-of-concept (“PoC”) phase, and that the outcome of the safety review of the dose-escalation phase, conducted in healthy volunteers, would be communicated later this year. The safety topline review has now been completed, and no serious adverse events were observed, nor were any severe tolerability or safety issues recorded during the dose-escalation phase.

POSITIVE TOPLINE SAFETY REVIEW SUPPORTS CONTINUED SIS-03 EXECUTION SIS-03 is evaluating SoftOx Inhalation Solution (“SIS”) as an inhaled anti-infective therapy for chronic airway infections in patients with cystic fibrosis, and the positive outcome of the safety review supports the continued execution of the ongoing PoC/Phase 2a patient phase of SIS-03.

CONTINUED ADVANCEMENT OF THE PROOF-OF-CONCEPT PATIENT PHASE “We are very pleased with the topline safety outcome from the dose-escalation phase of SIS-03. Completing the dose-escalation phase with no serious adverse events observed and no severe tolerability issues recorded is an important step forward for our SIS-03 program. Tolerability is important not only for clinical development, but also for potential future use in real-world treatment settings, where patients need therapies that are both effective and manageable. Concluding this review on a positive note is therefore good news for SoftOx and for the continued development of SIS as a potential treatment option for patients with chronic airway infections,” stated Thomas Bjarnsholt, CEO of SoftOx.

No additional detailed safety, tolerability, efficacy, or microbiological data are disclosed in this announcement. The Company will provide further updates on the SIS-03 clinical program when relevant milestones are reached.

The SIS-03 clinical trial program is being conducted in collaboration with Rigshospitalet in Copenhagen, Denmark, and the ongoing PoC/Phase 2a patient phase is designed to assess clinical and microbiological signals relevant to establishing proof-of-concept for SIS, including data on bacterial load reduction in patients’ airways. This phase of the trial is expected to conclude in H1 2027.

SIS-03 remains separate from the Company’s other ongoing SIS-02 clinical program.

POTENTIAL COMMERCIAL RELEVANCE IN CHRONIC AIRWAY INFECTIONS Based on Company estimates, approximately 13,000 patients with cystic fibrosis across the US and EU4+UK receive chronic inhaled antibiotic therapy, representing a market of more than USD 600 million annually. SoftOx believes SIS’s mechanism may also be relevant to non-CF bronchiectasis, a significantly larger indication affecting approximately 445,000 patients, with a potential market opportunity exceeding USD 5 billion.

About SIS: SoftOx Solutions AS is developing SIS, a novel inhaled anti-infective therapy for respiratory infections in the airways and lungs. SIS targets biofilm-associated infections through a patented, non-antibiotic mechanism designed to reduce the risk of resistance development. Delivered by nebulizer, SIS is being developed to address bacterial, viral, and fungal pathogens through local delivery directly at the site of infection, without systemic exposure to the remainder of the human body. Its broad pathogen relevance positions SIS as a distinct therapeutic in respiratory infections.

About SoftOx Solutions AS: SoftOx Solutions AS (ticker: SOFTX) is a clinical-stage pharmaceutical company developing SIS (SoftOx Inhalation Solution), a novel inhaled anti-infective therapy for the treatment of respiratory infections in the airways and lungs. The Company is also exploring the potential dual-use relevance of SIS within civilian health security and biological preparedness. SoftOx is listed on Euronext Growth Oslo.

For more information, please contact: Ulrik Spork, Chairman of the Board, SoftOx Solutions AS, +45 31 38 83 87 Thomas Bjarnsholt, CEO, SoftOx Solutions AS, +45 20 65 98 88 Mail: ir@soft-ox.com

This information is subject to the disclosure requirements pursuant to section 5-12 of the Norwegian Securities Trading Act.