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bioRxiv · 10.1101/2020.12.02.408575

In Vitro Analysis of the Anti-viral Potential of nasal spray constituents against SARS-CoV-2

Cannon, M. L.·Westover, J. B.·Bleher, R.·Sanchez-Gonzalez, M. A.·Ferrer, G.
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Abstract

Viral pandemics have taken a significant toll on humanity and the world now is contending with the SARS-CoV-2 epidemic. Readily available economical preventive measures should be immediately explored. Xylitol has been reported to reduce the severity of viral infections as well as the severity of pneumonia, and increase the survivability of animal subjects. Since pneumonia and acute respiratory distress syndrome are potentially fatal complications of COVID-19, the present study tested the in vitro effectiveness of xylitol against SARS-CoV-2. Virus titers and LRV of SARS-CoV-2, were incubated with a single concentration of nasal spray. Toxicity was observed in the top dilution (1/10). Virus was seen below that dilution so it did not affect calculations of virus titer or LRV. After a 25-minute contact time, the nasal spray (11% Pure Xylitol, 0.85%NaCL (Saline), and 0.20% grapefruit seed extract) reduced virus from 4.2 to 1.7 log10 CCID50 per 0.1 mL, a statistically significant reduction (P<0.001) of 2.5 log10 CCID50. STEM Images obtained at the BIoCryo Laboratory revealed virus contained on the cell wall but none intra-cellular, possibly due to D-xylose (xylitol) production of glycoaminoglycans decoy targets. Xylitol and grapefruit seed extract are not exotic nor expensive rare high technology answers to viral epidemics. The potential in saving lives and the economies of the world by using X-GSE combination therapy should inspire large clinical trials, especially in those nations whereas the healthcare system would be dangerously compromised by the adoption of less effective and significantly more financially demanding therapies. Because there are no risk factors in using the X/GSE combination therapy, and the nasal spray is over the counter available without a prescription, and the spray allows for comfortable long term mask-wearing, adoption of this preventive anti-viral therapy should be encouraged.

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Cannon, M. L., Westover, J. B., Bleher, R., Sanchez-Gonzalez, M. A., Ferrer, G.. 2020-12-03. In Vitro Analysis of the Anti-viral Potential of nasal spray constituents against SARS-CoV-2. https://doi.org/10.1101/2020.12.02.408575

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