Light instead of antibiotics: Ondine’s Phase 3 trial is weeks away from results that could reshape surgical infection prevention

A five-minute pre-surgical procedure using light is about to face its biggest test — and the clinical trial metrics, according to the company, are unusually clean.

The global burden of antimicrobial resistance is well documented. According to a 2022 analysis published in The Lancet, bacterial antimicrobial resistance was associated with approximately 4.95 million deaths in 2019 alone, with drug-resistant infections directly causing an estimated 1.27 million of those deaths. Surgical site infections (SSIs) represent a significant portion of this burden: according to the US Centers for Disease Control and Prevention (CDC), they account for approximately 20% of all hospital-acquired infections.

The current standard of care for preventing SSIs caused by nasal carriage of bacteria is mupirocin, a topical antibiotic applied twice daily for five days before surgery. According to a 2019 study in Infection Control & Hospital Epidemiology, compliance with this regimen can fall as low as 39%. Mupirocin resistance is also a growing concern, with resistance rates exceeding 50% in some clinical settings, according to a 2021 review in Clinical Microbiology Reviews.

Ondine Biomedical (AIM: OBI) is developing a non-antibiotic alternative that bypasses both problems. This spring, the company expects to learn whether its approach works in the largest trial ever conducted for this indication.

What photodisinfection is — and why it matters

Ondine’s nasal photodisinfection, marketed as Steriwave® in Canada and the UK, is a procedure that uses a light-activated photosensitizing agent applied to the nasal passages. When exposed to specific red light wavelengths, the agent produces a burst of reactive oxygen that destroys bacteria, viruses, and fungi — including antibiotic-resistant strains like MRSA — by disrupting their cell membranes. The procedure takes approximately five minutes.

According to Ondine’s own materials, the mechanism of action is physical rather than chemical, meaning it does not create the selective pressure that drives antimicrobial resistance. As the company has stated in investor presentations, this distinguishes it from antibiotics and explains its effectiveness against drug-resistant organisms.

According to the company, Steriwave has been in clinical use in Canadian hospitals for over a decade and has been adopted by several NHS trusts in the United Kingdom.

The Phase 2 evidence base

The clinical rationale for the Phase 3 trial rests on earlier data. According to Ondine’s presentations at the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) in 2023, a Phase 2 study showed that patients who underwent nasal photodisinfection prior to surgery experienced fewer surgical site infections than published historical benchmarks. The same data showed that the treatment reduced or eliminated nasal carriage of Staphylococcus aureus, including MRSA, in the majority of treated patients immediately after the procedure.

These findings, while not from a randomized controlled trial large enough for registration, supported the design of the pivotal study now nearing completion.

The LANTERN Phase 3 trial: what the company has disclosed

According to a company regulatory news announcement on March 10, 2026, the LANTERN trial has enrolled more than 5,000 surgical patients across 14 HCA Healthcare hospitals in the United States and four major Canadian medical centres. The study is designed to compare standard infection prevention practices with and without Ondine’s nasal photodisinfection.

According to the same announcement, as of early March 2026:

• Over 92% of clinical report forms are complete

• Approximately 80% of monitoring visits have been finalized

• Nearly 80% of primary endpoint adjudications are complete

• Participant retention exceeds 98%

The 98% retention rate, if confirmed in the final dataset, is exceptionally high for a trial of this size and duration. It suggests that the data set entering the final analysis will have minimal missing information — a factor that reduces statistical uncertainty and strengthens the reliability of the readout.

According to the announcement, top-line results are expected in spring 2026. The analysis will include the estimated treatment effect on surgical site infection rates comparing treatment to control groups, along with primary safety data.

The HCA partnership and its significance

The trial is being conducted in collaboration with HCA Healthcare, the largest for-profit hospital operator in the United States. HCA’s willingness to run this trial across 14 of its facilities — at its own clinical sites, with its own patients and surgeons — reflects institutional interest in a potential solution to a costly and dangerous problem.

Surgical site infections are associated with substantial costs. According to a 2020 analysis by the Agency for Healthcare Research and Quality (AHRQ), they extend hospital stays by an average of 9 to 11 days and increase hospitalization costs by $20,000 to $30,000 per admission. For a hospital system the size of HCA, a clinically validated intervention that reduces SSI rates would have both patient care and financial implications.

If the LANTERN data are positive, HCA is positioned to be an early adopter. The company has not announced any commercial agreement with Ondine beyond the trial collaboration.

The regulatory opportunity

According to the US Food and Drug Administration (FDA) database, there is currently no FDA-approved product indicated specifically for nasal decolonization to prevent surgical site infections. Mupirocin is used for this purpose, but it is not approved for that indication and is applied off-label.

Ondine has stated in previous disclosures that a positive LANTERN readout would form the basis of a submission to the FDA. If approved, the technology would be the first product in this category to receive FDA clearance — a potential first-mover advantage in a market of significant size.

According to the CDC, approximately 50 million inpatient and outpatient surgical procedures are performed annually in the United States. Even adoption concentrated in high-risk procedures such as cardiac, orthopaedic, and neurosurgeries would represent a substantial commercial opportunity.

The risks that remain

Ondine is a small, clinical-stage company listed on AIM. It faces the usual risks of any development-stage biotech: the Phase 3 results may not meet their endpoints; regulatory timelines may extend; and commercial adoption, even with positive data, is not guaranteed. The company’s financial position and cash runway should be evaluated by investors alongside the clinical data.

What happens next

The LANTERN trial is not the first study of nasal photodisinfection, but it seems to be the largest and the most rigorously designed. With more than 5,000 patients enrolled, completion metrics that suggest a clean dataset, and results expected within weeks, the trial represents a binary event for Ondine and a potential inflection point for the field of surgical infection prevention.

The question the data will answer is straightforward: does a five-minute, light-based procedure applied before surgery meaningfully reduce the incidence of infections that kill patients, extend hospital stays, and cost the healthcare system billions — without contributing to the very resistance crisis that makes those infections harder to treat?

The answer is expected this spring.