A sprayable Acid-Oxidizing solution containing hypochlorous acid (AOS2020) efficiently and safely inactivates SARS-Cov-2: a new potential solution for upper respiratory tract hygiene

Eur Arch Otorhinolaryngol. 2021 Aug;278(8):3099-3103. doi: 10.1007/s00405-021-06644-5. Epub 2021 Feb 11.


Introduction: To eliminate the COVID-19 pandemic, the transmission of the virus SARS-CoV-2 among the population needs to be blocked and/or at least reduced. Upper respiratory tract viral loads are highest in the early stages of the disease, and high loads are associated with higher mortality rates. This study aims to evaluate the virucidal efficacy of AOS2020, a novel sprayable Acid-Oxidizing solution containing pure and stable hypochlorous acid (HClO), on human coronavirus SARS-Cov-2 in vitro, and the tolerability profile on nasal and oral mucosa suggesting to be a potential solution for upper respiratory hygiene.

Method: Virucidal assays and intranasal and oral irritation tests were undertaken in accordance with relevant national and international guidance and methods.

Results: In pre-clinical tests, the AOS2020, showed > 99.8% virucidal efficacy in < 1 min against SARS-Cov-2. The safety profile testing on both the nasal and oral mucosa indicates that AOS2020 is non-irritant.

Conclusion: These initial results indicate that this product has the potential treatment to reduce viral load in the upper respiratory tract.

Keywords: Acid-Oxidizing solution (AOS2020); Hypochlorous acid (HClO); SARS-CoV-2; Upper respiratory tract; Viral load.

MeSH terms

  • COVID-19*
  • Humans
  • Hygiene
  • Hypochlorous Acid / pharmacology
  • Nose
  • Oxidation-Reduction
  • Pandemics
  • SARS-CoV-2*


  • Hypochlorous Acid