The virus that causes Covid-19 is developing resistance to two drugs used to treat patients with infections, scientists now say.
According to findings released this year, the medicines, one known as nirmatrelvir and the other remdesivir, have been found to be less effective as the virus that causes coronavirus is becoming resistant to both drugs.
The studies were published in the Jama Network Open and the Nature Communications Journals.
A higher possibility of finding viruses that cause Covid-19 was linked to patients who had taken the antiviral drugs as well as low sensitivity to the treatment doses (nirmatrelvir and remdesivir), as indicated in the two studies.
In the first study, 156 Covid-19 patients were treated with the antiviral drug and observed over a span of two years between 2021-2023.
The researchers from Brigham and Women’s Hospital, the University of Pittsburgh, the Harvard University and Stanford University, further divided the patients into two categories: those who did not take the drug and those who took it.
Immune system
A higher likelihood of having viruses with changes that are resistant to nirmatrelvir was found in patients who took the antiviral treatment.
Patients who took nirmatrelvir and those who had a compromised immune system had more pronounced effects.
“Subjects treated with nirmatrelvir were found to have higher resistance mutations, particularly those who had a suppressed immunity, compared to patients who were not treated,” the study read in part.
“All mutations, however, were present but they appeared briefly, at very low frequencies, and they were less likely to contribute to virologic rebound.”
In the second study, 15 Covid patients were given the remdesivir drug before a team of researchers from the National Institutes of Health and the Cornell University examined their outcomes.
When the researchers arranged its DNA pattern, the Covid-19 virus infecting the patients was found to have developed a lower sensitivity level to both nirmatrelvir and remdesivir drugs.
The mutated viruses were also found to have the ability to infect others who were nearby.
