Antiviral effect of Bromelain combined with acetylcysteine against SARS-CoV-2 Omicron variant
Erik Vinicius De Sousa Reis, Linziane Lopes Ferreira, Felipe Alves Clarindo, Geovane Marques-Ferreira, Leonardo Camilo De Oliveira, Thaís De Fátima Silva Moraes, Luciana Debortoli De Carvalho, Flávio Guimarães Da Fonseca, Adriano De Paula Sabino, Mathew Suji Eapen, Mauro Martins Teixeira, Sarah J Valle, David L Morris, Jordana Grazziela Alves Coelho-Dos-Reis
Scientific Reports, doi:10.1038/s41598-025-92242-y
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 antiinflammatory 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.
Author contributions Designing research study: DLM, SJV, JGCdR. Conducting experiments, acquiring data: EVSR, LLF, FAC, GMF, LCO, TFSM. Analyzing data: EVSR, LDC, TFSM, JGCdR. Advisory Committee: FGF, APS, MSE, MMT. Provided reagents and funding: FGF, APS, MMT, SJV, DLM, JGCdR. Supervised research project and acquired funding: SJV, DLM, JGCdR. Writing the manuscript: EVSR, MMT, LLF, TFSM, SJV, MSE, DLM, TFSM, JGCdR. All authors reviewed and approved the final version.
Declarations
Competing interests The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. DLM, SJV and MSE are employed by MucPharm. All the remaining authors declare no conflict of interest.
Ethics approval and consent to participate Research was approved by Institutional Research Board Committee. This research had approval from the Brazilian Institutional Ethics Committee (Approval number: 45919121.6.0000.5526). There was written consent from the next of kin on behalf of the patients for participation in the research. This study followed the principles of the Helsinki Declaration and resolution #466/2012 of the Brazilian Ministry of Health for research involving human subjects.
Consent for publication Informed consent was obtained by next of kin of all participants enrolled in the study.
Additional information
Supplementary Information The online version contains supplementary..
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