Nasal Photodisinfection COVID-19 Proof of Concept Study

The study proposes to test photodisinfection (PDF) on SARS-CoV-2 in the nose. The study will use Health Canada approved Steriwave™ Nasal Decolonization (ND) in he nostril of patients infected with SARS-CoV-2. Participants are swabbed for SARS-CoV-2 before and after the PDF treatment. For the study, a small group of healthcare workers who have tested positive for SARS-CoV-2 will be included. They will not undergo the treatment but will need to swab their noses multiple times over the next 5 days. This nil group will provide the effect (if any) of swabbing SARS-CoV-2 levels in the nose.

The study proposes to test photodisinfetion (PDF) on levels of SARS-CoV-2 in the nose. The study will use Health Canada approved Steriwave™ Nasal Decolonization (ND) in patients infected with SARS-CoV-2 . Currrently, PDF is being used at some institutions before surgery to lower the risk of postoperative infection. PDF uses a Methylene Blue (MB) nasal spray, followed by 5 minutes of red-light exposure through a small light-diffusing applicator. This will need to be placed into each nostril. Participants are swabbed for SARS-CoV-2 before and after treatment. In addition to the patients testing positive for SARS-CoV-2, there will also be a small group of healthcare workers who have tested positive that will be included. Though they are not undergoing treatment, they will swab their own noses multiple times over a period of 5 days. This will allow us to evaluate the effect (if any) of swabbing on SARS-CoV-2 levels in the nose. The study hypothesis is that MB-mediated PDF will show the ability to kill SARS-CoV-2 which will consequently confirm its efficacy as a first line defense against the virus.

There is only a single group of patients in the study who will undergo treatment. There is a small sub group/'nil' group of 3 healthcare workers that will not be undergoing the treatment but will instead be doing multiple nasal swabbing in the course of 5 days.

The Health-Canada approved Steriwave system (Ondine Biomedical, BC) will be used to deliver the Methylene Blue-Photodisinfection (MB-PDF) to the anterior nares.

Participants will receive a pre-treatment nasal swab followed MB-PDF, this involves an MB nasal spray, followed by five minutes of red-light exposure into each nostril. Ten minutes after the treatment, a post treatment nasal swab will be performed.

The main endpoint is microbiological; RT-qPCR will be conducted on the pre and post treatment swabs and the change in cycle threshold value will be measured

Inclusion Criteria (patient population): Recent SARS-CoV-2+ diagnosis Present in hospital Inclusion Criteria (healthcare workers): Recent SARS-CoV-2+ diagnosis Ability to self-administer nasal swabs Exclusion Criteria (patient population): Immediate requirement for intubation (i.e. emergency airway) or inability to maintain independent oral airway Exclusion Criteria (healthcare workers): None

Lobo CS, Rodrigues-Santos P, Pereira D, Nunez J, Trepa JCD, Sousa DL, Lourenco JV, Coelho MF, de Almeida LP, da Cunha JS, Arnaut LG. Photodynamic disinfection of SARS-CoV-2 clinical samples using a methylene blue formulation. Photochem Photobiol Sci. 2022 Jun;21(6):1101-1109. doi: 10.1007/s43630-022-00202-6. Epub 2022 Mar 19.