Antiviral effect of Bromelain combined with acetylcysteine against SARS-CoV-2 Omicron variant.

The recent pandemic represented one of the biggest challenges of modern civilization. SARS-CoV-2 remains an imminent public health threat and currently, there is no effective and greatly affordable treatment for severe COVID-19. Although standard management with dexamethasone, and physical management including physiotherapy, prone positioning and mechanical ventilation are used, severe disease patients may still succumb to infection. In this regard, BromAc(®) is a combination therapy of a refined protein derived from Bromelain and acetylcysteine, that shows significant mucolytic and anti-inflammatory properties. In the present study, we performed in vitro, and ex vivo analyses to assess the effect of BromAc(®) in inhibiting Omicron variant of SARS-CoV-2 at different levels. Here, we provide evidence of the in vitro virucidal activity of BromAc(®) in Vero-ACE2/TMPRSS2 cell line infected with the Omicron variant. BromAc(®) can also abrogate SARS-CoV-2 RNA genomic copies in tracheal aspirate (TA) samples from critically ill COVID-19 patients after long term exposure. These results were confirmed by lower spike expression observed in EpCAM(+)PanCK(neg) epithelial cells from tracheal aspirate samples after BromAc(®) treatment. Furthermore, atomized BromAc(®) promoted cleavage of the S1 Spike subunit in TA samples, demonstrating the mechanism of the antiviral activity displayed by BromAc(®) in human samples. These results bring novel evidence of antiviral activity in cell lines in vitro as well as in tracheal aspirate samples from critically ill COVID-19 patients, which support its potential use as an adjunct to COVID-19 management in future waves of Omicron subvariants.