Pamela Cruz. Peninsula 360 Press [P360P]
After several tests in experimental laboratories in France and the U.S., it was shown that plitidepsin, an antiviral drug produced by the Spanish company PharmaMar, could reduce SARS-CoV-2 viral loads by up to 99 percent.
According to a publication presented Monday in the journal Science, in vitro and in vivo experiments that have already been conducted in animals with this drug, used as an antitumor, have shown promising antiviral efficacy and toxicity profile.
Thus, the authors of the study have concluded that plitidepsin is "by far" the most potent compound discovered so far against SARS-CoV-2, so they have proposed that the drug should be tested in expanded clinical trials for the treatment of COVID-19.
Similarly, they have determined that "the antiviral activity of plitidepsin against SARS-CoV-2 occurs through the inhibition of a known target -the eEF1A-" and have ensured that the drug has demonstrated, in vitro, a strong antiviral potency compared to others against the virus, and also with limited toxicity.
The assay, conducted in two different types of animals, demonstrated a reduction in viral replication, with a 99 percent decrease in viral loads in the lung of plitidepsin-treated specimens.
And while toxicity is a concern with any antiviral targeting a human cell protein, the safety profile of plitidepsin is well established in humans, the paper notes.
The researchers also noted that the well-tolerated doses of this drug used in the COVID-19 clinical trial are even lower than those used in these experiments.
In this sense, the publication concludes that plitidepsin acts by blocking the aforementioned protein -a eEF1A-, which is present in human cells, and which is used by SARS-CoV-2 as a vehicle to reproduce and infect other cells.
"We believe that our data and the initial positive results from the PharmaMar clinical trial suggest that plitidepsin should be strongly considered for expanded clinical trials for the treatment of COVID-19," the researchers said.
In the same note, the Spanish company stressed that the group of researchers who reached these conclusions, was the first to draw a comprehensive map of the genome of COVID-19 and to discover that the virus interacts with 332 proteins in human cells.
The Spanish biopharmaceutical company PharmaMar is currently in negotiations with various regulatory bodies to commence Phase III trials of the drug.
